* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (22 commits)
ioat: fix self test for multi-channel case
dmaengine: bump initcall level to arch_initcall
dmaengine: advertise all channels on a device to dma_filter_fn
dmaengine: use idr for registering dma device numbers
dmaengine: add a release for dma class devices and dependent infrastructure
ioat: do not perform removal actions at shutdown
iop-adma: enable module removal
iop-adma: kill debug BUG_ON
iop-adma: let devm do its job, don't duplicate free
dmaengine: kill enum dma_state_client
dmaengine: remove 'bigref' infrastructure
dmaengine: kill struct dma_client and supporting infrastructure
dmaengine: replace dma_async_client_register with dmaengine_get
atmel-mci: convert to dma_request_channel and down-level dma_slave
dmatest: convert to dma_request_channel
dmaengine: introduce dma_request_channel and private channels
net_dma: convert to dma_find_channel
dmaengine: provide a common 'issue_pending_all' implementation
dmaengine: centralize channel allocation, introduce dma_find_channel
dmaengine: up-level reference counting to the module level
...
3.6 Constraints
3.7 Example
-4 DRIVER DEVELOPER NOTES
+4 DMAENGINE DRIVER DEVELOPER NOTES
4.1 Conformance points
-4.2 "My application needs finer control of hardware channels"
+4.2 "My application needs exclusive control of hardware channels"
5 SOURCE
implementation examples.
4 DRIVER DEVELOPMENT NOTES
+
4.1 Conformance points:
There are a few conformance points required in dmaengine drivers to
accommodate assumptions made by applications using the async_tx API:
3/ Use async_tx_run_dependencies() in the descriptor clean up path to
handle submission of dependent operations
-4.2 "My application needs finer control of hardware channels"
-This requirement seems to arise from cases where a DMA engine driver is
-trying to support device-to-memory DMA. The dmaengine and async_tx
-implementations were designed for offloading memory-to-memory
-operations; however, there are some capabilities of the dmaengine layer
-that can be used for platform-specific channel management.
-Platform-specific constraints can be handled by registering the
-application as a 'dma_client' and implementing a 'dma_event_callback' to
-apply a filter to the available channels in the system. Before showing
-how to implement a custom dma_event callback some background of
-dmaengine's client support is required.
-
-The following routines in dmaengine support multiple clients requesting
-use of a channel:
-- dma_async_client_register(struct dma_client *client)
-- dma_async_client_chan_request(struct dma_client *client)
-
-dma_async_client_register takes a pointer to an initialized dma_client
-structure. It expects that the 'event_callback' and 'cap_mask' fields
-are already initialized.
-
-dma_async_client_chan_request triggers dmaengine to notify the client of
-all channels that satisfy the capability mask. It is up to the client's
-event_callback routine to track how many channels the client needs and
-how many it is currently using. The dma_event_callback routine returns a
-dma_state_client code to let dmaengine know the status of the
-allocation.
-
-Below is the example of how to extend this functionality for
-platform-specific filtering of the available channels beyond the
-standard capability mask:
-
-static enum dma_state_client
-my_dma_client_callback(struct dma_client *client,
- struct dma_chan *chan, enum dma_state state)
-{
- struct dma_device *dma_dev;
- struct my_platform_specific_dma *plat_dma_dev;
-
- dma_dev = chan->device;
- plat_dma_dev = container_of(dma_dev,
- struct my_platform_specific_dma,
- dma_dev);
-
- if (!plat_dma_dev->platform_specific_capability)
- return DMA_DUP;
-
- . . .
-}
+4.2 "My application needs exclusive control of hardware channels"
+Primarily this requirement arises from cases where a DMA engine driver
+is being used to support device-to-memory operations. A channel that is
+performing these operations cannot, for many platform specific reasons,
+be shared. For these cases the dma_request_channel() interface is
+provided.
+
+The interface is:
+struct dma_chan *dma_request_channel(dma_cap_mask_t mask,
+ dma_filter_fn filter_fn,
+ void *filter_param);
+
+Where dma_filter_fn is defined as:
+typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
+
+When the optional 'filter_fn' parameter is set to NULL
+dma_request_channel simply returns the first channel that satisfies the
+capability mask. Otherwise, when the mask parameter is insufficient for
+specifying the necessary channel, the filter_fn routine can be used to
+disposition the available channels in the system. The filter_fn routine
+is called once for each free channel in the system. Upon seeing a
+suitable channel filter_fn returns DMA_ACK which flags that channel to
+be the return value from dma_request_channel. A channel allocated via
+this interface is exclusive to the caller, until dma_release_channel()
+is called.
+
+The DMA_PRIVATE capability flag is used to tag dma devices that should
+not be used by the general-purpose allocator. It can be set at
+initialization time if it is known that a channel will always be
+private. Alternatively, it is set when dma_request_channel() finds an
+unused "public" channel.
+
+A couple caveats to note when implementing a driver and consumer:
+1/ Once a channel has been privately allocated it will no longer be
+ considered by the general-purpose allocator even after a call to
+ dma_release_channel().
+2/ Since capabilities are specified at the device level a dma_device
+ with multiple channels will either have all channels public, or all
+ channels private.
5 SOURCE
-include/linux/dmaengine.h: core header file for DMA drivers and clients
+
+include/linux/dmaengine.h: core header file for DMA drivers and api users
drivers/dma/dmaengine.c: offload engine channel management routines
drivers/dma/: location for offload engine drivers
include/linux/async_tx.h: core header file for the async_tx api
--- /dev/null
+See Documentation/crypto/async-tx-api.txt
at32_add_device_mci(unsigned int id, struct mci_platform_data *data)
{
struct platform_device *pdev;
- struct dw_dma_slave *dws;
+ struct dw_dma_slave *dws = &data->dma_slave;
u32 pioa_mask;
u32 piob_mask;
ARRAY_SIZE(atmel_mci0_resource)))
goto fail;
- if (data->dma_slave)
- dws = kmemdup(to_dw_dma_slave(data->dma_slave),
- sizeof(struct dw_dma_slave), GFP_KERNEL);
- else
- dws = kzalloc(sizeof(struct dw_dma_slave), GFP_KERNEL);
-
- dws->slave.dev = &pdev->dev;
- dws->slave.dma_dev = &dw_dmac0_device.dev;
- dws->slave.reg_width = DMA_SLAVE_WIDTH_32BIT;
+ dws->dma_dev = &dw_dmac0_device.dev;
+ dws->reg_width = DW_DMA_SLAVE_WIDTH_32BIT;
dws->cfg_hi = (DWC_CFGH_SRC_PER(0)
| DWC_CFGH_DST_PER(1));
dws->cfg_lo &= ~(DWC_CFGL_HS_DST_POL
| DWC_CFGL_HS_SRC_POL);
- data->dma_slave = &dws->slave;
-
if (platform_device_add_data(pdev, data,
sizeof(struct mci_platform_data)))
goto fail;
#include <linux/async_tx.h>
#ifdef CONFIG_DMA_ENGINE
-static enum dma_state_client
-dma_channel_add_remove(struct dma_client *client,
- struct dma_chan *chan, enum dma_state state);
-
-static struct dma_client async_tx_dma = {
- .event_callback = dma_channel_add_remove,
- /* .cap_mask == 0 defaults to all channels */
-};
-
-/**
- * dma_cap_mask_all - enable iteration over all operation types
- */
-static dma_cap_mask_t dma_cap_mask_all;
-
-/**
- * chan_ref_percpu - tracks channel allocations per core/opertion
- */
-struct chan_ref_percpu {
- struct dma_chan_ref *ref;
-};
-
-static int channel_table_initialized;
-static struct chan_ref_percpu *channel_table[DMA_TX_TYPE_END];
-
-/**
- * async_tx_lock - protect modification of async_tx_master_list and serialize
- * rebalance operations
- */
-static spinlock_t async_tx_lock;
-
-static LIST_HEAD(async_tx_master_list);
-
-/* async_tx_issue_pending_all - start all transactions on all channels */
-void async_tx_issue_pending_all(void)
-{
- struct dma_chan_ref *ref;
-
- rcu_read_lock();
- list_for_each_entry_rcu(ref, &async_tx_master_list, node)
- ref->chan->device->device_issue_pending(ref->chan);
- rcu_read_unlock();
-}
-EXPORT_SYMBOL_GPL(async_tx_issue_pending_all);
-
-/* dma_wait_for_async_tx - spin wait for a transcation to complete
- * @tx: transaction to wait on
- */
-enum dma_status
-dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
-{
- enum dma_status status;
- struct dma_async_tx_descriptor *iter;
- struct dma_async_tx_descriptor *parent;
-
- if (!tx)
- return DMA_SUCCESS;
-
- /* poll through the dependency chain, return when tx is complete */
- do {
- iter = tx;
-
- /* find the root of the unsubmitted dependency chain */
- do {
- parent = iter->parent;
- if (!parent)
- break;
- else
- iter = parent;
- } while (parent);
-
- /* there is a small window for ->parent == NULL and
- * ->cookie == -EBUSY
- */
- while (iter->cookie == -EBUSY)
- cpu_relax();
-
- status = dma_sync_wait(iter->chan, iter->cookie);
- } while (status == DMA_IN_PROGRESS || (iter != tx));
-
- return status;
-}
-EXPORT_SYMBOL_GPL(dma_wait_for_async_tx);
-
-/* async_tx_run_dependencies - helper routine for dma drivers to process
- * (start) dependent operations on their target channel
- * @tx: transaction with dependencies
- */
-void async_tx_run_dependencies(struct dma_async_tx_descriptor *tx)
-{
- struct dma_async_tx_descriptor *dep = tx->next;
- struct dma_async_tx_descriptor *dep_next;
- struct dma_chan *chan;
-
- if (!dep)
- return;
-
- chan = dep->chan;
-
- /* keep submitting up until a channel switch is detected
- * in that case we will be called again as a result of
- * processing the interrupt from async_tx_channel_switch
- */
- for (; dep; dep = dep_next) {
- spin_lock_bh(&dep->lock);
- dep->parent = NULL;
- dep_next = dep->next;
- if (dep_next && dep_next->chan == chan)
- dep->next = NULL; /* ->next will be submitted */
- else
- dep_next = NULL; /* submit current dep and terminate */
- spin_unlock_bh(&dep->lock);
-
- dep->tx_submit(dep);
- }
-
- chan->device->device_issue_pending(chan);
-}
-EXPORT_SYMBOL_GPL(async_tx_run_dependencies);
-
-static void
-free_dma_chan_ref(struct rcu_head *rcu)
-{
- struct dma_chan_ref *ref;
- ref = container_of(rcu, struct dma_chan_ref, rcu);
- kfree(ref);
-}
-
-static void
-init_dma_chan_ref(struct dma_chan_ref *ref, struct dma_chan *chan)
-{
- INIT_LIST_HEAD(&ref->node);
- INIT_RCU_HEAD(&ref->rcu);
- ref->chan = chan;
- atomic_set(&ref->count, 0);
-}
-
-/**
- * get_chan_ref_by_cap - returns the nth channel of the given capability
- * defaults to returning the channel with the desired capability and the
- * lowest reference count if the index can not be satisfied
- * @cap: capability to match
- * @index: nth channel desired, passing -1 has the effect of forcing the
- * default return value
- */
-static struct dma_chan_ref *
-get_chan_ref_by_cap(enum dma_transaction_type cap, int index)
-{
- struct dma_chan_ref *ret_ref = NULL, *min_ref = NULL, *ref;
-
- rcu_read_lock();
- list_for_each_entry_rcu(ref, &async_tx_master_list, node)
- if (dma_has_cap(cap, ref->chan->device->cap_mask)) {
- if (!min_ref)
- min_ref = ref;
- else if (atomic_read(&ref->count) <
- atomic_read(&min_ref->count))
- min_ref = ref;
-
- if (index-- == 0) {
- ret_ref = ref;
- break;
- }
- }
- rcu_read_unlock();
-
- if (!ret_ref)
- ret_ref = min_ref;
-
- if (ret_ref)
- atomic_inc(&ret_ref->count);
-
- return ret_ref;
-}
-
-/**
- * async_tx_rebalance - redistribute the available channels, optimize
- * for cpu isolation in the SMP case, and opertaion isolation in the
- * uniprocessor case
- */
-static void async_tx_rebalance(void)
-{
- int cpu, cap, cpu_idx = 0;
- unsigned long flags;
-
- if (!channel_table_initialized)
- return;
-
- spin_lock_irqsave(&async_tx_lock, flags);
-
- /* undo the last distribution */
- for_each_dma_cap_mask(cap, dma_cap_mask_all)
- for_each_possible_cpu(cpu) {
- struct dma_chan_ref *ref =
- per_cpu_ptr(channel_table[cap], cpu)->ref;
- if (ref) {
- atomic_set(&ref->count, 0);
- per_cpu_ptr(channel_table[cap], cpu)->ref =
- NULL;
- }
- }
-
- for_each_dma_cap_mask(cap, dma_cap_mask_all)
- for_each_online_cpu(cpu) {
- struct dma_chan_ref *new;
- if (NR_CPUS > 1)
- new = get_chan_ref_by_cap(cap, cpu_idx++);
- else
- new = get_chan_ref_by_cap(cap, -1);
-
- per_cpu_ptr(channel_table[cap], cpu)->ref = new;
- }
-
- spin_unlock_irqrestore(&async_tx_lock, flags);
-}
-
-static enum dma_state_client
-dma_channel_add_remove(struct dma_client *client,
- struct dma_chan *chan, enum dma_state state)
-{
- unsigned long found, flags;
- struct dma_chan_ref *master_ref, *ref;
- enum dma_state_client ack = DMA_DUP; /* default: take no action */
-
- switch (state) {
- case DMA_RESOURCE_AVAILABLE:
- found = 0;
- rcu_read_lock();
- list_for_each_entry_rcu(ref, &async_tx_master_list, node)
- if (ref->chan == chan) {
- found = 1;
- break;
- }
- rcu_read_unlock();
-
- pr_debug("async_tx: dma resource available [%s]\n",
- found ? "old" : "new");
-
- if (!found)
- ack = DMA_ACK;
- else
- break;
-
- /* add the channel to the generic management list */
- master_ref = kmalloc(sizeof(*master_ref), GFP_KERNEL);
- if (master_ref) {
- /* keep a reference until async_tx is unloaded */
- dma_chan_get(chan);
- init_dma_chan_ref(master_ref, chan);
- spin_lock_irqsave(&async_tx_lock, flags);
- list_add_tail_rcu(&master_ref->node,
- &async_tx_master_list);
- spin_unlock_irqrestore(&async_tx_lock,
- flags);
- } else {
- printk(KERN_WARNING "async_tx: unable to create"
- " new master entry in response to"
- " a DMA_RESOURCE_ADDED event"
- " (-ENOMEM)\n");
- return 0;
- }
-
- async_tx_rebalance();
- break;
- case DMA_RESOURCE_REMOVED:
- found = 0;
- spin_lock_irqsave(&async_tx_lock, flags);
- list_for_each_entry(ref, &async_tx_master_list, node)
- if (ref->chan == chan) {
- /* permit backing devices to go away */
- dma_chan_put(ref->chan);
- list_del_rcu(&ref->node);
- call_rcu(&ref->rcu, free_dma_chan_ref);
- found = 1;
- break;
- }
- spin_unlock_irqrestore(&async_tx_lock, flags);
-
- pr_debug("async_tx: dma resource removed [%s]\n",
- found ? "ours" : "not ours");
-
- if (found)
- ack = DMA_ACK;
- else
- break;
-
- async_tx_rebalance();
- break;
- case DMA_RESOURCE_SUSPEND:
- case DMA_RESOURCE_RESUME:
- printk(KERN_WARNING "async_tx: does not support dma channel"
- " suspend/resume\n");
- break;
- default:
- BUG();
- }
-
- return ack;
-}
-
-static int __init
-async_tx_init(void)
+static int __init async_tx_init(void)
{
- enum dma_transaction_type cap;
-
- spin_lock_init(&async_tx_lock);
- bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
-
- /* an interrupt will never be an explicit operation type.
- * clearing this bit prevents allocation to a slot in 'channel_table'
- */
- clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
-
- for_each_dma_cap_mask(cap, dma_cap_mask_all) {
- channel_table[cap] = alloc_percpu(struct chan_ref_percpu);
- if (!channel_table[cap])
- goto err;
- }
-
- channel_table_initialized = 1;
- dma_async_client_register(&async_tx_dma);
- dma_async_client_chan_request(&async_tx_dma);
+ dmaengine_get();
printk(KERN_INFO "async_tx: api initialized (async)\n");
return 0;
-err:
- printk(KERN_ERR "async_tx: initialization failure\n");
-
- while (--cap >= 0)
- free_percpu(channel_table[cap]);
-
- return 1;
}
static void __exit async_tx_exit(void)
{
- enum dma_transaction_type cap;
-
- channel_table_initialized = 0;
-
- for_each_dma_cap_mask(cap, dma_cap_mask_all)
- if (channel_table[cap])
- free_percpu(channel_table[cap]);
-
- dma_async_client_unregister(&async_tx_dma);
+ dmaengine_put();
}
/**
{
/* see if we can keep the chain on one channel */
if (depend_tx &&
- dma_has_cap(tx_type, depend_tx->chan->device->cap_mask))
+ dma_has_cap(tx_type, depend_tx->chan->device->cap_mask))
return depend_tx->chan;
- else if (likely(channel_table_initialized)) {
- struct dma_chan_ref *ref;
- int cpu = get_cpu();
- ref = per_cpu_ptr(channel_table[tx_type], cpu)->ref;
- put_cpu();
- return ref ? ref->chan : NULL;
- } else
- return NULL;
+ return dma_find_channel(tx_type);
}
EXPORT_SYMBOL_GPL(__async_tx_find_channel);
#else
dca_sysfs_exit();
}
-subsys_initcall(dca_init);
+arch_initcall(dca_init);
module_exit(dca_exit);
config INTEL_IOP_ADMA
tristate "Intel IOP ADMA support"
depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX
- select ASYNC_CORE
select DMA_ENGINE
help
Enable support for the Intel(R) IOP Series RAID engines.
config MV_XOR
bool "Marvell XOR engine support"
depends on PLAT_ORION
- select ASYNC_CORE
select DMA_ENGINE
---help---
Enable support for the Marvell XOR engine.
*
* LOCKING:
*
- * The subsystem keeps two global lists, dma_device_list and dma_client_list.
- * Both of these are protected by a mutex, dma_list_mutex.
+ * The subsystem keeps a global list of dma_device structs it is protected by a
+ * mutex, dma_list_mutex.
+ *
+ * A subsystem can get access to a channel by calling dmaengine_get() followed
+ * by dma_find_channel(), or if it has need for an exclusive channel it can call
+ * dma_request_channel(). Once a channel is allocated a reference is taken
+ * against its corresponding driver to disable removal.
*
* Each device has a channels list, which runs unlocked but is never modified
* once the device is registered, it's just setup by the driver.
*
- * Each client is responsible for keeping track of the channels it uses. See
- * the definition of dma_event_callback in dmaengine.h.
- *
- * Each device has a kref, which is initialized to 1 when the device is
- * registered. A kref_get is done for each device registered. When the
- * device is released, the corresponding kref_put is done in the release
- * method. Every time one of the device's channels is allocated to a client,
- * a kref_get occurs. When the channel is freed, the corresponding kref_put
- * happens. The device's release function does a completion, so
- * unregister_device does a remove event, device_unregister, a kref_put
- * for the first reference, then waits on the completion for all other
- * references to finish.
- *
- * Each channel has an open-coded implementation of Rusty Russell's "bigref,"
- * with a kref and a per_cpu local_t. A dma_chan_get is called when a client
- * signals that it wants to use a channel, and dma_chan_put is called when
- * a channel is removed or a client using it is unregistered. A client can
- * take extra references per outstanding transaction, as is the case with
- * the NET DMA client. The release function does a kref_put on the device.
- * -ChrisL, DanW
+ * See Documentation/dmaengine.txt for more details
*/
#include <linux/init.h>
#include <linux/rcupdate.h>
#include <linux/mutex.h>
#include <linux/jiffies.h>
+#include <linux/rculist.h>
+#include <linux/idr.h>
static DEFINE_MUTEX(dma_list_mutex);
static LIST_HEAD(dma_device_list);
-static LIST_HEAD(dma_client_list);
+static long dmaengine_ref_count;
+static struct idr dma_idr;
/* --- sysfs implementation --- */
+/**
+ * dev_to_dma_chan - convert a device pointer to the its sysfs container object
+ * @dev - device node
+ *
+ * Must be called under dma_list_mutex
+ */
+static struct dma_chan *dev_to_dma_chan(struct device *dev)
+{
+ struct dma_chan_dev *chan_dev;
+
+ chan_dev = container_of(dev, typeof(*chan_dev), device);
+ return chan_dev->chan;
+}
+
static ssize_t show_memcpy_count(struct device *dev, struct device_attribute *attr, char *buf)
{
- struct dma_chan *chan = to_dma_chan(dev);
+ struct dma_chan *chan;
unsigned long count = 0;
int i;
+ int err;
- for_each_possible_cpu(i)
- count += per_cpu_ptr(chan->local, i)->memcpy_count;
+ mutex_lock(&dma_list_mutex);
+ chan = dev_to_dma_chan(dev);
+ if (chan) {
+ for_each_possible_cpu(i)
+ count += per_cpu_ptr(chan->local, i)->memcpy_count;
+ err = sprintf(buf, "%lu\n", count);
+ } else
+ err = -ENODEV;
+ mutex_unlock(&dma_list_mutex);
- return sprintf(buf, "%lu\n", count);
+ return err;
}
static ssize_t show_bytes_transferred(struct device *dev, struct device_attribute *attr,
char *buf)
{
- struct dma_chan *chan = to_dma_chan(dev);
+ struct dma_chan *chan;
unsigned long count = 0;
int i;
+ int err;
- for_each_possible_cpu(i)
- count += per_cpu_ptr(chan->local, i)->bytes_transferred;
+ mutex_lock(&dma_list_mutex);
+ chan = dev_to_dma_chan(dev);
+ if (chan) {
+ for_each_possible_cpu(i)
+ count += per_cpu_ptr(chan->local, i)->bytes_transferred;
+ err = sprintf(buf, "%lu\n", count);
+ } else
+ err = -ENODEV;
+ mutex_unlock(&dma_list_mutex);
- return sprintf(buf, "%lu\n", count);
+ return err;
}
static ssize_t show_in_use(struct device *dev, struct device_attribute *attr, char *buf)
{
- struct dma_chan *chan = to_dma_chan(dev);
- int in_use = 0;
-
- if (unlikely(chan->slow_ref) &&
- atomic_read(&chan->refcount.refcount) > 1)
- in_use = 1;
- else {
- if (local_read(&(per_cpu_ptr(chan->local,
- get_cpu())->refcount)) > 0)
- in_use = 1;
- put_cpu();
- }
+ struct dma_chan *chan;
+ int err;
- return sprintf(buf, "%d\n", in_use);
+ mutex_lock(&dma_list_mutex);
+ chan = dev_to_dma_chan(dev);
+ if (chan)
+ err = sprintf(buf, "%d\n", chan->client_count);
+ else
+ err = -ENODEV;
+ mutex_unlock(&dma_list_mutex);
+
+ return err;
}
static struct device_attribute dma_attrs[] = {
__ATTR_NULL
};
-static void dma_async_device_cleanup(struct kref *kref);
-
-static void dma_dev_release(struct device *dev)
+static void chan_dev_release(struct device *dev)
{
- struct dma_chan *chan = to_dma_chan(dev);
- kref_put(&chan->device->refcount, dma_async_device_cleanup);
+ struct dma_chan_dev *chan_dev;
+
+ chan_dev = container_of(dev, typeof(*chan_dev), device);
+ if (atomic_dec_and_test(chan_dev->idr_ref)) {
+ mutex_lock(&dma_list_mutex);
+ idr_remove(&dma_idr, chan_dev->dev_id);
+ mutex_unlock(&dma_list_mutex);
+ kfree(chan_dev->idr_ref);
+ }
+ kfree(chan_dev);
}
static struct class dma_devclass = {
.name = "dma",
.dev_attrs = dma_attrs,
- .dev_release = dma_dev_release,
+ .dev_release = chan_dev_release,
};
/* --- client and device registration --- */
-#define dma_chan_satisfies_mask(chan, mask) \
- __dma_chan_satisfies_mask((chan), &(mask))
+#define dma_device_satisfies_mask(device, mask) \
+ __dma_device_satisfies_mask((device), &(mask))
static int
-__dma_chan_satisfies_mask(struct dma_chan *chan, dma_cap_mask_t *want)
+__dma_device_satisfies_mask(struct dma_device *device, dma_cap_mask_t *want)
{
dma_cap_mask_t has;
- bitmap_and(has.bits, want->bits, chan->device->cap_mask.bits,
+ bitmap_and(has.bits, want->bits, device->cap_mask.bits,
DMA_TX_TYPE_END);
return bitmap_equal(want->bits, has.bits, DMA_TX_TYPE_END);
}
+static struct module *dma_chan_to_owner(struct dma_chan *chan)
+{
+ return chan->device->dev->driver->owner;
+}
+
/**
- * dma_client_chan_alloc - try to allocate channels to a client
- * @client: &dma_client
+ * balance_ref_count - catch up the channel reference count
+ * @chan - channel to balance ->client_count versus dmaengine_ref_count
*
- * Called with dma_list_mutex held.
+ * balance_ref_count must be called under dma_list_mutex
*/
-static void dma_client_chan_alloc(struct dma_client *client)
+static void balance_ref_count(struct dma_chan *chan)
{
- struct dma_device *device;
- struct dma_chan *chan;
- int desc; /* allocated descriptor count */
- enum dma_state_client ack;
+ struct module *owner = dma_chan_to_owner(chan);
- /* Find a channel */
- list_for_each_entry(device, &dma_device_list, global_node) {
- /* Does the client require a specific DMA controller? */
- if (client->slave && client->slave->dma_dev
- && client->slave->dma_dev != device->dev)
- continue;
+ while (chan->client_count < dmaengine_ref_count) {
+ __module_get(owner);
+ chan->client_count++;
+ }
+}
- list_for_each_entry(chan, &device->channels, device_node) {
- if (!dma_chan_satisfies_mask(chan, client->cap_mask))
- continue;
+/**
+ * dma_chan_get - try to grab a dma channel's parent driver module
+ * @chan - channel to grab
+ *
+ * Must be called under dma_list_mutex
+ */
+static int dma_chan_get(struct dma_chan *chan)
+{
+ int err = -ENODEV;
+ struct module *owner = dma_chan_to_owner(chan);
+
+ if (chan->client_count) {
+ __module_get(owner);
+ err = 0;
+ } else if (try_module_get(owner))
+ err = 0;
+
+ if (err == 0)
+ chan->client_count++;
+
+ /* allocate upon first client reference */
+ if (chan->client_count == 1 && err == 0) {
+ int desc_cnt = chan->device->device_alloc_chan_resources(chan);
+
+ if (desc_cnt < 0) {
+ err = desc_cnt;
+ chan->client_count = 0;
+ module_put(owner);
+ } else if (!dma_has_cap(DMA_PRIVATE, chan->device->cap_mask))
+ balance_ref_count(chan);
+ }
- desc = chan->device->device_alloc_chan_resources(
- chan, client);
- if (desc >= 0) {
- ack = client->event_callback(client,
- chan,
- DMA_RESOURCE_AVAILABLE);
+ return err;
+}
- /* we are done once this client rejects
- * an available resource
- */
- if (ack == DMA_ACK) {
- dma_chan_get(chan);
- chan->client_count++;
- } else if (ack == DMA_NAK)
- return;
- }
- }
- }
+/**
+ * dma_chan_put - drop a reference to a dma channel's parent driver module
+ * @chan - channel to release
+ *
+ * Must be called under dma_list_mutex
+ */
+static void dma_chan_put(struct dma_chan *chan)
+{
+ if (!chan->client_count)
+ return; /* this channel failed alloc_chan_resources */
+ chan->client_count--;
+ module_put(dma_chan_to_owner(chan));
+ if (chan->client_count == 0)
+ chan->device->device_free_chan_resources(chan);
}
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie)
EXPORT_SYMBOL(dma_sync_wait);
/**
- * dma_chan_cleanup - release a DMA channel's resources
- * @kref: kernel reference structure that contains the DMA channel device
+ * dma_cap_mask_all - enable iteration over all operation types
+ */
+static dma_cap_mask_t dma_cap_mask_all;
+
+/**
+ * dma_chan_tbl_ent - tracks channel allocations per core/operation
+ * @chan - associated channel for this entry
+ */
+struct dma_chan_tbl_ent {
+ struct dma_chan *chan;
+};
+
+/**
+ * channel_table - percpu lookup table for memory-to-memory offload providers
*/
-void dma_chan_cleanup(struct kref *kref)
+static struct dma_chan_tbl_ent *channel_table[DMA_TX_TYPE_END];
+
+static int __init dma_channel_table_init(void)
{
- struct dma_chan *chan = container_of(kref, struct dma_chan, refcount);
- chan->device->device_free_chan_resources(chan);
- kref_put(&chan->device->refcount, dma_async_device_cleanup);
+ enum dma_transaction_type cap;
+ int err = 0;
+
+ bitmap_fill(dma_cap_mask_all.bits, DMA_TX_TYPE_END);
+
+ /* 'interrupt', 'private', and 'slave' are channel capabilities,
+ * but are not associated with an operation so they do not need
+ * an entry in the channel_table
+ */
+ clear_bit(DMA_INTERRUPT, dma_cap_mask_all.bits);
+ clear_bit(DMA_PRIVATE, dma_cap_mask_all.bits);
+ clear_bit(DMA_SLAVE, dma_cap_mask_all.bits);
+
+ for_each_dma_cap_mask(cap, dma_cap_mask_all) {
+ channel_table[cap] = alloc_percpu(struct dma_chan_tbl_ent);
+ if (!channel_table[cap]) {
+ err = -ENOMEM;
+ break;
+ }
+ }
+
+ if (err) {
+ pr_err("dmaengine: initialization failure\n");
+ for_each_dma_cap_mask(cap, dma_cap_mask_all)
+ if (channel_table[cap])
+ free_percpu(channel_table[cap]);
+ }
+
+ return err;
}
-EXPORT_SYMBOL(dma_chan_cleanup);
+arch_initcall(dma_channel_table_init);
-static void dma_chan_free_rcu(struct rcu_head *rcu)
+/**
+ * dma_find_channel - find a channel to carry out the operation
+ * @tx_type: transaction type
+ */
+struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type)
{
- struct dma_chan *chan = container_of(rcu, struct dma_chan, rcu);
- int bias = 0x7FFFFFFF;
- int i;
- for_each_possible_cpu(i)
- bias -= local_read(&per_cpu_ptr(chan->local, i)->refcount);
- atomic_sub(bias, &chan->refcount.refcount);
- kref_put(&chan->refcount, dma_chan_cleanup);
+ struct dma_chan *chan;
+ int cpu;
+
+ WARN_ONCE(dmaengine_ref_count == 0,
+ "client called %s without a reference", __func__);
+
+ cpu = get_cpu();
+ chan = per_cpu_ptr(channel_table[tx_type], cpu)->chan;
+ put_cpu();
+
+ return chan;
}
+EXPORT_SYMBOL(dma_find_channel);
-static void dma_chan_release(struct dma_chan *chan)
+/**
+ * dma_issue_pending_all - flush all pending operations across all channels
+ */
+void dma_issue_pending_all(void)
{
- atomic_add(0x7FFFFFFF, &chan->refcount.refcount);
- chan->slow_ref = 1;
- call_rcu(&chan->rcu, dma_chan_free_rcu);
+ struct dma_device *device;
+ struct dma_chan *chan;
+
+ WARN_ONCE(dmaengine_ref_count == 0,
+ "client called %s without a reference", __func__);
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(device, &dma_device_list, global_node) {
+ if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ continue;
+ list_for_each_entry(chan, &device->channels, device_node)
+ if (chan->client_count)
+ device->device_issue_pending(chan);
+ }
+ rcu_read_unlock();
}
+EXPORT_SYMBOL(dma_issue_pending_all);
/**
- * dma_chans_notify_available - broadcast available channels to the clients
+ * nth_chan - returns the nth channel of the given capability
+ * @cap: capability to match
+ * @n: nth channel desired
+ *
+ * Defaults to returning the channel with the desired capability and the
+ * lowest reference count when 'n' cannot be satisfied. Must be called
+ * under dma_list_mutex.
*/
-static void dma_clients_notify_available(void)
+static struct dma_chan *nth_chan(enum dma_transaction_type cap, int n)
{
- struct dma_client *client;
+ struct dma_device *device;
+ struct dma_chan *chan;
+ struct dma_chan *ret = NULL;
+ struct dma_chan *min = NULL;
- mutex_lock(&dma_list_mutex);
+ list_for_each_entry(device, &dma_device_list, global_node) {
+ if (!dma_has_cap(cap, device->cap_mask) ||
+ dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ continue;
+ list_for_each_entry(chan, &device->channels, device_node) {
+ if (!chan->client_count)
+ continue;
+ if (!min)
+ min = chan;
+ else if (chan->table_count < min->table_count)
+ min = chan;
+
+ if (n-- == 0) {
+ ret = chan;
+ break; /* done */
+ }
+ }
+ if (ret)
+ break; /* done */
+ }
- list_for_each_entry(client, &dma_client_list, global_node)
- dma_client_chan_alloc(client);
+ if (!ret)
+ ret = min;
- mutex_unlock(&dma_list_mutex);
+ if (ret)
+ ret->table_count++;
+
+ return ret;
}
/**
- * dma_chans_notify_available - tell the clients that a channel is going away
- * @chan: channel on its way out
+ * dma_channel_rebalance - redistribute the available channels
+ *
+ * Optimize for cpu isolation (each cpu gets a dedicated channel for an
+ * operation type) in the SMP case, and operation isolation (avoid
+ * multi-tasking channels) in the non-SMP case. Must be called under
+ * dma_list_mutex.
*/
-static void dma_clients_notify_removed(struct dma_chan *chan)
+static void dma_channel_rebalance(void)
{
- struct dma_client *client;
- enum dma_state_client ack;
+ struct dma_chan *chan;
+ struct dma_device *device;
+ int cpu;
+ int cap;
+ int n;
- mutex_lock(&dma_list_mutex);
+ /* undo the last distribution */
+ for_each_dma_cap_mask(cap, dma_cap_mask_all)
+ for_each_possible_cpu(cpu)
+ per_cpu_ptr(channel_table[cap], cpu)->chan = NULL;
+
+ list_for_each_entry(device, &dma_device_list, global_node) {
+ if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ continue;
+ list_for_each_entry(chan, &device->channels, device_node)
+ chan->table_count = 0;
+ }
- list_for_each_entry(client, &dma_client_list, global_node) {
- ack = client->event_callback(client, chan,
- DMA_RESOURCE_REMOVED);
+ /* don't populate the channel_table if no clients are available */
+ if (!dmaengine_ref_count)
+ return;
- /* client was holding resources for this channel so
- * free it
- */
- if (ack == DMA_ACK) {
- dma_chan_put(chan);
- chan->client_count--;
+ /* redistribute available channels */
+ n = 0;
+ for_each_dma_cap_mask(cap, dma_cap_mask_all)
+ for_each_online_cpu(cpu) {
+ if (num_possible_cpus() > 1)
+ chan = nth_chan(cap, n++);
+ else
+ chan = nth_chan(cap, -1);
+
+ per_cpu_ptr(channel_table[cap], cpu)->chan = chan;
+ }
+}
+
+static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_device *dev,
+ dma_filter_fn fn, void *fn_param)
+{
+ struct dma_chan *chan;
+
+ if (!__dma_device_satisfies_mask(dev, mask)) {
+ pr_debug("%s: wrong capabilities\n", __func__);
+ return NULL;
+ }
+ /* devices with multiple channels need special handling as we need to
+ * ensure that all channels are either private or public.
+ */
+ if (dev->chancnt > 1 && !dma_has_cap(DMA_PRIVATE, dev->cap_mask))
+ list_for_each_entry(chan, &dev->channels, device_node) {
+ /* some channels are already publicly allocated */
+ if (chan->client_count)
+ return NULL;
}
+
+ list_for_each_entry(chan, &dev->channels, device_node) {
+ if (chan->client_count) {
+ pr_debug("%s: %s busy\n",
+ __func__, dma_chan_name(chan));
+ continue;
+ }
+ if (fn && !fn(chan, fn_param)) {
+ pr_debug("%s: %s filter said false\n",
+ __func__, dma_chan_name(chan));
+ continue;
+ }
+ return chan;
}
- mutex_unlock(&dma_list_mutex);
+ return NULL;
}
/**
- * dma_async_client_register - register a &dma_client
- * @client: ptr to a client structure with valid 'event_callback' and 'cap_mask'
+ * dma_request_channel - try to allocate an exclusive channel
+ * @mask: capabilities that the channel must satisfy
+ * @fn: optional callback to disposition available channels
+ * @fn_param: opaque parameter to pass to dma_filter_fn
*/
-void dma_async_client_register(struct dma_client *client)
+struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param)
{
- /* validate client data */
- BUG_ON(dma_has_cap(DMA_SLAVE, client->cap_mask) &&
- !client->slave);
+ struct dma_device *device, *_d;
+ struct dma_chan *chan = NULL;
+ int err;
+ /* Find a channel */
+ mutex_lock(&dma_list_mutex);
+ list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
+ chan = private_candidate(mask, device, fn, fn_param);
+ if (chan) {
+ /* Found a suitable channel, try to grab, prep, and
+ * return it. We first set DMA_PRIVATE to disable
+ * balance_ref_count as this channel will not be
+ * published in the general-purpose allocator
+ */
+ dma_cap_set(DMA_PRIVATE, device->cap_mask);
+ err = dma_chan_get(chan);
+
+ if (err == -ENODEV) {
+ pr_debug("%s: %s module removed\n", __func__,
+ dma_chan_name(chan));
+ list_del_rcu(&device->global_node);
+ } else if (err)
+ pr_err("dmaengine: failed to get %s: (%d)\n",
+ dma_chan_name(chan), err);
+ else
+ break;
+ chan = NULL;
+ }
+ }
+ mutex_unlock(&dma_list_mutex);
+
+ pr_debug("%s: %s (%s)\n", __func__, chan ? "success" : "fail",
+ chan ? dma_chan_name(chan) : NULL);
+
+ return chan;
+}
+EXPORT_SYMBOL_GPL(__dma_request_channel);
+
+void dma_release_channel(struct dma_chan *chan)
+{
mutex_lock(&dma_list_mutex);
- list_add_tail(&client->global_node, &dma_client_list);
+ WARN_ONCE(chan->client_count != 1,
+ "chan reference count %d != 1\n", chan->client_count);
+ dma_chan_put(chan);
mutex_unlock(&dma_list_mutex);
}
-EXPORT_SYMBOL(dma_async_client_register);
+EXPORT_SYMBOL_GPL(dma_release_channel);
/**
- * dma_async_client_unregister - unregister a client and free the &dma_client
- * @client: &dma_client to free
- *
- * Force frees any allocated DMA channels, frees the &dma_client memory
+ * dmaengine_get - register interest in dma_channels
*/
-void dma_async_client_unregister(struct dma_client *client)
+void dmaengine_get(void)
{
- struct dma_device *device;
+ struct dma_device *device, *_d;
struct dma_chan *chan;
- enum dma_state_client ack;
-
- if (!client)
- return;
+ int err;
mutex_lock(&dma_list_mutex);
- /* free all channels the client is holding */
- list_for_each_entry(device, &dma_device_list, global_node)
- list_for_each_entry(chan, &device->channels, device_node) {
- ack = client->event_callback(client, chan,
- DMA_RESOURCE_REMOVED);
+ dmaengine_ref_count++;
- if (ack == DMA_ACK) {
- dma_chan_put(chan);
- chan->client_count--;
- }
+ /* try to grab channels */
+ list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
+ if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ continue;
+ list_for_each_entry(chan, &device->channels, device_node) {
+ err = dma_chan_get(chan);
+ if (err == -ENODEV) {
+ /* module removed before we could use it */
+ list_del_rcu(&device->global_node);
+ break;
+ } else if (err)
+ pr_err("dmaengine: failed to get %s: (%d)\n",
+ dma_chan_name(chan), err);
}
+ }
- list_del(&client->global_node);
+ /* if this is the first reference and there were channels
+ * waiting we need to rebalance to get those channels
+ * incorporated into the channel table
+ */
+ if (dmaengine_ref_count == 1)
+ dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
}
-EXPORT_SYMBOL(dma_async_client_unregister);
+EXPORT_SYMBOL(dmaengine_get);
/**
- * dma_async_client_chan_request - send all available channels to the
- * client that satisfy the capability mask
- * @client - requester
+ * dmaengine_put - let dma drivers be removed when ref_count == 0
*/
-void dma_async_client_chan_request(struct dma_client *client)
+void dmaengine_put(void)
{
+ struct dma_device *device;
+ struct dma_chan *chan;
+
mutex_lock(&dma_list_mutex);
- dma_client_chan_alloc(client);
+ dmaengine_ref_count--;
+ BUG_ON(dmaengine_ref_count < 0);
+ /* drop channel references */
+ list_for_each_entry(device, &dma_device_list, global_node) {
+ if (dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ continue;
+ list_for_each_entry(chan, &device->channels, device_node)
+ dma_chan_put(chan);
+ }
mutex_unlock(&dma_list_mutex);
}
-EXPORT_SYMBOL(dma_async_client_chan_request);
+EXPORT_SYMBOL(dmaengine_put);
/**
* dma_async_device_register - registers DMA devices found
*/
int dma_async_device_register(struct dma_device *device)
{
- static int id;
int chancnt = 0, rc;
struct dma_chan* chan;
+ atomic_t *idr_ref;
if (!device)
return -ENODEV;
BUG_ON(!device->device_issue_pending);
BUG_ON(!device->dev);
- init_completion(&device->done);
- kref_init(&device->refcount);
-
+ idr_ref = kmalloc(sizeof(*idr_ref), GFP_KERNEL);
+ if (!idr_ref)
+ return -ENOMEM;
+ atomic_set(idr_ref, 0);
+ idr_retry:
+ if (!idr_pre_get(&dma_idr, GFP_KERNEL))
+ return -ENOMEM;
mutex_lock(&dma_list_mutex);
- device->dev_id = id++;
+ rc = idr_get_new(&dma_idr, NULL, &device->dev_id);
mutex_unlock(&dma_list_mutex);
+ if (rc == -EAGAIN)
+ goto idr_retry;
+ else if (rc != 0)
+ return rc;
/* represent channels in sysfs. Probably want devs too */
list_for_each_entry(chan, &device->channels, device_node) {
chan->local = alloc_percpu(typeof(*chan->local));
if (chan->local == NULL)
continue;
+ chan->dev = kzalloc(sizeof(*chan->dev), GFP_KERNEL);
+ if (chan->dev == NULL) {
+ free_percpu(chan->local);
+ continue;
+ }
chan->chan_id = chancnt++;
- chan->dev.class = &dma_devclass;
- chan->dev.parent = device->dev;
- dev_set_name(&chan->dev, "dma%dchan%d",
+ chan->dev->device.class = &dma_devclass;
+ chan->dev->device.parent = device->dev;
+ chan->dev->chan = chan;
+ chan->dev->idr_ref = idr_ref;
+ chan->dev->dev_id = device->dev_id;
+ atomic_inc(idr_ref);
+ dev_set_name(&chan->dev->device, "dma%dchan%d",
device->dev_id, chan->chan_id);
- rc = device_register(&chan->dev);
+ rc = device_register(&chan->dev->device);
if (rc) {
- chancnt--;
free_percpu(chan->local);
chan->local = NULL;
goto err_out;
}
-
- /* One for the channel, one of the class device */
- kref_get(&device->refcount);
- kref_get(&device->refcount);
- kref_init(&chan->refcount);
chan->client_count = 0;
- chan->slow_ref = 0;
- INIT_RCU_HEAD(&chan->rcu);
}
+ device->chancnt = chancnt;
mutex_lock(&dma_list_mutex);
- list_add_tail(&device->global_node, &dma_device_list);
+ /* take references on public channels */
+ if (dmaengine_ref_count && !dma_has_cap(DMA_PRIVATE, device->cap_mask))
+ list_for_each_entry(chan, &device->channels, device_node) {
+ /* if clients are already waiting for channels we need
+ * to take references on their behalf
+ */
+ if (dma_chan_get(chan) == -ENODEV) {
+ /* note we can only get here for the first
+ * channel as the remaining channels are
+ * guaranteed to get a reference
+ */
+ rc = -ENODEV;
+ mutex_unlock(&dma_list_mutex);
+ goto err_out;
+ }
+ }
+ list_add_tail_rcu(&device->global_node, &dma_device_list);
+ dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
- dma_clients_notify_available();
-
return 0;
err_out:
list_for_each_entry(chan, &device->channels, device_node) {
if (chan->local == NULL)
continue;
- kref_put(&device->refcount, dma_async_device_cleanup);
- device_unregister(&chan->dev);
- chancnt--;
+ mutex_lock(&dma_list_mutex);
+ chan->dev->chan = NULL;
+ mutex_unlock(&dma_list_mutex);
+ device_unregister(&chan->dev->device);
free_percpu(chan->local);
}
return rc;
EXPORT_SYMBOL(dma_async_device_register);
/**
- * dma_async_device_cleanup - function called when all references are released
- * @kref: kernel reference object
- */
-static void dma_async_device_cleanup(struct kref *kref)
-{
- struct dma_device *device;
-
- device = container_of(kref, struct dma_device, refcount);
- complete(&device->done);
-}
-
-/**
- * dma_async_device_unregister - unregisters DMA devices
+ * dma_async_device_unregister - unregister a DMA device
* @device: &dma_device
+ *
+ * This routine is called by dma driver exit routines, dmaengine holds module
+ * references to prevent it being called while channels are in use.
*/
void dma_async_device_unregister(struct dma_device *device)
{
struct dma_chan *chan;
mutex_lock(&dma_list_mutex);
- list_del(&device->global_node);
+ list_del_rcu(&device->global_node);
+ dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
list_for_each_entry(chan, &device->channels, device_node) {
- dma_clients_notify_removed(chan);
- device_unregister(&chan->dev);
- dma_chan_release(chan);
+ WARN_ONCE(chan->client_count,
+ "%s called while %d clients hold a reference\n",
+ __func__, chan->client_count);
+ mutex_lock(&dma_list_mutex);
+ chan->dev->chan = NULL;
+ mutex_unlock(&dma_list_mutex);
+ device_unregister(&chan->dev->device);
}
-
- kref_put(&device->refcount, dma_async_device_cleanup);
- wait_for_completion(&device->done);
}
EXPORT_SYMBOL(dma_async_device_unregister);
}
EXPORT_SYMBOL(dma_async_tx_descriptor_init);
+/* dma_wait_for_async_tx - spin wait for a transaction to complete
+ * @tx: in-flight transaction to wait on
+ *
+ * This routine assumes that tx was obtained from a call to async_memcpy,
+ * async_xor, async_memset, etc which ensures that tx is "in-flight" (prepped
+ * and submitted). Walking the parent chain is only meant to cover for DMA
+ * drivers that do not implement the DMA_INTERRUPT capability and may race with
+ * the driver's descriptor cleanup routine.
+ */
+enum dma_status
+dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
+{
+ enum dma_status status;
+ struct dma_async_tx_descriptor *iter;
+ struct dma_async_tx_descriptor *parent;
+
+ if (!tx)
+ return DMA_SUCCESS;
+
+ WARN_ONCE(tx->parent, "%s: speculatively walking dependency chain for"
+ " %s\n", __func__, dma_chan_name(tx->chan));
+
+ /* poll through the dependency chain, return when tx is complete */
+ do {
+ iter = tx;
+
+ /* find the root of the unsubmitted dependency chain */
+ do {
+ parent = iter->parent;
+ if (!parent)
+ break;
+ else
+ iter = parent;
+ } while (parent);
+
+ /* there is a small window for ->parent == NULL and
+ * ->cookie == -EBUSY
+ */
+ while (iter->cookie == -EBUSY)
+ cpu_relax();
+
+ status = dma_sync_wait(iter->chan, iter->cookie);
+ } while (status == DMA_IN_PROGRESS || (iter != tx));
+
+ return status;
+}
+EXPORT_SYMBOL_GPL(dma_wait_for_async_tx);
+
+/* dma_run_dependencies - helper routine for dma drivers to process
+ * (start) dependent operations on their target channel
+ * @tx: transaction with dependencies
+ */
+void dma_run_dependencies(struct dma_async_tx_descriptor *tx)
+{
+ struct dma_async_tx_descriptor *dep = tx->next;
+ struct dma_async_tx_descriptor *dep_next;
+ struct dma_chan *chan;
+
+ if (!dep)
+ return;
+
+ chan = dep->chan;
+
+ /* keep submitting up until a channel switch is detected
+ * in that case we will be called again as a result of
+ * processing the interrupt from async_tx_channel_switch
+ */
+ for (; dep; dep = dep_next) {
+ spin_lock_bh(&dep->lock);
+ dep->parent = NULL;
+ dep_next = dep->next;
+ if (dep_next && dep_next->chan == chan)
+ dep->next = NULL; /* ->next will be submitted */
+ else
+ dep_next = NULL; /* submit current dep and terminate */
+ spin_unlock_bh(&dep->lock);
+
+ dep->tx_submit(dep);
+ }
+
+ chan->device->device_issue_pending(chan);
+}
+EXPORT_SYMBOL_GPL(dma_run_dependencies);
+
static int __init dma_bus_init(void)
{
+ idr_init(&dma_idr);
mutex_init(&dma_list_mutex);
return class_register(&dma_devclass);
}
-subsys_initcall(dma_bus_init);
+arch_initcall(dma_bus_init);
+
static unsigned int max_channels;
module_param(max_channels, uint, S_IRUGO);
-MODULE_PARM_DESC(nr_channels,
+MODULE_PARM_DESC(max_channels,
"Maximum number of channels to use (default: all)");
/*
/*
* These are protected by dma_list_mutex since they're only used by
- * the DMA client event callback
+ * the DMA filter function callback
*/
static LIST_HEAD(dmatest_channels);
static unsigned int nr_channels;
{
if (test_channel[0] == '\0')
return true;
- return strcmp(dev_name(&chan->dev), test_channel) == 0;
+ return strcmp(dma_chan_name(chan), test_channel) == 0;
}
static bool dmatest_match_device(struct dma_device *device)
smp_rmb();
chan = thread->chan;
- dma_chan_get(chan);
while (!kthread_should_stop()) {
total_tests++;
}
ret = 0;
- dma_chan_put(chan);
kfree(thread->dstbuf);
err_dstbuf:
kfree(thread->srcbuf);
kfree(dtc);
}
-static enum dma_state_client dmatest_add_channel(struct dma_chan *chan)
+static int dmatest_add_channel(struct dma_chan *chan)
{
struct dmatest_chan *dtc;
struct dmatest_thread *thread;
unsigned int i;
- /* Have we already been told about this channel? */
- list_for_each_entry(dtc, &dmatest_channels, node)
- if (dtc->chan == chan)
- return DMA_DUP;
-
dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
if (!dtc) {
- pr_warning("dmatest: No memory for %s\n", dev_name(&chan->dev));
- return DMA_NAK;
+ pr_warning("dmatest: No memory for %s\n", dma_chan_name(chan));
+ return -ENOMEM;
}
dtc->chan = chan;
thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
if (!thread) {
pr_warning("dmatest: No memory for %s-test%u\n",
- dev_name(&chan->dev), i);
+ dma_chan_name(chan), i);
break;
}
thread->chan = dtc->chan;
smp_wmb();
thread->task = kthread_run(dmatest_func, thread, "%s-test%u",
- dev_name(&chan->dev), i);
+ dma_chan_name(chan), i);
if (IS_ERR(thread->task)) {
pr_warning("dmatest: Failed to run thread %s-test%u\n",
- dev_name(&chan->dev), i);
+ dma_chan_name(chan), i);
kfree(thread);
break;
}
list_add_tail(&thread->node, &dtc->threads);
}
- pr_info("dmatest: Started %u threads using %s\n", i, dev_name(&chan->dev));
+ pr_info("dmatest: Started %u threads using %s\n", i, dma_chan_name(chan));
list_add_tail(&dtc->node, &dmatest_channels);
nr_channels++;
- return DMA_ACK;
-}
-
-static enum dma_state_client dmatest_remove_channel(struct dma_chan *chan)
-{
- struct dmatest_chan *dtc, *_dtc;
-
- list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) {
- if (dtc->chan == chan) {
- list_del(&dtc->node);
- dmatest_cleanup_channel(dtc);
- pr_debug("dmatest: lost channel %s\n",
- dev_name(&chan->dev));
- return DMA_ACK;
- }
- }
-
- return DMA_DUP;
+ return 0;
}
-/*
- * Start testing threads as new channels are assigned to us, and kill
- * them when the channels go away.
- *
- * When we unregister the client, all channels are removed so this
- * will also take care of cleaning things up when the module is
- * unloaded.
- */
-static enum dma_state_client
-dmatest_event(struct dma_client *client, struct dma_chan *chan,
- enum dma_state state)
+static bool filter(struct dma_chan *chan, void *param)
{
- enum dma_state_client ack = DMA_NAK;
-
- switch (state) {
- case DMA_RESOURCE_AVAILABLE:
- if (!dmatest_match_channel(chan)
- || !dmatest_match_device(chan->device))
- ack = DMA_DUP;
- else if (max_channels && nr_channels >= max_channels)
- ack = DMA_NAK;
- else
- ack = dmatest_add_channel(chan);
- break;
-
- case DMA_RESOURCE_REMOVED:
- ack = dmatest_remove_channel(chan);
- break;
-
- default:
- pr_info("dmatest: Unhandled event %u (%s)\n",
- state, dev_name(&chan->dev));
- break;
- }
-
- return ack;
+ if (!dmatest_match_channel(chan) || !dmatest_match_device(chan->device))
+ return false;
+ else
+ return true;
}
-static struct dma_client dmatest_client = {
- .event_callback = dmatest_event,
-};
-
static int __init dmatest_init(void)
{
- dma_cap_set(DMA_MEMCPY, dmatest_client.cap_mask);
- dma_async_client_register(&dmatest_client);
- dma_async_client_chan_request(&dmatest_client);
+ dma_cap_mask_t mask;
+ struct dma_chan *chan;
+ int err = 0;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_MEMCPY, mask);
+ for (;;) {
+ chan = dma_request_channel(mask, filter, NULL);
+ if (chan) {
+ err = dmatest_add_channel(chan);
+ if (err == 0)
+ continue;
+ else {
+ dma_release_channel(chan);
+ break; /* add_channel failed, punt */
+ }
+ } else
+ break; /* no more channels available */
+ if (max_channels && nr_channels >= max_channels)
+ break; /* we have all we need */
+ }
- return 0;
+ return err;
}
-module_init(dmatest_init);
+/* when compiled-in wait for drivers to load first */
+late_initcall(dmatest_init);
static void __exit dmatest_exit(void)
{
- dma_async_client_unregister(&dmatest_client);
+ struct dmatest_chan *dtc, *_dtc;
+
+ list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) {
+ list_del(&dtc->node);
+ dmatest_cleanup_channel(dtc);
+ pr_debug("dmatest: dropped channel %s\n",
+ dma_chan_name(dtc->chan));
+ dma_release_channel(dtc->chan);
+ }
}
module_exit(dmatest_exit);
* the controller, though.
*/
+static struct device *chan2dev(struct dma_chan *chan)
+{
+ return &chan->dev->device;
+}
+static struct device *chan2parent(struct dma_chan *chan)
+{
+ return chan->dev->device.parent;
+}
+
static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc)
{
return list_entry(dwc->active_list.next, struct dw_desc, desc_node);
ret = desc;
break;
}
- dev_dbg(&dwc->chan.dev, "desc %p not ACKed\n", desc);
+ dev_dbg(chan2dev(&dwc->chan), "desc %p not ACKed\n", desc);
i++;
}
spin_unlock_bh(&dwc->lock);
- dev_vdbg(&dwc->chan.dev, "scanned %u descriptors on freelist\n", i);
+ dev_vdbg(chan2dev(&dwc->chan), "scanned %u descriptors on freelist\n", i);
return ret;
}
struct dw_desc *child;
list_for_each_entry(child, &desc->txd.tx_list, desc_node)
- dma_sync_single_for_cpu(dwc->chan.dev.parent,
+ dma_sync_single_for_cpu(chan2parent(&dwc->chan),
child->txd.phys, sizeof(child->lli),
DMA_TO_DEVICE);
- dma_sync_single_for_cpu(dwc->chan.dev.parent,
+ dma_sync_single_for_cpu(chan2parent(&dwc->chan),
desc->txd.phys, sizeof(desc->lli),
DMA_TO_DEVICE);
}
spin_lock_bh(&dwc->lock);
list_for_each_entry(child, &desc->txd.tx_list, desc_node)
- dev_vdbg(&dwc->chan.dev,
+ dev_vdbg(chan2dev(&dwc->chan),
"moving child desc %p to freelist\n",
child);
list_splice_init(&desc->txd.tx_list, &dwc->free_list);
- dev_vdbg(&dwc->chan.dev, "moving desc %p to freelist\n", desc);
+ dev_vdbg(chan2dev(&dwc->chan), "moving desc %p to freelist\n", desc);
list_add(&desc->desc_node, &dwc->free_list);
spin_unlock_bh(&dwc->lock);
}
/* ASSERT: channel is idle */
if (dma_readl(dw, CH_EN) & dwc->mask) {
- dev_err(&dwc->chan.dev,
+ dev_err(chan2dev(&dwc->chan),
"BUG: Attempted to start non-idle channel\n");
- dev_err(&dwc->chan.dev,
+ dev_err(chan2dev(&dwc->chan),
" SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n",
channel_readl(dwc, SAR),
channel_readl(dwc, DAR),
void *param;
struct dma_async_tx_descriptor *txd = &desc->txd;
- dev_vdbg(&dwc->chan.dev, "descriptor %u complete\n", txd->cookie);
+ dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie);
dwc->completed = txd->cookie;
callback = txd->callback;
* mapped before they were submitted...
*/
if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP))
- dma_unmap_page(dwc->chan.dev.parent, desc->lli.dar, desc->len,
- DMA_FROM_DEVICE);
+ dma_unmap_page(chan2parent(&dwc->chan), desc->lli.dar,
+ desc->len, DMA_FROM_DEVICE);
if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP))
- dma_unmap_page(dwc->chan.dev.parent, desc->lli.sar, desc->len,
- DMA_TO_DEVICE);
+ dma_unmap_page(chan2parent(&dwc->chan), desc->lli.sar,
+ desc->len, DMA_TO_DEVICE);
/*
* The API requires that no submissions are done from a
LIST_HEAD(list);
if (dma_readl(dw, CH_EN) & dwc->mask) {
- dev_err(&dwc->chan.dev,
+ dev_err(chan2dev(&dwc->chan),
"BUG: XFER bit set, but channel not idle!\n");
/* Try to continue after resetting the channel... */
return;
}
- dev_vdbg(&dwc->chan.dev, "scan_descriptors: llp=0x%x\n", llp);
+ dev_vdbg(chan2dev(&dwc->chan), "scan_descriptors: llp=0x%x\n", llp);
list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
if (desc->lli.llp == llp)
dwc_descriptor_complete(dwc, desc);
}
- dev_err(&dwc->chan.dev,
+ dev_err(chan2dev(&dwc->chan),
"BUG: All descriptors done, but channel not idle!\n");
/* Try to continue after resetting the channel... */
static void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_lli *lli)
{
- dev_printk(KERN_CRIT, &dwc->chan.dev,
+ dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
" desc: s0x%x d0x%x l0x%x c0x%x:%x\n",
lli->sar, lli->dar, lli->llp,
lli->ctlhi, lli->ctllo);
* controller flagged an error instead of scribbling over
* random memory locations.
*/
- dev_printk(KERN_CRIT, &dwc->chan.dev,
+ dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
"Bad descriptor submitted for DMA!\n");
- dev_printk(KERN_CRIT, &dwc->chan.dev,
+ dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
" cookie: %d\n", bad_desc->txd.cookie);
dwc_dump_lli(dwc, &bad_desc->lli);
list_for_each_entry(child, &bad_desc->txd.tx_list, desc_node)
* for DMA. But this is hard to do in a race-free manner.
*/
if (list_empty(&dwc->active_list)) {
- dev_vdbg(&tx->chan->dev, "tx_submit: started %u\n",
+ dev_vdbg(chan2dev(tx->chan), "tx_submit: started %u\n",
desc->txd.cookie);
dwc_dostart(dwc, desc);
list_add_tail(&desc->desc_node, &dwc->active_list);
} else {
- dev_vdbg(&tx->chan->dev, "tx_submit: queued %u\n",
+ dev_vdbg(chan2dev(tx->chan), "tx_submit: queued %u\n",
desc->txd.cookie);
list_add_tail(&desc->desc_node, &dwc->queue);
unsigned int dst_width;
u32 ctllo;
- dev_vdbg(&chan->dev, "prep_dma_memcpy d0x%x s0x%x l0x%zx f0x%lx\n",
+ dev_vdbg(chan2dev(chan), "prep_dma_memcpy d0x%x s0x%x l0x%zx f0x%lx\n",
dest, src, len, flags);
if (unlikely(!len)) {
- dev_dbg(&chan->dev, "prep_dma_memcpy: length is zero!\n");
+ dev_dbg(chan2dev(chan), "prep_dma_memcpy: length is zero!\n");
return NULL;
}
first = desc;
} else {
prev->lli.llp = desc->txd.phys;
- dma_sync_single_for_device(chan->dev.parent,
+ dma_sync_single_for_device(chan2parent(chan),
prev->txd.phys, sizeof(prev->lli),
DMA_TO_DEVICE);
list_add_tail(&desc->desc_node,
prev->lli.ctllo |= DWC_CTLL_INT_EN;
prev->lli.llp = 0;
- dma_sync_single_for_device(chan->dev.parent,
+ dma_sync_single_for_device(chan2parent(chan),
prev->txd.phys, sizeof(prev->lli),
DMA_TO_DEVICE);
struct scatterlist *sg;
size_t total_len = 0;
- dev_vdbg(&chan->dev, "prep_dma_slave\n");
+ dev_vdbg(chan2dev(chan), "prep_dma_slave\n");
if (unlikely(!dws || !sg_len))
return NULL;
- reg_width = dws->slave.reg_width;
+ reg_width = dws->reg_width;
prev = first = NULL;
- sg_len = dma_map_sg(chan->dev.parent, sgl, sg_len, direction);
+ sg_len = dma_map_sg(chan2parent(chan), sgl, sg_len, direction);
switch (direction) {
case DMA_TO_DEVICE:
| DWC_CTLL_DST_FIX
| DWC_CTLL_SRC_INC
| DWC_CTLL_FC_M2P);
- reg = dws->slave.tx_reg;
+ reg = dws->tx_reg;
for_each_sg(sgl, sg, sg_len, i) {
struct dw_desc *desc;
u32 len;
desc = dwc_desc_get(dwc);
if (!desc) {
- dev_err(&chan->dev,
+ dev_err(chan2dev(chan),
"not enough descriptors available\n");
goto err_desc_get;
}
first = desc;
} else {
prev->lli.llp = desc->txd.phys;
- dma_sync_single_for_device(chan->dev.parent,
+ dma_sync_single_for_device(chan2parent(chan),
prev->txd.phys,
sizeof(prev->lli),
DMA_TO_DEVICE);
| DWC_CTLL_SRC_FIX
| DWC_CTLL_FC_P2M);
- reg = dws->slave.rx_reg;
+ reg = dws->rx_reg;
for_each_sg(sgl, sg, sg_len, i) {
struct dw_desc *desc;
u32 len;
desc = dwc_desc_get(dwc);
if (!desc) {
- dev_err(&chan->dev,
+ dev_err(chan2dev(chan),
"not enough descriptors available\n");
goto err_desc_get;
}
first = desc;
} else {
prev->lli.llp = desc->txd.phys;
- dma_sync_single_for_device(chan->dev.parent,
+ dma_sync_single_for_device(chan2parent(chan),
prev->txd.phys,
sizeof(prev->lli),
DMA_TO_DEVICE);
prev->lli.ctllo |= DWC_CTLL_INT_EN;
prev->lli.llp = 0;
- dma_sync_single_for_device(chan->dev.parent,
+ dma_sync_single_for_device(chan2parent(chan),
prev->txd.phys, sizeof(prev->lli),
DMA_TO_DEVICE);
spin_unlock_bh(&dwc->lock);
}
-static int dwc_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int dwc_alloc_chan_resources(struct dma_chan *chan)
{
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
struct dw_dma *dw = to_dw_dma(chan->device);
struct dw_desc *desc;
- struct dma_slave *slave;
struct dw_dma_slave *dws;
int i;
u32 cfghi;
u32 cfglo;
- dev_vdbg(&chan->dev, "alloc_chan_resources\n");
-
- /* Channels doing slave DMA can only handle one client. */
- if (dwc->dws || client->slave) {
- if (chan->client_count)
- return -EBUSY;
- }
+ dev_vdbg(chan2dev(chan), "alloc_chan_resources\n");
/* ASSERT: channel is idle */
if (dma_readl(dw, CH_EN) & dwc->mask) {
- dev_dbg(&chan->dev, "DMA channel not idle?\n");
+ dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
return -EIO;
}
cfghi = DWC_CFGH_FIFO_MODE;
cfglo = 0;
- slave = client->slave;
- if (slave) {
+ dws = dwc->dws;
+ if (dws) {
/*
* We need controller-specific data to set up slave
* transfers.
*/
- BUG_ON(!slave->dma_dev || slave->dma_dev != dw->dma.dev);
-
- dws = container_of(slave, struct dw_dma_slave, slave);
+ BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev);
- dwc->dws = dws;
cfghi = dws->cfg_hi;
cfglo = dws->cfg_lo;
- } else {
- dwc->dws = NULL;
}
-
channel_writel(dwc, CFG_LO, cfglo);
channel_writel(dwc, CFG_HI, cfghi);
desc = kzalloc(sizeof(struct dw_desc), GFP_KERNEL);
if (!desc) {
- dev_info(&chan->dev,
+ dev_info(chan2dev(chan),
"only allocated %d descriptors\n", i);
spin_lock_bh(&dwc->lock);
break;
desc->txd.tx_submit = dwc_tx_submit;
desc->txd.flags = DMA_CTRL_ACK;
INIT_LIST_HEAD(&desc->txd.tx_list);
- desc->txd.phys = dma_map_single(chan->dev.parent, &desc->lli,
+ desc->txd.phys = dma_map_single(chan2parent(chan), &desc->lli,
sizeof(desc->lli), DMA_TO_DEVICE);
dwc_desc_put(dwc, desc);
spin_unlock_bh(&dwc->lock);
- dev_dbg(&chan->dev,
+ dev_dbg(chan2dev(chan),
"alloc_chan_resources allocated %d descriptors\n", i);
return i;
struct dw_desc *desc, *_desc;
LIST_HEAD(list);
- dev_dbg(&chan->dev, "free_chan_resources (descs allocated=%u)\n",
+ dev_dbg(chan2dev(chan), "free_chan_resources (descs allocated=%u)\n",
dwc->descs_allocated);
/* ASSERT: channel is idle */
spin_unlock_bh(&dwc->lock);
list_for_each_entry_safe(desc, _desc, &list, desc_node) {
- dev_vdbg(&chan->dev, " freeing descriptor %p\n", desc);
- dma_unmap_single(chan->dev.parent, desc->txd.phys,
+ dev_vdbg(chan2dev(chan), " freeing descriptor %p\n", desc);
+ dma_unmap_single(chan2parent(chan), desc->txd.phys,
sizeof(desc->lli), DMA_TO_DEVICE);
kfree(desc);
}
- dev_vdbg(&chan->dev, "free_chan_resources done\n");
+ dev_vdbg(chan2dev(chan), "free_chan_resources done\n");
}
/*----------------------------------------------------------------------*/
*
* Return - The number of descriptors allocated.
*/
-static int fsl_dma_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int fsl_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct fsl_dma_chan *fsl_chan = to_fsl_chan(chan);
*/
WARN_ON(fdev->feature != new_fsl_chan->feature);
- new_fsl_chan->dev = &new_fsl_chan->common.dev;
+ new_fsl_chan->dev = &new_fsl_chan->common.dev->device;
new_fsl_chan->reg_base = ioremap(new_fsl_chan->reg.start,
new_fsl_chan->reg.end - new_fsl_chan->reg.start + 1);
module_param(ioat_dca_enabled, int, 0644);
MODULE_PARM_DESC(ioat_dca_enabled, "control support of dca service (default: 1)");
-static int ioat_setup_functionality(struct pci_dev *pdev, void __iomem *iobase)
-{
- struct ioat_device *device = pci_get_drvdata(pdev);
- u8 version;
- int err = 0;
-
- version = readb(iobase + IOAT_VER_OFFSET);
- switch (version) {
- case IOAT_VER_1_2:
- device->dma = ioat_dma_probe(pdev, iobase);
- if (device->dma && ioat_dca_enabled)
- device->dca = ioat_dca_init(pdev, iobase);
- break;
- case IOAT_VER_2_0:
- device->dma = ioat_dma_probe(pdev, iobase);
- if (device->dma && ioat_dca_enabled)
- device->dca = ioat2_dca_init(pdev, iobase);
- break;
- case IOAT_VER_3_0:
- device->dma = ioat_dma_probe(pdev, iobase);
- if (device->dma && ioat_dca_enabled)
- device->dca = ioat3_dca_init(pdev, iobase);
- break;
- default:
- err = -ENODEV;
- break;
- }
- if (!device->dma)
- err = -ENODEV;
- return err;
-}
-
-static void ioat_shutdown_functionality(struct pci_dev *pdev)
-{
- struct ioat_device *device = pci_get_drvdata(pdev);
-
- dev_err(&pdev->dev, "Removing dma and dca services\n");
- if (device->dca) {
- unregister_dca_provider(device->dca);
- free_dca_provider(device->dca);
- device->dca = NULL;
- }
-
- if (device->dma) {
- ioat_dma_remove(device->dma);
- device->dma = NULL;
- }
-}
-
static struct pci_driver ioat_pci_driver = {
.name = "ioatdma",
.id_table = ioat_pci_tbl,
.probe = ioat_probe,
- .shutdown = ioat_shutdown_functionality,
.remove = __devexit_p(ioat_remove),
};
pci_set_master(pdev);
- err = ioat_setup_functionality(pdev, iobase);
+ switch (readb(iobase + IOAT_VER_OFFSET)) {
+ case IOAT_VER_1_2:
+ device->dma = ioat_dma_probe(pdev, iobase);
+ if (device->dma && ioat_dca_enabled)
+ device->dca = ioat_dca_init(pdev, iobase);
+ break;
+ case IOAT_VER_2_0:
+ device->dma = ioat_dma_probe(pdev, iobase);
+ if (device->dma && ioat_dca_enabled)
+ device->dca = ioat2_dca_init(pdev, iobase);
+ break;
+ case IOAT_VER_3_0:
+ device->dma = ioat_dma_probe(pdev, iobase);
+ if (device->dma && ioat_dca_enabled)
+ device->dca = ioat3_dca_init(pdev, iobase);
+ break;
+ default:
+ err = -ENODEV;
+ break;
+ }
+ if (!device->dma)
+ err = -ENODEV;
+
if (err)
goto err_version;
return err;
}
-/*
- * It is unsafe to remove this module: if removed while a requested
- * dma is outstanding, esp. from tcp, it is possible to hang while
- * waiting for something that will never finish. However, if you're
- * feeling lucky, this usually works just fine.
- */
static void __devexit ioat_remove(struct pci_dev *pdev)
{
struct ioat_device *device = pci_get_drvdata(pdev);
- ioat_shutdown_functionality(pdev);
+ dev_err(&pdev->dev, "Removing dma and dca services\n");
+ if (device->dca) {
+ unregister_dca_provider(device->dca);
+ free_dca_provider(device->dca);
+ device->dca = NULL;
+ }
+
+ if (device->dma) {
+ ioat_dma_remove(device->dma);
+ device->dma = NULL;
+ }
kfree(device);
}
* ioat_dma_alloc_chan_resources - returns the number of allocated descriptors
* @chan: the channel to be filled out
*/
-static int ioat_dma_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int ioat_dma_alloc_chan_resources(struct dma_chan *chan)
{
struct ioat_dma_chan *ioat_chan = to_ioat_chan(chan);
struct ioat_desc_sw *desc;
*/
#define IOAT_TEST_SIZE 2000
-DECLARE_COMPLETION(test_completion);
static void ioat_dma_test_callback(void *dma_async_param)
{
- printk(KERN_ERR "ioatdma: ioat_dma_test_callback(%p)\n",
- dma_async_param);
- complete(&test_completion);
+ struct completion *cmp = dma_async_param;
+
+ complete(cmp);
}
/**
dma_addr_t dma_dest, dma_src;
dma_cookie_t cookie;
int err = 0;
+ struct completion cmp;
src = kzalloc(sizeof(u8) * IOAT_TEST_SIZE, GFP_KERNEL);
if (!src)
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (device->common.device_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (device->common.device_alloc_chan_resources(dma_chan) < 1) {
dev_err(&device->pdev->dev,
"selftest cannot allocate chan resource\n");
err = -ENODEV;
}
async_tx_ack(tx);
+ init_completion(&cmp);
tx->callback = ioat_dma_test_callback;
- tx->callback_param = (void *)0x8086;
+ tx->callback_param = &cmp;
cookie = tx->tx_submit(tx);
if (cookie < 0) {
dev_err(&device->pdev->dev,
}
device->common.device_issue_pending(dma_chan);
- wait_for_completion_timeout(&test_completion, msecs_to_jiffies(3000));
+ wait_for_completion_timeout(&cmp, msecs_to_jiffies(3000));
if (device->common.device_is_tx_complete(dma_chan, cookie, NULL, NULL)
!= DMA_SUCCESS) {
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/async_tx.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/spinlock.h>
}
/* run dependent operations */
- async_tx_run_dependencies(&desc->async_tx);
+ dma_run_dependencies(&desc->async_tx);
return cookie;
}
break;
}
- BUG_ON(!seen_current);
-
if (cookie > 0) {
iop_chan->completed_cookie = cookie;
pr_debug("\tcompleted cookie %d\n", cookie);
* greater than 2x the number slots needed to satisfy a device->max_xor
* request.
* */
-static int iop_adma_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int iop_adma_alloc_chan_resources(struct dma_chan *chan)
{
char *hw_desc;
int idx;
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (iop_adma_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (iop_adma_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (iop_adma_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
struct iop_adma_device *device = platform_get_drvdata(dev);
struct dma_chan *chan, *_chan;
struct iop_adma_chan *iop_chan;
- int i;
struct iop_adma_platform_data *plat_data = dev->dev.platform_data;
dma_async_device_unregister(&device->common);
- for (i = 0; i < 3; i++) {
- unsigned int irq;
- irq = platform_get_irq(dev, i);
- free_irq(irq, device);
- }
-
dma_free_coherent(&dev->dev, plat_data->pool_size,
device->dma_desc_pool_virt, device->dma_desc_pool);
- do {
- struct resource *res;
- res = platform_get_resource(dev, IORESOURCE_MEM, 0);
- release_mem_region(res->start, res->end - res->start);
- } while (0);
-
list_for_each_entry_safe(chan, _chan, &device->common.channels,
device_node) {
iop_chan = to_iop_adma_chan(chan);
spin_lock_init(&iop_chan->lock);
INIT_LIST_HEAD(&iop_chan->chain);
INIT_LIST_HEAD(&iop_chan->all_slots);
- INIT_RCU_HEAD(&iop_chan->common.rcu);
iop_chan->common.device = dma_dev;
list_add_tail(&iop_chan->common.device_node, &dma_dev->channels);
return platform_driver_register(&iop_adma_driver);
}
-/* it's currently unsafe to unload this module */
-#if 0
static void __exit iop_adma_exit (void)
{
platform_driver_unregister(&iop_adma_driver);
return;
}
module_exit(iop_adma_exit);
-#endif
-
module_init(iop_adma_init);
MODULE_AUTHOR("Intel Corporation");
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/async_tx.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/spinlock.h>
}
/* run dependent operations */
- async_tx_run_dependencies(&desc->async_tx);
+ dma_run_dependencies(&desc->async_tx);
return cookie;
}
}
/* returns the number of allocated descriptors */
-static int mv_xor_alloc_chan_resources(struct dma_chan *chan,
- struct dma_client *client)
+static int mv_xor_alloc_chan_resources(struct dma_chan *chan)
{
char *hw_desc;
int idx;
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (mv_xor_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (mv_xor_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
dma_chan = container_of(device->common.channels.next,
struct dma_chan,
device_node);
- if (mv_xor_alloc_chan_resources(dma_chan, NULL) < 1) {
+ if (mv_xor_alloc_chan_resources(dma_chan) < 1) {
err = -ENODEV;
goto out;
}
INIT_LIST_HEAD(&mv_chan->chain);
INIT_LIST_HEAD(&mv_chan->completed_slots);
INIT_LIST_HEAD(&mv_chan->all_slots);
- INIT_RCU_HEAD(&mv_chan->common.rcu);
mv_chan->common.device = dma_dev;
list_add_tail(&mv_chan->common.device_node, &dma_dev->channels);
struct atmel_mci_dma {
#ifdef CONFIG_MMC_ATMELMCI_DMA
- struct dma_client client;
struct dma_chan *chan;
struct dma_async_tx_descriptor *data_desc;
#endif
/* If we don't have a channel, we can't do DMA */
chan = host->dma.chan;
- if (chan) {
- dma_chan_get(chan);
+ if (chan)
host->data_chan = chan;
- }
if (!chan)
return -ENODEV;
return IRQ_HANDLED;
}
-#ifdef CONFIG_MMC_ATMELMCI_DMA
-
-static inline struct atmel_mci *
-dma_client_to_atmel_mci(struct dma_client *client)
-{
- return container_of(client, struct atmel_mci, dma.client);
-}
-
-static enum dma_state_client atmci_dma_event(struct dma_client *client,
- struct dma_chan *chan, enum dma_state state)
-{
- struct atmel_mci *host;
- enum dma_state_client ret = DMA_NAK;
-
- host = dma_client_to_atmel_mci(client);
-
- switch (state) {
- case DMA_RESOURCE_AVAILABLE:
- spin_lock_bh(&host->lock);
- if (!host->dma.chan) {
- host->dma.chan = chan;
- ret = DMA_ACK;
- }
- spin_unlock_bh(&host->lock);
-
- if (ret == DMA_ACK)
- dev_info(&host->pdev->dev,
- "Using %s for DMA transfers\n",
- chan->dev.bus_id);
- break;
-
- case DMA_RESOURCE_REMOVED:
- spin_lock_bh(&host->lock);
- if (host->dma.chan == chan) {
- host->dma.chan = NULL;
- ret = DMA_ACK;
- }
- spin_unlock_bh(&host->lock);
-
- if (ret == DMA_ACK)
- dev_info(&host->pdev->dev,
- "Lost %s, falling back to PIO\n",
- chan->dev.bus_id);
- break;
-
- default:
- break;
- }
-
-
- return ret;
-}
-#endif /* CONFIG_MMC_ATMELMCI_DMA */
-
static int __init atmci_init_slot(struct atmel_mci *host,
struct mci_slot_pdata *slot_data, unsigned int id,
u32 sdc_reg)
mmc_free_host(slot->mmc);
}
+#ifdef CONFIG_MMC_ATMELMCI_DMA
+static bool filter(struct dma_chan *chan, void *slave)
+{
+ struct dw_dma_slave *dws = slave;
+
+ if (dws->dma_dev == chan->device->dev)
+ return true;
+ else
+ return false;
+}
+#endif
+
static int __init atmci_probe(struct platform_device *pdev)
{
struct mci_platform_data *pdata;
goto err_request_irq;
#ifdef CONFIG_MMC_ATMELMCI_DMA
- if (pdata->dma_slave) {
- struct dma_slave *slave = pdata->dma_slave;
+ if (pdata->dma_slave.dma_dev) {
+ struct dw_dma_slave *dws = &pdata->dma_slave;
+ dma_cap_mask_t mask;
- slave->tx_reg = regs->start + MCI_TDR;
- slave->rx_reg = regs->start + MCI_RDR;
+ dws->tx_reg = regs->start + MCI_TDR;
+ dws->rx_reg = regs->start + MCI_RDR;
/* Try to grab a DMA channel */
- host->dma.client.event_callback = atmci_dma_event;
- dma_cap_set(DMA_SLAVE, host->dma.client.cap_mask);
- host->dma.client.slave = slave;
-
- dma_async_client_register(&host->dma.client);
- dma_async_client_chan_request(&host->dma.client);
- } else {
- dev_notice(&pdev->dev, "DMA not available, using PIO\n");
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+ host->dma.chan = dma_request_channel(mask, filter, dws);
}
+ if (!host->dma.chan)
+ dev_notice(&pdev->dev, "DMA not available, using PIO\n");
#endif /* CONFIG_MMC_ATMELMCI_DMA */
platform_set_drvdata(pdev, host);
err_init_slot:
#ifdef CONFIG_MMC_ATMELMCI_DMA
- if (pdata->dma_slave)
- dma_async_client_unregister(&host->dma.client);
+ if (host->dma.chan)
+ dma_release_channel(host->dma.chan);
#endif
free_irq(irq, host);
err_request_irq:
clk_disable(host->mck);
#ifdef CONFIG_MMC_ATMELMCI_DMA
- if (host->dma.client.slave)
- dma_async_client_unregister(&host->dma.client);
+ if (host->dma.chan)
+ dma_release_channel(host->dma.chan);
#endif
free_irq(platform_get_irq(pdev, 0), host);
platform_driver_unregister(&atmci_driver);
}
-module_init(atmci_init);
+late_initcall(atmci_init); /* try to load after dma driver when built-in */
module_exit(atmci_exit);
MODULE_DESCRIPTION("Atmel Multimedia Card Interface driver");
};
#ifdef CONFIG_DMA_ENGINE
-void async_tx_issue_pending_all(void);
-enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
-void async_tx_run_dependencies(struct dma_async_tx_descriptor *tx);
+#define async_tx_issue_pending_all dma_issue_pending_all
#ifdef CONFIG_ARCH_HAS_ASYNC_TX_FIND_CHANNEL
#include <asm/async_tx.h>
#else
do { } while (0);
}
-static inline enum dma_status
-dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
-{
- return DMA_SUCCESS;
-}
-
-static inline void
-async_tx_run_dependencies(struct dma_async_tx_descriptor *tx,
- struct dma_chan *host_chan)
-{
- do { } while (0);
-}
-
static inline struct dma_chan *
async_tx_find_channel(struct dma_async_tx_descriptor *depend_tx,
enum dma_transaction_type tx_type, struct page **dst, int dst_count,
#define ATMEL_MCI_MAX_NR_SLOTS 2
-struct dma_slave;
+#include <linux/dw_dmac.h>
/**
* struct mci_slot_pdata - board-specific per-slot configuration
/**
* struct mci_platform_data - board-specific MMC/SDcard configuration
- * @dma_slave: DMA slave interface to use in data transfers, or NULL.
+ * @dma_slave: DMA slave interface to use in data transfers.
* @slot: Per-slot configuration data.
*/
struct mci_platform_data {
- struct dma_slave *dma_slave;
+ struct dw_dma_slave dma_slave;
struct mci_slot_pdata slot[ATMEL_MCI_MAX_NR_SLOTS];
};
#include <linux/dma-mapping.h>
/**
- * enum dma_state - resource PNP/power management state
- * @DMA_RESOURCE_SUSPEND: DMA device going into low power state
- * @DMA_RESOURCE_RESUME: DMA device returning to full power
- * @DMA_RESOURCE_AVAILABLE: DMA device available to the system
- * @DMA_RESOURCE_REMOVED: DMA device removed from the system
- */
-enum dma_state {
- DMA_RESOURCE_SUSPEND,
- DMA_RESOURCE_RESUME,
- DMA_RESOURCE_AVAILABLE,
- DMA_RESOURCE_REMOVED,
-};
-
-/**
- * enum dma_state_client - state of the channel in the client
- * @DMA_ACK: client would like to use, or was using this channel
- * @DMA_DUP: client has already seen this channel, or is not using this channel
- * @DMA_NAK: client does not want to see any more channels
- */
-enum dma_state_client {
- DMA_ACK,
- DMA_DUP,
- DMA_NAK,
-};
-
-/**
* typedef dma_cookie_t - an opaque DMA cookie
*
* if dma_cookie_t is >0 it's a DMA request cookie, <0 it's an error code
DMA_MEMSET,
DMA_MEMCPY_CRC32C,
DMA_INTERRUPT,
+ DMA_PRIVATE,
DMA_SLAVE,
};
/* last transaction type for creation of the capabilities mask */
#define DMA_TX_TYPE_END (DMA_SLAVE + 1)
-/**
- * enum dma_slave_width - DMA slave register access width.
- * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
- * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
- * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
- */
-enum dma_slave_width {
- DMA_SLAVE_WIDTH_8BIT,
- DMA_SLAVE_WIDTH_16BIT,
- DMA_SLAVE_WIDTH_32BIT,
-};
/**
* enum dma_ctrl_flags - DMA flags to augment operation preparation,
typedef struct { DECLARE_BITMAP(bits, DMA_TX_TYPE_END); } dma_cap_mask_t;
/**
- * struct dma_slave - Information about a DMA slave
- * @dev: device acting as DMA slave
- * @dma_dev: required DMA master device. If non-NULL, the client can not be
- * bound to other masters than this.
- * @tx_reg: physical address of data register used for
- * memory-to-peripheral transfers
- * @rx_reg: physical address of data register used for
- * peripheral-to-memory transfers
- * @reg_width: peripheral register width
- *
- * If dma_dev is non-NULL, the client can not be bound to other DMA
- * masters than the one corresponding to this device. The DMA master
- * driver may use this to determine if there is controller-specific
- * data wrapped around this struct. Drivers of platform code that sets
- * the dma_dev field must therefore make sure to use an appropriate
- * controller-specific dma slave structure wrapping this struct.
- */
-struct dma_slave {
- struct device *dev;
- struct device *dma_dev;
- dma_addr_t tx_reg;
- dma_addr_t rx_reg;
- enum dma_slave_width reg_width;
-};
-
-/**
* struct dma_chan_percpu - the per-CPU part of struct dma_chan
* @refcount: local_t used for open-coded "bigref" counting
* @memcpy_count: transaction counter
*/
struct dma_chan_percpu {
- local_t refcount;
/* stats */
unsigned long memcpy_count;
unsigned long bytes_transferred;
* @device: ptr to the dma device who supplies this channel, always !%NULL
* @cookie: last cookie value returned to client
* @chan_id: channel ID for sysfs
- * @class_dev: class device for sysfs
+ * @dev: class device for sysfs
* @refcount: kref, used in "bigref" slow-mode
* @slow_ref: indicates that the DMA channel is free
* @rcu: the DMA channel's RCU head
* @device_node: used to add this to the device chan list
* @local: per-cpu pointer to a struct dma_chan_percpu
* @client-count: how many clients are using this channel
+ * @table_count: number of appearances in the mem-to-mem allocation table
*/
struct dma_chan {
struct dma_device *device;
/* sysfs */
int chan_id;
- struct device dev;
-
- struct kref refcount;
- int slow_ref;
- struct rcu_head rcu;
+ struct dma_chan_dev *dev;
struct list_head device_node;
struct dma_chan_percpu *local;
int client_count;
+ int table_count;
};
-#define to_dma_chan(p) container_of(p, struct dma_chan, dev)
-
-void dma_chan_cleanup(struct kref *kref);
-
-static inline void dma_chan_get(struct dma_chan *chan)
-{
- if (unlikely(chan->slow_ref))
- kref_get(&chan->refcount);
- else {
- local_inc(&(per_cpu_ptr(chan->local, get_cpu())->refcount));
- put_cpu();
- }
-}
+/**
+ * struct dma_chan_dev - relate sysfs device node to backing channel device
+ * @chan - driver channel device
+ * @device - sysfs device
+ * @dev_id - parent dma_device dev_id
+ * @idr_ref - reference count to gate release of dma_device dev_id
+ */
+struct dma_chan_dev {
+ struct dma_chan *chan;
+ struct device device;
+ int dev_id;
+ atomic_t *idr_ref;
+};
-static inline void dma_chan_put(struct dma_chan *chan)
+static inline const char *dma_chan_name(struct dma_chan *chan)
{
- if (unlikely(chan->slow_ref))
- kref_put(&chan->refcount, dma_chan_cleanup);
- else {
- local_dec(&(per_cpu_ptr(chan->local, get_cpu())->refcount));
- put_cpu();
- }
+ return dev_name(&chan->dev->device);
}
-/*
- * typedef dma_event_callback - function pointer to a DMA event callback
- * For each channel added to the system this routine is called for each client.
- * If the client would like to use the channel it returns '1' to signal (ack)
- * the dmaengine core to take out a reference on the channel and its
- * corresponding device. A client must not 'ack' an available channel more
- * than once. When a channel is removed all clients are notified. If a client
- * is using the channel it must 'ack' the removal. A client must not 'ack' a
- * removed channel more than once.
- * @client - 'this' pointer for the client context
- * @chan - channel to be acted upon
- * @state - available or removed
- */
-struct dma_client;
-typedef enum dma_state_client (*dma_event_callback) (struct dma_client *client,
- struct dma_chan *chan, enum dma_state state);
+void dma_chan_cleanup(struct kref *kref);
/**
- * struct dma_client - info on the entity making use of DMA services
- * @event_callback: func ptr to call when something happens
- * @cap_mask: only return channels that satisfy the requested capabilities
- * a value of zero corresponds to any capability
- * @slave: data for preparing slave transfer. Must be non-NULL iff the
- * DMA_SLAVE capability is requested.
- * @global_node: list_head for global dma_client_list
+ * typedef dma_filter_fn - callback filter for dma_request_channel
+ * @chan: channel to be reviewed
+ * @filter_param: opaque parameter passed through dma_request_channel
+ *
+ * When this optional parameter is specified in a call to dma_request_channel a
+ * suitable channel is passed to this routine for further dispositioning before
+ * being returned. Where 'suitable' indicates a non-busy channel that
+ * satisfies the given capability mask. It returns 'true' to indicate that the
+ * channel is suitable.
*/
-struct dma_client {
- dma_event_callback event_callback;
- dma_cap_mask_t cap_mask;
- struct dma_slave *slave;
- struct list_head global_node;
-};
+typedef bool (*dma_filter_fn)(struct dma_chan *chan, void *filter_param);
typedef void (*dma_async_tx_callback)(void *dma_async_param);
/**
dma_cap_mask_t cap_mask;
int max_xor;
- struct kref refcount;
- struct completion done;
-
int dev_id;
struct device *dev;
- int (*device_alloc_chan_resources)(struct dma_chan *chan,
- struct dma_client *client);
+ int (*device_alloc_chan_resources)(struct dma_chan *chan);
void (*device_free_chan_resources)(struct dma_chan *chan);
struct dma_async_tx_descriptor *(*device_prep_dma_memcpy)(
/* --- public DMA engine API --- */
-void dma_async_client_register(struct dma_client *client);
-void dma_async_client_unregister(struct dma_client *client);
-void dma_async_client_chan_request(struct dma_client *client);
+void dmaengine_get(void);
+void dmaengine_put(void);
dma_cookie_t dma_async_memcpy_buf_to_buf(struct dma_chan *chan,
void *dest, void *src, size_t len);
dma_cookie_t dma_async_memcpy_buf_to_pg(struct dma_chan *chan,
set_bit(tx_type, dstp->bits);
}
+#define dma_cap_zero(mask) __dma_cap_zero(&(mask))
+static inline void __dma_cap_zero(dma_cap_mask_t *dstp)
+{
+ bitmap_zero(dstp->bits, DMA_TX_TYPE_END);
+}
+
#define dma_has_cap(tx, mask) __dma_has_cap((tx), &(mask))
static inline int
__dma_has_cap(enum dma_transaction_type tx_type, dma_cap_mask_t *srcp)
}
enum dma_status dma_sync_wait(struct dma_chan *chan, dma_cookie_t cookie);
+#ifdef CONFIG_DMA_ENGINE
+enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
+#else
+static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
+{
+ return DMA_SUCCESS;
+}
+#endif
/* --- DMA device --- */
int dma_async_device_register(struct dma_device *device);
void dma_async_device_unregister(struct dma_device *device);
+void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
+struct dma_chan *dma_find_channel(enum dma_transaction_type tx_type);
+void dma_issue_pending_all(void);
+#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
+struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, void *fn_param);
+void dma_release_channel(struct dma_chan *chan);
/* --- Helper iov-locking functions --- */
};
/**
+ * enum dw_dma_slave_width - DMA slave register access width.
+ * @DMA_SLAVE_WIDTH_8BIT: Do 8-bit slave register accesses
+ * @DMA_SLAVE_WIDTH_16BIT: Do 16-bit slave register accesses
+ * @DMA_SLAVE_WIDTH_32BIT: Do 32-bit slave register accesses
+ */
+enum dw_dma_slave_width {
+ DW_DMA_SLAVE_WIDTH_8BIT,
+ DW_DMA_SLAVE_WIDTH_16BIT,
+ DW_DMA_SLAVE_WIDTH_32BIT,
+};
+
+/**
* struct dw_dma_slave - Controller-specific information about a slave
- * @slave: Generic information about the slave
- * @ctl_lo: Platform-specific initializer for the CTL_LO register
+ *
+ * @dma_dev: required DMA master device
+ * @tx_reg: physical address of data register used for
+ * memory-to-peripheral transfers
+ * @rx_reg: physical address of data register used for
+ * peripheral-to-memory transfers
+ * @reg_width: peripheral register width
* @cfg_hi: Platform-specific initializer for the CFG_HI register
* @cfg_lo: Platform-specific initializer for the CFG_LO register
*/
struct dw_dma_slave {
- struct dma_slave slave;
+ struct device *dma_dev;
+ dma_addr_t tx_reg;
+ dma_addr_t rx_reg;
+ enum dw_dma_slave_width reg_width;
u32 cfg_hi;
u32 cfg_lo;
};
#define DWC_CFGL_HS_DST_POL (1 << 18) /* dst handshake active low */
#define DWC_CFGL_HS_SRC_POL (1 << 19) /* src handshake active low */
-static inline struct dw_dma_slave *to_dw_dma_slave(struct dma_slave *slave)
-{
- return container_of(slave, struct dw_dma_slave, slave);
-}
-
#endif /* DW_DMAC_H */
struct sk_buff *completion_queue;
struct napi_struct backlog;
-#ifdef CONFIG_NET_DMA
- struct dma_chan *net_dma;
-#endif
};
DECLARE_PER_CPU(struct softnet_data,softnet_data);
#include <linux/dmaengine.h>
#include <linux/skbuff.h>
-static inline struct dma_chan *get_softnet_dma(void)
-{
- struct dma_chan *chan;
- rcu_read_lock();
- chan = rcu_dereference(__get_cpu_var(softnet_data).net_dma);
- if (chan)
- dma_chan_get(chan);
- rcu_read_unlock();
- return chan;
-}
-
int dma_skb_copy_datagram_iovec(struct dma_chan* chan,
struct sk_buff *skb, int offset, struct iovec *to,
size_t len, struct dma_pinned_list *pinned_list);
static struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
static struct list_head ptype_all __read_mostly; /* Taps */
-#ifdef CONFIG_NET_DMA
-struct net_dma {
- struct dma_client client;
- spinlock_t lock;
- cpumask_t channel_mask;
- struct dma_chan **channels;
-};
-
-static enum dma_state_client
-netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
- enum dma_state state);
-
-static struct net_dma net_dma = {
- .client = {
- .event_callback = netdev_dma_event,
- },
-};
-#endif
-
/*
* The @dev_base_head list is protected by @dev_base_lock and the rtnl
* semaphore.
* There may not be any more sk_buffs coming right now, so push
* any pending DMA copies to hardware
*/
- if (!cpus_empty(net_dma.channel_mask)) {
- int chan_idx;
- for_each_cpu_mask_nr(chan_idx, net_dma.channel_mask) {
- struct dma_chan *chan = net_dma.channels[chan_idx];
- if (chan)
- dma_async_memcpy_issue_pending(chan);
- }
- }
+ dma_issue_pending_all();
#endif
return;
return NOTIFY_OK;
}
-#ifdef CONFIG_NET_DMA
-/**
- * net_dma_rebalance - try to maintain one DMA channel per CPU
- * @net_dma: DMA client and associated data (lock, channels, channel_mask)
- *
- * This is called when the number of channels allocated to the net_dma client
- * changes. The net_dma client tries to have one DMA channel per CPU.
- */
-
-static void net_dma_rebalance(struct net_dma *net_dma)
-{
- unsigned int cpu, i, n, chan_idx;
- struct dma_chan *chan;
-
- if (cpus_empty(net_dma->channel_mask)) {
- for_each_online_cpu(cpu)
- rcu_assign_pointer(per_cpu(softnet_data, cpu).net_dma, NULL);
- return;
- }
-
- i = 0;
- cpu = first_cpu(cpu_online_map);
-
- for_each_cpu_mask_nr(chan_idx, net_dma->channel_mask) {
- chan = net_dma->channels[chan_idx];
-
- n = ((num_online_cpus() / cpus_weight(net_dma->channel_mask))
- + (i < (num_online_cpus() %
- cpus_weight(net_dma->channel_mask)) ? 1 : 0));
-
- while(n) {
- per_cpu(softnet_data, cpu).net_dma = chan;
- cpu = next_cpu(cpu, cpu_online_map);
- n--;
- }
- i++;
- }
-}
-
-/**
- * netdev_dma_event - event callback for the net_dma_client
- * @client: should always be net_dma_client
- * @chan: DMA channel for the event
- * @state: DMA state to be handled
- */
-static enum dma_state_client
-netdev_dma_event(struct dma_client *client, struct dma_chan *chan,
- enum dma_state state)
-{
- int i, found = 0, pos = -1;
- struct net_dma *net_dma =
- container_of(client, struct net_dma, client);
- enum dma_state_client ack = DMA_DUP; /* default: take no action */
-
- spin_lock(&net_dma->lock);
- switch (state) {
- case DMA_RESOURCE_AVAILABLE:
- for (i = 0; i < nr_cpu_ids; i++)
- if (net_dma->channels[i] == chan) {
- found = 1;
- break;
- } else if (net_dma->channels[i] == NULL && pos < 0)
- pos = i;
-
- if (!found && pos >= 0) {
- ack = DMA_ACK;
- net_dma->channels[pos] = chan;
- cpu_set(pos, net_dma->channel_mask);
- net_dma_rebalance(net_dma);
- }
- break;
- case DMA_RESOURCE_REMOVED:
- for (i = 0; i < nr_cpu_ids; i++)
- if (net_dma->channels[i] == chan) {
- found = 1;
- pos = i;
- break;
- }
-
- if (found) {
- ack = DMA_ACK;
- cpu_clear(pos, net_dma->channel_mask);
- net_dma->channels[i] = NULL;
- net_dma_rebalance(net_dma);
- }
- break;
- default:
- break;
- }
- spin_unlock(&net_dma->lock);
-
- return ack;
-}
-
-/**
- * netdev_dma_register - register the networking subsystem as a DMA client
- */
-static int __init netdev_dma_register(void)
-{
- net_dma.channels = kzalloc(nr_cpu_ids * sizeof(struct net_dma),
- GFP_KERNEL);
- if (unlikely(!net_dma.channels)) {
- printk(KERN_NOTICE
- "netdev_dma: no memory for net_dma.channels\n");
- return -ENOMEM;
- }
- spin_lock_init(&net_dma.lock);
- dma_cap_set(DMA_MEMCPY, net_dma.client.cap_mask);
- dma_async_client_register(&net_dma.client);
- dma_async_client_chan_request(&net_dma.client);
- return 0;
-}
-
-#else
-static int __init netdev_dma_register(void) { return -ENODEV; }
-#endif /* CONFIG_NET_DMA */
/**
* netdev_increment_features - increment feature set by one
if (register_pernet_device(&default_device_ops))
goto out;
- netdev_dma_register();
-
open_softirq(NET_TX_SOFTIRQ, net_tx_action);
open_softirq(NET_RX_SOFTIRQ, net_rx_action);
hotcpu_notifier(dev_cpu_callback, 0);
dst_init();
dev_mcast_init();
+ #ifdef CONFIG_NET_DMA
+ dmaengine_get();
+ #endif
rc = 0;
out:
return rc;
if ((available < target) &&
(len > sysctl_tcp_dma_copybreak) && !(flags & MSG_PEEK) &&
!sysctl_tcp_low_latency &&
- __get_cpu_var(softnet_data).net_dma) {
+ dma_find_channel(DMA_MEMCPY)) {
preempt_enable_no_resched();
tp->ucopy.pinned_list =
dma_pin_iovec_pages(msg->msg_iov, len);
if (!(flags & MSG_TRUNC)) {
#ifdef CONFIG_NET_DMA
if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
- tp->ucopy.dma_chan = get_softnet_dma();
+ tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
if (tp->ucopy.dma_chan) {
tp->ucopy.dma_cookie = dma_skb_copy_datagram_iovec(
/* Safe to free early-copied skbs now */
__skb_queue_purge(&sk->sk_async_wait_queue);
- dma_chan_put(tp->ucopy.dma_chan);
tp->ucopy.dma_chan = NULL;
}
if (tp->ucopy.pinned_list) {
return 0;
if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
- tp->ucopy.dma_chan = get_softnet_dma();
+ tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
if (tp->ucopy.dma_chan && skb_csum_unnecessary(skb)) {
#ifdef CONFIG_NET_DMA
struct tcp_sock *tp = tcp_sk(sk);
if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
- tp->ucopy.dma_chan = get_softnet_dma();
+ tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
if (tp->ucopy.dma_chan)
ret = tcp_v4_do_rcv(sk, skb);
else
#ifdef CONFIG_NET_DMA
struct tcp_sock *tp = tcp_sk(sk);
if (!tp->ucopy.dma_chan && tp->ucopy.pinned_list)
- tp->ucopy.dma_chan = get_softnet_dma();
+ tp->ucopy.dma_chan = dma_find_channel(DMA_MEMCPY);
if (tp->ucopy.dma_chan)
ret = tcp_v6_do_rcv(sk, skb);
else
git://ftp.safe.ca / safe / jmp / linux-2.6 / commitdiff