libata-acpi: implement _GTM/_STM support

Implement _GTM/_STM support.  acpi_gtm is added to ata_port which
stores _GTM parameters over suspend/resume cycle.  A new hook
ata_acpi_on_suspend() is responsible for storing _GTM parameters
during suspend.  _STM is executed in ata_acpi_on_resume().  With this
change, invoking _GTF is safe on IDE hierarchy and acpi_sata check
before _GTF is removed.

ata_acpi_gtm() and ata_acpi_stm() implementation is taken from Alan
Cox's pata_acpi implementation.  ata_acpi_gtm() is fixed such that the
result parameter is not shifted by sizeof(union acpi_object).

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c
index 78db2e6..c059f78 100644 (file)
--- a/drivers/ata/libata-acpi.c
+++ b/drivers/ata/libata-acpi.c
@@ -101,6 +101,108 @@ void ata_acpi_associate(struct ata_host *host)
 }
 
 /**
+ * ata_acpi_gtm - execute _GTM
+ * @ap: target ATA port
+ * @gtm: out parameter for _GTM result
+ *
+ * Evaluate _GTM and store the result in @gtm.
+ *
+ * LOCKING:
+ * EH context.
+ *
+ * RETURNS:
+ * 0 on success, -ENOENT if _GTM doesn't exist, -errno on failure.
+ */
+static int ata_acpi_gtm(const struct ata_port *ap, struct ata_acpi_gtm *gtm)
+{
+       struct acpi_buffer output = { .length = ACPI_ALLOCATE_BUFFER };
+       union acpi_object *out_obj;
+       acpi_status status;
+       int rc = 0;
+
+       status = acpi_evaluate_object(ap->acpi_handle, "_GTM", NULL, &output);
+
+       rc = -ENOENT;
+       if (status == AE_NOT_FOUND)
+               goto out_free;
+
+       rc = -EINVAL;
+       if (ACPI_FAILURE(status)) {
+               ata_port_printk(ap, KERN_ERR,
+                               "ACPI get timing mode failed (AE 0x%x)\n",
+                               status);
+               goto out_free;
+       }
+
+       out_obj = output.pointer;
+       if (out_obj->type != ACPI_TYPE_BUFFER) {
+               ata_port_printk(ap, KERN_WARNING,
+                               "_GTM returned unexpected object type 0x%x\n",
+                               out_obj->type);
+
+               goto out_free;
+       }
+
+       if (out_obj->buffer.length != sizeof(struct ata_acpi_gtm)) {
+               ata_port_printk(ap, KERN_ERR,
+                               "_GTM returned invalid length %d\n",
+                               out_obj->buffer.length);
+               goto out_free;
+       }
+
+       memcpy(gtm, out_obj->buffer.pointer, sizeof(struct ata_acpi_gtm));
+       rc = 0;
+ out_free:
+       kfree(output.pointer);
+       return rc;
+}
+
+/**
+ * ata_acpi_stm - execute _STM
+ * @ap: target ATA port
+ * @stm: timing parameter to _STM
+ *
+ * Evaluate _STM with timing parameter @stm.
+ *
+ * LOCKING:
+ * EH context.
+ *
+ * RETURNS:
+ * 0 on success, -ENOENT if _STM doesn't exist, -errno on failure.
+ */
+static int ata_acpi_stm(const struct ata_port *ap, struct ata_acpi_gtm *stm)
+{
+       acpi_status status;
+       struct acpi_object_list         input;
+       union acpi_object               in_params[3];
+
+       in_params[0].type = ACPI_TYPE_BUFFER;
+       in_params[0].buffer.length = sizeof(struct ata_acpi_gtm);
+       in_params[0].buffer.pointer = (u8 *)stm;
+       /* Buffers for id may need byteswapping ? */
+       in_params[1].type = ACPI_TYPE_BUFFER;
+       in_params[1].buffer.length = 512;
+       in_params[1].buffer.pointer = (u8 *)ap->device[0].id;
+       in_params[2].type = ACPI_TYPE_BUFFER;
+       in_params[2].buffer.length = 512;
+       in_params[2].buffer.pointer = (u8 *)ap->device[1].id;
+
+       input.count = 3;
+       input.pointer = in_params;
+
+       status = acpi_evaluate_object(ap->acpi_handle, "_STM", &input, NULL);
+
+       if (status == AE_NOT_FOUND)
+               return -ENOENT;
+       if (ACPI_FAILURE(status)) {
+               ata_port_printk(ap, KERN_ERR,
+                       "ACPI set timing mode failed (status=0x%x)\n", status);
+               return -EINVAL;
+       }
+       return 0;
+}
+
+/**
  * ata_dev_get_GTF - get the drive bootup default taskfile settings
  * @dev: target ATA device
  * @gtf: output parameter for buffer containing _GTF taskfile arrays
@@ -355,6 +457,46 @@ static int ata_acpi_push_id(struct ata_device *dev)
 }
 
 /**
+ * ata_acpi_on_suspend - ATA ACPI hook called on suspend
+ * @ap: target ATA port
+ *
+ * This function is called when @ap is about to be suspended.  All
+ * devices are already put to sleep but the port_suspend() callback
+ * hasn't been executed yet.  Error return from this function aborts
+ * suspend.
+ *
+ * LOCKING:
+ * EH context.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+int ata_acpi_on_suspend(struct ata_port *ap)
+{
+       unsigned long flags;
+       int rc;
+
+       /* proceed iff per-port acpi_handle is valid */
+       if (!ap->acpi_handle)
+               return 0;
+       BUG_ON(ap->flags & ATA_FLAG_ACPI_SATA);
+
+       /* store timing parameters */
+       rc = ata_acpi_gtm(ap, &ap->acpi_gtm);
+
+       spin_lock_irqsave(ap->lock, flags);
+       if (rc == 0)
+               ap->pflags |= ATA_PFLAG_GTM_VALID;
+       else
+               ap->pflags &= ~ATA_PFLAG_GTM_VALID;
+       spin_unlock_irqrestore(ap->lock, flags);
+
+       if (rc == -ENOENT)
+               rc = 0;
+       return rc;
+}
+
+/**
  * ata_acpi_on_resume - ATA ACPI hook called on resume
  * @ap: target ATA port
  *
@@ -368,6 +510,13 @@ void ata_acpi_on_resume(struct ata_port *ap)
 {
        int i;
 
+       if (ap->acpi_handle && (ap->pflags & ATA_PFLAG_GTM_VALID)) {
+               BUG_ON(ap->flags & ATA_FLAG_ACPI_SATA);
+
+               /* restore timing parameters */
+               ata_acpi_stm(ap, &ap->acpi_gtm);
+       }
+
        /* schedule _GTF */
        for (i = 0; i < ATA_MAX_DEVICES; i++)
                ap->device[i].flags |= ATA_DFLAG_ACPI_PENDING;
@@ -394,10 +543,6 @@ int ata_acpi_on_devcfg(struct ata_device *dev)
        int acpi_sata = ap->flags & ATA_FLAG_ACPI_SATA;
        int rc;
 
-       /* XXX: _STM isn't implemented yet, skip if IDE for now */
-       if (!acpi_sata)
-               return 0;
-
        if (!dev->acpi_handle)
                return 0;
 

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index fed217d..9ee0a8c 100644 (file)
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -2154,19 +2154,25 @@ static void ata_eh_handle_port_suspend(struct ata_port *ap)
 
        WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
 
+       /* tell ACPI we're suspending */
+       rc = ata_acpi_on_suspend(ap);
+       if (rc)
+               goto out;
+
        /* suspend */
        ata_eh_freeze_port(ap);
 
        if (ap->ops->port_suspend)
                rc = ap->ops->port_suspend(ap, ap->pm_mesg);
 
+ out:
        /* report result */
        spin_lock_irqsave(ap->lock, flags);
 
        ap->pflags &= ~ATA_PFLAG_PM_PENDING;
        if (rc == 0)
                ap->pflags |= ATA_PFLAG_SUSPENDED;
-       else
+       else if (ap->pflags & ATA_PFLAG_FROZEN)
                ata_port_schedule_eh(ap);
 
        if (ap->pm_result) {

diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index bee7cbc..ba17fc5 100644 (file)
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -99,10 +99,12 @@ extern struct ata_port *ata_port_alloc(struct ata_host *host);
 /* libata-acpi.c */
 #ifdef CONFIG_ATA_ACPI
 extern void ata_acpi_associate(struct ata_host *host);
+extern int ata_acpi_on_suspend(struct ata_port *ap);
 extern void ata_acpi_on_resume(struct ata_port *ap);
 extern int ata_acpi_on_devcfg(struct ata_device *adev);
 #else
 static inline void ata_acpi_associate(struct ata_host *host) { }
+static inline int ata_acpi_on_suspend(struct ata_port *ap) { return 0; }
 static inline void ata_acpi_on_resume(struct ata_port *ap) { }
 static inline int ata_acpi_on_devcfg(struct ata_device *adev) { return 0; }
 #endif

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 0c4f63b..8d3e391 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -198,6 +198,7 @@ enum {
        ATA_PFLAG_FLUSH_PORT_TASK = (1 << 16), /* flush port task */
        ATA_PFLAG_SUSPENDED     = (1 << 17), /* port is suspended (power) */
        ATA_PFLAG_PM_PENDING    = (1 << 18), /* PM operation pending */
+       ATA_PFLAG_GTM_VALID     = (1 << 19), /* acpi_gtm data valid */
 
        /* struct ata_queued_cmd flags */
        ATA_QCFLAG_ACTIVE       = (1 << 0), /* cmd not yet ack'd to scsi lyer */
@@ -493,6 +494,17 @@ struct ata_eh_context {
        unsigned int            did_probe_mask;
 };
 
+struct ata_acpi_drive
+{
+       u32 pio;
+       u32 dma;
+} __packed;
+
+struct ata_acpi_gtm {
+       struct ata_acpi_drive drive[2];
+       u32 flags;
+} __packed;
+
 struct ata_port {
        struct Scsi_Host        *scsi_host; /* our co-allocated scsi host */
        const struct ata_port_operations *ops;
@@ -555,6 +567,7 @@ struct ata_port {
 
 #ifdef CONFIG_ATA_ACPI
        acpi_handle             acpi_handle;
+       struct ata_acpi_gtm     acpi_gtm;
 #endif
        u8                      sector_buf[ATA_SECT_SIZE]; /* owned by EH */
 };