#include <linux/clocksource.h>
#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/sysdev.h>
#include <linux/delay.h>
#include <linux/errno.h>
+#include <linux/slab.h>
#include <linux/hpet.h>
#include <linux/init.h>
-#include <linux/sysdev.h>
+#include <linux/cpu.h>
#include <linux/pm.h>
+#include <linux/io.h>
#include <asm/fixmap.h>
-#include <asm/hpet.h>
#include <asm/i8253.h>
-#include <asm/io.h>
+#include <asm/hpet.h>
-#define HPET_MASK CLOCKSOURCE_MASK(32)
-#define HPET_SHIFT 22
+#define HPET_MASK CLOCKSOURCE_MASK(32)
+#define HPET_SHIFT 22
/* FSEC = 10^-15
NSEC = 10^-9 */
-#define FSEC_PER_NSEC 1000000
+#define FSEC_PER_NSEC 1000000L
+
+#define HPET_DEV_USED_BIT 2
+#define HPET_DEV_USED (1 << HPET_DEV_USED_BIT)
+#define HPET_DEV_VALID 0x8
+#define HPET_DEV_FSB_CAP 0x1000
+#define HPET_DEV_PERI_CAP 0x2000
+
+#define EVT_TO_HPET_DEV(evt) container_of(evt, struct hpet_dev, evt)
/*
* HPET address is set in acpi/boot.c, when an ACPI entry exists
*/
-unsigned long hpet_address;
-static void __iomem *hpet_virt_address;
+unsigned long hpet_address;
+u8 hpet_blockid; /* OS timer block num */
+u8 hpet_msi_disable;
+
+#ifdef CONFIG_PCI_MSI
+static unsigned long hpet_num_timers;
+#endif
+static void __iomem *hpet_virt_address;
+
+struct hpet_dev {
+ struct clock_event_device evt;
+ unsigned int num;
+ int cpu;
+ unsigned int irq;
+ unsigned int flags;
+ char name[10];
+};
-unsigned long hpet_readl(unsigned long a)
+inline unsigned int hpet_readl(unsigned int a)
{
return readl(hpet_virt_address + a);
}
-static inline void hpet_writel(unsigned long d, unsigned long a)
+static inline void hpet_writel(unsigned int d, unsigned int a)
{
writel(d, hpet_virt_address + a);
}
#ifdef CONFIG_X86_64
-
#include <asm/pgtable.h>
-
-static inline void hpet_set_mapping(void)
-{
- set_fixmap_nocache(FIX_HPET_BASE, hpet_address);
- __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);
- hpet_virt_address = (void __iomem *)fix_to_virt(FIX_HPET_BASE);
-}
-
-static inline void hpet_clear_mapping(void)
-{
- hpet_virt_address = NULL;
-}
-
-#else
+#endif
static inline void hpet_set_mapping(void)
{
hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
+#ifdef CONFIG_X86_64
+ __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);
+#endif
}
static inline void hpet_clear_mapping(void)
iounmap(hpet_virt_address);
hpet_virt_address = NULL;
}
-#endif
/*
* HPET command line enable / disable
*/
static int boot_hpet_disable;
int hpet_force_user;
+static int hpet_verbose;
-static int __init hpet_setup(char* str)
+static int __init hpet_setup(char *str)
{
if (str) {
if (!strncmp("disable", str, 7))
boot_hpet_disable = 1;
if (!strncmp("force", str, 5))
hpet_force_user = 1;
+ if (!strncmp("verbose", str, 7))
+ hpet_verbose = 1;
}
return 1;
}
static inline int is_hpet_capable(void)
{
- return (!boot_hpet_disable && hpet_address);
+ return !boot_hpet_disable && hpet_address;
}
/*
}
EXPORT_SYMBOL_GPL(is_hpet_enabled);
+static void _hpet_print_config(const char *function, int line)
+{
+ u32 i, timers, l, h;
+ printk(KERN_INFO "hpet: %s(%d):\n", function, line);
+ l = hpet_readl(HPET_ID);
+ h = hpet_readl(HPET_PERIOD);
+ timers = ((l & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1;
+ printk(KERN_INFO "hpet: ID: 0x%x, PERIOD: 0x%x\n", l, h);
+ l = hpet_readl(HPET_CFG);
+ h = hpet_readl(HPET_STATUS);
+ printk(KERN_INFO "hpet: CFG: 0x%x, STATUS: 0x%x\n", l, h);
+ l = hpet_readl(HPET_COUNTER);
+ h = hpet_readl(HPET_COUNTER+4);
+ printk(KERN_INFO "hpet: COUNTER_l: 0x%x, COUNTER_h: 0x%x\n", l, h);
+
+ for (i = 0; i < timers; i++) {
+ l = hpet_readl(HPET_Tn_CFG(i));
+ h = hpet_readl(HPET_Tn_CFG(i)+4);
+ printk(KERN_INFO "hpet: T%d: CFG_l: 0x%x, CFG_h: 0x%x\n",
+ i, l, h);
+ l = hpet_readl(HPET_Tn_CMP(i));
+ h = hpet_readl(HPET_Tn_CMP(i)+4);
+ printk(KERN_INFO "hpet: T%d: CMP_l: 0x%x, CMP_h: 0x%x\n",
+ i, l, h);
+ l = hpet_readl(HPET_Tn_ROUTE(i));
+ h = hpet_readl(HPET_Tn_ROUTE(i)+4);
+ printk(KERN_INFO "hpet: T%d ROUTE_l: 0x%x, ROUTE_h: 0x%x\n",
+ i, l, h);
+ }
+}
+
+#define hpet_print_config() \
+do { \
+ if (hpet_verbose) \
+ _hpet_print_config(__FUNCTION__, __LINE__); \
+} while (0)
+
/*
* When the hpet driver (/dev/hpet) is enabled, we need to reserve
* timer 0 and timer 1 in case of RTC emulation.
*/
#ifdef CONFIG_HPET
-static void hpet_reserve_platform_timers(unsigned long id)
+
+static void hpet_reserve_msi_timers(struct hpet_data *hd);
+
+static void hpet_reserve_platform_timers(unsigned int id)
{
struct hpet __iomem *hpet = hpet_virt_address;
struct hpet_timer __iomem *timer = &hpet->hpet_timers[2];
nrtimers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1;
- memset(&hd, 0, sizeof (hd));
- hd.hd_phys_address = hpet_address;
- hd.hd_address = hpet;
- hd.hd_nirqs = nrtimers;
- hd.hd_flags = HPET_DATA_PLATFORM;
+ memset(&hd, 0, sizeof(hd));
+ hd.hd_phys_address = hpet_address;
+ hd.hd_address = hpet;
+ hd.hd_nirqs = nrtimers;
hpet_reserve_timer(&hd, 0);
#ifdef CONFIG_HPET_EMULATE_RTC
hpet_reserve_timer(&hd, 1);
#endif
+ /*
+ * NOTE that hd_irq[] reflects IOAPIC input pins (LEGACY_8254
+ * is wrong for i8259!) not the output IRQ. Many BIOS writers
+ * don't bother configuring *any* comparator interrupts.
+ */
hd.hd_irq[0] = HPET_LEGACY_8254;
hd.hd_irq[1] = HPET_LEGACY_RTC;
- for (i = 2; i < nrtimers; timer++, i++)
- hd.hd_irq[i] = (timer->hpet_config & Tn_INT_ROUTE_CNF_MASK) >>
- Tn_INT_ROUTE_CNF_SHIFT;
+ for (i = 2; i < nrtimers; timer++, i++) {
+ hd.hd_irq[i] = (readl(&timer->hpet_config) &
+ Tn_INT_ROUTE_CNF_MASK) >> Tn_INT_ROUTE_CNF_SHIFT;
+ }
+
+ hpet_reserve_msi_timers(&hd);
hpet_alloc(&hd);
}
#else
-static void hpet_reserve_platform_timers(unsigned long id) { }
+static void hpet_reserve_platform_timers(unsigned int id) { }
#endif
/*
.rating = 50,
};
-static void hpet_start_counter(void)
+static void hpet_stop_counter(void)
{
unsigned long cfg = hpet_readl(HPET_CFG);
-
cfg &= ~HPET_CFG_ENABLE;
hpet_writel(cfg, HPET_CFG);
+}
+
+static void hpet_reset_counter(void)
+{
hpet_writel(0, HPET_COUNTER);
hpet_writel(0, HPET_COUNTER + 4);
+}
+
+static void hpet_start_counter(void)
+{
+ unsigned int cfg = hpet_readl(HPET_CFG);
cfg |= HPET_CFG_ENABLE;
hpet_writel(cfg, HPET_CFG);
}
+static void hpet_restart_counter(void)
+{
+ hpet_stop_counter();
+ hpet_reset_counter();
+ hpet_start_counter();
+}
+
static void hpet_resume_device(void)
{
force_hpet_resume();
}
-static void hpet_restart_counter(void)
+static void hpet_resume_counter(struct clocksource *cs)
{
hpet_resume_device();
- hpet_start_counter();
+ hpet_restart_counter();
}
static void hpet_enable_legacy_int(void)
{
- unsigned long cfg = hpet_readl(HPET_CFG);
+ unsigned int cfg = hpet_readl(HPET_CFG);
cfg |= HPET_CFG_LEGACY;
hpet_writel(cfg, HPET_CFG);
static void hpet_legacy_clockevent_register(void)
{
- uint64_t hpet_freq;
-
/* Start HPET legacy interrupts */
hpet_enable_legacy_int();
/*
- * The period is a femto seconds value. We need to calculate the
- * scaled math multiplication factor for nanosecond to hpet tick
- * conversion.
+ * The mult factor is defined as (include/linux/clockchips.h)
+ * mult/2^shift = cyc/ns (in contrast to ns/cyc in clocksource.h)
+ * hpet_period is in units of femtoseconds (per cycle), so
+ * mult/2^shift = cyc/ns = 10^6/hpet_period
+ * mult = (10^6 * 2^shift)/hpet_period
+ * mult = (FSEC_PER_NSEC << hpet_clockevent.shift)/hpet_period
*/
- hpet_freq = 1000000000000000ULL;
- do_div(hpet_freq, hpet_period);
- hpet_clockevent.mult = div_sc((unsigned long) hpet_freq,
- NSEC_PER_SEC, 32);
+ hpet_clockevent.mult = div_sc((unsigned long) FSEC_PER_NSEC,
+ hpet_period, hpet_clockevent.shift);
/* Calculate the min / max delta */
hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF,
&hpet_clockevent);
- hpet_clockevent.min_delta_ns = clockevent_delta2ns(0x30,
- &hpet_clockevent);
+ /* 5 usec minimum reprogramming delta. */
+ hpet_clockevent.min_delta_ns = 5000;
/*
* Start hpet with the boot cpu mask and make it
* global after the IO_APIC has been initialized.
*/
- hpet_clockevent.cpumask = cpumask_of_cpu(smp_processor_id());
+ hpet_clockevent.cpumask = cpumask_of(smp_processor_id());
clockevents_register_device(&hpet_clockevent);
global_clock_event = &hpet_clockevent;
printk(KERN_DEBUG "hpet clockevent registered\n");
}
-static void hpet_legacy_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
+static int hpet_setup_msi_irq(unsigned int irq);
+
+static void hpet_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt, int timer)
{
- unsigned long cfg, cmp, now;
+ unsigned int cfg, cmp, now;
uint64_t delta;
- switch(mode) {
+ switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
- delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * hpet_clockevent.mult;
- delta >>= hpet_clockevent.shift;
+ hpet_stop_counter();
+ delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * evt->mult;
+ delta >>= evt->shift;
now = hpet_readl(HPET_COUNTER);
- cmp = now + (unsigned long) delta;
- cfg = hpet_readl(HPET_T0_CFG);
+ cmp = now + (unsigned int) delta;
+ cfg = hpet_readl(HPET_Tn_CFG(timer));
+ /* Make sure we use edge triggered interrupts */
+ cfg &= ~HPET_TN_LEVEL;
cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC |
HPET_TN_SETVAL | HPET_TN_32BIT;
- hpet_writel(cfg, HPET_T0_CFG);
+ hpet_writel(cfg, HPET_Tn_CFG(timer));
+ hpet_writel(cmp, HPET_Tn_CMP(timer));
+ udelay(1);
/*
- * The first write after writing TN_SETVAL to the
- * config register sets the counter value, the second
- * write sets the period.
+ * HPET on AMD 81xx needs a second write (with HPET_TN_SETVAL
+ * cleared) to T0_CMP to set the period. The HPET_TN_SETVAL
+ * bit is automatically cleared after the first write.
+ * (See AMD-8111 HyperTransport I/O Hub Data Sheet,
+ * Publication # 24674)
*/
- hpet_writel(cmp, HPET_T0_CMP);
- udelay(1);
- hpet_writel((unsigned long) delta, HPET_T0_CMP);
+ hpet_writel((unsigned int) delta, HPET_Tn_CMP(timer));
+ hpet_start_counter();
+ hpet_print_config();
break;
case CLOCK_EVT_MODE_ONESHOT:
- cfg = hpet_readl(HPET_T0_CFG);
+ cfg = hpet_readl(HPET_Tn_CFG(timer));
cfg &= ~HPET_TN_PERIODIC;
cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
- hpet_writel(cfg, HPET_T0_CFG);
+ hpet_writel(cfg, HPET_Tn_CFG(timer));
break;
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
- cfg = hpet_readl(HPET_T0_CFG);
+ cfg = hpet_readl(HPET_Tn_CFG(timer));
cfg &= ~HPET_TN_ENABLE;
- hpet_writel(cfg, HPET_T0_CFG);
+ hpet_writel(cfg, HPET_Tn_CFG(timer));
break;
case CLOCK_EVT_MODE_RESUME:
- hpet_enable_legacy_int();
+ if (timer == 0) {
+ hpet_enable_legacy_int();
+ } else {
+ struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
+ hpet_setup_msi_irq(hdev->irq);
+ disable_irq(hdev->irq);
+ irq_set_affinity(hdev->irq, cpumask_of(hdev->cpu));
+ enable_irq(hdev->irq);
+ }
+ hpet_print_config();
break;
}
}
-static int hpet_legacy_next_event(unsigned long delta,
- struct clock_event_device *evt)
+static int hpet_next_event(unsigned long delta,
+ struct clock_event_device *evt, int timer)
{
- unsigned long cnt;
+ u32 cnt;
cnt = hpet_readl(HPET_COUNTER);
- cnt += delta;
- hpet_writel(cnt, HPET_T0_CMP);
+ cnt += (u32) delta;
+ hpet_writel(cnt, HPET_Tn_CMP(timer));
+
+ /*
+ * We need to read back the CMP register on certain HPET
+ * implementations (ATI chipsets) which seem to delay the
+ * transfer of the compare register into the internal compare
+ * logic. With small deltas this might actually be too late as
+ * the counter could already be higher than the compare value
+ * at that point and we would wait for the next hpet interrupt
+ * forever. We found out that reading the CMP register back
+ * forces the transfer so we can rely on the comparison with
+ * the counter register below. If the read back from the
+ * compare register does not match the value we programmed
+ * then we might have a real hardware problem. We can not do
+ * much about it here, but at least alert the user/admin with
+ * a prominent warning.
+ */
+ WARN_ONCE(hpet_readl(HPET_Tn_CMP(timer)) != cnt,
+ KERN_WARNING "hpet: compare register read back failed.\n");
+
+ return (s32)(hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0;
+}
+
+static void hpet_legacy_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ hpet_set_mode(mode, evt, 0);
+}
+
+static int hpet_legacy_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ return hpet_next_event(delta, evt, 0);
+}
+
+/*
+ * HPET MSI Support
+ */
+#ifdef CONFIG_PCI_MSI
+
+static DEFINE_PER_CPU(struct hpet_dev *, cpu_hpet_dev);
+static struct hpet_dev *hpet_devs;
+
+void hpet_msi_unmask(unsigned int irq)
+{
+ struct hpet_dev *hdev = get_irq_data(irq);
+ unsigned int cfg;
+
+ /* unmask it */
+ cfg = hpet_readl(HPET_Tn_CFG(hdev->num));
+ cfg |= HPET_TN_FSB;
+ hpet_writel(cfg, HPET_Tn_CFG(hdev->num));
+}
+
+void hpet_msi_mask(unsigned int irq)
+{
+ unsigned int cfg;
+ struct hpet_dev *hdev = get_irq_data(irq);
+
+ /* mask it */
+ cfg = hpet_readl(HPET_Tn_CFG(hdev->num));
+ cfg &= ~HPET_TN_FSB;
+ hpet_writel(cfg, HPET_Tn_CFG(hdev->num));
+}
+
+void hpet_msi_write(unsigned int irq, struct msi_msg *msg)
+{
+ struct hpet_dev *hdev = get_irq_data(irq);
+
+ hpet_writel(msg->data, HPET_Tn_ROUTE(hdev->num));
+ hpet_writel(msg->address_lo, HPET_Tn_ROUTE(hdev->num) + 4);
+}
+
+void hpet_msi_read(unsigned int irq, struct msi_msg *msg)
+{
+ struct hpet_dev *hdev = get_irq_data(irq);
+
+ msg->data = hpet_readl(HPET_Tn_ROUTE(hdev->num));
+ msg->address_lo = hpet_readl(HPET_Tn_ROUTE(hdev->num) + 4);
+ msg->address_hi = 0;
+}
+
+static void hpet_msi_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
+ hpet_set_mode(mode, evt, hdev->num);
+}
+
+static int hpet_msi_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
+ return hpet_next_event(delta, evt, hdev->num);
+}
+
+static int hpet_setup_msi_irq(unsigned int irq)
+{
+ if (arch_setup_hpet_msi(irq, hpet_blockid)) {
+ destroy_irq(irq);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int hpet_assign_irq(struct hpet_dev *dev)
+{
+ unsigned int irq;
+
+ irq = create_irq();
+ if (!irq)
+ return -EINVAL;
+
+ set_irq_data(irq, dev);
+
+ if (hpet_setup_msi_irq(irq))
+ return -EINVAL;
+
+ dev->irq = irq;
+ return 0;
+}
+
+static irqreturn_t hpet_interrupt_handler(int irq, void *data)
+{
+ struct hpet_dev *dev = (struct hpet_dev *)data;
+ struct clock_event_device *hevt = &dev->evt;
+
+ if (!hevt->event_handler) {
+ printk(KERN_INFO "Spurious HPET timer interrupt on HPET timer %d\n",
+ dev->num);
+ return IRQ_HANDLED;
+ }
+
+ hevt->event_handler(hevt);
+ return IRQ_HANDLED;
+}
+
+static int hpet_setup_irq(struct hpet_dev *dev)
+{
+
+ if (request_irq(dev->irq, hpet_interrupt_handler,
+ IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING,
+ dev->name, dev))
+ return -1;
+
+ disable_irq(dev->irq);
+ irq_set_affinity(dev->irq, cpumask_of(dev->cpu));
+ enable_irq(dev->irq);
+
+ printk(KERN_DEBUG "hpet: %s irq %d for MSI\n",
+ dev->name, dev->irq);
+
+ return 0;
+}
+
+/* This should be called in specific @cpu */
+static void init_one_hpet_msi_clockevent(struct hpet_dev *hdev, int cpu)
+{
+ struct clock_event_device *evt = &hdev->evt;
+ uint64_t hpet_freq;
+
+ WARN_ON(cpu != smp_processor_id());
+ if (!(hdev->flags & HPET_DEV_VALID))
+ return;
+
+ if (hpet_setup_msi_irq(hdev->irq))
+ return;
+
+ hdev->cpu = cpu;
+ per_cpu(cpu_hpet_dev, cpu) = hdev;
+ evt->name = hdev->name;
+ hpet_setup_irq(hdev);
+ evt->irq = hdev->irq;
+
+ evt->rating = 110;
+ evt->features = CLOCK_EVT_FEAT_ONESHOT;
+ if (hdev->flags & HPET_DEV_PERI_CAP)
+ evt->features |= CLOCK_EVT_FEAT_PERIODIC;
+
+ evt->set_mode = hpet_msi_set_mode;
+ evt->set_next_event = hpet_msi_next_event;
+ evt->shift = 32;
+
+ /*
+ * The period is a femto seconds value. We need to calculate the
+ * scaled math multiplication factor for nanosecond to hpet tick
+ * conversion.
+ */
+ hpet_freq = 1000000000000000ULL;
+ do_div(hpet_freq, hpet_period);
+ evt->mult = div_sc((unsigned long) hpet_freq,
+ NSEC_PER_SEC, evt->shift);
+ /* Calculate the max delta */
+ evt->max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, evt);
+ /* 5 usec minimum reprogramming delta. */
+ evt->min_delta_ns = 5000;
+
+ evt->cpumask = cpumask_of(hdev->cpu);
+ clockevents_register_device(evt);
+}
+
+#ifdef CONFIG_HPET
+/* Reserve at least one timer for userspace (/dev/hpet) */
+#define RESERVE_TIMERS 1
+#else
+#define RESERVE_TIMERS 0
+#endif
- return ((long)(hpet_readl(HPET_COUNTER) - cnt ) > 0) ? -ETIME : 0;
+static void hpet_msi_capability_lookup(unsigned int start_timer)
+{
+ unsigned int id;
+ unsigned int num_timers;
+ unsigned int num_timers_used = 0;
+ int i;
+
+ if (hpet_msi_disable)
+ return;
+
+ if (boot_cpu_has(X86_FEATURE_ARAT))
+ return;
+ id = hpet_readl(HPET_ID);
+
+ num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT);
+ num_timers++; /* Value read out starts from 0 */
+ hpet_print_config();
+
+ hpet_devs = kzalloc(sizeof(struct hpet_dev) * num_timers, GFP_KERNEL);
+ if (!hpet_devs)
+ return;
+
+ hpet_num_timers = num_timers;
+
+ for (i = start_timer; i < num_timers - RESERVE_TIMERS; i++) {
+ struct hpet_dev *hdev = &hpet_devs[num_timers_used];
+ unsigned int cfg = hpet_readl(HPET_Tn_CFG(i));
+
+ /* Only consider HPET timer with MSI support */
+ if (!(cfg & HPET_TN_FSB_CAP))
+ continue;
+
+ hdev->flags = 0;
+ if (cfg & HPET_TN_PERIODIC_CAP)
+ hdev->flags |= HPET_DEV_PERI_CAP;
+ hdev->num = i;
+
+ sprintf(hdev->name, "hpet%d", i);
+ if (hpet_assign_irq(hdev))
+ continue;
+
+ hdev->flags |= HPET_DEV_FSB_CAP;
+ hdev->flags |= HPET_DEV_VALID;
+ num_timers_used++;
+ if (num_timers_used == num_possible_cpus())
+ break;
+ }
+
+ printk(KERN_INFO "HPET: %d timers in total, %d timers will be used for per-cpu timer\n",
+ num_timers, num_timers_used);
+}
+
+#ifdef CONFIG_HPET
+static void hpet_reserve_msi_timers(struct hpet_data *hd)
+{
+ int i;
+
+ if (!hpet_devs)
+ return;
+
+ for (i = 0; i < hpet_num_timers; i++) {
+ struct hpet_dev *hdev = &hpet_devs[i];
+
+ if (!(hdev->flags & HPET_DEV_VALID))
+ continue;
+
+ hd->hd_irq[hdev->num] = hdev->irq;
+ hpet_reserve_timer(hd, hdev->num);
+ }
}
+#endif
+
+static struct hpet_dev *hpet_get_unused_timer(void)
+{
+ int i;
+
+ if (!hpet_devs)
+ return NULL;
+
+ for (i = 0; i < hpet_num_timers; i++) {
+ struct hpet_dev *hdev = &hpet_devs[i];
+
+ if (!(hdev->flags & HPET_DEV_VALID))
+ continue;
+ if (test_and_set_bit(HPET_DEV_USED_BIT,
+ (unsigned long *)&hdev->flags))
+ continue;
+ return hdev;
+ }
+ return NULL;
+}
+
+struct hpet_work_struct {
+ struct delayed_work work;
+ struct completion complete;
+};
+
+static void hpet_work(struct work_struct *w)
+{
+ struct hpet_dev *hdev;
+ int cpu = smp_processor_id();
+ struct hpet_work_struct *hpet_work;
+
+ hpet_work = container_of(w, struct hpet_work_struct, work.work);
+
+ hdev = hpet_get_unused_timer();
+ if (hdev)
+ init_one_hpet_msi_clockevent(hdev, cpu);
+
+ complete(&hpet_work->complete);
+}
+
+static int hpet_cpuhp_notify(struct notifier_block *n,
+ unsigned long action, void *hcpu)
+{
+ unsigned long cpu = (unsigned long)hcpu;
+ struct hpet_work_struct work;
+ struct hpet_dev *hdev = per_cpu(cpu_hpet_dev, cpu);
+
+ switch (action & 0xf) {
+ case CPU_ONLINE:
+ INIT_DELAYED_WORK_ON_STACK(&work.work, hpet_work);
+ init_completion(&work.complete);
+ /* FIXME: add schedule_work_on() */
+ schedule_delayed_work_on(cpu, &work.work, 0);
+ wait_for_completion(&work.complete);
+ destroy_timer_on_stack(&work.work.timer);
+ break;
+ case CPU_DEAD:
+ if (hdev) {
+ free_irq(hdev->irq, hdev);
+ hdev->flags &= ~HPET_DEV_USED;
+ per_cpu(cpu_hpet_dev, cpu) = NULL;
+ }
+ break;
+ }
+ return NOTIFY_OK;
+}
+#else
+
+static int hpet_setup_msi_irq(unsigned int irq)
+{
+ return 0;
+}
+static void hpet_msi_capability_lookup(unsigned int start_timer)
+{
+ return;
+}
+
+#ifdef CONFIG_HPET
+static void hpet_reserve_msi_timers(struct hpet_data *hd)
+{
+ return;
+}
+#endif
+
+static int hpet_cpuhp_notify(struct notifier_block *n,
+ unsigned long action, void *hcpu)
+{
+ return NOTIFY_OK;
+}
+
+#endif
/*
* Clock source related code
*/
-static cycle_t read_hpet(void)
+static cycle_t read_hpet(struct clocksource *cs)
{
return (cycle_t)hpet_readl(HPET_COUNTER);
}
.mask = HPET_MASK,
.shift = HPET_SHIFT,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
- .resume = hpet_restart_counter,
+ .resume = hpet_resume_counter,
#ifdef CONFIG_X86_64
.vread = vread_hpet,
#endif
static int hpet_clocksource_register(void)
{
- u64 tmp, start, now;
+ u64 start, now;
cycle_t t1;
/* Start the counter */
- hpet_start_counter();
+ hpet_restart_counter();
/* Verify whether hpet counter works */
- t1 = read_hpet();
+ t1 = hpet_readl(HPET_COUNTER);
rdtscll(start);
/*
rdtscll(now);
} while ((now - start) < 200000UL);
- if (t1 == read_hpet()) {
+ if (t1 == hpet_readl(HPET_COUNTER)) {
printk(KERN_WARNING
"HPET counter not counting. HPET disabled\n");
return -ENODEV;
}
- /* Initialize and register HPET clocksource
- *
- * hpet period is in femto seconds per cycle
- * so we need to convert this to ns/cyc units
- * approximated by mult/2^shift
- *
- * fsec/cyc * 1nsec/1000000fsec = nsec/cyc = mult/2^shift
- * fsec/cyc * 1ns/1000000fsec * 2^shift = mult
- * fsec/cyc * 2^shift * 1nsec/1000000fsec = mult
- * (fsec/cyc << shift)/1000000 = mult
- * (hpet_period << shift)/FSEC_PER_NSEC = mult
+ /*
+ * The definition of mult is (include/linux/clocksource.h)
+ * mult/2^shift = ns/cyc and hpet_period is in units of fsec/cyc
+ * so we first need to convert hpet_period to ns/cyc units:
+ * mult/2^shift = ns/cyc = hpet_period/10^6
+ * mult = (hpet_period * 2^shift)/10^6
+ * mult = (hpet_period << shift)/FSEC_PER_NSEC
*/
- tmp = (u64)hpet_period << HPET_SHIFT;
- do_div(tmp, FSEC_PER_NSEC);
- clocksource_hpet.mult = (u32)tmp;
+ clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT);
clocksource_register(&clocksource_hpet);
*/
int __init hpet_enable(void)
{
- unsigned long id;
+ unsigned int id;
+ int i;
if (!is_hpet_capable())
return 0;
* Read the period and check for a sane value:
*/
hpet_period = hpet_readl(HPET_PERIOD);
+
+ /*
+ * AMD SB700 based systems with spread spectrum enabled use a
+ * SMM based HPET emulation to provide proper frequency
+ * setting. The SMM code is initialized with the first HPET
+ * register access and takes some time to complete. During
+ * this time the config register reads 0xffffffff. We check
+ * for max. 1000 loops whether the config register reads a non
+ * 0xffffffff value to make sure that HPET is up and running
+ * before we go further. A counting loop is safe, as the HPET
+ * access takes thousands of CPU cycles. On non SB700 based
+ * machines this check is only done once and has no side
+ * effects.
+ */
+ for (i = 0; hpet_readl(HPET_CFG) == 0xFFFFFFFF; i++) {
+ if (i == 1000) {
+ printk(KERN_WARNING
+ "HPET config register value = 0xFFFFFFFF. "
+ "Disabling HPET\n");
+ goto out_nohpet;
+ }
+ }
+
if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD)
goto out_nohpet;
* information and the number of channels
*/
id = hpet_readl(HPET_ID);
+ hpet_print_config();
#ifdef CONFIG_HPET_EMULATE_RTC
/*
out_nohpet:
hpet_clear_mapping();
- boot_hpet_disable = 1;
+ hpet_address = 0;
return 0;
}
*/
static __init int hpet_late_init(void)
{
+ int cpu;
+
if (boot_hpet_disable)
return -ENODEV;
hpet_address = force_hpet_address;
hpet_enable();
- if (!hpet_virt_address)
- return -ENODEV;
}
+ if (!hpet_virt_address)
+ return -ENODEV;
+
+ if (hpet_readl(HPET_ID) & HPET_ID_LEGSUP)
+ hpet_msi_capability_lookup(2);
+ else
+ hpet_msi_capability_lookup(0);
+
hpet_reserve_platform_timers(hpet_readl(HPET_ID));
+ hpet_print_config();
+
+ if (hpet_msi_disable)
+ return 0;
+
+ if (boot_cpu_has(X86_FEATURE_ARAT))
+ return 0;
+
+ for_each_online_cpu(cpu) {
+ hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu);
+ }
+
+ /* This notifier should be called after workqueue is ready */
+ hotcpu_notifier(hpet_cpuhp_notify, -20);
return 0;
}
void hpet_disable(void)
{
if (is_hpet_capable()) {
- unsigned long cfg = hpet_readl(HPET_CFG);
+ unsigned int cfg = hpet_readl(HPET_CFG);
if (hpet_legacy_int_enabled) {
cfg &= ~HPET_CFG_LEGACY;
#define RTC_NUM_INTS 1
static unsigned long hpet_rtc_flags;
-static unsigned long hpet_prev_update_sec;
+static int hpet_prev_update_sec;
static struct rtc_time hpet_alarm_time;
static unsigned long hpet_pie_count;
-static unsigned long hpet_t1_cmp;
-static unsigned long hpet_default_delta;
-static unsigned long hpet_pie_delta;
+static u32 hpet_t1_cmp;
+static u32 hpet_default_delta;
+static u32 hpet_pie_delta;
static unsigned long hpet_pie_limit;
static rtc_irq_handler irq_handler;
/*
+ * Check that the hpet counter c1 is ahead of the c2
+ */
+static inline int hpet_cnt_ahead(u32 c1, u32 c2)
+{
+ return (s32)(c2 - c1) < 0;
+}
+
+/*
* Registers a IRQ handler.
*/
int hpet_register_irq_handler(rtc_irq_handler handler)
*/
int hpet_rtc_timer_init(void)
{
- unsigned long cfg, cnt, delta, flags;
+ unsigned int cfg, cnt, delta;
+ unsigned long flags;
if (!is_hpet_enabled())
return 0;
clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC;
clc >>= hpet_clockevent.shift + DEFAULT_RTC_SHIFT;
- hpet_default_delta = (unsigned long) clc;
+ hpet_default_delta = clc;
}
if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit)
hpet_rtc_flags |= bit_mask;
+ if ((bit_mask & RTC_UIE) && !(oldbits & RTC_UIE))
+ hpet_prev_update_sec = -1;
+
if (!oldbits)
hpet_rtc_timer_init();
clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC;
do_div(clc, freq);
clc >>= hpet_clockevent.shift;
- hpet_pie_delta = (unsigned long) clc;
+ hpet_pie_delta = clc;
}
return 1;
}
static void hpet_rtc_timer_reinit(void)
{
- unsigned long cfg, delta;
+ unsigned int cfg, delta;
int lost_ints = -1;
if (unlikely(!hpet_rtc_flags)) {
hpet_t1_cmp += delta;
hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
lost_ints++;
- } while ((long)(hpet_readl(HPET_COUNTER) - hpet_t1_cmp) > 0);
+ } while (!hpet_cnt_ahead(hpet_t1_cmp, hpet_readl(HPET_COUNTER)));
if (lost_ints) {
if (hpet_rtc_flags & RTC_PIE)
hpet_pie_count += lost_ints;
if (printk_ratelimit())
- printk(KERN_WARNING "rtc: lost %d interrupts\n",
+ printk(KERN_WARNING "hpet1: lost %d rtc interrupts\n",
lost_ints);
}
}
if (hpet_rtc_flags & RTC_UIE &&
curr_time.tm_sec != hpet_prev_update_sec) {
- rtc_int_flag = RTC_UF;
+ if (hpet_prev_update_sec >= 0)
+ rtc_int_flag = RTC_UF;
hpet_prev_update_sec = curr_time.tm_sec;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff