#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/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 1000000L
+#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;
+unsigned long hpet_num_timers;
+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)
{
static int boot_hpet_disable;
int hpet_force_user;
-static int __init hpet_setup(char* str)
+static int __init hpet_setup(char *str)
{
if (str) {
if (!strncmp("disable", str, 7))
static inline int is_hpet_capable(void)
{
- return (!boot_hpet_disable && hpet_address);
+ return !boot_hpet_disable && hpet_address;
}
/*
* timer 0 and timer 1 in case of RTC emulation.
*/
#ifdef CONFIG_HPET
+
+static void hpet_reserve_msi_timers(struct hpet_data *hd);
+
static void hpet_reserve_platform_timers(unsigned long id)
{
struct hpet __iomem *hpet = hpet_virt_address;
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;
+ 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
hd.hd_irq[1] = HPET_LEGACY_RTC;
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;
+ 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);
}
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;
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;
+ 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);
+ cfg = hpet_readl(HPET_Tn_CFG(timer));
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));
/*
* The first write after writing TN_SETVAL to the
* config register sets the counter value, the second
* write sets the period.
*/
- hpet_writel(cmp, HPET_T0_CMP);
+ hpet_writel(cmp, HPET_Tn_CMP(timer));
udelay(1);
- hpet_writel((unsigned long) delta, HPET_T0_CMP);
+ hpet_writel((unsigned long) delta, HPET_Tn_CMP(timer));
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_cpu(hdev->cpu));
+ enable_irq(hdev->irq);
+ }
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)
{
u32 cnt;
cnt = hpet_readl(HPET_COUNTER);
cnt += (u32) delta;
- hpet_writel(cnt, HPET_T0_CMP);
+ hpet_writel(cnt, HPET_Tn_CMP(timer));
/*
* We need to read back the CMP register to make sure that
* what we wrote hit the chip before we compare it to the
* counter.
*/
- WARN_ON((u32)hpet_readl(HPET_T0_CMP) != cnt);
+ WARN_ON_ONCE((u32)hpet_readl(HPET_Tn_CMP(timer)) != cnt);
return (s32)((u32)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 long 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 long 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)) {
+ 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_DISABLED|IRQF_NOBALANCING, dev->name, dev))
+ return -1;
+
+ disable_irq(dev->irq);
+ irq_set_affinity(dev->irq, cpumask_of_cpu(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_cpu(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
+
+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;
+
+ id = hpet_readl(HPET_ID);
+
+ num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT);
+ num_timers++; /* Value read out starts from 0 */
+
+ 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 long 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(&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);
+ 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
*/
if (id & HPET_ID_LEGSUP) {
hpet_legacy_clockevent_register();
+ hpet_msi_capability_lookup(2);
return 1;
}
+ hpet_msi_capability_lookup(0);
return 0;
out_nohpet:
*/
static __init int hpet_late_init(void)
{
+ int cpu;
+
if (boot_hpet_disable)
return -ENODEV;
hpet_reserve_platform_timers(hpet_readl(HPET_ID));
+ 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;
}
fs_initcall(hpet_late_init);
git.samba.org / sfrench / cifs-2.6.git / blobdiff