#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/cpu.h>
* HPET address is set in acpi/boot.c, when an ACPI entry exists
*/
unsigned long hpet_address;
-unsigned long hpet_num_timers;
+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 {
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);
}
*/
static int boot_hpet_disable;
int hpet_force_user;
+static int hpet_verbose;
static int __init hpet_setup(char *str)
{
boot_hpet_disable = 1;
if (!strncmp("force", str, 5))
hpet_force_user = 1;
+ if (!strncmp("verbose", str, 7))
+ hpet_verbose = 1;
}
return 1;
}
}
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.
static void hpet_reserve_msi_timers(struct hpet_data *hd);
-static void hpet_reserve_platform_timers(unsigned long id)
+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];
}
#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);
* 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_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) {
case CLOCK_EVT_MODE_PERIODIC:
+ 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;
+ 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_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_Tn_CMP(timer));
udelay(1);
- hpet_writel((unsigned long) delta, HPET_Tn_CMP(timer));
+ /*
+ * 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((unsigned int) delta, HPET_Tn_CMP(timer));
+ hpet_start_counter();
+ hpet_print_config();
break;
case CLOCK_EVT_MODE_ONESHOT:
irq_set_affinity(hdev->irq, cpumask_of(hdev->cpu));
enable_irq(hdev->irq);
}
+ hpet_print_config();
break;
}
}
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.
+ * 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_ON_ONCE((u32)hpet_readl(HPET_Tn_CMP(timer)) != cnt);
+ WARN_ONCE(hpet_readl(HPET_Tn_CMP(timer)) != cnt,
+ KERN_WARNING "hpet: compare register read back failed.\n");
- return (s32)((u32)hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0;
+ return (s32)(hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0;
}
static void hpet_legacy_set_mode(enum clock_event_mode mode,
void hpet_msi_unmask(unsigned int irq)
{
struct hpet_dev *hdev = get_irq_data(irq);
- unsigned long cfg;
+ unsigned int cfg;
/* unmask it */
cfg = hpet_readl(HPET_Tn_CFG(hdev->num));
void hpet_msi_mask(unsigned int irq)
{
- unsigned long cfg;
+ unsigned int cfg;
struct hpet_dev *hdev = get_irq_data(irq);
/* mask it */
static int hpet_setup_msi_irq(unsigned int irq)
{
- if (arch_setup_hpet_msi(irq)) {
+ if (arch_setup_hpet_msi(irq, hpet_blockid)) {
destroy_irq(irq);
return -EINVAL;
}
{
if (request_irq(dev->irq, hpet_interrupt_handler,
- IRQF_DISABLED|IRQF_NOBALANCING, dev->name, dev))
+ IRQF_TIMER | IRQF_DISABLED | IRQF_NOBALANCING,
+ dev->name, dev))
return -1;
disable_irq(dev->irq);
/* 5 usec minimum reprogramming delta. */
evt->min_delta_ns = 5000;
- evt->cpumask = cpumask_of_cpu(hdev->cpu);
+ evt->cpumask = cpumask_of(hdev->cpu);
clockevents_register_device(evt);
}
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)
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));
+ unsigned int cfg = hpet_readl(HPET_Tn_CFG(i));
/* Only consider HPET timer with MSI support */
if (!(cfg & HPET_TN_FSB_CAP))
switch (action & 0xf) {
case CPU_ONLINE:
- INIT_DELAYED_WORK(&work.work, hpet_work);
+ 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) {
/*
* 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
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;
*/
int __init hpet_enable(void)
{
- unsigned long id;
+ unsigned int id;
int i;
if (!is_hpet_capable())
* information and the number of channels
*/
id = hpet_readl(HPET_ID);
+ hpet_print_config();
#ifdef CONFIG_HPET_EMULATE_RTC
/*
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:
hpet_clear_mapping();
- boot_hpet_disable = 1;
+ hpet_address = 0;
return 0;
}
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);
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;
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)
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)