1 files changed, 49 insertions, 28 deletions

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index dedc2bddf7a5..ba6e65884603 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -33,6 +33,7 @@
  * HPET address is set in acpi/boot.c, when an ACPI entry exists
  */
 unsigned long                           hpet_address;
+u8                                      hpet_blockid; /* OS timer block num */
 #ifdef CONFIG_PCI_MSI
 static unsigned long                    hpet_num_timers;
 #endif
@@ -47,12 +48,12 @@ 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);
 }
@@ -167,7 +168,7 @@ do {								\
 
 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];
@@ -205,7 +206,7 @@ static void hpet_reserve_platform_timers(unsigned long id)
 
 }
 #else
-static void hpet_reserve_platform_timers(unsigned long id) { }
+static void hpet_reserve_platform_timers(unsigned int id) { }
 #endif
 
 /*
@@ -246,7 +247,7 @@ static void hpet_reset_counter(void)
 
 static void hpet_start_counter(void)
 {
-        unsigned long cfg = hpet_readl(HPET_CFG);
+        unsigned int cfg = hpet_readl(HPET_CFG);
         cfg |= HPET_CFG_ENABLE;
         hpet_writel(cfg, HPET_CFG);
 }
@@ -271,7 +272,7 @@ static void hpet_resume_counter(void)
 
 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);
@@ -314,7 +315,7 @@ 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) {
@@ -323,7 +324,7 @@ static void hpet_set_mode(enum clock_event_mode mode,
                 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;
@@ -339,7 +340,7 @@ static void hpet_set_mode(enum clock_event_mode mode,
                  * (See AMD-8111 HyperTransport I/O Hub Data Sheet,
                  * Publication # 24674)
                  */
-                hpet_writel((unsigned long) delta, HPET_Tn_CMP(timer));
+                hpet_writel((unsigned int) delta, HPET_Tn_CMP(timer));
                 hpet_start_counter();
                 hpet_print_config();
                 break;
@@ -383,13 +384,24 @@ static int hpet_next_event(unsigned long delta,
         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,
@@ -415,7 +427,7 @@ static struct hpet_dev	*hpet_devs;
 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));
@@ -425,7 +437,7 @@ void hpet_msi_unmask(unsigned int irq)
 
 void hpet_msi_mask(unsigned int irq)
 {
-        unsigned long cfg;
+        unsigned int cfg;
         struct hpet_dev *hdev = get_irq_data(irq);
 
         /* mask it */
@@ -467,7 +479,7 @@ static int hpet_msi_next_event(unsigned long delta,
 
 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;
         }
@@ -584,6 +596,8 @@ static void hpet_msi_capability_lookup(unsigned int start_timer)
         unsigned int num_timers_used = 0;
         int i;
 
+        if (boot_cpu_has(X86_FEATURE_ARAT))
+                return;
         id = hpet_readl(HPET_ID);
 
         num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT);
@@ -598,7 +612,7 @@ static void hpet_msi_capability_lookup(unsigned int start_timer)
 
         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))
@@ -813,7 +827,7 @@ static int hpet_clocksource_register(void)
  */
 int __init hpet_enable(void)
 {
-        unsigned long id;
+        unsigned int id;
         int i;
 
         if (!is_hpet_capable())
@@ -872,10 +886,8 @@ int __init hpet_enable(void)
 
         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:
@@ -908,9 +920,17 @@ static __init int hpet_late_init(void)
         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 (boot_cpu_has(X86_FEATURE_ARAT))
+                return 0;
+
         for_each_online_cpu(cpu) {
                 hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu);
         }
@@ -925,7 +945,7 @@ fs_initcall(hpet_late_init);
 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;
@@ -965,8 +985,8 @@ static int hpet_prev_update_sec;
 static struct rtc_time hpet_alarm_time;
 static unsigned long hpet_pie_count;
 static u32 hpet_t1_cmp;
-static unsigned long hpet_default_delta;
-static unsigned long hpet_pie_delta;
+static u32 hpet_default_delta;
+static u32 hpet_pie_delta;
 static unsigned long hpet_pie_limit;
 
 static rtc_irq_handler irq_handler;
@@ -1017,7 +1037,8 @@ EXPORT_SYMBOL_GPL(hpet_unregister_irq_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;
@@ -1027,7 +1048,7 @@ int hpet_rtc_timer_init(void)
 
                 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)
@@ -1113,7 +1134,7 @@ int hpet_set_periodic_freq(unsigned long freq)
                 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;
 }
@@ -1127,7 +1148,7 @@ EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq);
 
 static void hpet_rtc_timer_reinit(void)
 {
-        unsigned long cfg, delta;
+        unsigned int cfg, delta;
         int lost_ints = -1;
 
         if (unlikely(!hpet_rtc_flags)) {