fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / drivers / clocksource / acpi_pm.c

diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index 7ad3be8..b6bcdbb 100644 (file)
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -54,8 +54,8 @@ static cycle_t acpi_pm_read_verified(void)
                v1 = read_pmtmr();
                v2 = read_pmtmr();
                v3 = read_pmtmr();
-       } while ((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
-                       || (v3 > v1 && v3 < v2));
+       } while (unlikely((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
+                         || (v3 > v1 && v3 < v2)));
 
        return (cycle_t)v2;
 }
@@ -77,11 +77,11 @@ static struct clocksource clocksource_acpi_pm = {
 
 
 #ifdef CONFIG_PCI
-static int acpi_pm_good;
+static int __devinitdata acpi_pm_good;
 static int __init acpi_pm_good_setup(char *__str)
 {
-       acpi_pm_good = 1;
-       return 1;
+       acpi_pm_good = 1;
+       return 1;
 }
 __setup("acpi_pm_good", acpi_pm_good_setup);
 
@@ -138,8 +138,43 @@ static void __devinit acpi_pm_check_graylist(struct pci_dev *dev)
 }
 DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
                        acpi_pm_check_graylist);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_LE,
+                       acpi_pm_check_graylist);
 #endif
 
+#ifndef CONFIG_X86_64
+#include "mach_timer.h"
+#define PMTMR_EXPECTED_RATE \
+  ((CALIBRATE_LATCH * (PMTMR_TICKS_PER_SEC >> 10)) / (CLOCK_TICK_RATE>>10))
+/*
+ * Some boards have the PMTMR running way too fast. We check
+ * the PMTMR rate against PIT channel 2 to catch these cases.
+ */
+static int verify_pmtmr_rate(void)
+{
+       u32 value1, value2;
+       unsigned long count, delta;
+
+       mach_prepare_counter();
+       value1 = read_pmtmr();
+       mach_countup(&count);
+       value2 = read_pmtmr();
+       delta = (value2 - value1) & ACPI_PM_MASK;
+
+       /* Check that the PMTMR delta is within 5% of what we expect */
+       if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
+           delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
+               printk(KERN_INFO "PM-Timer running at invalid rate: %lu%% "
+                       "of normal - aborting.\n",
+                       100UL * delta / PMTMR_EXPECTED_RATE);
+               return -1;
+       }
+
+       return 0;
+}
+#else
+#define verify_pmtmr_rate() (0)
+#endif
 
 static int __init init_acpi_pm_clocksource(void)
 {
@@ -171,6 +206,9 @@ static int __init init_acpi_pm_clocksource(void)
        return -ENODEV;
 
 pm_good:
+       if (verify_pmtmr_rate() != 0)
+               return -ENODEV;
+
        return clocksource_register(&clocksource_acpi_pm);
 }