Merge branches 'timers/clocksource', 'timers/hrtimers', 'timers/nohz', 'timers/ntp...

[safe/jmp/linux-2.6] / drivers / clocksource / acpi_pm.c

diff --git a/drivers/clocksource/acpi_pm.c b/drivers/clocksource/acpi_pm.c
index d42060e..c201710 100644 (file)
--- a/drivers/clocksource/acpi_pm.c
+++ b/drivers/clocksource/acpi_pm.c
@@ -21,12 +21,13 @@
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/pci.h>
+#include <linux/delay.h>
 #include <asm/io.h>
 
 /*
  * The I/O port the PMTMR resides at.
  * The location is detected during setup_arch(),
- * in arch/i386/acpi/boot.c
+ * in arch/i386/kernel/acpi/boot.c
  */
 u32 pmtmr_ioport __read_mostly;
 
@@ -71,7 +72,7 @@ static struct clocksource clocksource_acpi_pm = {
        .rating         = 200,
        .read           = acpi_pm_read,
        .mask           = (cycle_t)ACPI_PM_MASK,
-       .mult           = 0, /*to be caluclated*/
+       .mult           = 0, /*to be calculated*/
        .shift          = 22,
        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
 
@@ -90,7 +91,7 @@ __setup("acpi_pm_good", acpi_pm_good_setup);
 static inline void acpi_pm_need_workaround(void)
 {
        clocksource_acpi_pm.read = acpi_pm_read_slow;
-       clocksource_acpi_pm.rating = 110;
+       clocksource_acpi_pm.rating = 120;
 }
 
 /*
@@ -105,14 +106,11 @@ static inline void acpi_pm_need_workaround(void)
  */
 static void __devinit acpi_pm_check_blacklist(struct pci_dev *dev)
 {
-       u8 rev;
-
        if (acpi_pm_good)
                return;
 
-       pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
        /* the bug has been fixed in PIIX4M */
-       if (rev < 3) {
+       if (dev->revision < 3) {
                printk(KERN_WARNING "* Found PM-Timer Bug on the chipset."
                       " Due to workarounds for a bug,\n"
                       "* this clock source is slow. Consider trying"
@@ -154,13 +152,13 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_LE,
  */
 static int verify_pmtmr_rate(void)
 {
-       u32 value1, value2;
+       cycle_t value1, value2;
        unsigned long count, delta;
 
        mach_prepare_counter();
-       value1 = read_pmtmr();
+       value1 = clocksource_acpi_pm.read();
        mach_countup(&count);
-       value2 = read_pmtmr();
+       value2 = clocksource_acpi_pm.read();
        delta = (value2 - value1) & ACPI_PM_MASK;
 
        /* Check that the PMTMR delta is within 5% of what we expect */
@@ -178,10 +176,15 @@ static int verify_pmtmr_rate(void)
 #define verify_pmtmr_rate() (0)
 #endif
 
+/* Number of monotonicity checks to perform during initialization */
+#define ACPI_PM_MONOTONICITY_CHECKS 10
+/* Number of reads we try to get two different values */
+#define ACPI_PM_READ_CHECKS 10000
+
 static int __init init_acpi_pm_clocksource(void)
 {
-       u32 value1, value2;
-       unsigned int i;
+       cycle_t value1, value2;
+       unsigned int i, j = 0;
 
        if (!pmtmr_ioport)
                return -ENODEV;
@@ -190,24 +193,29 @@ static int __init init_acpi_pm_clocksource(void)
                                                clocksource_acpi_pm.shift);
 
        /* "verify" this timing source: */
-       value1 = read_pmtmr();
-       for (i = 0; i < 10000; i++) {
-               value2 = read_pmtmr();
-               if (value2 == value1)
-                       continue;
-               if (value2 > value1)
-                       goto pm_good;
-               if ((value2 < value1) && ((value2) < 0xFFF))
-                       goto pm_good;
-               printk(KERN_INFO "PM-Timer had inconsistent results:"
-                       " 0x%#x, 0x%#x - aborting.\n", value1, value2);
-               return -EINVAL;
+       for (j = 0; j < ACPI_PM_MONOTONICITY_CHECKS; j++) {
+               udelay(100 * j);
+               value1 = clocksource_acpi_pm.read();
+               for (i = 0; i < ACPI_PM_READ_CHECKS; i++) {
+                       value2 = clocksource_acpi_pm.read();
+                       if (value2 == value1)
+                               continue;
+                       if (value2 > value1)
+                               break;
+                       if ((value2 < value1) && ((value2) < 0xFFF))
+                               break;
+                       printk(KERN_INFO "PM-Timer had inconsistent results:"
+                              " 0x%#llx, 0x%#llx - aborting.\n",
+                              value1, value2);
+                       return -EINVAL;
+               }
+               if (i == ACPI_PM_READ_CHECKS) {
+                       printk(KERN_INFO "PM-Timer failed consistency check "
+                              " (0x%#llx) - aborting.\n", value1);
+                       return -ENODEV;
+               }
        }
-       printk(KERN_INFO "PM-Timer had no reasonable result:"
-                       " 0x%#x - aborting.\n", value1);
-       return -ENODEV;
 
-pm_good:
        if (verify_pmtmr_rate() != 0)
                return -ENODEV;
 
@@ -218,3 +226,25 @@ pm_good:
  * but we still need to load before device_initcall
  */
 fs_initcall(init_acpi_pm_clocksource);
+
+/*
+ * Allow an override of the IOPort. Stupid BIOSes do not tell us about
+ * the PMTimer, but we might know where it is.
+ */
+static int __init parse_pmtmr(char *arg)
+{
+       unsigned long base;
+
+       if (strict_strtoul(arg, 16, &base))
+               return -EINVAL;
+#ifdef CONFIG_X86_64
+       if (base > UINT_MAX)
+               return -ERANGE;
+#endif
+       printk(KERN_INFO "PMTMR IOPort override: 0x%04x -> 0x%04lx\n",
+              pmtmr_ioport, base);
+       pmtmr_ioport = base;
+
+       return 1;
+}
+__setup("pmtmr=", parse_pmtmr);