[PATCH] Fix HPET operation on 32-bit NVIDIA platforms

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / i386 / kernel / acpi / earlyquirk.c

diff --git a/arch/i386/kernel/acpi/earlyquirk.c b/arch/i386/kernel/acpi/earlyquirk.c
index 2e3b643a4dc4df57552562015349c7657ca5b5d6..1649a175a206ab4bd6ed0add0040580ff83d036e 100644 (file)
--- a/arch/i386/kernel/acpi/earlyquirk.c
+++ b/arch/i386/kernel/acpi/earlyquirk.c
@@ -5,17 +5,34 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/pci.h>
+#include <linux/acpi.h>
+
 #include <asm/pci-direct.h>
 #include <asm/acpi.h>
 #include <asm/apic.h>
 
+#ifdef CONFIG_ACPI
+
+static int nvidia_hpet_detected __initdata;
+
+static int __init nvidia_hpet_check(unsigned long phys, unsigned long size)
+{
+       nvidia_hpet_detected = 1;
+       return 0;
+}
+#endif
+
 static int __init check_bridge(int vendor, int device)
 {
 #ifdef CONFIG_ACPI
-       /* According to Nvidia all timer overrides are bogus. Just ignore
-          them all. */
+       /* According to Nvidia all timer overrides are bogus unless HPET
+          is enabled. */
        if (vendor == PCI_VENDOR_ID_NVIDIA) {
-               acpi_skip_timer_override = 1;
+               nvidia_hpet_detected = 0;
+               acpi_table_parse(ACPI_HPET, nvidia_hpet_check);
+               if (nvidia_hpet_detected == 0) {
+                       acpi_skip_timer_override = 1;
+               }
        }
 #endif
        if (vendor == PCI_VENDOR_ID_ATI && timer_over_8254 == 1) {