Merge master.kernel.org:/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6

[linux-2.6-omap-h63xx.git] / drivers / acpi / processor_idle.c

diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index cdf78943af4db915f1a54da4285cbca2cc1c42ac..a898991f77cbcfb18fc41c481afeca1fc63f0697 100644 (file)
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -51,14 +51,6 @@
 #include <asm/apic.h>
 #endif
 
-/*
- * Include the apic definitions for x86 to have the APIC timer related defines
- * available also for UP (on SMP it gets magically included via linux/smp.h).
- */
-#ifdef CONFIG_X86
-#include <asm/apic.h>
-#endif
-
 #include <asm/io.h>
 #include <asm/uaccess.h>
 
@@ -340,16 +332,18 @@ static void acpi_processor_idle(void)
        int sleep_ticks = 0;
        u32 t1, t2 = 0;
 
-       pr = processors[smp_processor_id()];
-       if (!pr)
-               return;
-
        /*
         * Interrupts must be disabled during bus mastering calculations and
         * for C2/C3 transitions.
         */
        local_irq_disable();
 
+       pr = processors[smp_processor_id()];
+       if (!pr) {
+               local_irq_enable();
+               return;
+       }
+
        /*
         * Check whether we truly need to go idle, or should
         * reschedule:
@@ -481,9 +475,9 @@ static void acpi_processor_idle(void)
                /* Get end time (ticks) */
                t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
 
-#ifdef CONFIG_GENERIC_TIME
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
                /* TSC halts in C2, so notify users */
-               mark_tsc_unstable();
+               mark_tsc_unstable("possible TSC halt in C2");
 #endif
                /* Re-enable interrupts */
                local_irq_enable();
@@ -496,7 +490,17 @@ static void acpi_processor_idle(void)
 
        case ACPI_STATE_C3:
 
-               if (pr->flags.bm_check) {
+               /*
+                * disable bus master
+                * bm_check implies we need ARB_DIS
+                * !bm_check implies we need cache flush
+                * bm_control implies whether we can do ARB_DIS
+                *
+                * That leaves a case where bm_check is set and bm_control is
+                * not set. In that case we cannot do much, we enter C3
+                * without doing anything.
+                */
+               if (pr->flags.bm_check && pr->flags.bm_control) {
                        if (atomic_inc_return(&c3_cpu_count) ==
                            num_online_cpus()) {
                                /*
@@ -505,7 +509,7 @@ static void acpi_processor_idle(void)
                                 */
                                acpi_set_register(ACPI_BITREG_ARB_DISABLE, 1);
                        }
-               } else {
+               } else if (!pr->flags.bm_check) {
                        /* SMP with no shared cache... Invalidate cache  */
                        ACPI_FLUSH_CPU_CACHE();
                }
@@ -517,15 +521,15 @@ static void acpi_processor_idle(void)
                acpi_cstate_enter(cx);
                /* Get end time (ticks) */
                t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
-               if (pr->flags.bm_check) {
+               if (pr->flags.bm_check && pr->flags.bm_control) {
                        /* Enable bus master arbitration */
                        atomic_dec(&c3_cpu_count);
                        acpi_set_register(ACPI_BITREG_ARB_DISABLE, 0);
                }
 
-#ifdef CONFIG_GENERIC_TIME
+#if defined (CONFIG_GENERIC_TIME) && defined (CONFIG_X86_TSC)
                /* TSC halts in C3, so notify users */
-               mark_tsc_unstable();
+               mark_tsc_unstable("TSC halts in C3");
 #endif
                /* Re-enable interrupts */
                local_irq_enable();
@@ -967,9 +971,9 @@ static void acpi_processor_power_verify_c3(struct acpi_processor *pr,
        if (pr->flags.bm_check) {
                /* bus mastering control is necessary */
                if (!pr->flags.bm_control) {
+                       /* In this case we enter C3 without bus mastering */
                        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
-                                         "C3 support requires bus mastering control\n"));
-                       return;
+                               "C3 support without bus mastering control\n"));
                }
        } else {
                /*