diff options
| author | Ingo Molnar <mingo@elte.hu> | 2011-03-04 11:12:24 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2011-03-04 11:12:26 +0100 |
| commit | e0a92c17470775cd85bac52f5372ccc3dc58254a (patch) | |
| tree | 9339da8754084bed50b941b018706b75482025cb /drivers/idle/intel_idle.c | |
| parent | 544b4a1f309d18f40969dbab7e08bafd136b2f55 (diff) | |
| parent | 0c3b9168017cbad2c4af3dd65ec93fe646eeaa62 (diff) | |
Merge branch 'sched/urgent' into sched/core
Merge reason: Add fixes before applying dependent patches.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/idle/intel_idle.c')
| -rw-r--r-- | drivers/idle/intel_idle.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 1fa091e0569..4a5c4a44ffb 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -62,6 +62,7 @@ #include <linux/notifier.h> #include <linux/cpu.h> #include <asm/mwait.h> +#include <asm/msr.h> #define INTEL_IDLE_VERSION "0.4" #define PREFIX "intel_idle: " @@ -85,6 +86,12 @@ static int intel_idle(struct cpuidle_device *dev, struct cpuidle_state *state); static struct cpuidle_state *cpuidle_state_table; /* + * Hardware C-state auto-demotion may not always be optimal. + * Indicate which enable bits to clear here. + */ +static unsigned long long auto_demotion_disable_flags; + +/* * Set this flag for states where the HW flushes the TLB for us * and so we don't need cross-calls to keep it consistent. * If this flag is set, SW flushes the TLB, so even if the @@ -281,6 +288,15 @@ static struct notifier_block setup_broadcast_notifier = { .notifier_call = setup_broadcast_cpuhp_notify, }; +static void auto_demotion_disable(void *dummy) +{ + unsigned long long msr_bits; + + rdmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); + msr_bits &= ~auto_demotion_disable_flags; + wrmsrl(MSR_NHM_SNB_PKG_CST_CFG_CTL, msr_bits); +} + /* * intel_idle_probe() */ @@ -324,11 +340,17 @@ static int intel_idle_probe(void) case 0x25: /* Westmere */ case 0x2C: /* Westmere */ cpuidle_state_table = nehalem_cstates; + auto_demotion_disable_flags = + (NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE); break; case 0x1C: /* 28 - Atom Processor */ + cpuidle_state_table = atom_cstates; + break; + case 0x26: /* 38 - Lincroft Atom Processor */ cpuidle_state_table = atom_cstates; + auto_demotion_disable_flags = ATM_LNC_C6_AUTO_DEMOTE; break; case 0x2A: /* SNB */ @@ -436,6 +458,8 @@ static int intel_idle_cpuidle_devices_init(void) return -EIO; } } + if (auto_demotion_disable_flags) + smp_call_function(auto_demotion_disable, NULL, 1); return 0; } |