diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-02 18:08:03 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-02 18:08:03 -0800 |
| commit | c7b01d3dc297969e66b430830254d447d21bafc9 (patch) | |
| tree | 9a0900b0cd70ccca019fe189cc522e3ca309fa82 /drivers | |
| parent | ad4bfcb1cad7534ae98db3edc5415df97d3e109b (diff) | |
| parent | bfb53ccf1c734b1907df7189eef4c08489827951 (diff) | |
Merge branch 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6
* 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6:
intel_idle: disable Atom/Lincroft HW C-state auto-demotion
intel_idle: disable NHM/WSM HW C-state auto-demotion
Diffstat (limited to 'drivers')
| -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; } |