diff options
| -rw-r--r-- | drivers/idle/intel_idle.c | 117 |
1 files changed, 116 insertions, 1 deletions
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index 256c2d42e350..a80e1f520293 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -199,6 +199,43 @@ static __cpuidle int intel_idle_xstate(struct cpuidle_device *dev, return __intel_idle(dev, drv, index); } +static __always_inline int __intel_idle_hlt(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + raw_safe_halt(); + raw_local_irq_disable(); + return index; +} + +/** + * intel_idle_hlt - Ask the processor to enter the given idle state using hlt. + * @dev: cpuidle device of the target CPU. + * @drv: cpuidle driver (assumed to point to intel_idle_driver). + * @index: Target idle state index. + * + * Use the HLT instruction to notify the processor that the CPU represented by + * @dev is idle and it can try to enter the idle state corresponding to @index. + * + * Must be called under local_irq_disable(). + */ +static __cpuidle int intel_idle_hlt(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + return __intel_idle_hlt(dev, drv, index); +} + +static __cpuidle int intel_idle_hlt_irq_on(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + int ret; + + raw_local_irq_enable(); + ret = __intel_idle_hlt(dev, drv, index); + raw_local_irq_disable(); + + return ret; +} + /** * intel_idle_s2idle - Ask the processor to enter the given idle state. * @dev: cpuidle device of the target CPU. @@ -1242,6 +1279,18 @@ static struct cpuidle_state snr_cstates[] __initdata = { .enter = NULL } }; +static struct cpuidle_state vmguest_cstates[] __initdata = { + { + .name = "C1", + .desc = "HLT", + .flags = MWAIT2flg(0x00) | CPUIDLE_FLAG_IRQ_ENABLE, + .exit_latency = 5, + .target_residency = 10, + .enter = &intel_idle_hlt, }, + { + .enter = NULL } +}; + static const struct idle_cpu idle_cpu_nehalem __initconst = { .state_table = nehalem_cstates, .auto_demotion_disable_flags = NHM_C1_AUTO_DEMOTE | NHM_C3_AUTO_DEMOTE, @@ -1841,6 +1890,16 @@ static bool __init intel_idle_verify_cstate(unsigned int mwait_hint) static void state_update_enter_method(struct cpuidle_state *state, int cstate) { + if (state->enter == intel_idle_hlt) { + if (force_irq_on) { + pr_info("forced intel_idle_irq for state %d\n", cstate); + state->enter = intel_idle_hlt_irq_on; + } + return; + } + if (state->enter == intel_idle_hlt_irq_on) + return; /* no update scenarios */ + if (state->flags & CPUIDLE_FLAG_INIT_XSTATE) { /* * Combining with XSTATE with IBRS or IRQ_ENABLE flags @@ -1874,6 +1933,21 @@ static void state_update_enter_method(struct cpuidle_state *state, int cstate) } } +/* + * For mwait based states, we want to verify the cpuid data to see if the state + * is actually supported by this specific CPU. + * For non-mwait based states, this check should be skipped. + */ +static bool should_verify_mwait(struct cpuidle_state *state) +{ + if (state->enter == intel_idle_hlt) + return false; + if (state->enter == intel_idle_hlt_irq_on) + return false; + + return true; +} + static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv) { int cstate; @@ -1922,7 +1996,7 @@ static void __init intel_idle_init_cstates_icpu(struct cpuidle_driver *drv) } mwait_hint = flg2MWAIT(cpuidle_state_table[cstate].flags); - if (!intel_idle_verify_cstate(mwait_hint)) + if (should_verify_mwait(&cpuidle_state_table[cstate]) && !intel_idle_verify_cstate(mwait_hint)) continue; /* Structure copy. */ @@ -2056,6 +2130,45 @@ static void __init intel_idle_cpuidle_devices_uninit(void) cpuidle_unregister_device(per_cpu_ptr(intel_idle_cpuidle_devices, i)); } +static int __init intel_idle_vminit(const struct x86_cpu_id *id) +{ + int retval; + + cpuidle_state_table = vmguest_cstates; + + icpu = (const struct idle_cpu *)id->driver_data; + + pr_debug("v" INTEL_IDLE_VERSION " model 0x%X\n", + boot_cpu_data.x86_model); + + intel_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); + if (!intel_idle_cpuidle_devices) + return -ENOMEM; + + intel_idle_cpuidle_driver_init(&intel_idle_driver); + + retval = cpuidle_register_driver(&intel_idle_driver); + if (retval) { + struct cpuidle_driver *drv = cpuidle_get_driver(); + printk(KERN_DEBUG pr_fmt("intel_idle yielding to %s\n"), + drv ? drv->name : "none"); + goto init_driver_fail; + } + + retval = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "idle/intel:online", + intel_idle_cpu_online, NULL); + if (retval < 0) + goto hp_setup_fail; + + return 0; +hp_setup_fail: + intel_idle_cpuidle_devices_uninit(); + cpuidle_unregister_driver(&intel_idle_driver); +init_driver_fail: + free_percpu(intel_idle_cpuidle_devices); + return retval; +} + static int __init intel_idle_init(void) { const struct x86_cpu_id *id; @@ -2074,6 +2187,8 @@ static int __init intel_idle_init(void) id = x86_match_cpu(intel_idle_ids); if (id) { if (!boot_cpu_has(X86_FEATURE_MWAIT)) { + if (boot_cpu_has(X86_FEATURE_HYPERVISOR)) + return intel_idle_vminit(id); pr_debug("Please enable MWAIT in BIOS SETUP\n"); return -ENODEV; } |