From 5dcef694860100fd16885f052591b1268b764d21 Mon Sep 17 00:00:00 2001 From: Len Brown Date: Wed, 6 Apr 2016 17:00:47 -0400 Subject: [PATCH] intel_idle: add BXT support Broxton has all the HSW C-states, except C3. BXT C-state timing is slightly different. Here we trust the IRTL MSRs as authority on maximum C-state latency, and override the driver's tables with the values found in the associated IRTL MSRs. Further we set the target_residency to 1x maximum latency, trusting the hardware demotion logic. Signed-off-by: Len Brown Signed-off-by: Rafael J. Wysocki --- arch/x86/include/asm/msr-index.h | 8 ++ drivers/idle/intel_idle.c | 137 +++++++++++++++++++++++++++++++ 2 files changed, 145 insertions(+) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index b05402ef3b84..73d66fa48638 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -162,6 +162,14 @@ #define MSR_PKG_C9_RESIDENCY 0x00000631 #define MSR_PKG_C10_RESIDENCY 0x00000632 +/* Interrupt Response Limit */ +#define MSR_PKGC3_IRTL 0x0000060a +#define MSR_PKGC6_IRTL 0x0000060b +#define MSR_PKGC7_IRTL 0x0000060c +#define MSR_PKGC8_IRTL 0x00000633 +#define MSR_PKGC9_IRTL 0x00000634 +#define MSR_PKGC10_IRTL 0x00000635 + /* Run Time Average Power Limiting (RAPL) Interface */ #define MSR_RAPL_POWER_UNIT 0x00000606 diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c index c6935de425fa..c96649292b55 100644 --- a/drivers/idle/intel_idle.c +++ b/drivers/idle/intel_idle.c @@ -766,6 +766,67 @@ static struct cpuidle_state knl_cstates[] = { .enter = NULL } }; +static struct cpuidle_state bxt_cstates[] = { + { + .name = "C1-BXT", + .desc = "MWAIT 0x00", + .flags = MWAIT2flg(0x00), + .exit_latency = 2, + .target_residency = 2, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .name = "C1E-BXT", + .desc = "MWAIT 0x01", + .flags = MWAIT2flg(0x01), + .exit_latency = 10, + .target_residency = 20, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .name = "C6-BXT", + .desc = "MWAIT 0x20", + .flags = MWAIT2flg(0x20) | CPUIDLE_FLAG_TLB_FLUSHED, + .exit_latency = 133, + .target_residency = 133, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .name = "C7s-BXT", + .desc = "MWAIT 0x31", + .flags = MWAIT2flg(0x31) | CPUIDLE_FLAG_TLB_FLUSHED, + .exit_latency = 155, + .target_residency = 155, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .name = "C8-BXT", + .desc = "MWAIT 0x40", + .flags = MWAIT2flg(0x40) | CPUIDLE_FLAG_TLB_FLUSHED, + .exit_latency = 1000, + .target_residency = 1000, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .name = "C9-BXT", + .desc = "MWAIT 0x50", + .flags = MWAIT2flg(0x50) | CPUIDLE_FLAG_TLB_FLUSHED, + .exit_latency = 2000, + .target_residency = 2000, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .name = "C10-BXT", + .desc = "MWAIT 0x60", + .flags = MWAIT2flg(0x60) | CPUIDLE_FLAG_TLB_FLUSHED, + .exit_latency = 10000, + .target_residency = 10000, + .enter = &intel_idle, + .enter_freeze = intel_idle_freeze, }, + { + .enter = NULL } +}; + /** * intel_idle * @dev: cpuidle_device @@ -950,6 +1011,11 @@ static const struct idle_cpu idle_cpu_knl = { .state_table = knl_cstates, }; +static const struct idle_cpu idle_cpu_bxt = { + .state_table = bxt_cstates, + .disable_promotion_to_c1e = true, +}; + #define ICPU(model, cpu) \ { X86_VENDOR_INTEL, 6, model, X86_FEATURE_MWAIT, (unsigned long)&cpu } @@ -985,6 +1051,7 @@ static const struct x86_cpu_id intel_idle_ids[] __initconst = { ICPU(0x9e, idle_cpu_skl), ICPU(0x55, idle_cpu_skx), ICPU(0x57, idle_cpu_knl), + ICPU(0x5c, idle_cpu_bxt), {} }; MODULE_DEVICE_TABLE(x86cpu, intel_idle_ids); @@ -1075,6 +1142,73 @@ static void ivt_idle_state_table_update(void) /* else, 1 and 2 socket systems use default ivt_cstates */ } + +/* + * Translate IRTL (Interrupt Response Time Limit) MSR to usec + */ + +static unsigned int irtl_ns_units[] = { + 1, 32, 1024, 32768, 1048576, 33554432, 0, 0 }; + +static unsigned long long irtl_2_usec(unsigned long long irtl) +{ + unsigned long long ns; + + ns = irtl_ns_units[(irtl >> 10) & 0x3]; + + return div64_u64((irtl & 0x3FF) * ns, 1000); +} +/* + * bxt_idle_state_table_update(void) + * + * On BXT, we trust the IRTL to show the definitive maximum latency + * We use the same value for target_residency. + */ +static void bxt_idle_state_table_update(void) +{ + unsigned long long msr; + + rdmsrl(MSR_PKGC6_IRTL, msr); + if (msr) { + unsigned int usec = irtl_2_usec(msr); + + bxt_cstates[2].exit_latency = usec; + bxt_cstates[2].target_residency = usec; + } + + rdmsrl(MSR_PKGC7_IRTL, msr); + if (msr) { + unsigned int usec = irtl_2_usec(msr); + + bxt_cstates[3].exit_latency = usec; + bxt_cstates[3].target_residency = usec; + } + + rdmsrl(MSR_PKGC8_IRTL, msr); + if (msr) { + unsigned int usec = irtl_2_usec(msr); + + bxt_cstates[4].exit_latency = usec; + bxt_cstates[4].target_residency = usec; + } + + rdmsrl(MSR_PKGC9_IRTL, msr); + if (msr) { + unsigned int usec = irtl_2_usec(msr); + + bxt_cstates[5].exit_latency = usec; + bxt_cstates[5].target_residency = usec; + } + + rdmsrl(MSR_PKGC10_IRTL, msr); + if (msr) { + unsigned int usec = irtl_2_usec(msr); + + bxt_cstates[6].exit_latency = usec; + bxt_cstates[6].target_residency = usec; + } + +} /* * sklh_idle_state_table_update(void) * @@ -1130,6 +1264,9 @@ static void intel_idle_state_table_update(void) case 0x3e: /* IVT */ ivt_idle_state_table_update(); break; + case 0x5c: /* BXT */ + bxt_idle_state_table_update(); + break; case 0x5e: /* SKL-H */ sklh_idle_state_table_update(); break;