From b34ef932d79ac2a36e1d7ba2742e5d4ba54efa3c Mon Sep 17 00:00:00 2001 From: Dasaratharaman Chandramouli Date: Fri, 10 Apr 2015 10:22:18 -0700 Subject: [PATCH] intel_pstate: Knights Landing support 1. Add Knights Landing (KNL) CPUID to the list of CPUIDs supported by the intel_pstate driver. 2. Add a new cpu_default structure for KNL since KNL has a slightly different mechanism to get turbo pstates from MSRs. Signed-off-by: Dasaratharaman Chandramouli Signed-off-by: Kristen Carlson Accardi [ rjw: Subject and changelog ] Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 8006d86da397..c5b81beccc8e 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -614,6 +614,19 @@ static void core_set_pstate(struct cpudata *cpudata, int pstate) wrmsrl_on_cpu(cpudata->cpu, MSR_IA32_PERF_CTL, val); } +static int knl_get_turbo_pstate(void) +{ + u64 value; + int nont, ret; + + rdmsrl(MSR_NHM_TURBO_RATIO_LIMIT, value); + nont = core_get_max_pstate(); + ret = (((value) >> 8) & 0xFF); + if (ret <= nont) + ret = nont; + return ret; +} + static struct cpu_defaults core_params = { .pid_policy = { .sample_rate_ms = 10, @@ -651,6 +664,23 @@ static struct cpu_defaults byt_params = { }, }; +static struct cpu_defaults knl_params = { + .pid_policy = { + .sample_rate_ms = 10, + .deadband = 0, + .setpoint = 97, + .p_gain_pct = 20, + .d_gain_pct = 0, + .i_gain_pct = 0, + }, + .funcs = { + .get_max = core_get_max_pstate, + .get_min = core_get_min_pstate, + .get_turbo = knl_get_turbo_pstate, + .set = core_set_pstate, + }, +}; + static void intel_pstate_get_min_max(struct cpudata *cpu, int *min, int *max) { int max_perf = cpu->pstate.turbo_pstate; @@ -865,6 +895,7 @@ static const struct x86_cpu_id intel_pstate_cpu_ids[] = { ICPU(0x4e, core_params), ICPU(0x4f, core_params), ICPU(0x56, core_params), + ICPU(0x57, knl_params), {} }; MODULE_DEVICE_TABLE(x86cpu, intel_pstate_cpu_ids);