From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
To: kristen.c.accardi@intel.com, rafael.j.wysocki@intel.com,
len.brown@intel.com
Cc: linux-pm@vger.kernel.org,
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Subject: [PATCH v1 4/6] cpufreq: intel_pstate: Use ACPI perf configuration
Date: Thu, 27 Aug 2015 18:34:24 -0700 [thread overview]
Message-ID: <1440725666-3550-5-git-send-email-srinivas.pandruvada@linux.intel.com> (raw)
In-Reply-To: <1440725666-3550-1-git-send-email-srinivas.pandruvada@linux.intel.com>
Use ACPI _PSS to limit the Intel P State turbo, max and min ratios.
This driver uses acpi processor perf lib calls to register performance.
The following logic is used to adjust Intel P state driver limits:
- If there is no turbo entry in _PSS, then disable Intel P state turbo
and limit to non turbo max
- If the non turbo max ratio is more than _PSS max non turbo value, then
set the max non turbo ratio to _PSS non turbo max
- If the min ratio is less than _PSS min then change the min ratio
matching _PSS min
- Scale the _PSS turbo frequency to max turbo frequency based on control
value.
This feature can be disabled by using kernel parameters:
intel_pstate=no_acpi
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
drivers/cpufreq/Kconfig.x86 | 1 +
drivers/cpufreq/intel_pstate.c | 139 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 140 insertions(+)
diff --git a/drivers/cpufreq/Kconfig.x86 b/drivers/cpufreq/Kconfig.x86
index c59bdcb..adbd1de 100644
--- a/drivers/cpufreq/Kconfig.x86
+++ b/drivers/cpufreq/Kconfig.x86
@@ -5,6 +5,7 @@
config X86_INTEL_PSTATE
bool "Intel P state control"
depends on X86
+ select ACPI_PROCESSOR if ACPI
help
This driver provides a P state for Intel core processors.
The driver implements an internal governor and will become
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index e92a59f..399c6e9 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -34,6 +34,8 @@
#include <asm/cpu_device_id.h>
#include <asm/cpufeature.h>
+#include <acpi/processor.h>
+
#define BYT_RATIOS 0x66a
#define BYT_VIDS 0x66b
#define BYT_TURBO_RATIOS 0x66c
@@ -114,6 +116,9 @@ struct cpudata {
u64 prev_mperf;
u64 prev_tsc;
struct sample sample;
+#if IS_ENABLED(CONFIG_ACPI)
+ struct acpi_processor_performance acpi_perf_data;
+#endif
};
static struct cpudata **all_cpu_data;
@@ -146,6 +151,7 @@ struct cpu_defaults {
static struct pstate_adjust_policy pid_params;
static struct pstate_funcs pstate_funcs;
static int hwp_active;
+static int no_acpi_perf;
struct perf_limits {
int no_turbo;
@@ -173,6 +179,124 @@ static struct perf_limits limits = {
.min_sysfs_pct = 0,
};
+#if IS_ENABLED(CONFIG_ACPI)
+static int intel_pstate_init_perf_limits(struct cpufreq_policy *policy)
+{
+ struct cpudata *cpu;
+ int ret;
+ int min_perf;
+ bool turbo_absent = false;
+ int max_pstate_index;
+ int i;
+
+ cpu = all_cpu_data[policy->cpu];
+
+ if (!cpu->acpi_perf_data.shared_cpu_map &&
+ zalloc_cpumask_var_node(&cpu->acpi_perf_data.shared_cpu_map,
+ GFP_KERNEL, cpu_to_node(policy->cpu))) {
+ return -ENOMEM;
+ }
+
+ ret = acpi_processor_register_performance(&cpu->acpi_perf_data,
+ policy->cpu);
+ if (ret)
+ return ret;
+
+ /* Check if the control value in _PSS is for PERF_CTL MSR */
+ if (cpu->acpi_perf_data.control_register.space_id !=
+ ACPI_ADR_SPACE_FIXED_HARDWARE)
+ return -EIO;
+
+ pr_debug("intel_pstate: CPU%u - ACPI _PSS perf data\n", policy->cpu);
+ for (i = 0; i < cpu->acpi_perf_data.state_count; i++)
+ pr_debug(" %cP%d: %u MHz, %u mW, 0x%x\n",
+ (i == cpu->acpi_perf_data.state ? '*' : ' '), i,
+ (u32) cpu->acpi_perf_data.states[i].core_frequency,
+ (u32) cpu->acpi_perf_data.states[i].power,
+ (u32) cpu->acpi_perf_data.states[i].control);
+
+ /*
+ * If there is only one entry _PSS, simply ignore _PSS and continue as
+ * usual without taking _PSS into account
+ */
+ if (cpu->acpi_perf_data.state_count < 2)
+ return 0;
+
+ /* Check if there is a turbo freq in _PSS */
+ if ((cpu->acpi_perf_data.states[0].control >> 8) <=
+ cpu->pstate.max_pstate) {
+ pr_debug("intel_pstate: no turbo range exists in _PSS\n");
+ limits.no_turbo = limits.turbo_disabled = 1;
+ cpu->pstate.turbo_pstate = cpu->pstate.max_pstate;
+ turbo_absent = true;
+ }
+
+ /* Check if the max non turbo p state < Intel P state max */
+ if (turbo_absent)
+ max_pstate_index = 0;
+ else
+ max_pstate_index = 1;
+ if ((cpu->acpi_perf_data.states[max_pstate_index].control >> 8) <
+ cpu->pstate.max_pstate)
+ cpu->pstate.max_pstate =
+ cpu->acpi_perf_data.states[max_pstate_index].control;
+
+ /* check If min perf > Intel P State min */
+ min_perf = cpu->acpi_perf_data.states[
+ cpu->acpi_perf_data.state_count - 1].control >> 8;
+ if (min_perf > cpu->pstate.min_pstate &&
+ min_perf < cpu->pstate.max_pstate) {
+ cpu->pstate.min_pstate = min_perf;
+ policy->cpuinfo.min_freq = cpu->pstate.min_pstate *
+ cpu->pstate.scaling;
+ }
+
+ if (turbo_absent)
+ policy->cpuinfo.max_freq =
+ cpu->pstate.max_pstate * cpu->pstate.scaling;
+ else {
+ policy->cpuinfo.max_freq =
+ cpu->pstate.turbo_pstate * cpu->pstate.scaling;
+ /* scale freq to intel pstate turbo scale */
+ cpu->acpi_perf_data.states[0].core_frequency =
+ cpu->pstate.scaling *
+ (cpu->acpi_perf_data.states[0].control >> 8);
+ }
+
+ pr_debug("intel_pstate: Updated limits 0x%x 0x%x 0x%x\n",
+ cpu->pstate.min_pstate, cpu->pstate.max_pstate,
+ cpu->pstate.turbo_pstate);
+ pr_debug("intel_pstate: policy max_freq=%d Khz min_freq = %d KHz\n",
+ policy->cpuinfo.max_freq, policy->cpuinfo.min_freq);
+
+ return 0;
+}
+
+static int intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
+{
+ struct cpudata *cpu;
+
+ if (!no_acpi_perf)
+ return 0;
+
+ cpu = all_cpu_data[policy->cpu];
+ acpi_processor_unregister_performance(&cpu->acpi_perf_data,
+ policy->cpu);
+ return 0;
+}
+
+#else
+static int intel_pstate_init_perf_limits(struct cpufreq_policy *policy)
+{
+ return 0;
+}
+
+static int intel_pstate_exit_perf_limits(struct cpufreq_policy *policy)
+{
+ return 0;
+}
+#endif
+
static inline void pid_reset(struct _pid *pid, int setpoint, int busy,
int deadband, int integral) {
pid->setpoint = setpoint;
@@ -1182,18 +1306,30 @@ static int intel_pstate_cpu_init(struct cpufreq_policy *policy)
policy->cpuinfo.min_freq = cpu->pstate.min_pstate * cpu->pstate.scaling;
policy->cpuinfo.max_freq =
cpu->pstate.turbo_pstate * cpu->pstate.scaling;
+ if (!no_acpi_perf)
+ intel_pstate_init_perf_limits(policy);
+ /*
+ * If there is no acpi perf data or error, we ignore and use Intel P
+ * state calculated limits, So this is not fatal error.
+ */
policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
cpumask_set_cpu(policy->cpu, policy->cpus);
return 0;
}
+static int intel_pstate_cpu_exit(struct cpufreq_policy *policy)
+{
+ return intel_pstate_exit_perf_limits(policy);
+}
+
static struct cpufreq_driver intel_pstate_driver = {
.flags = CPUFREQ_CONST_LOOPS,
.verify = intel_pstate_verify_policy,
.setpolicy = intel_pstate_set_policy,
.get = intel_pstate_get,
.init = intel_pstate_cpu_init,
+ .exit = intel_pstate_cpu_exit,
.stop_cpu = intel_pstate_stop_cpu,
.name = "intel_pstate",
};
@@ -1425,6 +1561,9 @@ static int __init intel_pstate_setup(char *str)
force_load = 1;
if (!strcmp(str, "hwp_only"))
hwp_only = 1;
+ if (!strcmp(str, "no_acpi"))
+ no_acpi_perf = 1;
+
return 0;
}
early_param("intel_pstate", intel_pstate_setup);
--
2.4.3
next prev parent reply other threads:[~2015-08-28 1:35 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-28 1:34 [PATCH v1 0/6] Intel P states enhancements Srinivas Pandruvada
2015-08-28 1:34 ` [PATCH v1 1/6] cpufreq: intel_p_state: Fix limiting turbo sub states Srinivas Pandruvada
2015-08-28 1:34 ` [PATCH v1 2/6] cpufreq: intel_pstate: get P1 from TAR when available Srinivas Pandruvada
2015-08-28 1:34 ` [PATCH v1 3/6] cpufreq: intel-pstate: Use separate max pstate for scaling Srinivas Pandruvada
2015-08-28 1:34 ` Srinivas Pandruvada [this message]
2015-08-28 1:34 ` [PATCH v1 5/6] Documentation: kernel_parameters for Intel P state driver Srinivas Pandruvada
2015-08-28 1:34 ` [PATCH v1 6/6] cpufreq: intel_pstate: Avoid calculation for max/min Srinivas Pandruvada
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