@@ -64,6 +64,25 @@ static inline int ceiling_fp(int32_t x)
return ret;
}
+/**
+ * struct sample - Store performance sample
+ * @core_pct_busy: Ratio of APERF/MPERF in percent, which is actual
+ * performance during last sample period
+ * @busy_scaled: Scaled busy value which is used to calculate next
+ * P state. This can be different than core_pct_busy
+ * to account for cpu idle period
+ * @aperf: Difference of actual performance frequency clock count
+ * read from APERF MSR between last and current sample
+ * @mperf: Difference of maximum performance frequency clock count
+ * read from MPERF MSR between last and current sample
+ * @tsc: Difference of time stamp counter between last and
+ * current sample
+ * @freq: Effective frequency calculated from APERF/MPERF
+ * @time: Current time from scheduler
+ *
+ * This structure is used in the cpudata structure to store performance sample
+ * data for choosing next P State.
+ */
struct sample {
int32_t core_pct_busy;
int32_t busy_scaled;
@@ -74,6 +93,20 @@ struct sample {
u64 time;
};
+/**
+ * struct pstate_data - Store P state data
+ * @current_pstate: Current requested P state
+ * @min_pstate: Min P state possible for this platform
+ * @max_pstate: Max P state possible for this platform
+ * @max_pstate_physical:This is physical Max P state for a processor
+ * This can be higher than the max_pstate which can
+ * be limited by platform thermal design power limits
+ * @scaling: Scaling factor to convert frequency to cpufreq
+ * frequency units
+ * @turbo_pstate: Max Turbo P state possible for this platform
+ *
+ * Stores the per cpu model P state limits and current P state.
+ */
struct pstate_data {
int current_pstate;
int min_pstate;
@@ -83,6 +116,19 @@ struct pstate_data {
int turbo_pstate;
};
+/**
+ * struct vid_data - Stores voltage information data
+ * @min: VID data for this platform corresponding to
+ * the lowest P state
+ * @max: VID data corresponding to the highest P State.
+ * @turbo: VID data for turbo P state
+ * @ratio: Ratio of (vid max - vid min) /
+ * (max P state - Min P State)
+ *
+ * Stores the voltage data for DVFS (Dynamic Voltage and Frequency Scaling)
+ * This data is used in Atom platforms, where in addition to target P state,
+ * the voltage data needs to be specified to select next P State.
+ */
struct vid_data {
int min;
int max;
@@ -90,6 +136,18 @@ struct vid_data {
int32_t ratio;
};
+/**
+ * struct _pid - Stores PID data
+ * @setpoint: Target set point for busyness or performance
+ * @integral: Storage for accumulated error values
+ * @p_gain: PID proportional gain
+ * @i_gain: PID integral gain
+ * @d_gain: PID derivative gain
+ * @deadband: PID deadband
+ * @last_err: Last error storage for integral part of PID calculation
+ *
+ * Stores PID coefficients and last error for PID controller.
+ */
struct _pid {
int setpoint;
int32_t integral;
@@ -100,6 +158,23 @@ struct _pid {
int32_t last_err;
};
+/**
+ * struct cpudata - Per CPU instance data storage
+ * @cpu: CPU number for this instance data
+ * @update_util: CPUFreq utility callback information
+ * @pstate: Stores P state limits for this CPU
+ * @vid: Stores VID limits for this CPU
+ * @pid: Stores PID parameters for this CPU
+ * @last_sample_time: Last Sample time
+ * @prev_aperf: Last APERF value read from APERF MSR
+ * @prev_mperf: Last MPERF value read from MPERF MSR
+ * @prev_tsc: Last timestamp counter (TSC) value
+ * @prev_cummulative_iowait: IO Wait time difference from last and
+ * current sample
+ * @sample: Storage for storing last Sample data
+ *
+ * This structure stores per CPU instance data for all CPUs.
+ */
struct cpudata {
int cpu;
@@ -118,6 +193,19 @@ struct cpudata {
};
static struct cpudata **all_cpu_data;
+
+/**
+ * struct pid_adjust_policy - Stores static PID configuration data
+ * @sample_rate_ms: PID calculation sample rate in ms
+ * @sample_rate_ns: Sample rate calculation in ns
+ * @deadband: PID deadband
+ * @setpoint: PID Setpoint
+ * @p_gain_pct: PID proportional gain
+ * @i_gain_pct: PID integral gain
+ * @d_gain_pct: PID derivative gain
+ *
+ * Stores per CPU model static PID configuration data.
+ */
struct pstate_adjust_policy {
int sample_rate_ms;
s64 sample_rate_ns;
@@ -128,6 +216,20 @@ struct pstate_adjust_policy {
int i_gain_pct;
};
+/**
+ * struct pstate_funcs - Per CPU model specific callbacks
+ * @get_max: Callback to get maximum non turbo effective P state
+ * @get_max_physical: Callback to get maximum non turbo physical P state
+ * @get_min: Callback to get minimum P state
+ * @get_turbo: Callback to get turbo P state
+ * @get_scaling: Callback to get frequency scaling factor
+ * @get_val: Callback to convert P state to actual MSR write value
+ * @get_vid: Callback to get VID data for Atom platforms
+ * @get_target_pstate: Callback to a function to calculate next P state to use
+ *
+ * Core and Atom CPU models have different way to get P State limits. This
+ * structure is used to store those callbacks.
+ */
struct pstate_funcs {
int (*get_max)(void);
int (*get_max_physical)(void);
@@ -139,6 +241,11 @@ struct pstate_funcs {
int32_t (*get_target_pstate)(struct cpudata *);
};
+/**
+ * struct cpu_defaults- Per CPU model default config data
+ * @pid_policy: PID config data
+ * @funcs: Callback function data
+ */
struct cpu_defaults {
struct pstate_adjust_policy pid_policy;
struct pstate_funcs funcs;
@@ -151,6 +258,34 @@ static struct pstate_adjust_policy pid_params;
static struct pstate_funcs pstate_funcs;
static int hwp_active;
+
+/**
+ * struct perf_limits - Store user and policy limits
+ * @no_turbo: User requested turbo state from intel_pstate sysfs
+ * @turbo_disabled: Platform turbo status either from msr
+ * MSR_IA32_MISC_ENABLE or when maximum available pstate
+ * matches the maximum turbo pstate
+ * @max_perf_pct: Effective maximum performance limit in percentage, this
+ * is minimum of either limits enforced by cpufreq policy
+ * or limits from user set limits via intel_pstate sysfs
+ * @min_perf_pct: Effective minimum performance limit in percentage, this
+ * is maximum of either limits enforced by cpufreq policy
+ * or limits from user set limits via intel_pstate sysfs
+ * @max_perf: This is a scaled value between 0 to 255 for max_perf_pct
+ * This value is used to limit max pstate
+ * @min_perf: This is a scaled value between 0 to 255 for min_perf_pct
+ * This value is used to limit min pstate
+ * @max_policy_pct: The maximum performance in percentage enforced by
+ * cpufreq setpolicy interface
+ * @max_sysfs_pct: The maximum performance in percentage enforced by
+ * intel pstate sysfs interface
+ * @min_policy_pct: The minimum performance in percentage enforced by
+ * cpufreq setpolicy interface
+ * @min_sysfs_pct: The minimum performance in percentage enforced by
+ * intel pstate sysfs interface
+ *
+ * Storage for user and policy defined limits.
+ */
struct perf_limits {
int no_turbo;
int turbo_disabled;
No code change. Only added kernel doc style comments for structures. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> --- drivers/cpufreq/intel_pstate.c | 135 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 135 insertions(+)