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From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Linux PM <linux-pm@vger.kernel.org>
Cc: LKML <linux-kernel@vger.kernel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Subject: [PATCH 02/14] cpufreq: intel_pstate: Drop pointless initialization of PID parameters
Date: Sun, 12 Mar 2017 18:13:57 +0100	[thread overview]
Message-ID: <4421678.SbyKC18OPh@aspire.rjw.lan> (raw)
In-Reply-To: <5656785.7SEhxaGEOz@aspire.rjw.lan>

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The P-state selection algorithm used by intel_pstate for Atom
processors is not based on the PID controller and the initialization
of PID parametrs for those processors is pointless and confusing, so
drop it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/cpufreq/intel_pstate.c |   28 ++--------------------------
 1 file changed, 2 insertions(+), 26 deletions(-)

Index: linux-pm/drivers/cpufreq/intel_pstate.c
===================================================================
--- linux-pm.orig/drivers/cpufreq/intel_pstate.c
+++ linux-pm/drivers/cpufreq/intel_pstate.c
@@ -1592,14 +1592,6 @@ static struct cpu_defaults core_params =
 };
 
 static const struct cpu_defaults silvermont_params = {
-	.pid_policy = {
-		.sample_rate_ms = 10,
-		.deadband = 0,
-		.setpoint = 60,
-		.p_gain_pct = 14,
-		.d_gain_pct = 0,
-		.i_gain_pct = 4,
-	},
 	.funcs = {
 		.get_max = atom_get_max_pstate,
 		.get_max_physical = atom_get_max_pstate,
@@ -1613,14 +1605,6 @@ static const struct cpu_defaults silverm
 };
 
 static const struct cpu_defaults airmont_params = {
-	.pid_policy = {
-		.sample_rate_ms = 10,
-		.deadband = 0,
-		.setpoint = 60,
-		.p_gain_pct = 14,
-		.d_gain_pct = 0,
-		.i_gain_pct = 4,
-	},
 	.funcs = {
 		.get_max = atom_get_max_pstate,
 		.get_max_physical = atom_get_max_pstate,
@@ -1654,14 +1638,6 @@ static const struct cpu_defaults knl_par
 };
 
 static const struct cpu_defaults bxt_params = {
-	.pid_policy = {
-		.sample_rate_ms = 10,
-		.deadband = 0,
-		.setpoint = 60,
-		.p_gain_pct = 14,
-		.d_gain_pct = 0,
-		.i_gain_pct = 4,
-	},
 	.funcs = {
 		.get_max = core_get_max_pstate,
 		.get_max_physical = core_get_max_pstate_physical,
@@ -2721,9 +2697,9 @@ static int __init intel_pstate_init(void
 		return -ENODEV;
 
 	cpu_def = (struct cpu_defaults *)id->driver_data;
-
-	copy_pid_params(&cpu_def->pid_policy);
 	copy_cpu_funcs(&cpu_def->funcs);
+	if (pstate_funcs.get_target_pstate == get_target_pstate_use_performance)
+		copy_pid_params(&cpu_def->pid_policy);
 
 	if (intel_pstate_msrs_not_valid())
 		return -ENODEV;

  parent reply	other threads:[~2017-03-12 17:33 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-12 17:11 [PATCH 00/14] cpufreq: intel_pstate: Fixes, cleanups and optimizations Rafael J. Wysocki
2017-03-12 17:12 ` [PATCH 01/14] cpufreq: intel_pstate: Update pid_params.sample_rate_ns in pid_param_set() Rafael J. Wysocki
2017-03-13  4:00   ` Viresh Kumar
2017-03-12 17:13 ` Rafael J. Wysocki [this message]
2017-03-12 17:14 ` [PATCH 03/14] cpufreq: intel_pstate: Initialize pid_params statically Rafael J. Wysocki
2017-03-12 17:15 ` [PATCH 04/14] cpufreq: intel_pstate: Fold intel_pstate_reset_all_pid() into the caller Rafael J. Wysocki
2017-03-12 17:16 ` [PATCH 05/14] cpufreq: intel_pstate: Clean up intel_pstate_busy_pid_reset() Rafael J. Wysocki
2017-03-12 17:17 ` [PATCH 06/14] cpufreq: intel_pstate: Set HWP sampling interval once Rafael J. Wysocki
2017-03-12 17:18 ` [PATCH 07/14] cpufreq: intel_pstate: Skip unnecessary PID resets on init Rafael J. Wysocki
2017-03-12 17:19 ` [PATCH 08/14] cpufreq: intel_pstate: Drop driver_registered variable Rafael J. Wysocki
2017-03-12 17:20 ` [PATCH 09/14] cpufreq: intel_pstate: Modify check in intel_pstate_update_status() Rafael J. Wysocki
2017-03-12 17:21 ` [PATCH 10/14] cpufreq: intel_pstate: Use different utilization update callbacks Rafael J. Wysocki
2017-03-12 17:22 ` [PATCH 11/14] cpufreq: intel_pstate: Add update_util callback to pstate_funcs Rafael J. Wysocki
2017-03-12 17:23 ` [PATCH 12/14] cpufreq: intel_pstate: Move cpu_defaults definitions Rafael J. Wysocki
2017-03-12 17:23 ` [PATCH 13/14] cpufreq: intel_pstate: Drop struct cpu_defaults Rafael J. Wysocki
2017-03-12 17:26 ` [PATCH 14/14] cpufreq: intel_pstate: Introduce pid_in_use() Rafael J. Wysocki
2017-03-14 16:06 ` [PATCH 07/14] cpufreq: intel_pstate: Skip unnecessary PID resets on init Doug Smythies
2017-03-14 16:40   ` Rafael J. Wysocki
2017-03-14 16:07 ` [PATCH 10/14] cpufreq: intel_pstate: Use different utilization update callbacks Doug Smythies
2017-03-14 16:41   ` Rafael J. Wysocki

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