[PATCH v3 3/3] cpufreq: Add a generic cpufreq-cpu0 driver
Shawn Guo
shawn.guo at linaro.org
Thu Sep 6 03:29:38 EDT 2012
On Wed, Sep 05, 2012 at 10:18:50PM +0200, Rafael J. Wysocki wrote:
> On Wednesday, September 05, 2012, Shawn Guo wrote:
> > On Wed, Sep 05, 2012 at 03:38:12PM +0200, Rafael J. Wysocki wrote:
> > > Well, what about actually avoiding the code duplication? That is,
> > > can you make OMAP be a user of your new core function and drop the
> > > OMAP-specific one, perhaps?
> > >
> > I would expect that the driver will replace the omap-cpufreq driver
> > completely at some point, where omap becomes a DT only platform.
>
> That's fine, but why do we need two almost identical functions to start with?
>
Probably because it does not worth the churn considering that any
particular cpufreq driver having an identical .set_target as this
generic one should eventually be replaced by this driver completely,
IMO.
But anyway, it could be another patch which may need more discussion,
so I just submitted the v4 with leaving this particular comment to be
addressed in another patch.
I'm unsure this is what you are ordering. But here is what I come up
with to address your comment. Please let me know if this is exactly
what you are asking for, or you expect something different.
Regards,
Shawn
8<---
drivers/cpufreq/Kconfig | 4 ++
drivers/cpufreq/Kconfig.arm | 1 +
drivers/cpufreq/Makefile | 1 +
drivers/cpufreq/cpufreq-cpu0.c | 94 +++++-----------------------------
drivers/cpufreq/cpufreq.h | 31 +++++++++++
drivers/cpufreq/cpufreq_target.c | 99 +++++++++++++++++++++++++++++++++++
drivers/cpufreq/omap-cpufreq.c | 105 +++++---------------------------------
7 files changed, 163 insertions(+), 172 deletions(-)
create mode 100644 drivers/cpufreq/cpufreq.h
create mode 100644 drivers/cpufreq/cpufreq_target.c
diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index ea512f4..206eec9 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -20,6 +20,9 @@ if CPU_FREQ
config CPU_FREQ_TABLE
tristate
+config CPU_FREQ_TARGET
+ tristate
+
config CPU_FREQ_STAT
tristate "CPU frequency translation statistics"
select CPU_FREQ_TABLE
@@ -183,6 +186,7 @@ config GENERIC_CPUFREQ_CPU0
bool "Generic CPU0 cpufreq driver"
depends on HAVE_CLK && REGULATOR && PM_OPP && OF
select CPU_FREQ_TABLE
+ select CPU_FREQ_TARGET
help
This adds a generic cpufreq driver for CPU0 frequency management.
It supports both uniprocessor (UP) and symmetric multiprocessor (SMP)
diff --git a/drivers/cpufreq/Kconfig.arm b/drivers/cpufreq/Kconfig.arm
index 5961e64..60d81d0 100644
--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -7,6 +7,7 @@ config ARM_OMAP2PLUS_CPUFREQ
depends on ARCH_OMAP2PLUS
default ARCH_OMAP2PLUS
select CPU_FREQ_TABLE
+ select CPU_FREQ_TARGET
config ARM_S3C2416_CPUFREQ
bool "S3C2416 CPU Frequency scaling support"
diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile
index a378ed2..f7d19d1 100644
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -12,6 +12,7 @@ obj-$(CONFIG_CPU_FREQ_GOV_CONSERVATIVE) += cpufreq_conservative.o
# CPUfreq cross-arch helpers
obj-$(CONFIG_CPU_FREQ_TABLE) += freq_table.o
+obj-$(CONFIG_CPU_FREQ_TARGET) += cpufreq_target.o
obj-$(CONFIG_GENERIC_CPUFREQ_CPU0) += cpufreq-cpu0.o
diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-cpu0.c
index e915827..51096e8 100644
--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c
@@ -1,9 +1,6 @@
/*
* Copyright (C) 2012 Freescale Semiconductor, Inc.
*
- * The OPP code in function cpu0_set_target() is reused from
- * drivers/cpufreq/omap-cpufreq.c
- *
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
@@ -20,6 +17,7 @@
#include <linux/opp.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
+#include "cpufreq.h"
static unsigned int transition_latency;
static unsigned int voltage_tolerance; /* in percentage */
@@ -42,84 +40,18 @@ static unsigned int cpu0_get_speed(unsigned int cpu)
static int cpu0_set_target(struct cpufreq_policy *policy,
unsigned int target_freq, unsigned int relation)
{
- struct cpufreq_freqs freqs;
- struct opp *opp;
- unsigned long freq_Hz, volt = 0, volt_old = 0, tol = 0;
- unsigned int index, cpu;
- int ret;
-
- ret = cpufreq_frequency_table_target(policy, freq_table, target_freq,
- relation, &index);
- if (ret) {
- pr_err("failed to match target freqency %d: %d\n",
- target_freq, ret);
- return ret;
- }
-
- freq_Hz = clk_round_rate(cpu_clk, freq_table[index].frequency * 1000);
- if (freq_Hz < 0)
- freq_Hz = freq_table[index].frequency * 1000;
- freqs.new = freq_Hz / 1000;
- freqs.old = clk_get_rate(cpu_clk) / 1000;
-
- if (freqs.old == freqs.new)
- return 0;
-
- for_each_online_cpu(cpu) {
- freqs.cpu = cpu;
- cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
- }
-
- if (cpu_reg) {
- opp = opp_find_freq_ceil(cpu_dev, &freq_Hz);
- if (IS_ERR(opp)) {
- pr_err("failed to find OPP for %ld\n", freq_Hz);
- return PTR_ERR(opp);
- }
- volt = opp_get_voltage(opp);
- tol = volt * voltage_tolerance / 100;
- volt_old = regulator_get_voltage(cpu_reg);
- }
-
- pr_debug("%u MHz, %ld mV --> %u MHz, %ld mV\n",
- freqs.old / 1000, volt_old ? volt_old / 1000 : -1,
- freqs.new / 1000, volt ? volt / 1000 : -1);
-
- /* scaling up? scale voltage before frequency */
- if (cpu_reg && freqs.new > freqs.old) {
- ret = regulator_set_voltage_tol(cpu_reg, volt, tol);
- if (ret) {
- pr_err("failed to scale voltage up: %d\n", ret);
- freqs.new = freqs.old;
- return ret;
- }
- }
-
- ret = clk_set_rate(cpu_clk, freqs.new * 1000);
- if (ret) {
- pr_err("failed to set clock rate: %d\n", ret);
- if (cpu_reg)
- regulator_set_voltage_tol(cpu_reg, volt_old, tol);
- return ret;
- }
-
- /* scaling down? scale voltage after frequency */
- if (cpu_reg && freqs.new < freqs.old) {
- ret = regulator_set_voltage_tol(cpu_reg, volt, tol);
- if (ret) {
- pr_err("failed to scale voltage down: %d\n", ret);
- clk_set_rate(cpu_clk, freqs.old * 1000);
- freqs.new = freqs.old;
- return ret;
- }
- }
-
- for_each_online_cpu(cpu) {
- freqs.cpu = cpu;
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
- }
-
- return 0;
+ struct cpufreq_target_data data;
+
+ data.dev = cpu_dev;
+ data.clk = cpu_clk;
+ data.reg = cpu_reg;
+ data.tol = voltage_tolerance;
+ data.freq_table = freq_table;
+ data.policy = policy;
+ data.target_freq = target_freq;
+ data.relation = relation;
+
+ return cpufreq_set_target(&data);
}
static int cpu0_cpufreq_init(struct cpufreq_policy *policy)
diff --git a/drivers/cpufreq/cpufreq.h b/drivers/cpufreq/cpufreq.h
new file mode 100644
index 0000000..ae380b3
--- /dev/null
+++ b/drivers/cpufreq/cpufreq.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef _DRIVERS_CPUFREQ_H
+#define _DRIVERS_CPUFREQ_H
+
+struct device;
+struct clk;
+struct regulator;
+struct cpufreq_frequency_table;
+struct cpufreq_policy;
+
+struct cpufreq_target_data {
+ struct device *dev;
+ struct clk *clk;
+ struct regulator *reg;
+ unsigned int tol;
+ struct cpufreq_frequency_table *freq_table;
+ struct cpufreq_policy *policy;
+ unsigned int target_freq;
+ unsigned int relation;
+};
+
+int cpufreq_set_target(struct cpufreq_target_data *data);
+
+#endif /* _DRIVERS_CPUFREQ_H */
diff --git a/drivers/cpufreq/cpufreq_target.c b/drivers/cpufreq/cpufreq_target.c
new file mode 100644
index 0000000..02a5584
--- /dev/null
+++ b/drivers/cpufreq/cpufreq_target.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2012 Freescale Semiconductor, Inc.
+ *
+ * Based on function omap_target() from drivers/cpufreq/omap-cpufreq.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
+#include <linux/module.h>
+#include <linux/opp.h>
+#include <linux/regulator/consumer.h>
+#include "cpufreq.h"
+
+int cpufreq_set_target(struct cpufreq_target_data *d)
+{
+ struct cpufreq_freqs freqs;
+ struct opp *opp;
+ unsigned long freq_Hz, volt = 0, volt_old = 0, tol = 0;
+ unsigned int index, cpu;
+ int ret;
+
+ ret = cpufreq_frequency_table_target(d->policy, d->freq_table,
+ d->target_freq, d->relation,
+ &index);
+ if (ret) {
+ pr_err("failed to match target freqency %d: %d\n",
+ d->target_freq, ret);
+ return ret;
+ }
+
+ freq_Hz = clk_round_rate(d->clk, d->freq_table[index].frequency * 1000);
+ if (freq_Hz < 0)
+ freq_Hz = d->freq_table[index].frequency * 1000;
+ freqs.new = freq_Hz / 1000;
+ freqs.old = clk_get_rate(d->clk) / 1000;
+
+ if (freqs.old == freqs.new)
+ return 0;
+
+ for_each_online_cpu(cpu) {
+ freqs.cpu = cpu;
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+ }
+
+ if (d->reg) {
+ opp = opp_find_freq_ceil(d->dev, &freq_Hz);
+ if (IS_ERR(opp)) {
+ pr_err("failed to find OPP for %ld\n", freq_Hz);
+ return PTR_ERR(opp);
+ }
+ volt = opp_get_voltage(opp);
+ tol = volt * d->tol / 100;
+ volt_old = regulator_get_voltage(d->reg);
+ }
+
+ pr_debug("%u MHz, %ld mV --> %u MHz, %ld mV\n",
+ freqs.old / 1000, volt_old ? volt_old / 1000 : -1,
+ freqs.new / 1000, volt ? volt / 1000 : -1);
+
+ /* scaling up? scale voltage before frequency */
+ if (d->reg && freqs.new > freqs.old) {
+ ret = regulator_set_voltage_tol(d->reg, volt, tol);
+ if (ret) {
+ pr_err("failed to scale voltage up: %d\n", ret);
+ freqs.new = freqs.old;
+ return ret;
+ }
+ }
+
+ ret = clk_set_rate(d->clk, freqs.new * 1000);
+ if (ret) {
+ pr_err("failed to set clock rate: %d\n", ret);
+ if (d->reg)
+ regulator_set_voltage_tol(d->reg, volt_old, tol);
+ return ret;
+ }
+
+ /* scaling down? scale voltage after frequency */
+ if (d->reg && freqs.new < freqs.old) {
+ ret = regulator_set_voltage_tol(d->reg, volt, tol);
+ if (ret) {
+ pr_err("failed to scale voltage down: %d\n", ret);
+ clk_set_rate(d->clk, freqs.old * 1000);
+ freqs.new = freqs.old;
+ return ret;
+ }
+ }
+
+ for_each_online_cpu(cpu) {
+ freqs.cpu = cpu;
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_set_target);
diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c
index 83a78ad..0772df5 100644
--- a/drivers/cpufreq/omap-cpufreq.c
+++ b/drivers/cpufreq/omap-cpufreq.c
@@ -37,6 +37,8 @@
#include <mach/hardware.h>
+#include "cpufreq.h"
+
/* OPP tolerance in percentage */
#define OPP_TOLERANCE 4
@@ -69,97 +71,18 @@ static int omap_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
- unsigned int i;
- int r, ret = 0;
- struct cpufreq_freqs freqs;
- struct opp *opp;
- unsigned long freq, volt = 0, volt_old = 0, tol = 0;
-
- if (!freq_table) {
- dev_err(mpu_dev, "%s: cpu%d: no freq table!\n", __func__,
- policy->cpu);
- return -EINVAL;
- }
-
- ret = cpufreq_frequency_table_target(policy, freq_table, target_freq,
- relation, &i);
- if (ret) {
- dev_dbg(mpu_dev, "%s: cpu%d: no freq match for %d(ret=%d)\n",
- __func__, policy->cpu, target_freq, ret);
- return ret;
- }
- freqs.new = freq_table[i].frequency;
- if (!freqs.new) {
- dev_err(mpu_dev, "%s: cpu%d: no match for freq %d\n", __func__,
- policy->cpu, target_freq);
- return -EINVAL;
- }
-
- freqs.old = omap_getspeed(policy->cpu);
- freqs.cpu = policy->cpu;
-
- if (freqs.old == freqs.new && policy->cur == freqs.new)
- return ret;
-
- /* notifiers */
- for_each_cpu(i, policy->cpus) {
- freqs.cpu = i;
- cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
- }
-
- freq = freqs.new * 1000;
-
- if (mpu_reg) {
- opp = opp_find_freq_ceil(mpu_dev, &freq);
- if (IS_ERR(opp)) {
- dev_err(mpu_dev, "%s: unable to find MPU OPP for %d\n",
- __func__, freqs.new);
- return -EINVAL;
- }
- volt = opp_get_voltage(opp);
- tol = volt * OPP_TOLERANCE / 100;
- volt_old = regulator_get_voltage(mpu_reg);
- }
-
- dev_dbg(mpu_dev, "cpufreq-omap: %u MHz, %ld mV --> %u MHz, %ld mV\n",
- freqs.old / 1000, volt_old ? volt_old / 1000 : -1,
- freqs.new / 1000, volt ? volt / 1000 : -1);
-
- /* scaling up? scale voltage before frequency */
- if (mpu_reg && (freqs.new > freqs.old)) {
- r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
- if (r < 0) {
- dev_warn(mpu_dev, "%s: unable to scale voltage up.\n",
- __func__);
- freqs.new = freqs.old;
- goto done;
- }
- }
-
- ret = clk_set_rate(mpu_clk, freqs.new * 1000);
-
- /* scaling down? scale voltage after frequency */
- if (mpu_reg && (freqs.new < freqs.old)) {
- r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
- if (r < 0) {
- dev_warn(mpu_dev, "%s: unable to scale voltage down.\n",
- __func__);
- ret = clk_set_rate(mpu_clk, freqs.old * 1000);
- freqs.new = freqs.old;
- goto done;
- }
- }
-
- freqs.new = omap_getspeed(policy->cpu);
-
-done:
- /* notifiers */
- for_each_cpu(i, policy->cpus) {
- freqs.cpu = i;
- cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
- }
-
- return ret;
+ struct cpufreq_target_data data;
+
+ data.dev = mpu_dev;
+ data.clk = mpu_clk;
+ data.reg = mpu_reg;
+ data.tol = OPP_TOLERANCE;
+ data.freq_table = freq_table;
+ data.policy = policy;
+ data.target_freq = target_freq;
+ data.relation = relation;
+
+ return cpufreq_set_target(&data);
}
static inline void freq_table_free(void)
--
1.7.5.4
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