Use the regulator framework to get the voltage regulator associated
with the MPU voltage domain and use it to scale voltage along with
frequency.
While here, CONFIG_CPU_FREQ_DEBUG doesn't exist anymore, so move
debug prints to use dev_dbg().
Special thanks to Afzal Mohammed for suggestions on more robust error
checking.
Cc: Afzal Mohammed <afzal@xxxxxx>
Signed-off-by: Kevin Hilman <khilman@xxxxxx>
---
drivers/cpufreq/omap-cpufreq.c | 68 +++++++++++++++++++++++++++++++++++++---
1 files changed, 63 insertions(+), 5 deletions(-)
diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c
index 5d04c57..9f5d636 100644
--- a/drivers/cpufreq/omap-cpufreq.c
+++ b/drivers/cpufreq/omap-cpufreq.c
@@ -25,6 +25,7 @@
#include <linux/opp.h>
#include <linux/cpu.h>
#include <linux/module.h>
+#include <linux/regulator/consumer.h>
#include <asm/system.h>
#include <asm/smp_plat.h>
@@ -52,6 +53,7 @@ static atomic_t freq_table_users = ATOMIC_INIT(0);
static struct clk *mpu_clk;
static char *mpu_clk_name;
static struct device *mpu_dev;
+static struct regulator *mpu_reg;
static int omap_verify_speed(struct cpufreq_policy *policy)
{
@@ -76,8 +78,10 @@ static int omap_target(struct cpufreq_policy *policy,
unsigned int relation)
{
unsigned int i;
- int ret = 0;
+ int r, ret = 0;
struct cpufreq_freqs freqs;
+ struct opp *opp;
+ unsigned long freq, volt = 0, volt_old = 0;
if (!freq_table) {
dev_err(mpu_dev, "%s: cpu%d: no freq table!\n", __func__,
@@ -111,13 +115,49 @@ static int omap_target(struct cpufreq_policy *policy,
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
}
-#ifdef CONFIG_CPU_FREQ_DEBUG
- pr_info("cpufreq-omap: transition: %u --> %u\n", freqs.old, freqs.new);
-#endif
+ 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);
+ 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, volt);
+ 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);
- freqs.new = omap_getspeed(policy->cpu);
+ /* scaling down? scale voltage after frequency */
+ if (mpu_reg && (freqs.new < freqs.old)) {
+ r = regulator_set_voltage(mpu_reg, volt, volt);
+ 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);
#ifdef CONFIG_SMP
/*
* Note that loops_per_jiffy is not updated on SMP systems in
@@ -144,6 +184,7 @@ static int omap_target(struct cpufreq_policy *policy,
freqs.new);
#endif
+done:
/* notifiers */
for_each_cpu(i, policy->cpus) {
freqs.cpu = i;
@@ -260,6 +301,23 @@ static int __init omap_cpufreq_init(void)
return -EINVAL;
}
+ mpu_reg = regulator_get(mpu_dev, "vcc");
+ if (IS_ERR(mpu_reg)) {
+ pr_warning("%s: unable to get MPU regulator\n", __func__);
+ mpu_reg = NULL;
+ } else {
+ /*
+ * Ensure physical regulator is present.
+ * (e.g. could be dummy regulator.)
+ */
+ if (regulator_get_voltage(mpu_reg) < 0) {
+ pr_warn("%s: physical regulator not present for MPU\n",
+ __func__);
+ regulator_put(mpu_reg);
+ mpu_reg = NULL;
+ }
+ }
+
return cpufreq_register_driver(&omap_driver);
}
--
1.7.9.1
--
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