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Diffstat (limited to 'arch/arm/mach-tegra/cpu-tegra.c')
-rw-r--r--arch/arm/mach-tegra/cpu-tegra.c100
1 files changed, 84 insertions, 16 deletions
diff --git a/arch/arm/mach-tegra/cpu-tegra.c b/arch/arm/mach-tegra/cpu-tegra.c
index fea5719c7072..0e1016a827ac 100644
--- a/arch/arm/mach-tegra/cpu-tegra.c
+++ b/arch/arm/mach-tegra/cpu-tegra.c
@@ -28,6 +28,7 @@
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/suspend.h>
#include <asm/system.h>
@@ -36,21 +37,25 @@
/* Frequency table index must be sequential starting at 0 */
static struct cpufreq_frequency_table freq_table[] = {
- { 0, 312000 },
- { 1, 456000 },
- { 2, 608000 },
- { 3, 760000 },
- { 4, 816000 },
- { 5, 912000 },
- { 6, 1000000 },
- { 7, CPUFREQ_TABLE_END },
+ { 0, 216000 },
+ { 1, 312000 },
+ { 2, 456000 },
+ { 3, 608000 },
+ { 4, 760000 },
+ { 5, 816000 },
+ { 6, 912000 },
+ { 7, 1000000 },
+ { 8, CPUFREQ_TABLE_END },
};
#define NUM_CPUS 2
static struct clk *cpu_clk;
+static struct clk *emc_clk;
static unsigned long target_cpu_speed[NUM_CPUS];
+static DEFINE_MUTEX(tegra_cpu_lock);
+static bool is_suspended;
int tegra_verify_speed(struct cpufreq_policy *policy)
{
@@ -68,22 +73,28 @@ unsigned int tegra_getspeed(unsigned int cpu)
return rate;
}
-static int tegra_update_cpu_speed(void)
+static int tegra_update_cpu_speed(unsigned long rate)
{
- int i;
- unsigned long rate = 0;
int ret = 0;
struct cpufreq_freqs freqs;
- for_each_online_cpu(i)
- rate = max(rate, target_cpu_speed[i]);
-
freqs.old = tegra_getspeed(0);
freqs.new = rate;
if (freqs.old == freqs.new)
return ret;
+ /*
+ * Vote on memory bus frequency based on cpu frequency
+ * This sets the minimum frequency, display or avp may request higher
+ */
+ if (rate >= 816000)
+ clk_set_rate(emc_clk, 600000000); /* cpu 816 MHz, emc max */
+ else if (rate >= 456000)
+ clk_set_rate(emc_clk, 300000000); /* cpu 456 MHz, emc 150Mhz */
+ else
+ clk_set_rate(emc_clk, 100000000); /* emc 50Mhz */
+
for_each_online_cpu(freqs.cpu)
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
@@ -92,7 +103,7 @@ static int tegra_update_cpu_speed(void)
freqs.old, freqs.new);
#endif
- ret = clk_set_rate_cansleep(cpu_clk, freqs.new * 1000);
+ ret = clk_set_rate(cpu_clk, freqs.new * 1000);
if (ret) {
pr_err("cpu-tegra: Failed to set cpu frequency to %d kHz\n",
freqs.new);
@@ -105,12 +116,30 @@ static int tegra_update_cpu_speed(void)
return 0;
}
+static unsigned long tegra_cpu_highest_speed(void)
+{
+ unsigned long rate = 0;
+ int i;
+
+ for_each_online_cpu(i)
+ rate = max(rate, target_cpu_speed[i]);
+ return rate;
+}
+
static int tegra_target(struct cpufreq_policy *policy,
unsigned int target_freq,
unsigned int relation)
{
int idx;
unsigned int freq;
+ int ret = 0;
+
+ mutex_lock(&tegra_cpu_lock);
+
+ if (is_suspended) {
+ ret = -EBUSY;
+ goto out;
+ }
cpufreq_frequency_table_target(policy, freq_table, target_freq,
relation, &idx);
@@ -119,9 +148,34 @@ static int tegra_target(struct cpufreq_policy *policy,
target_cpu_speed[policy->cpu] = freq;
- return tegra_update_cpu_speed();
+ ret = tegra_update_cpu_speed(tegra_cpu_highest_speed());
+
+out:
+ mutex_unlock(&tegra_cpu_lock);
+ return ret;
}
+static int tegra_pm_notify(struct notifier_block *nb, unsigned long event,
+ void *dummy)
+{
+ mutex_lock(&tegra_cpu_lock);
+ if (event == PM_SUSPEND_PREPARE) {
+ is_suspended = true;
+ pr_info("Tegra cpufreq suspend: setting frequency to %d kHz\n",
+ freq_table[0].frequency);
+ tegra_update_cpu_speed(freq_table[0].frequency);
+ } else if (event == PM_POST_SUSPEND) {
+ is_suspended = false;
+ }
+ mutex_unlock(&tegra_cpu_lock);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block tegra_cpu_pm_notifier = {
+ .notifier_call = tegra_pm_notify,
+};
+
static int tegra_cpu_init(struct cpufreq_policy *policy)
{
if (policy->cpu >= NUM_CPUS)
@@ -131,6 +185,15 @@ static int tegra_cpu_init(struct cpufreq_policy *policy)
if (IS_ERR(cpu_clk))
return PTR_ERR(cpu_clk);
+ emc_clk = clk_get_sys("cpu", "emc");
+ if (IS_ERR(emc_clk)) {
+ clk_put(cpu_clk);
+ return PTR_ERR(emc_clk);
+ }
+
+ clk_enable(emc_clk);
+ clk_enable(cpu_clk);
+
cpufreq_frequency_table_cpuinfo(policy, freq_table);
cpufreq_frequency_table_get_attr(freq_table, policy->cpu);
policy->cur = tegra_getspeed(policy->cpu);
@@ -142,12 +205,17 @@ static int tegra_cpu_init(struct cpufreq_policy *policy)
policy->shared_type = CPUFREQ_SHARED_TYPE_ALL;
cpumask_copy(policy->related_cpus, cpu_possible_mask);
+ if (policy->cpu == 0)
+ register_pm_notifier(&tegra_cpu_pm_notifier);
+
return 0;
}
static int tegra_cpu_exit(struct cpufreq_policy *policy)
{
cpufreq_frequency_table_cpuinfo(policy, freq_table);
+ clk_disable(emc_clk);
+ clk_put(emc_clk);
clk_put(cpu_clk);
return 0;
}