diff mbox

[1/2] cpufreq: expose a cpufreq_quick_get_max routine

Message ID 1308939194-3568-1-git-send-email-jbarnes@virtuousgeek.org (mailing list archive)
State New, archived
Headers show

Commit Message

Jesse Barnes June 24, 2011, 6:13 p.m. UTC 
This allows drivers and other code to get the max reported CPU frequency.
Initial use is for scaling ring frequency with GPU frequency in the i915
driver.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
 drivers/cpufreq/cpufreq.c |   20 ++++++++++++++++++++
 include/linux/cpufreq.h   |    5 +++++
 2 files changed, 25 insertions(+), 0 deletions(-)

Comments

Chris Wilson June 27, 2011, 7:03 p.m. UTC | #1 
On Fri, 24 Jun 2011 11:13:13 -0700, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> This allows drivers and other code to get the max reported CPU frequency.
> Initial use is for scaling ring frequency with GPU frequency in the i915
> driver.

Note that there is a potential user of interface in
arch/x86/kvm/x86.c::kvm_timer_init().
-Chris
diff mbox

Patch

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 0a5bea9..987a165 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1199,6 +1199,26 @@  unsigned int cpufreq_quick_get(unsigned int cpu)
 }
 EXPORT_SYMBOL(cpufreq_quick_get);
 
+/**
+ * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU
+ * @cpu: CPU number
+ *
+ * Just return the max possible frequency for a given CPU.
+ */
+unsigned int cpufreq_quick_get_max(unsigned int cpu)
+{
+	struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+	unsigned int ret_freq = 0;
+
+	if (policy) {
+		ret_freq = policy->max;
+		cpufreq_cpu_put(policy);
+	}
+
+	return ret_freq;
+}
+EXPORT_SYMBOL(cpufreq_quick_get_max);
+
 
 static unsigned int __cpufreq_get(unsigned int cpu)
 {
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 11be48e..6216115 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -324,11 +324,16 @@  static inline unsigned int cpufreq_get(unsigned int cpu)
 /* query the last known CPU freq (in kHz). If zero, cpufreq couldn't detect it */
 #ifdef CONFIG_CPU_FREQ
 unsigned int cpufreq_quick_get(unsigned int cpu);
+unsigned int cpufreq_quick_get_max(unsigned int cpu);
 #else
 static inline unsigned int cpufreq_quick_get(unsigned int cpu)
 {
 	return 0;
 }
+static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
+{
+	return 0;
+}
 #endif