Tegra's driver got updated a bit (00917dd cpufreq: Tegra: implement intermediate frequency callbacks) and implements new 'intermediate freq' infrastructure of core. Above commit updated comments about when to call clk_prepare_enable(pll_x_clk) and Doug wasn't satisfied with those comments and said this:
The "Though when target-freq is intermediate freq, we don't need to take this reference." makes me think that this function is actually called when target-freq is intermediate freq. I don't think it is, right?
For better clarity just make that comment more explicit about when we call tegra_target_intermediate(). Wasn't sure if we actually need a commit for this, but anyway lets other decide if its worth enough :)
Reported-by: Doug Anderson dianders@chromium.org Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- drivers/cpufreq/tegra-cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/cpufreq/tegra-cpufreq.c b/drivers/cpufreq/tegra-cpufreq.c index a5fbc0a..48bc89b 100644 --- a/drivers/cpufreq/tegra-cpufreq.c +++ b/drivers/cpufreq/tegra-cpufreq.c @@ -73,7 +73,7 @@ static int tegra_target_intermediate(struct cpufreq_policy *policy, * off when we move the cpu off of it as enabling it again while we * switch to it from tegra_target() would take additional time. Though * when target-freq is intermediate freq, we don't need to take this - * reference. + * reference and so this routine isn't called at all. */ clk_prepare_enable(pll_x_clk);
Viresh,
On Thu, Jun 5, 2014 at 9:38 PM, Viresh Kumar viresh.kumar@linaro.org wrote:
Tegra's driver got updated a bit (00917dd cpufreq: Tegra: implement intermediate frequency callbacks) and implements new 'intermediate freq' infrastructure of core. Above commit updated comments about when to call clk_prepare_enable(pll_x_clk) and Doug wasn't satisfied with those comments and said this:
The "Though when target-freq is intermediate freq, we don't need to take this reference." makes me think that this function is actually called when target-freq is intermediate freq. I don't think it is, right?
For better clarity just make that comment more explicit about when we call tegra_target_intermediate(). Wasn't sure if we actually need a commit for this, but anyway lets other decide if its worth enough :)
Reported-by: Doug Anderson dianders@chromium.org Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
drivers/cpufreq/tegra-cpufreq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/cpufreq/tegra-cpufreq.c b/drivers/cpufreq/tegra-cpufreq.c index a5fbc0a..48bc89b 100644 --- a/drivers/cpufreq/tegra-cpufreq.c +++ b/drivers/cpufreq/tegra-cpufreq.c @@ -73,7 +73,7 @@ static int tegra_target_intermediate(struct cpufreq_policy *policy, * off when we move the cpu off of it as enabling it again while we * switch to it from tegra_target() would take additional time. Though * when target-freq is intermediate freq, we don't need to take this
* reference.
* reference and so this routine isn't called at all.
I'm OK either way, so up to others.
Reviewed-by: Doug Anderson dianders@chromium.org
On 06/05/2014 10:38 PM, Viresh Kumar wrote:
Tegra's driver got updated a bit (00917dd cpufreq: Tegra: implement intermediate frequency callbacks) and implements new 'intermediate freq' infrastructure of core. Above commit updated comments about when to call clk_prepare_enable(pll_x_clk) and Doug wasn't satisfied with those comments and said this:
The "Though when target-freq is intermediate freq, we don't need to take this reference." makes me think that this function is actually called when target-freq is intermediate freq. I don't think it is, right?
For better clarity just make that comment more explicit about when we call tegra_target_intermediate(). Wasn't sure if we actually need a commit for this, but anyway lets other decide if its worth enough :)
diff --git a/drivers/cpufreq/tegra-cpufreq.c b/drivers/cpufreq/tegra-cpufreq.c index a5fbc0a..48bc89b 100644 --- a/drivers/cpufreq/tegra-cpufreq.c +++ b/drivers/cpufreq/tegra-cpufreq.c @@ -73,7 +73,7 @@ static int tegra_target_intermediate(struct cpufreq_policy *policy, * off when we move the cpu off of it as enabling it again while we * switch to it from tegra_target() would take additional time. Though * when target-freq is intermediate freq, we don't need to take this
* reference.
*/ clk_prepare_enable(pll_x_clk);* reference and so this routine isn't called at all.
I would remove the word "so" in the added line; the function is not called because we don't need to use an intermediate frequency, not because we don't need to take a reference to pll_x. With that change,
Reviewed-by: Stephen Warren swarren@nvidia.com
Tegra's driver got updated a bit (00917dd cpufreq: Tegra: implement intermediate frequency callbacks) and implements new 'intermediate freq' infrastructure of core. Above commit updated comments about when to call clk_prepare_enable(pll_x_clk) and Doug wasn't satisfied with those comments and said this:
The "Though when target-freq is intermediate freq, we don't need to take this reference." makes me think that this function is actually called when target-freq is intermediate freq. I don't think it is, right?
For better clarity just make that comment more explicit about when we call tegra_target_intermediate().
Reviewed-by: Stephen Warren swarren@nvidia.com Reported-and-reviewed-by: Doug Anderson dianders@chromium.org Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- Resend: Improved comment as suggested by Stephen.
drivers/cpufreq/tegra-cpufreq.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/drivers/cpufreq/tegra-cpufreq.c b/drivers/cpufreq/tegra-cpufreq.c index a5fbc0a..8084c7f 100644 --- a/drivers/cpufreq/tegra-cpufreq.c +++ b/drivers/cpufreq/tegra-cpufreq.c @@ -71,9 +71,12 @@ static int tegra_target_intermediate(struct cpufreq_policy *policy, /* * Take an extra reference to the main pll so it doesn't turn * off when we move the cpu off of it as enabling it again while we - * switch to it from tegra_target() would take additional time. Though - * when target-freq is intermediate freq, we don't need to take this - * reference. + * switch to it from tegra_target() would take additional time. + * + * When target-freq is equal to intermediate freq we don't need to + * switch to an intermediate freq and so this routine isn't called. + * Also, we wouldn't be using pll_x anymore and must not take extra + * reference to it, as it can be disabled now to save some power. */ clk_prepare_enable(pll_x_clk);
On Tuesday, June 10, 2014 10:27:12 AM Viresh Kumar wrote:
Tegra's driver got updated a bit (00917dd cpufreq: Tegra: implement intermediate frequency callbacks) and implements new 'intermediate freq' infrastructure of core. Above commit updated comments about when to call clk_prepare_enable(pll_x_clk) and Doug wasn't satisfied with those comments and said this:
The "Though when target-freq is intermediate freq, we don't need to take this reference." makes me think that this function is actually called when target-freq is intermediate freq. I don't think it is, right?
For better clarity just make that comment more explicit about when we call tegra_target_intermediate().
Reviewed-by: Stephen Warren swarren@nvidia.com Reported-and-reviewed-by: Doug Anderson dianders@chromium.org Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Resend: Improved comment as suggested by Stephen.
Applied to bleeding-edge, thanks!
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