From 8478f53946f01b8365a206ac58a2640e3e408fb2 Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Fri, 20 Nov 2015 18:47:56 -0500 Subject: cpufreq: intel_pstate: Fix limits->max_policy_pct rounding error I have a Intel (6,63) processor with a "marketing" frequency (from /proc/cpuinfo) of 2100MHz, and a max turbo frequency of 2600MHz. I can execute cpupower frequency-set -g powersave --min 1200MHz --max 2100MHz and the max_freq_pct is set to 80. When adding load to the system I noticed that the cpu frequency only reached 2000MHZ and not 2100MHz as expected. This is because limits->max_policy_pct is calculated as 2100 * 100 /2600 = 80.7 and is rounded down to 80 when it should be rounded up to 81. This patch adds a DIV_ROUND_UP() which will return the correct value. Signed-off-by: Prarit Bhargava Acked-by: Srinivas Pandruvada Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers/cpufreq/intel_pstate.c') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 001a532e342e..eb75053f1371 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1108,7 +1108,8 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) limits = &powersave_limits; limits->min_policy_pct = (policy->min * 100) / policy->cpuinfo.max_freq; limits->min_policy_pct = clamp_t(int, limits->min_policy_pct, 0 , 100); - limits->max_policy_pct = (policy->max * 100) / policy->cpuinfo.max_freq; + limits->max_policy_pct = DIV_ROUND_UP(policy->max * 100, + policy->cpuinfo.max_freq); limits->max_policy_pct = clamp_t(int, limits->max_policy_pct, 0 , 100); /* Normalize user input to [min_policy_pct, max_policy_pct] */ -- cgit v1.2.3 From 785ee27881411bd971d5e37a7fd72a5063fc1237 Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Fri, 20 Nov 2015 18:47:57 -0500 Subject: cpufreq: intel_pstate: Fix limits->max_perf rounding error A rounding error was found in the calculation of limits->max_perf in intel_pstate_set_policy(), which is used to calculate the max and min pstate values in intel_pstate_get_min_max(). In that code, limits->max_perf is truncated to 2 hex digits such that, for example, 0x169 was incorrectly calculated to 0x16 instead of 0x17. This resulted in the pstate being set one level too low. This patch rounds the value of limits->max_perf up instead of down so that the correct max pstate can be reached. Signed-off-by: Prarit Bhargava Acked-by: Srinivas Pandruvada Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/cpufreq/intel_pstate.c') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index eb75053f1371..8ad1f958ffe4 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1121,6 +1121,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) limits->max_sysfs_pct); limits->max_perf_pct = max(limits->min_policy_pct, limits->max_perf_pct); + limits->max_perf = round_up(limits->max_perf, 8); /* Make sure min_perf_pct <= max_perf_pct */ limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct); -- cgit v1.2.3 From 584ee3dcb1d6232857c1e38bb28d9f6bf0ec89f5 Mon Sep 17 00:00:00 2001 From: Alexandra Yates Date: Wed, 18 Nov 2015 14:58:40 -0800 Subject: intel_pstate: Fix "performance" mode behavior with HWP enabled If hardware-driven P-state selection (HWP) is enabled, the "performance" mode of intel_pstate should only allow the processor to use the highest-performance P-state available. That is not the case currently, so make it actually happen. Acked-by: Srinivas Pandruvada Signed-off-by: Alexandra Yates [ rjw: Subject and changelog ] Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/cpufreq/intel_pstate.c') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 8ad1f958ffe4..4d07cbd2b23c 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1101,6 +1101,8 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) policy->max >= policy->cpuinfo.max_freq) { pr_debug("intel_pstate: set performance\n"); limits = &performance_limits; + if (hwp_active) + intel_pstate_hwp_set(); return 0; } -- cgit v1.2.3 From 88b7b7c0c2ba2c1f2c589ee883050717fe91af22 Mon Sep 17 00:00:00 2001 From: Prarit Bhargava Date: Tue, 8 Dec 2015 13:44:59 -0500 Subject: cpufreq: intel_pstate: Minor cleanup for FRAC_BITS 785ee27 ("cpufreq: intel_pstate: Fix limits->max_perf rounding error") hardcodes the value of FRAC_BITS. This patch fixes that minor issue. Fixes: 785ee2788141 (cpufreq: intel_pstate: Fix limits->max_perf rounding error) Signed-off-by: Prarit Bhargava Acked-by: Viresh Kumar Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/cpufreq/intel_pstate.c') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 4d07cbd2b23c..98fb8821382d 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -1123,7 +1123,7 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) limits->max_sysfs_pct); limits->max_perf_pct = max(limits->min_policy_pct, limits->max_perf_pct); - limits->max_perf = round_up(limits->max_perf, 8); + limits->max_perf = round_up(limits->max_perf, FRAC_BITS); /* Make sure min_perf_pct <= max_perf_pct */ limits->min_perf_pct = min(limits->max_perf_pct, limits->min_perf_pct); -- cgit v1.2.3