diff options
Diffstat (limited to 'target/linux/mvebu/patches-3.18/061-cpuidle-mvebu-Update-cpuidle-thresholds-for-Armada-X.patch')
| -rw-r--r-- | target/linux/mvebu/patches-3.18/061-cpuidle-mvebu-Update-cpuidle-thresholds-for-Armada-X.patch | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/target/linux/mvebu/patches-3.18/061-cpuidle-mvebu-Update-cpuidle-thresholds-for-Armada-X.patch b/target/linux/mvebu/patches-3.18/061-cpuidle-mvebu-Update-cpuidle-thresholds-for-Armada-X.patch new file mode 100644 index 0000000..bc0f1a6 --- /dev/null +++ b/target/linux/mvebu/patches-3.18/061-cpuidle-mvebu-Update-cpuidle-thresholds-for-Armada-X.patch @@ -0,0 +1,66 @@ +From ce6031c89a35cffd5a5992b08377b77f49a004b9 Mon Sep 17 00:00:00 2001 +From: Sebastien Rannou <mxs@sbrk.org> +Date: Fri, 13 Feb 2015 15:55:03 +0100 +Subject: [PATCH] cpuidle: mvebu: Update cpuidle thresholds for Armada XP SOCs + +Originally, the thresholds used in the cpuidle driver for Armada SOCs +were temporarily chosen, leaving room for improvements. + +This commit updates the thresholds for the Armada XP SOCs with values +that positively impact performances: + + without patch with patch vendor kernel + - iperf localhost (gbit/sec) ~3.7 ~6.4 ~5.4 + - ioping tmpfs (iops) ~163k ~206k ~179k + - ioping tmpfs (mib/s) ~636 ~805 ~699 + +The idle power consumption is negatively impacted (proportionally less +than the performance gain), and we are still performing better than +the vendor kernel here: + + without patch with patch vendor kernel + - power consumption idle (W) ~2.4 ~3.2 ~4.4 + - power consumption busy (W) ~8.6 ~8.3 ~8.6 + +There is still room for improvement regarding the value of these +thresholds, they were chosen to mimic the vendor kernel. + +This patch only impacts Armada XP SOCs and was tested on Online Labs +C1 boards. A similar approach can be taken to improve the performances +of the Armada 370 and Armada 38x SOCs. + +Thanks a lot to Thomas Petazzoni, Gregory Clement and Willy Tarreau +for the discussions and tips around this topic. + +Signed-off-by: Sebastien Rannou <mxs@sbrk.org> +Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> +Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com> +--- + drivers/cpuidle/cpuidle-mvebu-v7.c | 8 ++++---- + 1 file changed, 4 insertions(+), 4 deletions(-) + +--- a/drivers/cpuidle/cpuidle-mvebu-v7.c ++++ b/drivers/cpuidle/cpuidle-mvebu-v7.c +@@ -50,18 +50,18 @@ static struct cpuidle_driver armadaxp_id + .states[0] = ARM_CPUIDLE_WFI_STATE, + .states[1] = { + .enter = mvebu_v7_enter_idle, +- .exit_latency = 10, ++ .exit_latency = 100, + .power_usage = 50, +- .target_residency = 100, ++ .target_residency = 1000, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "MV CPU IDLE", + .desc = "CPU power down", + }, + .states[2] = { + .enter = mvebu_v7_enter_idle, +- .exit_latency = 100, ++ .exit_latency = 1000, + .power_usage = 5, +- .target_residency = 1000, ++ .target_residency = 10000, + .flags = CPUIDLE_FLAG_TIME_VALID | + MVEBU_V7_FLAG_DEEP_IDLE, + .name = "MV CPU DEEP IDLE", |