[PATCH v7 4/5] ARM: EXYNOS: PM: fix register setup for AFTR mode code
From: Bartlomiej Zolnierkiewicz <hidden>
Date: 2014-09-24 12:25:46
Also in:
linux-arm-kernel, linux-samsung-soc, linux-tegra, lkml
Subsystem:
arm port, cpuidle driver - arm exynos, the rest · Maintainers:
Russell King, Daniel Lezcano, Kukjin Kim, Linus Torvalds
Add S5P_CENTRAL_SEQ_OPTION register setup to cpuidle AFTR mode code by moving the relevant code from exynos_pm_suspend() (used only by suspend) to exynos_pm_central_suspend() (used by both suspend and AFTR). Without this setup AFTR mode doesn't show any benefit over WFI one (at least on Exynos4412 SoC). When this setup is applied AFTR mode reduces power consumption by ~12% (as measured on Trats2 board). This change is a preparation for adding secure firmware support to EXYNOS cpuidle driver. Signed-off-by: Bartlomiej Zolnierkiewicz <redacted> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> --- v7: - no changes arch/arm/mach-exynos/pm.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/arch/arm/mach-exynos/pm.c b/arch/arm/mach-exynos/pm.c
index 6796fce..16c5c32 100644
--- a/arch/arm/mach-exynos/pm.c
+++ b/arch/arm/mach-exynos/pm.c@@ -196,6 +196,10 @@ static void exynos_pm_central_suspend(void) tmp = pmu_raw_readl(S5P_CENTRAL_SEQ_CONFIGURATION); tmp &= ~S5P_CENTRAL_LOWPWR_CFG; pmu_raw_writel(tmp, S5P_CENTRAL_SEQ_CONFIGURATION); + + /* Setting SEQ_OPTION register */ + pmu_raw_writel(S5P_USE_STANDBY_WFI0 | S5P_USE_STANDBY_WFE0, + S5P_CENTRAL_SEQ_OPTION); } static int exynos_pm_central_resume(void)
@@ -321,15 +325,8 @@ static void exynos_pm_prepare(void) static int exynos_pm_suspend(void) { - unsigned long tmp; - exynos_pm_central_suspend(); - /* Setting SEQ_OPTION register */ - - tmp = (S5P_USE_STANDBY_WFI0 | S5P_USE_STANDBY_WFE0); - pmu_raw_writel(tmp, S5P_CENTRAL_SEQ_OPTION); - if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9) exynos_cpu_save_register();
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1.8.2.3