[PATCH v2] ARM: Exynos4: read initial state of power domain from hw registers

Marek Szyprowski m.szyprowski at samsung.com
Tue Apr 10 08:39:39 EDT 2012


Some bootloaders disable unused power domains, so kernel code should
read the actual state from the hardware registers instead of assuming
that their initial state is 'on'.

Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
 arch/arm/mach-exynos/pm_domains.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
index 13b3068..26fc47d 100644
--- a/arch/arm/mach-exynos/pm_domains.c
+++ b/arch/arm/mach-exynos/pm_domains.c
@@ -151,9 +151,12 @@ static __init int exynos4_pm_init_power_domain(void)
 	if (of_have_populated_dt())
 		return exynos_pm_dt_parse_domains();
 
-	for (idx = 0; idx < ARRAY_SIZE(exynos4_pm_domains); idx++)
-		pm_genpd_init(&exynos4_pm_domains[idx]->pd, NULL,
-				exynos4_pm_domains[idx]->is_off);
+	for (idx = 0; idx < ARRAY_SIZE(exynos4_pm_domains); idx++) {
+		struct exynos_pm_domain *pd = exynos4_pm_domains[idx];
+		int on = __raw_readl(pd->base + 0x4) & S5P_INT_LOCAL_PWR_EN;
+
+		pm_genpd_init(&pd->pd, NULL, !on);
+	}
 
 #ifdef CONFIG_S5P_DEV_FIMD0
 	exynos_pm_add_dev_to_genpd(&s5p_device_fimd0, &exynos4_pd_lcd0);
-- 
1.7.1.569.g6f426




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