diff options
| -rw-r--r-- | Documentation/devicetree/bindings/arm/exynos/power_domain.txt | 20 | ||||
| -rw-r--r-- | arch/arm/mach-exynos/pm_domains.c | 61 |
2 files changed, 80 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt index 5216b419016a..8b4f7b7fe88b 100644 --- a/Documentation/devicetree/bindings/arm/exynos/power_domain.txt +++ b/Documentation/devicetree/bindings/arm/exynos/power_domain.txt @@ -9,6 +9,18 @@ Required Properties: - reg: physical base address of the controller and length of memory mapped region. +Optional Properties: +- clocks: List of clock handles. The parent clocks of the input clocks to the + devices in this power domain are set to oscclk before power gating + and restored back after powering on a domain. This is required for + all domains which are powered on and off and not required for unused + domains. +- clock-names: The following clocks can be specified: + - oscclk: Oscillator clock. + - pclkN, clkN: Pairs of parent of input clock and input clock to the + devices in this power domain. Maximum of 4 pairs (N = 0 to 3) + are supported currently. + Node of a device using power domains must have a samsung,power-domain property defined with a phandle to respective power domain. @@ -19,6 +31,14 @@ Example: reg = <0x10023C00 0x10>; }; + mfc_pd: power-domain@10044060 { + compatible = "samsung,exynos4210-pd"; + reg = <0x10044060 0x20>; + clocks = <&clock CLK_FIN_PLL>, <&clock CLK_MOUT_SW_ACLK333>, + <&clock CLK_MOUT_USER_ACLK333>; + clock-names = "oscclk", "pclk0", "clk0"; + }; + Example of the node using power domain: node { diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c index fe6570ebbdde..797cb134bfff 100644 --- a/arch/arm/mach-exynos/pm_domains.c +++ b/arch/arm/mach-exynos/pm_domains.c @@ -17,6 +17,7 @@ #include <linux/err.h> #include <linux/slab.h> #include <linux/pm_domain.h> +#include <linux/clk.h> #include <linux/delay.h> #include <linux/of_address.h> #include <linux/of_platform.h> @@ -24,6 +25,8 @@ #include "regs-pmu.h" +#define MAX_CLK_PER_DOMAIN 4 + /* * Exynos specific wrapper around the generic power domain */ @@ -32,6 +35,9 @@ struct exynos_pm_domain { char const *name; bool is_off; struct generic_pm_domain pd; + struct clk *oscclk; + struct clk *clk[MAX_CLK_PER_DOMAIN]; + struct clk *pclk[MAX_CLK_PER_DOMAIN]; }; static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on) @@ -44,6 +50,19 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on) pd = container_of(domain, struct exynos_pm_domain, pd); base = pd->base; + /* Set oscclk before powering off a domain*/ + if (!power_on) { + int i; + + for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) { + if (IS_ERR(pd->clk[i])) + break; + if (clk_set_parent(pd->clk[i], pd->oscclk)) + pr_err("%s: error setting oscclk as parent to clock %d\n", + pd->name, i); + } + } + pwr = power_on ? S5P_INT_LOCAL_PWR_EN : 0; __raw_writel(pwr, base); @@ -60,6 +79,20 @@ static int exynos_pd_power(struct generic_pm_domain *domain, bool power_on) cpu_relax(); usleep_range(80, 100); } + + /* Restore clocks after powering on a domain*/ + if (power_on) { + int i; + + for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) { + if (IS_ERR(pd->clk[i])) + break; + if (clk_set_parent(pd->clk[i], pd->pclk[i])) + pr_err("%s: error setting parent to clock%d\n", + pd->name, i); + } + } + return 0; } @@ -152,9 +185,11 @@ static __init int exynos4_pm_init_power_domain(void) for_each_compatible_node(np, NULL, "samsung,exynos4210-pd") { struct exynos_pm_domain *pd; - int on; + int on, i; + struct device *dev; pdev = of_find_device_by_node(np); + dev = &pdev->dev; pd = kzalloc(sizeof(*pd), GFP_KERNEL); if (!pd) { @@ -170,6 +205,30 @@ static __init int exynos4_pm_init_power_domain(void) pd->pd.power_on = exynos_pd_power_on; pd->pd.of_node = np; + pd->oscclk = clk_get(dev, "oscclk"); + if (IS_ERR(pd->oscclk)) + goto no_clk; + + for (i = 0; i < MAX_CLK_PER_DOMAIN; i++) { + char clk_name[8]; + + snprintf(clk_name, sizeof(clk_name), "clk%d", i); + pd->clk[i] = clk_get(dev, clk_name); + if (IS_ERR(pd->clk[i])) + break; + snprintf(clk_name, sizeof(clk_name), "pclk%d", i); + pd->pclk[i] = clk_get(dev, clk_name); + if (IS_ERR(pd->pclk[i])) { + clk_put(pd->clk[i]); + pd->clk[i] = ERR_PTR(-EINVAL); + break; + } + } + + if (IS_ERR(pd->clk[0])) + clk_put(pd->oscclk); + +no_clk: platform_set_drvdata(pdev, pd); on = __raw_readl(pd->base + 0x4) & S5P_INT_LOCAL_PWR_EN; |