[PATCH V3 5/7] ARM: tegra30: clocks: add CPU low-power function into tegra_cpu_car_ops
Joseph Lo
josephl at nvidia.com
Mon Oct 29 06:28:19 EDT 2012
Add suspend, resume and rail_off_ready API into tegra_cpu_car_ops. These
functions were used for CPU powered-down state maintenance. One thing
needs to notice the rail_off_ready API only availalbe for cpu_g cluster
not cpu_lp cluster.
Signed-off-by: Joseph Lo <josephl at nvidia.com>
---
V3:
* update the commit message
V2:
* no change
---
arch/arm/mach-tegra/tegra30_clocks.c | 107 ++++++++++++++++++++++++++++++++++
arch/arm/mach-tegra/tegra_cpu_car.h | 37 ++++++++++++
2 files changed, 144 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-tegra/tegra30_clocks.c b/arch/arm/mach-tegra/tegra30_clocks.c
index 665618a..19ff1c6 100644
--- a/arch/arm/mach-tegra/tegra30_clocks.c
+++ b/arch/arm/mach-tegra/tegra30_clocks.c
@@ -32,6 +32,7 @@
#include <asm/clkdev.h>
#include <mach/iomap.h>
+#include <mach/powergate.h>
#include "clock.h"
#include "fuse.h"
@@ -310,6 +311,31 @@
#define CPU_CLOCK(cpu) (0x1 << (8 + cpu))
#define CPU_RESET(cpu) (0x1111ul << (cpu))
+#define CLK_RESET_CCLK_BURST 0x20
+#define CLK_RESET_CCLK_DIVIDER 0x24
+#define CLK_RESET_PLLX_BASE 0xe0
+#define CLK_RESET_PLLX_MISC 0xe4
+
+#define CLK_RESET_SOURCE_CSITE 0x1d4
+
+#define CLK_RESET_CCLK_BURST_POLICY_SHIFT 28
+#define CLK_RESET_CCLK_RUN_POLICY_SHIFT 4
+#define CLK_RESET_CCLK_IDLE_POLICY_SHIFT 0
+#define CLK_RESET_CCLK_IDLE_POLICY 1
+#define CLK_RESET_CCLK_RUN_POLICY 2
+#define CLK_RESET_CCLK_BURST_POLICY_PLLX 8
+
+#ifdef CONFIG_PM_SLEEP
+static struct cpu_clk_suspend_context {
+ u32 pllx_misc;
+ u32 pllx_base;
+
+ u32 cpu_burst;
+ u32 clk_csite_src;
+ u32 cclk_divider;
+} tegra30_cpu_clk_sctx;
+#endif
+
/**
* Structure defining the fields for USB UTMI clocks Parameters.
*/
@@ -2387,12 +2413,93 @@ static void tegra30_disable_cpu_clock(u32 cpu)
reg_clk_base + TEGRA_CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
}
+#ifdef CONFIG_PM_SLEEP
+static bool tegra30_cpu_rail_off_ready(void)
+{
+ unsigned int cpu_rst_status;
+ int cpu_pwr_status;
+
+ cpu_rst_status = readl(reg_clk_base +
+ TEGRA30_CLK_RST_CONTROLLER_CPU_CMPLX_STATUS);
+ cpu_pwr_status = tegra_powergate_is_powered(TEGRA_POWERGATE_CPU1) ||
+ tegra_powergate_is_powered(TEGRA_POWERGATE_CPU2) ||
+ tegra_powergate_is_powered(TEGRA_POWERGATE_CPU3);
+
+ if (((cpu_rst_status & 0xE) != 0xE) || cpu_pwr_status)
+ return false;
+
+ return true;
+}
+
+static void tegra30_cpu_clock_suspend(void)
+{
+ /* switch coresite to clk_m, save off original source */
+ tegra30_cpu_clk_sctx.clk_csite_src =
+ readl(reg_clk_base + CLK_RESET_SOURCE_CSITE);
+ writel(3<<30, reg_clk_base + CLK_RESET_SOURCE_CSITE);
+
+ tegra30_cpu_clk_sctx.cpu_burst =
+ readl(reg_clk_base + CLK_RESET_CCLK_BURST);
+ tegra30_cpu_clk_sctx.pllx_base =
+ readl(reg_clk_base + CLK_RESET_PLLX_BASE);
+ tegra30_cpu_clk_sctx.pllx_misc =
+ readl(reg_clk_base + CLK_RESET_PLLX_MISC);
+ tegra30_cpu_clk_sctx.cclk_divider =
+ readl(reg_clk_base + CLK_RESET_CCLK_DIVIDER);
+}
+
+static void tegra30_cpu_clock_resume(void)
+{
+ unsigned int reg, policy;
+
+ /* Is CPU complex already running on PLLX? */
+ reg = readl(reg_clk_base + CLK_RESET_CCLK_BURST);
+ policy = (reg >> CLK_RESET_CCLK_BURST_POLICY_SHIFT) & 0xF;
+
+ if (policy == CLK_RESET_CCLK_IDLE_POLICY)
+ reg = (reg >> CLK_RESET_CCLK_IDLE_POLICY_SHIFT) & 0xF;
+ else if (policy == CLK_RESET_CCLK_RUN_POLICY)
+ reg = (reg >> CLK_RESET_CCLK_RUN_POLICY_SHIFT) & 0xF;
+ else
+ BUG();
+
+ if (reg != CLK_RESET_CCLK_BURST_POLICY_PLLX) {
+ /* restore PLLX settings if CPU is on different PLL */
+ writel(tegra30_cpu_clk_sctx.pllx_misc,
+ reg_clk_base + CLK_RESET_PLLX_MISC);
+ writel(tegra30_cpu_clk_sctx.pllx_base,
+ reg_clk_base + CLK_RESET_PLLX_BASE);
+
+ /* wait for PLL stabilization if PLLX was enabled */
+ if (tegra30_cpu_clk_sctx.pllx_base & (1 << 30))
+ udelay(300);
+ }
+
+ /*
+ * Restore original burst policy setting for calls resulting from CPU
+ * LP2 in idle or system suspend.
+ */
+ writel(tegra30_cpu_clk_sctx.cclk_divider,
+ reg_clk_base + CLK_RESET_CCLK_DIVIDER);
+ writel(tegra30_cpu_clk_sctx.cpu_burst,
+ reg_clk_base + CLK_RESET_CCLK_BURST);
+
+ writel(tegra30_cpu_clk_sctx.clk_csite_src,
+ reg_clk_base + CLK_RESET_SOURCE_CSITE);
+}
+#endif
+
static struct tegra_cpu_car_ops tegra30_cpu_car_ops = {
.wait_for_reset = tegra30_wait_cpu_in_reset,
.put_in_reset = tegra30_put_cpu_in_reset,
.out_of_reset = tegra30_cpu_out_of_reset,
.enable_clock = tegra30_enable_cpu_clock,
.disable_clock = tegra30_disable_cpu_clock,
+#ifdef CONFIG_PM_SLEEP
+ .rail_off_ready = tegra30_cpu_rail_off_ready,
+ .suspend = tegra30_cpu_clock_suspend,
+ .resume = tegra30_cpu_clock_resume,
+#endif
};
void __init tegra30_cpu_car_ops_init(void)
diff --git a/arch/arm/mach-tegra/tegra_cpu_car.h b/arch/arm/mach-tegra/tegra_cpu_car.h
index 30d063a..9764d31 100644
--- a/arch/arm/mach-tegra/tegra_cpu_car.h
+++ b/arch/arm/mach-tegra/tegra_cpu_car.h
@@ -30,6 +30,12 @@
* CPU clock un-gate
* disable_clock:
* CPU clock gate
+ * rail_off_ready:
+ * CPU is ready for rail off
+ * suspend:
+ * save the clock settings when CPU go into low-power state
+ * resume:
+ * restore the clock settings when CPU exit low-power state
*/
struct tegra_cpu_car_ops {
void (*wait_for_reset)(u32 cpu);
@@ -37,6 +43,11 @@ struct tegra_cpu_car_ops {
void (*out_of_reset)(u32 cpu);
void (*enable_clock)(u32 cpu);
void (*disable_clock)(u32 cpu);
+#ifdef CONFIG_PM_SLEEP
+ bool (*rail_off_ready)(void);
+ void (*suspend)(void);
+ void (*resume)(void);
+#endif
};
extern struct tegra_cpu_car_ops *tegra_cpu_car_ops;
@@ -81,6 +92,32 @@ static inline void tegra_disable_cpu_clock(u32 cpu)
tegra_cpu_car_ops->disable_clock(cpu);
}
+#ifdef CONFIG_PM_SLEEP
+static inline bool tegra_cpu_rail_off_ready(void)
+{
+ if (WARN_ON(!tegra_cpu_car_ops->rail_off_ready))
+ return false;
+
+ return tegra_cpu_car_ops->rail_off_ready();
+}
+
+static inline void tegra_cpu_clock_suspend(void)
+{
+ if (WARN_ON(!tegra_cpu_car_ops->suspend))
+ return;
+
+ tegra_cpu_car_ops->suspend();
+}
+
+static inline void tegra_cpu_clock_resume(void)
+{
+ if (WARN_ON(!tegra_cpu_car_ops->resume))
+ return;
+
+ tegra_cpu_car_ops->resume();
+}
+#endif
+
void tegra20_cpu_car_ops_init(void);
void tegra30_cpu_car_ops_init(void);
--
1.7.0.4
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