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authorOlof Johansson <olof@lixom.net>2013-02-05 12:46:11 -0800
committerOlof Johansson <olof@lixom.net>2013-02-05 12:46:18 -0800
commitc8bfea3636215e50b519e6fdb29f1bf776b0f166 (patch)
treeb580cc2463e3adefaf761af46e95146979887c58 /drivers/clk
parentceca718f21270dcd7cdf7e124f15b35cb68eca13 (diff)
parent1d328606c66b9bb1c0552f585943d596f37ae3b9 (diff)
downloadvexpress-lsk-c8bfea3636215e50b519e6fdb29f1bf776b0f166.tar.gz
Merge tag 'tegra-for-3.9-soc-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra into next/soc
From Stephen Warren: ARM: tegra: cpuidle enhancements This pull request implements a new "LP2" cpuidle state for Tegra20, which makes use of the couple cpuidle feature. It is based on (most of) the previous pull request, with tag tegra-for-3.9-soc-usb. * tag 'tegra-for-3.9-soc-cpuidle' of git://git.kernel.org/pub/scm/linux/kernel/git/swarren/linux-tegra: ARM: tegra20: cpuidle: apply coupled cpuidle for powered-down mode ARM: tegra20: flowctrl: add support for cpu_suspend_enter/exit clk: tegra20: Implementing CPU low-power function for tegra_cpu_car_ops ARM: tegra20: cpuidle: add powered-down state for secondary CPU ARM: tegra: add pending SGI checking API Signed-off-by: Olof Johansson <olof@lixom.net>
Diffstat (limited to 'drivers/clk')
-rw-r--r--drivers/clk/tegra/clk-tegra20.c93
1 files changed, 93 insertions, 0 deletions
diff --git a/drivers/clk/tegra/clk-tegra20.c b/drivers/clk/tegra/clk-tegra20.c
index 077d5b9ffe2..5d41569883a 100644
--- a/drivers/clk/tegra/clk-tegra20.c
+++ b/drivers/clk/tegra/clk-tegra20.c
@@ -21,6 +21,7 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/clk/tegra.h>
+#include <linux/delay.h>
#include "clk.h"
@@ -104,6 +105,13 @@
#define SUPER_SCLK_DIVIDER 0x2c
#define CLK_SYSTEM_RATE 0x30
+#define CCLK_BURST_POLICY_SHIFT 28
+#define CCLK_RUN_POLICY_SHIFT 4
+#define CCLK_IDLE_POLICY_SHIFT 0
+#define CCLK_IDLE_POLICY 1
+#define CCLK_RUN_POLICY 2
+#define CCLK_BURST_POLICY_PLLX 8
+
#define CLK_SOURCE_I2S1 0x100
#define CLK_SOURCE_I2S2 0x104
#define CLK_SOURCE_SPDIF_OUT 0x108
@@ -169,6 +177,17 @@
#define CPU_CLOCK(cpu) (0x1 << (8 + cpu))
#define CPU_RESET(cpu) (0x1111ul << (cpu))
+#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;
+} tegra20_cpu_clk_sctx;
+#endif
+
static int periph_clk_enb_refcnt[CLK_OUT_ENB_NUM * 32];
static void __iomem *clk_base;
@@ -1136,12 +1155,86 @@ static void tegra20_disable_cpu_clock(u32 cpu)
clk_base + TEGRA_CLK_RST_CONTROLLER_CLK_CPU_CMPLX);
}
+#ifdef CONFIG_PM_SLEEP
+static bool tegra20_cpu_rail_off_ready(void)
+{
+ unsigned int cpu_rst_status;
+
+ cpu_rst_status = readl(clk_base +
+ TEGRA_CLK_RST_CONTROLLER_RST_CPU_CMPLX_SET);
+
+ return !!(cpu_rst_status & 0x2);
+}
+
+static void tegra20_cpu_clock_suspend(void)
+{
+ /* switch coresite to clk_m, save off original source */
+ tegra20_cpu_clk_sctx.clk_csite_src =
+ readl(clk_base + CLK_SOURCE_CSITE);
+ writel(3<<30, clk_base + CLK_SOURCE_CSITE);
+
+ tegra20_cpu_clk_sctx.cpu_burst =
+ readl(clk_base + CCLK_BURST_POLICY);
+ tegra20_cpu_clk_sctx.pllx_base =
+ readl(clk_base + PLLX_BASE);
+ tegra20_cpu_clk_sctx.pllx_misc =
+ readl(clk_base + PLLX_MISC);
+ tegra20_cpu_clk_sctx.cclk_divider =
+ readl(clk_base + SUPER_CCLK_DIVIDER);
+}
+
+static void tegra20_cpu_clock_resume(void)
+{
+ unsigned int reg, policy;
+
+ /* Is CPU complex already running on PLLX? */
+ reg = readl(clk_base + CCLK_BURST_POLICY);
+ policy = (reg >> CCLK_BURST_POLICY_SHIFT) & 0xF;
+
+ if (policy == CCLK_IDLE_POLICY)
+ reg = (reg >> CCLK_IDLE_POLICY_SHIFT) & 0xF;
+ else if (policy == CCLK_RUN_POLICY)
+ reg = (reg >> CCLK_RUN_POLICY_SHIFT) & 0xF;
+ else
+ BUG();
+
+ if (reg != CCLK_BURST_POLICY_PLLX) {
+ /* restore PLLX settings if CPU is on different PLL */
+ writel(tegra20_cpu_clk_sctx.pllx_misc,
+ clk_base + PLLX_MISC);
+ writel(tegra20_cpu_clk_sctx.pllx_base,
+ clk_base + PLLX_BASE);
+
+ /* wait for PLL stabilization if PLLX was enabled */
+ if (tegra20_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(tegra20_cpu_clk_sctx.cclk_divider,
+ clk_base + SUPER_CCLK_DIVIDER);
+ writel(tegra20_cpu_clk_sctx.cpu_burst,
+ clk_base + CCLK_BURST_POLICY);
+
+ writel(tegra20_cpu_clk_sctx.clk_csite_src,
+ clk_base + CLK_SOURCE_CSITE);
+}
+#endif
+
static struct tegra_cpu_car_ops tegra20_cpu_car_ops = {
.wait_for_reset = tegra20_wait_cpu_in_reset,
.put_in_reset = tegra20_put_cpu_in_reset,
.out_of_reset = tegra20_cpu_out_of_reset,
.enable_clock = tegra20_enable_cpu_clock,
.disable_clock = tegra20_disable_cpu_clock,
+#ifdef CONFIG_PM_SLEEP
+ .rail_off_ready = tegra20_cpu_rail_off_ready,
+ .suspend = tegra20_cpu_clock_suspend,
+ .resume = tegra20_cpu_clock_resume,
+#endif
};
static __initdata struct tegra_clk_init_table init_table[] = {