[PATCH V2 5/6] clk: tegra114: implement wait_for_reset and disable_clock for tegra_cpu_car_ops
Joseph Lo
josephl at nvidia.com
Mon May 20 06:39:28 EDT 2013
The conventional CPU hotplug sequence on the other Tegra chips, we will also
clock gate the CPU in tegra_cpu_kill() after the CPU was power gated. For
Tegra114, the flow controller will clock gate the CPU after the power down
sequence. But we still need to implement a empty function for disable_clock
to avoid kernel warning message.
Signed-off-by: Joseph Lo <josephl at nvidia.com>
Acked-by: Mike Turquette <mturquette at linaro.org>
---
V2:
* no change
---
drivers/clk/tegra/clk-tegra114.c | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
diff --git a/drivers/clk/tegra/clk-tegra114.c b/drivers/clk/tegra/clk-tegra114.c
index d78e16e..40d939d 100644
--- a/drivers/clk/tegra/clk-tegra114.c
+++ b/drivers/clk/tegra/clk-tegra114.c
@@ -250,6 +250,9 @@
#define CLK_SOURCE_XUSB_DEV_SRC 0x60c
#define CLK_SOURCE_EMC 0x19c
+/* Tegra CPU clock and reset control regs */
+#define CLK_RST_CONTROLLER_CPU_CMPLX_STATUS 0x470
+
static int periph_clk_enb_refcnt[CLK_OUT_ENB_NUM * 32];
static void __iomem *clk_base;
@@ -2000,7 +2003,25 @@ static __init void tegra114_periph_clk_init(void __iomem *clk_base)
}
}
-static struct tegra_cpu_car_ops tegra114_cpu_car_ops;
+/* Tegra114 CPU clock and reset control functions */
+static void tegra114_wait_cpu_in_reset(u32 cpu)
+{
+ unsigned int reg;
+
+ do {
+ reg = readl(clk_base + CLK_RST_CONTROLLER_CPU_CMPLX_STATUS);
+ cpu_relax();
+ } while (!(reg & (1 << cpu))); /* check CPU been reset or not */
+}
+static void tegra114_disable_cpu_clock(u32 cpu)
+{
+ /* flow controller would take care in the power sequence. */
+}
+
+static struct tegra_cpu_car_ops tegra114_cpu_car_ops = {
+ .wait_for_reset = tegra114_wait_cpu_in_reset,
+ .disable_clock = tegra114_disable_cpu_clock,
+};
static const struct of_device_id pmc_match[] __initconst = {
{ .compatible = "nvidia,tegra114-pmc" },
--
1.8.2.2
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