[PATCH 5/6] clk: tegra114: implement wait_for_reset and disable_clock for tegra_cpu_car_ops
Mike Turquette
mturquette at linaro.org
Thu May 16 15:17:23 EDT 2013
Quoting Joseph Lo (2013-05-15 03:27:23)
> 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.
>
> Cc: Mike Turquette <mturquette at linaro.org>
> Signed-off-by: Joseph Lo <josephl at nvidia.com>
Acked-by: Mike Turquette <mturquette at linaro.org>
> ---
> 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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