Subject: [PATCH 1/4] clk: rockchip: protect critical clocks from getting disabled

From: [email-masked] (Kever Yang)
Date: Tue, 12 Aug 2014 08:59:41 +0800

Heiko,

On 07/30/2014 03:12 AM, Heiko Stuebner wrote:
> The clock-tree contains clocks that should never get disabled automatically.
> One example are the base ACLKs, the base supplies for all peripherals.
>
> Therefore add a structure similar to the sunxi clock-tree to protect these
> special clocks from being disabled.
>
> Signed-off-by: Heiko Stuebner <[email-masked]>
> ---
>   drivers/clk/rockchip/clk-rk3188.c |  7 +++++++
>   drivers/clk/rockchip/clk-rk3288.c |  7 +++++++
>   drivers/clk/rockchip/clk.c        | 13 +++++++++++++
>   drivers/clk/rockchip/clk.h        |  1 +
>   4 files changed, 28 insertions(+)
>
> diff --git a/drivers/clk/rockchip/clk-rk3188.c b/drivers/clk/rockchip/clk-rk3188.c
> index a83a6d8..5aef277 100644
> --- a/drivers/clk/rockchip/clk-rk3188.c
> +++ b/drivers/clk/rockchip/clk-rk3188.c
> @@ -599,6 +599,11 @@ static struct rockchip_clk_branch rk3188_clk_branches[] __initdata = {
>   	GATE(ACLK_GPS, "aclk_gps", "aclk_peri", 0, RK2928_CLKGATE_CON(8), 13, GFLAGS),
>   };
>   
> +static const char *rk3188_critical_clocks[] __initconst = {
> +	"aclk_cpu",
> +	"aclk_peri",
> +};
> +
>   static void __init rk3188_common_clk_init(struct device_node *np)
>   {
>   	void __iomem *reg_base;
> @@ -628,6 +633,8 @@ static void __init rk3188_common_clk_init(struct device_node *np)
>   				   RK3188_GRF_SOC_STATUS);
>   	rockchip_clk_register_branches(common_clk_branches,
>   				  ARRAY_SIZE(common_clk_branches));
> +	rockchip_clk_protect_critical(rk3188_critical_clocks,
> +				      ARRAY_SIZE(rk3188_critical_clocks));
>   
>   	rockchip_register_softrst(np, 9, reg_base + RK2928_SOFTRST_CON(0),
>   				  ROCKCHIP_SOFTRST_HIWORD_MASK);
> diff --git a/drivers/clk/rockchip/clk-rk3288.c b/drivers/clk/rockchip/clk-rk3288.c
> index 0d8c6c5..6c6f954 100644
> --- a/drivers/clk/rockchip/clk-rk3288.c
> +++ b/drivers/clk/rockchip/clk-rk3288.c
> @@ -680,6 +680,11 @@ static struct rockchip_clk_branch rk3288_clk_branches[] __initdata = {
>   	GATE(0, "pclk_isp_in", "ext_isp", 0, RK3288_CLKGATE_CON(16), 3, GFLAGS),
>   };
>   
> +static const char *rk3288_critical_clocks[] __initconst = {
> +	"aclk_cpu",
> +	"aclk_peri",
> +};
> +
>   static void __init rk3288_clk_init(struct device_node *np)
>   {
>   	void __iomem *reg_base;
> @@ -710,6 +715,8 @@ static void __init rk3288_clk_init(struct device_node *np)
>   				   RK3288_GRF_SOC_STATUS);
>   	rockchip_clk_register_branches(rk3288_clk_branches,
>   				  ARRAY_SIZE(rk3288_clk_branches));
> +	rockchip_clk_protect_critical(rk3288_critical_clocks,
> +				      ARRAY_SIZE(rk3288_critical_clocks));
>   
>   	rockchip_register_softrst(np, 9, reg_base + RK3288_SOFTRST_CON(0),
>   				  ROCKCHIP_SOFTRST_HIWORD_MASK);
> diff --git a/drivers/clk/rockchip/clk.c b/drivers/clk/rockchip/clk.c
> index 278cf9d..9189f1b 100644
> --- a/drivers/clk/rockchip/clk.c
> +++ b/drivers/clk/rockchip/clk.c
> @@ -242,3 +242,16 @@ void __init rockchip_clk_register_branches(
>   		rockchip_clk_add_lookup(clk, list->id);
>   	}
>   }
> +
> +void __init rockchip_clk_protect_critical(const char *clocks[], int nclocks)
> +{
> +	int i;
> +
> +	/* Protect the clocks that needs to stay on */
> +	for (i = 0; i < nclocks; i++) {
> +		struct clk *clk = __clk_lookup(clocks[i]);
> +
> +		if (clk)
> +			clk_prepare_enable(clk);
> +	}
> +}
> diff --git a/drivers/clk/rockchip/clk.h b/drivers/clk/rockchip/clk.h
> index 887cbde..2b0bca1 100644
> --- a/drivers/clk/rockchip/clk.h
> +++ b/drivers/clk/rockchip/clk.h
> @@ -329,6 +329,7 @@ void rockchip_clk_register_branches(struct rockchip_clk_branch *clk_list,
>   				    unsigned int nr_clk);
>   void rockchip_clk_register_plls(struct rockchip_pll_clock *pll_list,
>   				unsigned int nr_pll, int grf_lock_offset);
> +void rockchip_clk_protect_critical(const char *clocks[], int nclocks);
>   
>   #define ROCKCHIP_SOFTRST_HIWORD_MASK	BIT(0)
>   

Tested-by: Kever Yang <[email-masked]>