Re: [PATCH 2/2] clk: sunxi: add and use dummy gate clocks

[Andre Przywara <andre.przywara@arm.com>]

On Fri,  6 May 2022 01:33:01 +0100
Andre Przywara <andre.przywara@arm.com> wrote:

> Some devices enumerate various clocks in their DT, and many drivers
> just blanketly try to enable all of them. This creates problems
> since we only model a few gate clocks, and the clock driver outputs
> a warning when a clock is not described:
> =========
> sunxi_set_gate: (CLK#3) unhandled
> =========
> 
> Some clocks don't have an enable bit, or are already enabled in a
> different way, so we might want to just ignore them.
> 
> Add a CCU_CLK_F_DUMMY_GATE flag that indicates that case, and define
> a GATE_DUMMY macro that can be used in the clock description array.
> Define a few clocks, used by some pinctrl devices, that way to suppress
> the runtime warnings.
> 
> Signed-off-by: Andre Przywara <andre.przywara@arm.com>

Applied to sunxi/master.

Thanks,
Andre

> ---
>  drivers/clk/sunxi/clk_h6.c    | 2 ++
>  drivers/clk/sunxi/clk_h616.c  | 2 ++
>  drivers/clk/sunxi/clk_h6_r.c  | 2 ++
>  drivers/clk/sunxi/clk_sunxi.c | 3 +++
>  include/clk/sunxi.h           | 5 +++++
>  5 files changed, 14 insertions(+)
> 
> diff --git a/drivers/clk/sunxi/clk_h6.c b/drivers/clk/sunxi/clk_h6.c
> index f4e26cbcd45..b3202342932 100644
> --- a/drivers/clk/sunxi/clk_h6.c
> +++ b/drivers/clk/sunxi/clk_h6.c
> @@ -16,6 +16,8 @@
>  static struct ccu_clk_gate h6_gates[] = {
>  	[CLK_PLL_PERIPH0]	= GATE(0x020, BIT(31)),
>  
> +	[CLK_APB1]		= GATE_DUMMY,
> +
>  	[CLK_BUS_MMC0]		= GATE(0x84c, BIT(0)),
>  	[CLK_BUS_MMC1]		= GATE(0x84c, BIT(1)),
>  	[CLK_BUS_MMC2]		= GATE(0x84c, BIT(2)),
> diff --git a/drivers/clk/sunxi/clk_h616.c b/drivers/clk/sunxi/clk_h616.c
> index 65ab44643da..80099727def 100644
> --- a/drivers/clk/sunxi/clk_h616.c
> +++ b/drivers/clk/sunxi/clk_h616.c
> @@ -15,6 +15,8 @@
>  static struct ccu_clk_gate h616_gates[] = {
>  	[CLK_PLL_PERIPH0]	= GATE(0x020, BIT(31) | BIT(27)),
>  
> +	[CLK_APB1]		= GATE_DUMMY,
> +
>  	[CLK_BUS_MMC0]		= GATE(0x84c, BIT(0)),
>  	[CLK_BUS_MMC1]		= GATE(0x84c, BIT(1)),
>  	[CLK_BUS_MMC2]		= GATE(0x84c, BIT(2)),
> diff --git a/drivers/clk/sunxi/clk_h6_r.c b/drivers/clk/sunxi/clk_h6_r.c
> index 2e0bbaa903b..c592886a258 100644
> --- a/drivers/clk/sunxi/clk_h6_r.c
> +++ b/drivers/clk/sunxi/clk_h6_r.c
> @@ -11,6 +11,8 @@
>  #include <linux/bitops.h>
>  
>  static struct ccu_clk_gate h6_r_gates[] = {
> +	[CLK_R_APB1]		= GATE_DUMMY,
> +
>  	[CLK_R_APB1_TIMER]	= GATE(0x11c, BIT(0)),
>  	[CLK_R_APB1_TWD]	= GATE(0x12c, BIT(0)),
>  	[CLK_R_APB1_PWM]	= GATE(0x13c, BIT(0)),
> diff --git a/drivers/clk/sunxi/clk_sunxi.c b/drivers/clk/sunxi/clk_sunxi.c
> index 9673b58a492..9a21367a5d0 100644
> --- a/drivers/clk/sunxi/clk_sunxi.c
> +++ b/drivers/clk/sunxi/clk_sunxi.c
> @@ -27,6 +27,9 @@ static int sunxi_set_gate(struct clk *clk, bool on)
>  	const struct ccu_clk_gate *gate = priv_to_gate(priv, clk->id);
>  	u32 reg;
>  
> +	if ((gate->flags & CCU_CLK_F_DUMMY_GATE))
> +		return 0;
> +
>  	if (!(gate->flags & CCU_CLK_F_IS_VALID)) {
>  		printf("%s: (CLK#%ld) unhandled\n", __func__, clk->id);
>  		return 0;
> diff --git a/include/clk/sunxi.h b/include/clk/sunxi.h
> index a2239b990b8..c4a9dee5ebf 100644
> --- a/include/clk/sunxi.h
> +++ b/include/clk/sunxi.h
> @@ -18,6 +18,7 @@
>  enum ccu_flags {
>  	CCU_CLK_F_IS_VALID		= BIT(0),
>  	CCU_RST_F_IS_VALID		= BIT(1),
> +	CCU_CLK_F_DUMMY_GATE		= BIT(2),
>  };
>  
>  /**
> @@ -38,6 +39,10 @@ struct ccu_clk_gate {
>  	.flags = CCU_CLK_F_IS_VALID,		\
>  }
>  
> +#define GATE_DUMMY {				\
> +	.flags = CCU_CLK_F_DUMMY_GATE,		\
> +}
> +
>  /**
>   * struct ccu_reset - ccu reset
>   * @off:	reset offset