[U-Boot] [PATCH 1/4] rockchip: clk: rk3399: handle clk_enable requests for USB3

[Kever Yang]

Hi Mark,

    Thanks for your patches, and see comments below.

On 06/30/2019 12:29 AM, Mark Kettenis wrote:
> The "simple" OF glue layer for the Designware USB3 core enables
> all refernced clocks.  These need to be need to be implemented
> otherwise the driver fails to probe.  A dummy implementation
> that simply returns success is sufficient since the RK3399 comes
> out of reset with all clock gates open.
>
> Signed-off-by: Mark Kettenis <kettenis at openbsd.org>
> ---
>  drivers/clk/rockchip/clk_rk3399.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
>
> diff --git a/drivers/clk/rockchip/clk_rk3399.c b/drivers/clk/rockchip/clk_rk3399.c
> index 79007b8682..d9950c159b 100644
> --- a/drivers/clk/rockchip/clk_rk3399.c
> +++ b/drivers/clk/rockchip/clk_rk3399.c
> @@ -1080,6 +1080,18 @@ static int rk3399_clk_enable(struct clk *clk)
>  	case PCLK_GMAC:
>  		/* Required to successfully probe the Designware GMAC driver */
>  		return 0;
> +
> +	case SCLK_USB3OTG0_REF:
> +	case SCLK_USB3OTG1_REF:
> +	case SCLK_USB3OTG0_SUSPEND:
> +	case SCLK_USB3OTG1_SUSPEND:
> +	case ACLK_USB3OTG0:
> +	case ACLK_USB3OTG1:
> +	case ACLK_USB3_RKSOC_AXI_PERF:
> +	case ACLK_USB3:
> +	case ACLK_USB3_GRF:
> +		/* Required to successfully probe the Designware USB3 driver */
> +		return 0;

This look waist of cpu cycles, we don't actually need to init clock for
rk3399 in
U-Boot, can we just delete the clock node in dts(in -u-boot.dtsi) and
also make
the probe successfully?

Thanks,
- Kever
>  	}
>  
>  	debug("%s: unsupported clk %ld\n", __func__, clk->id);