[PATCH] clk: zynq: Fix EMIO clock use detection for gem0

[Michal Simek]

On 4/16/24 10:44, Ondřej Jirman wrote:
> From: Ondrej Jirman <megi at xff.cz>
> 
> According to TRM, the bit that differentiates between MIO and EMIO
> clocks is bit 6. This resolves failure to set clock when using EMIO
> clock for ethernet.

Not sure which TRM you are using but here

https://docs.amd.com/r/en-US/ug585-zynq-7000-SoC-TRM/Register-slcr-GEM0_RCLK_CTRL

SRCSEL it is bit 4 not bit 6.

> 
> Signed-off-by: Ondrej Jirman <megi at xff.cz>
> ---
>   drivers/clk/clk_zynq.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/clk/clk_zynq.c b/drivers/clk/clk_zynq.c
> index e3cefe2e0c72..78e6886a000c 100644
> --- a/drivers/clk/clk_zynq.c
> +++ b/drivers/clk/clk_zynq.c
> @@ -42,6 +42,8 @@
>   #define CLK_CTRL_DIV3X_SHIFT	20
>   #define CLK_CTRL_DIV3X_MASK	(ZYNQ_CLK_MAXDIV << CLK_CTRL_DIV3X_SHIFT)
>   
> +#define CLK_CTRL_GEM_EMIO	(1u << 6)
> +
>   DECLARE_GLOBAL_DATA_PTR;
>   
>   #ifndef CONFIG_SPL_BUILD
> @@ -161,7 +163,7 @@ static enum zynq_clk_rclk zynq_clk_get_gem_rclk(enum zynq_clk id)
>   	else
>   		clk_ctrl = readl(&slcr_base->gem1_rclk_ctrl);
>   
> -	srcsel = (clk_ctrl & CLK_CTRL_SRCSEL_MASK) >> CLK_CTRL_SRCSEL_SHIFT;
> +	srcsel = (clk_ctrl & CLK_CTRL_GEM_EMIO);

Definitely using SRCSEL_MASK is not ideal solution because mask is 0x3 and in 
gem case it is single bit. But based on description you should be getting 
correct values even with 0x3 because SHIFT is correct.

Thanks,
Michal