[PATCH] clk: zynqmp: Add support for dpll clock source

[Michal Simek]

On 6/18/25 11:43, Padmarao Begari wrote:
> The clock driver fails to correctly calculate the PLL clock
> rate for peripherals when using the DPLL as the clock source.
> The DPLL operates within the full power domain, while peripheral
> clocks reside in the low power domain. To ensure accurate PLL
> clock rate computation when the peripheral clock source is set
> to DPLL, the DPLL-to-LPD cross divisor is used.
> 
> Signed-off-by: Padmarao Begari <padmarao.begari at amd.com>
> ---
>   drivers/clk/clk_zynqmp.c | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
> 
> diff --git a/drivers/clk/clk_zynqmp.c b/drivers/clk/clk_zynqmp.c
> index a8239e228cf..4f67c958d0f 100644
> --- a/drivers/clk/clk_zynqmp.c
> +++ b/drivers/clk/clk_zynqmp.c
> @@ -108,6 +108,8 @@ static const resource_size_t zynqmp_crl_apb_clkc_base = 0xff5e0020;
>   #define PLLCTRL_POST_SRC_MASK	(0x7 << PLLCTRL_POST_SRC_SHFT)
>   #define PLLCTRL_PRE_SRC_SHFT	20
>   #define PLLCTRL_PRE_SRC_MASK	(0x7 << PLLCTRL_PRE_SRC_SHFT)
> +#define PLL_TO_LPD_DIV_SHIFT	8
> +#define PLL_TO_LPD_DIV_MASK	(0x3f << PLL_TO_LPD_DIV_SHIFT)
>   
>   #define NUM_MIO_PINS	77
>   
> @@ -334,6 +336,8 @@ static u32 zynqmp_clk_get_register(enum zynqmp_clk id)
>   		return CRF_APB_TOPSW_LSBUS_CTRL;
>   	case iopll_to_fpd:
>   		return CRL_APB_IOPLL_TO_FPD_CTRL;
> +	case dpll_to_lpd:
> +		return CRF_APB_DPLL_TO_LPD_CTRL;
>   	default:
>   		debug("Invalid clk id%d\n", id);
>   	}
> @@ -397,6 +401,22 @@ static ulong zynqmp_clk_get_pll_rate(struct zynqmp_clk_priv *priv,
>   	if (clk_ctrl & (1 << 16))
>   		freq /= 2;
>   
> +	if (id == dpll) {
> +		u32 dpll_lpd_reg, cross_div;
> +
> +		dpll_lpd_reg = zynqmp_clk_get_register(dpll_to_lpd);
> +
> +		ret = zynqmp_mmio_read(dpll_lpd_reg, &cross_div);
> +		if (ret) {
> +			printf("%s mio read fail\n", __func__);
> +			return -EIO;
> +		}
> +
> +		cross_div = (cross_div & PLL_TO_LPD_DIV_MASK) >>
> +			     PLL_TO_LPD_DIV_SHIFT;
> +		freq /= cross_div;
> +	}
> +
>   	return freq;
>   }
>   

Applied.
M