Re: [PATCH v2 2/3] clk: xilinx: vcu: don't set pll_ref as parent of VCU(enc/dec) clocks
From: Geert Uytterhoeven
Date: Thu Jan 02 2025 - 14:28:34 EST
Hi Rohit,
On Thu, Jan 2, 2025 at 6:04 PM Rohit Visavalia <rohit.visavalia@xxxxxxx> wrote:
> CCF will try to adjust parent clock to set desire clock frequency of
> child clock. So if pll_ref is not a fixed-clock then while setting rate
> of enc/dec clocks pll_ref may get change, which may make VCU malfunction.
>
> Signed-off-by: Rohit Visavalia <rohit.visavalia@xxxxxxx>
> ---
> Changes in v2:
> - none
> - Link to v1: https://lore.kernel.org/linux-clk/20241226122023.3439559-3-rohit.visavalia@xxxxxxx
> ---
> drivers/clk/xilinx/xlnx_vcu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/xilinx/xlnx_vcu.c b/drivers/clk/xilinx/xlnx_vcu.c
> index 88b3fd8250c2..c520ae1ba65e 100644
> --- a/drivers/clk/xilinx/xlnx_vcu.c
> +++ b/drivers/clk/xilinx/xlnx_vcu.c
> @@ -547,7 +547,7 @@ static int xvcu_register_clock_provider(struct xvcu_device *xvcu)
> return PTR_ERR(hw);
> xvcu->pll_post = hw;
>
> - parent_data[0].fw_name = "pll_ref";
> + parent_data[0].fw_name = "dummy_name";
> parent_data[1].hw = xvcu->pll_post;
>
> hws[CLK_XVCU_ENC_CORE] =
You completely ignored Stephen's comment, which suggests to not pas
CLK_SET_RATE_PARENT instead (see xvcu_clk_hw_register_leaf()).
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
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