Re: [PATCH] clk: imx: pll14xx: fix recalc_rate for negative kdiv

From: Abel Vesa
Date: Wed Feb 15 2023 - 07:24:24 EST


On 22-12-10 15:38:35, Kevin Groeneveld wrote:
> kdiv is a signed 16 bit value in the DEV_CTL1 register. Commit
> 53990cf9d5b4 ("clk: imx: pll14xx: consolidate rate calculation") changed
> the kdiv variable from a short int to just int. When the value read from
> the DIV_CTL1 register is assigned directly to an int the sign of the value
> is lost resulting in incorrect results when the value is negative. Adding
> a s16 cast to the register value fixes the issue.
>
> Fixes: 53990cf9d5b4 ("clk: imx: pll14xx: consolidate rate calculation")
> Signed-off-by: Kevin Groeneveld <kgroeneveld@xxxxxxxxxxxx>

Reviewed-by: Abel Vesa <abel.vesa@xxxxxxxxxx>

Stephen, can you pick this up through fixes?
> ---
> drivers/clk/imx/clk-pll14xx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/imx/clk-pll14xx.c b/drivers/clk/imx/clk-pll14xx.c
> index 1d0f79e9c346..d12194d17b10 100644
> --- a/drivers/clk/imx/clk-pll14xx.c
> +++ b/drivers/clk/imx/clk-pll14xx.c
> @@ -254,7 +254,7 @@ static unsigned long clk_pll14xx_recalc_rate(struct clk_hw *hw,
>
> if (pll->type == PLL_1443X) {
> pll_div_ctl1 = readl_relaxed(pll->base + DIV_CTL1);
> - kdiv = FIELD_GET(KDIV_MASK, pll_div_ctl1);
> + kdiv = (s16)FIELD_GET(KDIV_MASK, pll_div_ctl1);
> } else {
> kdiv = 0;
> }
> --
> 2.17.1
>