Hi Biju,
On Wed, Oct 16, 2024 at 12:15 PM Biju Das <biju.das.jz@xxxxxxxxxxxxxx> wrote:
> While computing foutpostdiv_rate, the value of params->pl5_fracin
> is discarded, which results in the wrong refresh rate. Fix the formula
> for computing foutpostdiv_rate.
>
> Fixes: 1561380ee72f ("clk: renesas: rzg2l: Add FOUTPOSTDIV clk support")
> Signed-off-by: Hien Huynh <hien.huynh.px@xxxxxxxxxxx>
> Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> ---
> v2->v3:
> * Used mul_u32_u32() for 32-bit multiplication.
Thanks for the update!
> --- a/drivers/clk/renesas/rzg2l-cpg.c
> +++ b/drivers/clk/renesas/rzg2l-cpg.c
> @@ -557,10 +557,10 @@ rzg2l_cpg_get_foutpostdiv_rate(struct rzg2l_pll5_param *params,
> params->pl5_postdiv2 = 1;
> params->pl5_spread = 0x16;
>
> - foutpostdiv_rate =
> - EXTAL_FREQ_IN_MEGA_HZ * MEGA / params->pl5_refdiv *
> - ((((params->pl5_intin << 24) + params->pl5_fracin)) >> 24) /
> - (params->pl5_postdiv1 * params->pl5_postdiv2);
> + foutvco_rate = mul_u32_u32(EXTAL_FREQ_IN_MEGA_HZ * MEGA, (params->pl5_intin << 24) +
> + params->pl5_fracin) / params->pl5_refdiv >> 24;
The division is a 64-by-32 division, so it should use the div_u64() helper.
> + foutpostdiv_rate = DIV_ROUND_CLOSEST_ULL(foutvco_rate,
> + params->pl5_postdiv1 * params->pl5_postdiv2);
>
> return foutpostdiv_rate;
> }
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
