2023-06-14 14:45:41

by Alibek Omarov

[permalink] [raw]
Subject: [PATCH] clk: rockchip: rk3568: Fix PLL rate setting for 78.75MHz

PLL rate on RK356x is calculated through the simple formula:
((24000000 / _refdiv) * _fbdiv) / (_postdiv1 * _postdiv2)

The PLL rate setting for 78.75MHz seems to be copied from 96MHz
so this patch fixes it and configures it properly.

Signed-off-by: Alibek Omarov <[email protected]>
Fixes: 842f4cb72639 ("clk: rockchip: Add more PLL rates for rk3568")
---
drivers/clk/rockchip/clk-rk3568.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/rockchip/clk-rk3568.c b/drivers/clk/rockchip/clk-rk3568.c
index 5dae960af4ce..48b8d06c305c 100644
--- a/drivers/clk/rockchip/clk-rk3568.c
+++ b/drivers/clk/rockchip/clk-rk3568.c
@@ -82,7 +82,7 @@ static struct rockchip_pll_rate_table rk3568_pll_rates[] = {
RK3036_PLL_RATE(101000000, 1, 101, 6, 4, 1, 0),
RK3036_PLL_RATE(100000000, 1, 150, 6, 6, 1, 0),
RK3036_PLL_RATE(96000000, 1, 96, 6, 4, 1, 0),
- RK3036_PLL_RATE(78750000, 1, 96, 6, 4, 1, 0),
+ RK3036_PLL_RATE(78750000, 4, 315, 6, 4, 1, 0),
RK3036_PLL_RATE(74250000, 2, 99, 4, 4, 1, 0),
{ /* sentinel */ },
};
--
2.34.1



2023-06-26 10:08:17

by Sascha Hauer

[permalink] [raw]
Subject: Re: [PATCH] clk: rockchip: rk3568: Fix PLL rate setting for 78.75MHz

On Wed, Jun 14, 2023 at 04:47:50PM +0300, Alibek Omarov wrote:
> PLL rate on RK356x is calculated through the simple formula:
> ((24000000 / _refdiv) * _fbdiv) / (_postdiv1 * _postdiv2)
>
> The PLL rate setting for 78.75MHz seems to be copied from 96MHz
> so this patch fixes it and configures it properly.
>
> Signed-off-by: Alibek Omarov <[email protected]>
> Fixes: 842f4cb72639 ("clk: rockchip: Add more PLL rates for rk3568")

Reviewed-by: Sascha Hauer <[email protected]>

> ---
> drivers/clk/rockchip/clk-rk3568.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/clk/rockchip/clk-rk3568.c b/drivers/clk/rockchip/clk-rk3568.c
> index 5dae960af4ce..48b8d06c305c 100644
> --- a/drivers/clk/rockchip/clk-rk3568.c
> +++ b/drivers/clk/rockchip/clk-rk3568.c
> @@ -82,7 +82,7 @@ static struct rockchip_pll_rate_table rk3568_pll_rates[] = {
> RK3036_PLL_RATE(101000000, 1, 101, 6, 4, 1, 0),
> RK3036_PLL_RATE(100000000, 1, 150, 6, 6, 1, 0),
> RK3036_PLL_RATE(96000000, 1, 96, 6, 4, 1, 0),
> - RK3036_PLL_RATE(78750000, 1, 96, 6, 4, 1, 0),
> + RK3036_PLL_RATE(78750000, 4, 315, 6, 4, 1, 0),

refdiv = 4
fbdiv = 315
postdiv1 = 6
postdiv2 = 4

((24000000 / 4) * 315) / 6 / 4 = 78750000

LGTM

Sascha

--
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2023-06-26 11:21:55

by Heiko Stübner

[permalink] [raw]
Subject: Re: [PATCH] clk: rockchip: rk3568: Fix PLL rate setting for 78.75MHz

On Wed, 14 Jun 2023 16:47:50 +0300, Alibek Omarov wrote:
> PLL rate on RK356x is calculated through the simple formula:
> ((24000000 / _refdiv) * _fbdiv) / (_postdiv1 * _postdiv2)
>
> The PLL rate setting for 78.75MHz seems to be copied from 96MHz
> so this patch fixes it and configures it properly.
>
>
> [...]

Applied, thanks!

[1/1] clk: rockchip: rk3568: Fix PLL rate setting for 78.75MHz
commit: 17c6d0c5f2a4dd3f48e300d77c93780d5c36a37e

Best regards,
--
Heiko Stuebner <[email protected]>