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* [PATCH] phy: phy-rockchip-samsung-hdptx: Fix PHY PLL output 50.25MHz error
@ 2025-04-25  2:37 Algea Cao
  2025-04-25  6:12 ` Cristian Ciocaltea
  0 siblings, 1 reply; 2+ messages in thread
From: Algea Cao @ 2025-04-25  2:37 UTC (permalink / raw)
  To: vkoul, kishon, heiko, cristian.ciocaltea, andy.yan
  Cc: linux-phy, linux-arm-kernel, linux-rockchip, linux-kernel, Algea Cao

When using HDMI PLL frequency division coefficient at 50.25MHz
that calculated by rk_hdptx_phy_clk_pll_calc(), it is failed to
get PHY LANE lock. Although the calculated values are within the
allowable range of PHY PLL configuration.

So we manually calculated PHY PLL frequency division coefficient
at 50.25Mhz and added it to ropll_tmds_cfg. Manually calculated
value  can make PHY LANE lock normally and output 50.25MHz normally.

Signed-off-by: Algea Cao <algea.cao@rock-chips.com>
---
 drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
index fe7c05748356..77236f012a1f 100644
--- a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
+++ b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
@@ -476,6 +476,8 @@ static const struct ropll_config ropll_tmds_cfg[] = {
 	  1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
 	{ 650000, 162, 162, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 54, 0, 16, 4, 1,
 	  1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
+	{ 502500, 84, 84, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 11, 1, 4, 5,
+	  4, 11, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
 	{ 337500, 0x70, 0x70, 1, 1, 0xf, 1, 1, 1, 1, 1, 1, 1, 0x2, 0, 0x01, 5,
 	  1, 1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
 	{ 400000, 100, 100, 1, 1, 11, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
-- 
2.43.0


^ permalink raw reply	[flat|nested] 2+ messages in thread

* Re: [PATCH] phy: phy-rockchip-samsung-hdptx: Fix PHY PLL output 50.25MHz error
  2025-04-25  2:37 [PATCH] phy: phy-rockchip-samsung-hdptx: Fix PHY PLL output 50.25MHz error Algea Cao
@ 2025-04-25  6:12 ` Cristian Ciocaltea
  0 siblings, 0 replies; 2+ messages in thread
From: Cristian Ciocaltea @ 2025-04-25  6:12 UTC (permalink / raw)
  To: Algea Cao, vkoul, kishon, heiko, andy.yan
  Cc: linux-phy, linux-arm-kernel, linux-rockchip, linux-kernel

Hi Algea,

On 4/25/25 5:37 AM, Algea Cao wrote:
> When using HDMI PLL frequency division coefficient at 50.25MHz
> that calculated by rk_hdptx_phy_clk_pll_calc(), it is failed to

s/that/that is/
s/is failed/it fails/

> get PHY LANE lock. Although the calculated values are within the
> allowable range of PHY PLL configuration.
> 
> So we manually calculated PHY PLL frequency division coefficient
> at 50.25Mhz and added it to ropll_tmds_cfg. Manually calculated
> value  can make PHY LANE lock normally and output 50.25MHz normally.

I'd reword this paragraph using imperative sentences, e.g.:

In order to fix the PHY LANE lock error and provide the expected
50.25MHz output, manually compute the required PHY PLL frequency
division coefficient and add it to ropll_tmds_cfg configuration table.

> Signed-off-by: Algea Cao <algea.cao@rock-chips.com>
> ---
>  drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> index fe7c05748356..77236f012a1f 100644
> --- a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> +++ b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> @@ -476,6 +476,8 @@ static const struct ropll_config ropll_tmds_cfg[] = {
>  	  1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
>  	{ 650000, 162, 162, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 54, 0, 16, 4, 1,
>  	  1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> +	{ 502500, 84, 84, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 11, 1, 4, 5,
> +	  4, 11, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
>  	{ 337500, 0x70, 0x70, 1, 1, 0xf, 1, 1, 1, 1, 1, 1, 1, 0x2, 0, 0x01, 5,
>  	  1, 1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
>  	{ 400000, 100, 100, 1, 1, 11, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,

With the above fixed,

Reviewed-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>

Thanks,
Cristian

^ permalink raw reply	[flat|nested] 2+ messages in thread

end of thread, other threads:[~2025-04-25  7:13 UTC | newest]

Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
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2025-04-25  2:37 [PATCH] phy: phy-rockchip-samsung-hdptx: Fix PHY PLL output 50.25MHz error Algea Cao
2025-04-25  6:12 ` Cristian Ciocaltea

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