Re: [PATCH v10 12/24] drm/rockchip: dw_hdmi: drop mode_valid hook

[Alex Bee <knaerzche@gmail.com>]

Am 08.04.22 um 13:22 schrieb Sascha Hauer:
> The driver checks if the pixel clock of the given mode matches an entry
> in the mpll config table. The frequencies in the mpll table are meant as
> a frequency range up to which the entry works, not as a frequency that
> must match the pixel clock. The downstream Kernel also does not have
> this check, so drop it to allow for more display resolutions.
> 
> Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
> ---
> 
You're correct: That frequency is meant to be greater or equal. But I'm
not sure if it makes sense to completely drop it - what happens for
clocks rates > 600 MHz which might be supported by later generation
sinks (HDMI 2.1 or later)?
As these are not supported by the IPs/PHYs currently supported by that
driver a reason a simple

        int i;



        for (i = 0; mpll_cfg[i].mpixelclock != (~0UL); i++) {

-               if (pclk == mpll_cfg[i].mpixelclock) {

+               if (pclk >= mpll_cfg[i].mpixelclock) {

                        valid = true;

                        break;

                }

would be the better idea, I guess.

Regards,
Alex

> Notes:
>     Changes since v3:
>     - new patch
> 
>  drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c | 25 ---------------------
>  1 file changed, 25 deletions(-)
> 
> diff --git a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
> index cb43e7b47157d..008ab20f39ee6 100644
> --- a/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
> +++ b/drivers/gpu/drm/rockchip/dw_hdmi-rockchip.c
> @@ -248,26 +248,6 @@ static int rockchip_hdmi_parse_dt(struct rockchip_hdmi *hdmi)
>  	return 0;
>  }
>  
> -static enum drm_mode_status
> -dw_hdmi_rockchip_mode_valid(struct dw_hdmi *hdmi, void *data,
> -			    const struct drm_display_info *info,
> -			    const struct drm_display_mode *mode)
> -{
> -	const struct dw_hdmi_mpll_config *mpll_cfg = rockchip_mpll_cfg;
> -	int pclk = mode->clock * 1000;
> -	bool valid = false;
> -	int i;
> -
> -	for (i = 0; mpll_cfg[i].mpixelclock != (~0UL); i++) {
> -		if (pclk == mpll_cfg[i].mpixelclock) {
> -			valid = true;
> -			break;
> -		}
> -	}
> -
> -	return (valid) ? MODE_OK : MODE_BAD;
> -}
> -
>  static void dw_hdmi_rockchip_encoder_disable(struct drm_encoder *encoder)
>  {
>  }
> @@ -433,7 +413,6 @@ static struct rockchip_hdmi_chip_data rk3228_chip_data = {
>  };
>  
>  static const struct dw_hdmi_plat_data rk3228_hdmi_drv_data = {
> -	.mode_valid = dw_hdmi_rockchip_mode_valid,
>  	.mpll_cfg = rockchip_mpll_cfg,
>  	.cur_ctr = rockchip_cur_ctr,
>  	.phy_config = rockchip_phy_config,
> @@ -450,7 +429,6 @@ static struct rockchip_hdmi_chip_data rk3288_chip_data = {
>  };
>  
>  static const struct dw_hdmi_plat_data rk3288_hdmi_drv_data = {
> -	.mode_valid = dw_hdmi_rockchip_mode_valid,
>  	.mpll_cfg   = rockchip_mpll_cfg,
>  	.cur_ctr    = rockchip_cur_ctr,
>  	.phy_config = rockchip_phy_config,
> @@ -470,7 +448,6 @@ static struct rockchip_hdmi_chip_data rk3328_chip_data = {
>  };
>  
>  static const struct dw_hdmi_plat_data rk3328_hdmi_drv_data = {
> -	.mode_valid = dw_hdmi_rockchip_mode_valid,
>  	.mpll_cfg = rockchip_mpll_cfg,
>  	.cur_ctr = rockchip_cur_ctr,
>  	.phy_config = rockchip_phy_config,
> @@ -488,7 +465,6 @@ static struct rockchip_hdmi_chip_data rk3399_chip_data = {
>  };
>  
>  static const struct dw_hdmi_plat_data rk3399_hdmi_drv_data = {
> -	.mode_valid = dw_hdmi_rockchip_mode_valid,
>  	.mpll_cfg   = rockchip_mpll_cfg,
>  	.cur_ctr    = rockchip_cur_ctr,
>  	.phy_config = rockchip_phy_config,
> @@ -501,7 +477,6 @@ static struct rockchip_hdmi_chip_data rk3568_chip_data = {
>  };
>  
>  static const struct dw_hdmi_plat_data rk3568_hdmi_drv_data = {
> -	.mode_valid = dw_hdmi_rockchip_mode_valid,
>  	.mpll_cfg   = rockchip_mpll_cfg,
>  	.cur_ctr    = rockchip_cur_ctr,
>  	.phy_config = rockchip_phy_config,