[PATCH 09/10] drm/exynos/hdmi: quirk for support mode timings conversion

[Tobias Jakobi]

Hello Andrzej,


Andrzej Hajda wrote:
> MIXER in SoCs prior to Exynos5420 supports only 4 video modes:
> 720x480, 720x576, 1280x720, 1920x1080. Support for other modes
> can be enabled by manipulating timings of HDMI. To do it
> adjusted_mode should contain actual mode set on crtc.
> With this patch it is possible to enable 1024x768 and 1280x1024
> modes in MIXER.

Reviewed-by: Tobias Jakobi <tjakobi at math.uni-bielefeld.de>

And some question below.


> Suggested-by: Daniel Drake <drake at endlessm.com>
> Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
> ---
>  drivers/gpu/drm/exynos/exynos_hdmi.c | 15 +++++++++++++--
>  1 file changed, 13 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
> index 7225b65..4b081f6 100644
> --- a/drivers/gpu/drm/exynos/exynos_hdmi.c
> +++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
> @@ -1239,6 +1239,17 @@ static void hdmi_v13_mode_apply(struct hdmi_context *hdata)
>  static void hdmi_v14_mode_apply(struct hdmi_context *hdata)
>  {
>  	struct drm_display_mode *m = &hdata->encoder.crtc->state->mode;
> +	struct drm_display_mode *am = &hdata->encoder.crtc->state->adjusted_mode;
> +	int hquirk = 0;
> +
> +	/*
> +	 * In case video mode coming from CRTC differs from requested one HDMI
> +	 * sometimes is able to almost properly perform conversion - only
> +	 * first line is distorted.
> +	 */
> +	if ((m->vdisplay != am->vdisplay) &&
> +	    (m->hdisplay == 1280 || m->hdisplay == 1024))
> +		hquirk = 258;
Can it even happen, that m->hdisplay is neither 1280 nor 1024 but "m->vdisplay
!= am->vdisplay" still holds?



>  	hdmi_reg_writev(hdata, HDMI_H_BLANK_0, 2, m->htotal - m->hdisplay);
>  	hdmi_reg_writev(hdata, HDMI_V_LINE_0, 2, m->vtotal);
> @@ -1332,8 +1343,8 @@ static void hdmi_v14_mode_apply(struct hdmi_context *hdata)
>  	hdmi_reg_writev(hdata, HDMI_V_SYNC_LINE_AFT_PXL_6_0, 2, 0xffff);
>  
>  	hdmi_reg_writev(hdata, HDMI_TG_H_FSZ_L, 2, m->htotal);
> -	hdmi_reg_writev(hdata, HDMI_TG_HACT_ST_L, 2, m->htotal - m->hdisplay);
> -	hdmi_reg_writev(hdata, HDMI_TG_HACT_SZ_L, 2, m->hdisplay);
> +	hdmi_reg_writev(hdata, HDMI_TG_HACT_ST_L, 2, m->htotal - m->hdisplay - hquirk);
> +	hdmi_reg_writev(hdata, HDMI_TG_HACT_SZ_L, 2, m->hdisplay + hquirk);
>  	hdmi_reg_writev(hdata, HDMI_TG_V_FSZ_L, 2, m->vtotal);
>  	if (hdata->drv_data == &exynos5433_hdmi_driver_data)
>  		hdmi_reg_writeb(hdata, HDMI_TG_DECON_EN, 1);
>