[PATCH v2] rockchip/drm: vop2: add support for gamma LUT

[Piotr Zalewski]

By mistake the incremental patch were sent here. The correct v2 patch was
sent in the form of a v3 patch [1]

[1] https://lore.kernel.org/linux-rockchip/TkgKVivuaLFLILPY-n3iZo_8KF-daKdqdu-0_e0HP-5Ar_8DALDeNWog2suwWKjX7eomcbGET0KZe7DlzdhK2YM6CbLbeKeFZr-MJzJMtw0=@proton.me/T/#u

On Wednesday, July 24th, 2024 at 9:06 PM, Piotr Zalewski <pZ010001011111 at proton.me> wrote:

> Add support for gamma LUT in VOP2 driver. The implementation is based on
> the one found in VOP driver and modified to be compatible with VOP2. Blue
> and red channels in gamma LUT register write were swapped with respect to
> how gamma LUT values are written in VOP. Write of the current video port id
> to VOP2_SYS_LUT_PORT_SEL register was added before the write of DSP_LUT_EN
> bit. Gamma size is set and drm color management is enabled for each video
> port's CRTC except ones which have no associated device. Tested on RK3566
> (Pinetab2).
> 
> Helped-by: Dragan Simic dsimic at manjaro.org
> 
> Signed-off-by: Piotr Zalewski pZ010001011111 at proton.me
> 
> ---
> 
> Notes:
> Changes in v2:
> - Apply code styling corrections [1]
> - Move gamma LUT write inside the vop2 lock
> 
> Link to v1: https://lore.kernel.org/linux-rockchip/9736eadf6a9d8e97eef919c6b3d88828@manjaro.org/T/#t
> 
> [1] https://lore.kernel.org/linux-rockchip/d019761504b540600d9fc7a585d6f95f@manjaro.org/
> 
> diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> index 16abdc4a59a8..37fcf544a5fd 100644
> --- a/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> +++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop2.c
> @@ -1515,9 +1515,8 @@ static void vop2_vp_dsp_lut_disable(struct vop2_video_port *vp)
> 
> static void vop2_crtc_write_gamma_lut(struct vop2 *vop2, struct drm_crtc *crtc)
> {
> - const struct vop2_data *vop2_data = vop2->data;
> 
> const struct vop2_video_port *vp = to_vop2_video_port(crtc);
> - const struct vop2_video_port_data *vp_data = &vop2_data->vp[vp->id];
> 
> + const struct vop2_video_port_data *vp_data = &vop2->data->vp[vp->id];
> 
> 
> struct drm_color_lut *lut = crtc->state->gamma_lut->data;
> 
> unsigned int i, bpc = ilog2(vp_data->gamma_lut_len);
> 
> @@ -1558,9 +1557,8 @@ static void vop2_crtc_gamma_set(struct vop2 *vop2, struct drm_crtc *crtc,
> * In order to write the LUT to the internal memory,
> * we need to first make sure the dsp_lut_en bit is cleared.
> */
> - ret =
> - readx_poll_timeout(vop2_vp_dsp_lut_is_enabled, vp, dsp_ctrl, !dsp_ctrl, 5,
> - 30 * 1000);
> + ret = readx_poll_timeout(vop2_vp_dsp_lut_is_enabled, vp, dsp_ctrl,
> + !dsp_ctrl, 5, 30 * 1000);
> 
> if (ret) {
> DRM_DEV_ERROR(vop2->dev, "display LUT RAM enable timeout!\n");
> 
> @@ -1571,9 +1569,9 @@ static void vop2_crtc_gamma_set(struct vop2 *vop2, struct drm_crtc *crtc,
> return;
> }
> 
> - vop2_crtc_write_gamma_lut(vop2, crtc);
> 
> vop2_lock(vop2);
> + vop2_crtc_write_gamma_lut(vop2, crtc);
> vop2_writel(vp->vop2, RK3568_LUT_PORT_SEL, vp->id);
> 
> 
> vop2_vp_dsp_lut_enable(vp);