Re: [RESEND PATCH v3 5/6] drm/ingenic: Upload palette before frame

[Christophe Branchereau <cbranchereau@gmail.com>]

Reviewed-by: Christophe Branchereau <cbranchereau@gmail.com>

On Tue, Oct 26, 2021 at 8:13 PM Paul Cercueil <paul@crapouillou.net> wrote:
>
> When using C8 color mode, make sure that the palette is always uploaded
> before a frame; otherwise the very first frame will have wrong colors.
>
> Do that by changing the link order of the DMA descriptors.
>
> v3: Fix ingenic_drm_get_new_priv_state() called instead of
>     ingenic_drm_get_priv_state()
>
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> ---
>  drivers/gpu/drm/ingenic/ingenic-drm-drv.c | 53 ++++++++++++++++++++---
>  1 file changed, 47 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
> index cbc76cede99e..a5e2880e07a1 100644
> --- a/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
> +++ b/drivers/gpu/drm/ingenic/ingenic-drm-drv.c
> @@ -66,6 +66,7 @@ struct jz_soc_info {
>
>  struct ingenic_drm_private_state {
>         struct drm_private_state base;
> +       bool use_palette;
>  };
>
>  struct ingenic_drm {
> @@ -113,6 +114,30 @@ to_ingenic_drm_priv_state(struct drm_private_state *state)
>         return container_of(state, struct ingenic_drm_private_state, base);
>  }
>
> +static struct ingenic_drm_private_state *
> +ingenic_drm_get_priv_state(struct ingenic_drm *priv, struct drm_atomic_state *state)
> +{
> +       struct drm_private_state *priv_state;
> +
> +       priv_state = drm_atomic_get_private_obj_state(state, &priv->private_obj);
> +       if (IS_ERR(priv_state))
> +               return ERR_CAST(priv_state);
> +
> +       return to_ingenic_drm_priv_state(priv_state);
> +}
> +
> +static struct ingenic_drm_private_state *
> +ingenic_drm_get_new_priv_state(struct ingenic_drm *priv, struct drm_atomic_state *state)
> +{
> +       struct drm_private_state *priv_state;
> +
> +       priv_state = drm_atomic_get_new_private_obj_state(state, &priv->private_obj);
> +       if (!priv_state)
> +               return NULL;
> +
> +       return to_ingenic_drm_priv_state(priv_state);
> +}
> +
>  static bool ingenic_drm_writeable_reg(struct device *dev, unsigned int reg)
>  {
>         switch (reg) {
> @@ -183,11 +208,18 @@ static void ingenic_drm_crtc_atomic_enable(struct drm_crtc *crtc,
>                                            struct drm_atomic_state *state)
>  {
>         struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
> +       struct ingenic_drm_private_state *priv_state;
> +       unsigned int next_id;
> +
> +       priv_state = ingenic_drm_get_priv_state(priv, state);
> +       if (WARN_ON(IS_ERR(priv_state)))
> +               return;
>
>         regmap_write(priv->map, JZ_REG_LCD_STATE, 0);
>
> -       /* Set address of our DMA descriptor chain */
> -       regmap_write(priv->map, JZ_REG_LCD_DA0, dma_hwdesc_addr(priv, 0));
> +       /* Set addresses of our DMA descriptor chains */
> +       next_id = priv_state->use_palette ? HWDESC_PALETTE : 0;
> +       regmap_write(priv->map, JZ_REG_LCD_DA0, dma_hwdesc_addr(priv, next_id));
>         regmap_write(priv->map, JZ_REG_LCD_DA1, dma_hwdesc_addr(priv, 1));
>
>         regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
> @@ -393,6 +425,7 @@ static int ingenic_drm_plane_atomic_check(struct drm_plane *plane,
>         struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state,
>                                                                                  plane);
>         struct ingenic_drm *priv = drm_device_get_priv(plane->dev);
> +       struct ingenic_drm_private_state *priv_state;
>         struct drm_crtc_state *crtc_state;
>         struct drm_crtc *crtc = new_plane_state->crtc ?: old_plane_state->crtc;
>         int ret;
> @@ -405,6 +438,10 @@ static int ingenic_drm_plane_atomic_check(struct drm_plane *plane,
>         if (WARN_ON(!crtc_state))
>                 return -EINVAL;
>
> +       priv_state = ingenic_drm_get_priv_state(priv, state);
> +       if (IS_ERR(priv_state))
> +               return PTR_ERR(priv_state);
> +
>         ret = drm_atomic_helper_check_plane_state(new_plane_state, crtc_state,
>                                                   DRM_PLANE_HELPER_NO_SCALING,
>                                                   DRM_PLANE_HELPER_NO_SCALING,
> @@ -423,6 +460,9 @@ static int ingenic_drm_plane_atomic_check(struct drm_plane *plane,
>              (new_plane_state->src_h >> 16) != new_plane_state->crtc_h))
>                 return -EINVAL;
>
> +       priv_state->use_palette = new_plane_state->fb &&
> +               new_plane_state->fb->format->format == DRM_FORMAT_C8;
> +
>         /*
>          * Require full modeset if enabling or disabling a plane, or changing
>          * its position, size or depth.
> @@ -583,6 +623,7 @@ static void ingenic_drm_plane_atomic_update(struct drm_plane *plane,
>         struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state, plane);
>         struct drm_plane_state *oldstate = drm_atomic_get_old_plane_state(state, plane);
>         unsigned int width, height, cpp, next_id, plane_id;
> +       struct ingenic_drm_private_state *priv_state;
>         struct drm_crtc_state *crtc_state;
>         struct ingenic_dma_hwdesc *hwdesc;
>         dma_addr_t addr;
> @@ -600,19 +641,19 @@ static void ingenic_drm_plane_atomic_update(struct drm_plane *plane,
>                 height = newstate->src_h >> 16;
>                 cpp = newstate->fb->format->cpp[0];
>
> -               hwdesc = &priv->dma_hwdescs->hwdesc[plane_id];
> +               priv_state = ingenic_drm_get_new_priv_state(priv, state);
> +               next_id = (priv_state && priv_state->use_palette) ? HWDESC_PALETTE : plane_id;
>
> +               hwdesc = &priv->dma_hwdescs->hwdesc[plane_id];
>                 hwdesc->addr = addr;
>                 hwdesc->cmd = JZ_LCD_CMD_EOF_IRQ | (width * height * cpp / 4);
> +               hwdesc->next = dma_hwdesc_addr(priv, next_id);
>
>                 if (drm_atomic_crtc_needs_modeset(crtc_state)) {
>                         fourcc = newstate->fb->format->format;
>
>                         ingenic_drm_plane_config(priv->dev, plane, fourcc);
>
> -                       next_id = fourcc == DRM_FORMAT_C8 ? HWDESC_PALETTE : 0;
> -                       priv->dma_hwdescs->hwdesc[0].next = dma_hwdesc_addr(priv, next_id);
> -
>                         crtc_state->color_mgmt_changed = fourcc == DRM_FORMAT_C8;
>                 }
>
> --
> 2.33.0
>