Am Freitag, dem 11.03.2022 um 18:05 +0100 schrieb Marek Vasut:
> Wrap FIFO reset and comments into mxsfb_reset_block(), this is a clean up.
> No functional change.
>
> Signed-off-by: Marek Vasut <marex@xxxxxxx>
> Cc: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx>
> Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> Cc: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> Cc: Peng Fan <peng.fan@xxxxxxx>
> Cc: Robby Cai <robby.cai@xxxxxxx>
> Cc: Sam Ravnborg <sam@xxxxxxxxxxxx>
> Cc: Stefan Agner <stefan@xxxxxxxx>
Reviewed-by: Lucas Stach <l.stach@xxxxxxxxxxxxxx>
> ---
> V2: No change
> ---
> drivers/gpu/drm/mxsfb/mxsfb_kms.c | 36 +++++++++++++++++--------------
> 1 file changed, 20 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpu/drm/mxsfb/mxsfb_kms.c b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> index 657b6afbbf1f9..015b289d93a3c 100644
> --- a/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> +++ b/drivers/gpu/drm/mxsfb/mxsfb_kms.c
> @@ -183,6 +183,12 @@ static int mxsfb_reset_block(struct mxsfb_drm_private *mxsfb)
> {
> int ret;
>
> + /*
> + * It seems, you can't re-program the controller if it is still
> + * running. This may lead to shifted pictures (FIFO issue?), so
> + * first stop the controller and drain its FIFOs.
> + */
> +
> ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_SFTRST);
> if (ret)
> return ret;
> @@ -193,7 +199,20 @@ static int mxsfb_reset_block(struct mxsfb_drm_private *mxsfb)
> if (ret)
> return ret;
>
> - return clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_CLKGATE);
> + ret = clear_poll_bit(mxsfb->base + LCDC_CTRL, CTRL_CLKGATE);
> + if (ret)
> + return ret;
> +
> + /* Clear the FIFOs */
> + writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
> + readl(mxsfb->base + LCDC_CTRL1);
> + writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_CLR);
> + readl(mxsfb->base + LCDC_CTRL1);
> +
> + if (mxsfb->devdata->has_overlay)
> + writel(0, mxsfb->base + LCDC_AS_CTRL);
> +
> + return 0;
> }
>
> static dma_addr_t mxsfb_get_fb_paddr(struct drm_plane *plane)
> @@ -220,26 +239,11 @@ static void mxsfb_crtc_mode_set_nofb(struct mxsfb_drm_private *mxsfb,
> u32 vdctrl0, vsync_pulse_len, hsync_pulse_len;
> int err;
>
> - /*
> - * It seems, you can't re-program the controller if it is still
> - * running. This may lead to shifted pictures (FIFO issue?), so
> - * first stop the controller and drain its FIFOs.
> - */
> -
> /* Mandatory eLCDIF reset as per the Reference Manual */
> err = mxsfb_reset_block(mxsfb);
> if (err)
> return;
>
> - /* Clear the FIFOs */
> - writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_SET);
> - readl(mxsfb->base + LCDC_CTRL1);
> - writel(CTRL1_FIFO_CLEAR, mxsfb->base + LCDC_CTRL1 + REG_CLR);
> - readl(mxsfb->base + LCDC_CTRL1);
> -
> - if (mxsfb->devdata->has_overlay)
> - writel(0, mxsfb->base + LCDC_AS_CTRL);
> -
> mxsfb_set_formats(mxsfb, bus_format);
>
> if (mxsfb->bridge && mxsfb->bridge->timings)
