Re: [PATCH v4 76/80] drm/omap: dsi: cleanup initial vc setup

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Tomi,

Thank you for the patch.

On Tue, Nov 24, 2020 at 02:45:34PM +0200, Tomi Valkeinen wrote:
> As we now have a fixed setup for VCs (VC0 for video stream, VC1 for
> commands), we can simplify the VC setup.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
> ---
>  drivers/gpu/drm/omapdrm/dss/dsi.c | 85 +++++++++++--------------------
>  1 file changed, 31 insertions(+), 54 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c b/drivers/gpu/drm/omapdrm/dss/dsi.c
> index ff8ace957291..27d0d119668b 100644
> --- a/drivers/gpu/drm/omapdrm/dss/dsi.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dsi.c
> @@ -2017,40 +2017,6 @@ static void dsi_vc_initial_config(struct dsi_data *dsi, int vc)
>  	dsi->vc[vc].source = DSI_VC_SOURCE_L4;
>  }
>  
> -static int dsi_vc_config_source(struct dsi_data *dsi, int vc,
> -				enum dsi_vc_source source)
> -{
> -	if (dsi->vc[vc].source == source)
> -		return 0;
> -
> -	DSSDBG("Source config of VC %d", vc);
> -
> -	dsi_sync_vc(dsi, vc);
> -
> -	dsi_vc_enable(dsi, vc, 0);
> -
> -	/* VC_BUSY */
> -	if (!wait_for_bit_change(dsi, DSI_VC_CTRL(vc), 15, 0)) {
> -		DSSERR("vc(%d) busy when trying to config for VP\n", vc);
> -		return -EIO;
> -	}
> -
> -	/* SOURCE, 0 = L4, 1 = video port */
> -	REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), source, 1, 1);
> -
> -	/* DCS_CMD_ENABLE */
> -	if (dsi->data->quirks & DSI_QUIRK_DCS_CMD_CONFIG_VC) {
> -		bool enable = source == DSI_VC_SOURCE_VP;
> -		REG_FLD_MOD(dsi, DSI_VC_CTRL(vc), enable, 30, 30);
> -	}
> -
> -	dsi_vc_enable(dsi, vc, 1);
> -
> -	dsi->vc[vc].source = source;
> -
> -	return 0;
> -}
> -
>  static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc,
>  		bool enable)
>  {
> @@ -2072,10 +2038,6 @@ static void dsi_vc_enable_hs(struct omap_dss_device *dssdev, int vc,
>  	dsi_if_enable(dsi, 1);
>  
>  	dsi_force_tx_stop_mode_io(dsi);
> -
> -	/* start the DDR clock by sending a NULL packet */
> -	if (dsi->vm_timings.ddr_clk_always_on && enable)
> -		dsi_vc_send_null(dsi, vc, dsi->dsidev->channel);
>  }
>  
>  static void dsi_vc_flush_long_data(struct dsi_data *dsi, int vc)
> @@ -2270,8 +2232,6 @@ static int dsi_vc_send_long(struct dsi_data *dsi, int vc,
>  		return -EINVAL;
>  	}
>  
> -	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_L4);
> -
>  	dsi_vc_write_long_header(dsi, vc, msg->channel, msg->type, msg->tx_len, 0);
>  
>  	p = msg->tx_buf;
> @@ -2331,8 +2291,6 @@ static int dsi_vc_send_short(struct dsi_data *dsi, int vc,
>  		DSSDBG("dsi_vc_send_short(ch%d, dt %#x, b1 %#x, b2 %#x)\n",
>  		       vc, msg->type, pkt.header[1], pkt.header[2]);
>  
> -	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_L4);
> -
>  	if (FLD_GET(dsi_read_reg(dsi, DSI_VC_CTRL(vc)), 16, 16)) {
>  		DSSERR("ERROR FIFO FULL, aborting transfer\n");
>  		return -EINVAL;
> @@ -3351,8 +3309,6 @@ static void dsi_update_screen_dispc(struct dsi_data *dsi)
>  
>  	DSSDBG("dsi_update_screen_dispc(%dx%d)\n", w, h);
>  
> -	dsi_vc_config_source(dsi, vc, DSI_VC_SOURCE_VP);
> -
>  	bytespp	= mipi_dsi_pixel_format_to_bpp(dsi->pix_fmt) / 8;
>  	bytespl = w * bytespp;
>  	bytespf = bytespl * h;
> @@ -3522,9 +3478,7 @@ static int dsi_update_channel(struct omap_dss_device *dssdev, int vc)
>  
>  	dsi_set_ulps_auto(dsi, false);
>  
> -	dsi_vc_enable_hs(dssdev, vc, !(dsi->dsidev->mode_flags & MIPI_DSI_MODE_LPM));

Why is this not needed anymore ?

> -
> -	r = _dsi_send_nop(dsi, vc, dsi->dsidev->channel);
> +	r = _dsi_send_nop(dsi, VC_CMD, dsi->dsidev->channel);
>  	if (r < 0) {
>  		DSSWARN("failed to send nop between frames: %d\n", r);
>  		goto err;
> @@ -3649,6 +3603,35 @@ static int dsi_configure_dsi_clocks(struct dsi_data *dsi)
>  	return 0;
>  }
>  
> +static void dsi_setup_dsi_vcs(struct dsi_data *dsi)
> +{
> +	/* Setup VC_CMD for LP and cpu transfers */
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(VC_CMD), 0, 9, 9); /* LP */
> +
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(VC_CMD), 0, 1, 1); /* SOURCE_L4 */
> +	dsi->vc[VC_CMD].source = DSI_VC_SOURCE_L4;
> +
> +	/* Setup VC_VIDEO for HS and dispc transfers */
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(VC_VIDEO), 1, 9, 9); /* HS */
> +
> +	REG_FLD_MOD(dsi, DSI_VC_CTRL(VC_VIDEO), 1, 1, 1); /* SOURCE_VP */
> +	dsi->vc[VC_VIDEO].source = DSI_VC_SOURCE_VP;
> +
> +	if (dsi->data->quirks & DSI_QUIRK_DCS_CMD_CONFIG_VC)
> +		REG_FLD_MOD(dsi, DSI_VC_CTRL(VC_VIDEO), 1, 30, 30); /* DCS_CMD_ENABLE */
> +
> +	dsi_vc_enable(dsi, VC_CMD, 1);
> +	dsi_vc_enable(dsi, VC_VIDEO, 1);
> +
> +	dsi_if_enable(dsi, 1);
> +
> +	dsi_force_tx_stop_mode_io(dsi);
> +
> +	/* start the DDR clock by sending a NULL packet */
> +	if (dsi->vm_timings.ddr_clk_always_on)
> +		dsi_vc_send_null(dsi, VC_CMD, dsi->dsidev->channel);
> +}
> +
>  static int dsi_init_dsi(struct dsi_data *dsi)
>  {
>  	int r;
> @@ -3691,13 +3674,7 @@ static int dsi_init_dsi(struct dsi_data *dsi)
>  	if (r)
>  		goto err3;
>  
> -	/* enable interface */
> -	dsi_vc_enable(dsi, 0, 1);
> -	dsi_vc_enable(dsi, 1, 1);
> -	dsi_vc_enable(dsi, 2, 1);
> -	dsi_vc_enable(dsi, 3, 1);
> -	dsi_if_enable(dsi, 1);
> -	dsi_force_tx_stop_mode_io(dsi);
> +	dsi_setup_dsi_vcs(dsi);
>  
>  	return 0;
>  err3:

-- 
Regards,

Laurent Pinchart