[Intel-gfx] [PATCH v8 03/38] drm/i915/icl: Set max return packet size for DSI panel

[Madhav Chauhan]

On 10/30/2018 5:26 PM, Jani Nikula wrote:
> From: Madhav Chauhan <madhav.chauhan at intel.com>
>
> This patch programs maximum size of the payload transmitted
> from peripheral back to the host processor using short packet
> as a part of panel programming.
>
> v2: Rebase
>
> v3 by Jani:
>   - Add FIXME note.

Looks OK to me.

Regards,
Madhav

>
> Signed-off-by: Madhav Chauhan <madhav.chauhan at intel.com>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> ---
>   drivers/gpu/drm/i915/icl_dsi.c | 33 +++++++++++++++++++++++++++++++++
>   1 file changed, 33 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/icl_dsi.c b/drivers/gpu/drm/i915/icl_dsi.c
> index 216a1753d246..9c424adc8b75 100644
> --- a/drivers/gpu/drm/i915/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/icl_dsi.c
> @@ -25,6 +25,7 @@
>    *   Jani Nikula <jani.nikula at intel.com>
>    */
>   
> +#include <drm/drm_mipi_dsi.h>
>   #include "intel_dsi.h"
>   
>   static enum transcoder dsi_port_to_transcoder(enum port port)
> @@ -636,6 +637,35 @@ gen11_dsi_enable_port_and_phy(struct intel_encoder *encoder,
>   	gen11_dsi_configure_transcoder(encoder, pipe_config);
>   }
>   
> +static void gen11_dsi_powerup_panel(struct intel_encoder *encoder)
> +{
> +	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> +	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
> +	struct mipi_dsi_device *dsi;
> +	enum port port;
> +	enum transcoder dsi_trans;
> +	u32 tmp;
> +	int ret;
> +
> +	/* set maximum return packet size */
> +	for_each_dsi_port(port, intel_dsi->ports) {
> +		dsi_trans = dsi_port_to_transcoder(port);
> +
> +		/*
> +		 * FIXME: This uses the number of DW's currently in the payload
> +		 * receive queue. This is probably not what we want here.
> +		 */
> +		tmp = I915_READ(DSI_CMD_RXCTL(dsi_trans));
> +		tmp &= NUMBER_RX_PLOAD_DW_MASK;
> +		/* multiply "Number Rx Payload DW" by 4 to get max value */
> +		tmp = tmp * 4;
> +		dsi = intel_dsi->dsi_hosts[port]->device;
> +		ret = mipi_dsi_set_maximum_return_packet_size(dsi, tmp);
> +		if (ret < 0)
> +			DRM_ERROR("error setting max return pkt size%d\n", tmp);
> +	}
> +}
> +
>   static void __attribute__((unused))
>   gen11_dsi_pre_enable(struct intel_encoder *encoder,
>   		     const struct intel_crtc_state *pipe_config,
> @@ -650,6 +680,9 @@ gen11_dsi_pre_enable(struct intel_encoder *encoder,
>   	/* step4: enable DSI port and DPHY */
>   	gen11_dsi_enable_port_and_phy(encoder, pipe_config);
>   
> +	/* step5: program and powerup panel */
> +	gen11_dsi_powerup_panel(encoder);
> +
>   	/* step6c: configure transcoder timings */
>   	gen11_dsi_set_transcoder_timings(encoder, pipe_config);
>