[Intel-gfx] [PATCH v8 21/38] drm/i915/icl: Fetch DSI pkt to be transferred

[Madhav Chauhan]

On 10/30/2018 5:26 PM, Jani Nikula wrote:
> From: Madhav Chauhan <madhav.chauhan at intel.com>
>
> This patch retrieves DSI pkt (from DSI msg)  to be
> sent over DSI link using DRM DSI exported functions.
> A wrapper function is also added as "DSI host transfer"
> for sending DSI data/cmd.
>
> v2 by Jani:
>   - Use the new credit available helper
>   - Use int for free_credits

Changes looks fine, this also has squashing of some of the patches
for sending packet header. That info can be added in "v2 details"

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 | 62 ++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 62 insertions(+)
>
> diff --git a/drivers/gpu/drm/i915/icl_dsi.c b/drivers/gpu/drm/i915/icl_dsi.c
> index d0c60d402dfe..c7b77cd81e45 100644
> --- a/drivers/gpu/drm/i915/icl_dsi.c
> +++ b/drivers/gpu/drm/i915/icl_dsi.c
> @@ -107,6 +107,44 @@ static void wait_for_cmds_dispatched_to_panel(struct intel_encoder *encoder)
>   	}
>   }
>   
> +static int dsi_send_pkt_hdr(struct intel_dsi_host *host,
> +			    struct mipi_dsi_packet pkt, bool enable_lpdt)
> +{
> +	struct intel_dsi *intel_dsi = host->intel_dsi;
> +	struct drm_i915_private *dev_priv = to_i915(intel_dsi->base.base.dev);
> +	enum transcoder dsi_trans = dsi_port_to_transcoder(host->port);
> +	u32 tmp;
> +	int free_credits;
> +
> +	/* check if header credit available */
> +	free_credits = header_credits_available(dev_priv, dsi_trans);
> +	if (free_credits < 1) {
> +		DRM_ERROR("send pkt header failed, not enough hdr credits\n");
> +		return -1;
> +	}
> +
> +	tmp = I915_READ(DSI_CMD_TXHDR(dsi_trans));
> +
> +	if (pkt.payload)
> +		tmp |= PAYLOAD_PRESENT;
> +	else
> +		tmp &= ~PAYLOAD_PRESENT;
> +
> +	tmp &= ~VBLANK_FENCE;
> +
> +	if (enable_lpdt)
> +		tmp |= LP_DATA_TRANSFER;
> +
> +	tmp &= ~(PARAM_WC_MASK | VC_MASK | DT_MASK);
> +	tmp |= ((pkt.header[0] & VC_MASK) << VC_SHIFT);
> +	tmp |= ((pkt.header[0] & DT_MASK) << DT_SHIFT);
> +	tmp |= (pkt.header[1] << PARAM_WC_LOWER_SHIFT);
> +	tmp |= (pkt.header[2] << PARAM_WC_UPPER_SHIFT);
> +	I915_WRITE(DSI_CMD_TXHDR(dsi_trans), tmp);
> +
> +	return 0;
> +}
> +
>   static void dsi_program_swing_and_deemphasis(struct intel_encoder *encoder)
>   {
>   	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> @@ -994,9 +1032,33 @@ static int gen11_dsi_host_detach(struct mipi_dsi_host *host,
>   	return 0;
>   }
>   
> +static ssize_t gen11_dsi_host_transfer(struct mipi_dsi_host *host,
> +				       const struct mipi_dsi_msg *msg)
> +{
> +	struct intel_dsi_host *intel_dsi_host = to_intel_dsi_host(host);
> +	struct mipi_dsi_packet dsi_pkt;
> +	ssize_t ret;
> +	bool enable_lpdt = false;
> +
> +	ret = mipi_dsi_create_packet(&dsi_pkt, msg);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (msg->flags & MIPI_DSI_MSG_USE_LPM)
> +		enable_lpdt = true;
> +
> +	/* send packet header */
> +	ret  = dsi_send_pkt_hdr(intel_dsi_host, dsi_pkt, enable_lpdt);
> +	if (ret < 0)
> +		return ret;
> +
> +	return ret;
> +}
> +
>   static const struct mipi_dsi_host_ops gen11_dsi_host_ops = {
>   	.attach = gen11_dsi_host_attach,
>   	.detach = gen11_dsi_host_detach,
> +	.transfer = gen11_dsi_host_transfer,
>   };
>   
>   void icl_dsi_init(struct drm_i915_private *dev_priv)