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

[Jani Nikula]

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

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)
-- 
2.11.0