Commit 43315f86 authored by Lee Shawn C's avatar Lee Shawn C Committed by Vandita Kulkarni
Browse files

drm/i915/dsi: wait for header and payload credit available 



Driver should wait for free header or payload buffer in FIFO.
It would be good to wait a while for HW to release credit before
give it up to write to HW. Without sending initailize command
sets completely. It would caused MIPI display can't light up properly.

Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Vandita Kulkarni <vandita.kulkarni@intel.com>
Cc: Cooper Chiou <cooper.chiou@intel.com>
Cc: William Tseng <william.tseng@intel.com>
Signed-off-by: default avatarLee Shawn C <shawn.c.lee@intel.com>
Reviewed-by: default avatarVandita Kulkarni <vandita.kulkarni@intel.com>
Signed-off-by: default avatarVandita Kulkarni <vandita.kulkarni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210908115607.9633-2-shawn.c.lee@intel.com
parent 0f3692b5

drivers/gpu/drm/i915/display/icl_dsi.c

+19 −21
Original line number Diff line number Diff line
@@ -55,20 +55,28 @@ static int payload_credits_available(struct drm_i915_private *dev_priv, 
		>> FREE_PLOAD_CREDIT_SHIFT;

}



static void wait_for_header_credits(struct drm_i915_private *dev_priv,

				    enum transcoder dsi_trans)

static bool wait_for_header_credits(struct drm_i915_private *dev_priv,

				    enum transcoder dsi_trans, int hdr_credit)

{

	if (wait_for_us(header_credits_available(dev_priv, dsi_trans) >=

			MAX_HEADER_CREDIT, 100))

			hdr_credit, 100)) {

		drm_err(&dev_priv->drm, "DSI header credits not released\n");

		return false;

	}



static void wait_for_payload_credits(struct drm_i915_private *dev_priv,

				     enum transcoder dsi_trans)

	return true;

}



static bool wait_for_payload_credits(struct drm_i915_private *dev_priv,

				     enum transcoder dsi_trans, int payld_credit)

{

	if (wait_for_us(payload_credits_available(dev_priv, dsi_trans) >=

			MAX_PLOAD_CREDIT, 100))

			payld_credit, 100)) {

		drm_err(&dev_priv->drm, "DSI payload credits not released\n");

		return false;

	}



	return true;

}



static enum transcoder dsi_port_to_transcoder(enum port port)
@@ -91,8 +99,8 @@ static void wait_for_cmds_dispatched_to_panel(struct intel_encoder *encoder) 
	/* wait for header/payload credits to be released */

	for_each_dsi_port(port, intel_dsi->ports) {

		dsi_trans = dsi_port_to_transcoder(port);

		wait_for_header_credits(dev_priv, dsi_trans);

		wait_for_payload_credits(dev_priv, dsi_trans);

		wait_for_header_credits(dev_priv, dsi_trans, MAX_HEADER_CREDIT);

		wait_for_payload_credits(dev_priv, dsi_trans, MAX_PLOAD_CREDIT);

	}



	/* send nop DCS command */
@@ -109,7 +117,7 @@ static void wait_for_cmds_dispatched_to_panel(struct intel_encoder *encoder) 
	/* wait for header credits to be released */

	for_each_dsi_port(port, intel_dsi->ports) {

		dsi_trans = dsi_port_to_transcoder(port);

		wait_for_header_credits(dev_priv, dsi_trans);

		wait_for_header_credits(dev_priv, dsi_trans, MAX_HEADER_CREDIT);

	}



	/* wait for LP TX in progress bit to be cleared */
@@ -127,18 +135,13 @@ static bool add_payld_to_queue(struct intel_dsi_host *host, const u8 *data, 
	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);

	int free_credits;

	int i, j;



	for (i = 0; i < len; i += 4) {

		u32 tmp = 0;



		free_credits = payload_credits_available(dev_priv, dsi_trans);

		if (free_credits < 1) {

			drm_err(&dev_priv->drm,

				"Payload credit not available\n");

		if (!wait_for_payload_credits(dev_priv, dsi_trans, 1))

			return false;

		}



		for (j = 0; j < min_t(u32, len - i, 4); j++)

			tmp |= *data++ << 8 * j;
@@ -156,15 +159,10 @@ static int dsi_send_pkt_hdr(struct intel_dsi_host *host, 
	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_err(&dev_priv->drm,

			"send pkt header failed, not enough hdr credits\n");

	if (!wait_for_header_credits(dev_priv, dsi_trans, 1))

		return -1;

	}



	tmp = intel_de_read(dev_priv, DSI_CMD_TXHDR(dsi_trans));