From 43315f86a3a59255463d14042f2974d134710d9c Mon Sep 17 00:00:00 2001 From: Lee Shawn C Date: Wed, 8 Sep 2021 19:56:03 +0800 Subject: [PATCH] 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 Cc: Jani Nikula Cc: Vandita Kulkarni Cc: Cooper Chiou Cc: William Tseng Signed-off-by: Lee Shawn C Reviewed-by: Vandita Kulkarni Signed-off-by: Vandita Kulkarni Link: https://patchwork.freedesktop.org/patch/msgid/20210908115607.9633-2-shawn.c.lee@intel.com --- drivers/gpu/drm/i915/display/icl_dsi.c | 40 ++++++++++++++++------------------ 1 file changed, 19 insertions(+), 21 deletions(-) diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c index a1e35180d5dd..44289003b709 100644 --- a/drivers/gpu/drm/i915/display/icl_dsi.c +++ b/drivers/gpu/drm/i915/display/icl_dsi.c @@ -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; + } + + return true; } -static void wait_for_payload_credits(struct drm_i915_private *dev_priv, - enum transcoder dsi_trans) +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)); -- 2.11.0