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.syrj...@linux.intel.com>
Cc: Jani Nikula <jani.nik...@linux.intel.com>
Cc: Vandita Kulkarni <vandita.kulka...@intel.com>
Cc: Cooper Chiou <cooper.ch...@intel.com>
Cc: William Tseng <william.ts...@intel.com>
Signed-off-by: Lee Shawn C <shawn.c....@intel.com>
Reviewed-by: Vandita Kulkarni <vandita.kulka...@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));
--
2.17.1
