Commit ad9dc91b authored by Rodrigo Vivi's avatar Rodrigo Vivi Committed by Daniel Vetter

drm/i915: Fix Sink CRC

In some cases like when PSR just got enabled the panel need more vblank
times to calculate CRC. I figured that out with the new PSR test cases
facing some cases that I had a green screen but a blank CRC. Even with
2 vblank waits on kernel + 2 vblank waits on test case.

So let's give up to 6 vblank wait time. However we now check for
TEST_CRC_COUNT that shows when panel finished to calculate CRC and
has it ready.

v2: Jani pointed out attempts decrements was wrong and should never reach
the error condition. And Daniel pointed out that EIO is more appropriated than
EGAIN. Also I realized that I have to read test_crc_count after setting
test_sink

v3: Rebase and adding error message

Cc: Todd Previte <tprevite@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarRodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: default avatarTodd Previte <tprevite@gmail.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
parent 6805b2a7
......@@ -3807,21 +3807,32 @@ int intel_dp_sink_crc(struct intel_dp *intel_dp, u8 *crc)
struct drm_device *dev = intel_dig_port->base.base.dev;
struct intel_crtc *intel_crtc =
to_intel_crtc(intel_dig_port->base.base.crtc);
u8 buf[1];
u8 buf;
int test_crc_count;
int attempts = 6;
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, buf) < 0)
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0)
return -EIO;
if (!(buf[0] & DP_TEST_CRC_SUPPORTED))
if (!(buf & DP_TEST_CRC_SUPPORTED))
return -ENOTTY;
if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
DP_TEST_SINK_START) < 0)
return -EIO;
/* Wait 2 vblanks to be sure we will have the correct CRC value */
intel_wait_for_vblank(dev, intel_crtc->pipe);
intel_wait_for_vblank(dev, intel_crtc->pipe);
drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf);
test_crc_count = buf & DP_TEST_COUNT_MASK;
do {
drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf);
intel_wait_for_vblank(dev, intel_crtc->pipe);
} while (--attempts && (buf & DP_TEST_COUNT_MASK) == test_crc_count);
if (attempts == 0) {
DRM_ERROR("Panel is unable to calculate CRC after 6 vblanks\n");
return -EIO;
}
if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0)
return -EIO;
......
......@@ -303,7 +303,8 @@
#define DP_TEST_CRC_B_CB 0x244
#define DP_TEST_SINK_MISC 0x246
#define DP_TEST_CRC_SUPPORTED (1 << 5)
# define DP_TEST_CRC_SUPPORTED (1 << 5)
# define DP_TEST_COUNT_MASK 0x7
#define DP_TEST_RESPONSE 0x260
# define DP_TEST_ACK (1 << 0)
......@@ -313,7 +314,7 @@
#define DP_TEST_EDID_CHECKSUM 0x261
#define DP_TEST_SINK 0x270
#define DP_TEST_SINK_START (1 << 0)
# define DP_TEST_SINK_START (1 << 0)
#define DP_PAYLOAD_TABLE_UPDATE_STATUS 0x2c0 /* 1.2 MST */
# define DP_PAYLOAD_TABLE_UPDATED (1 << 0)
......
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