diff options
| author | Niko Tsirakis <[email protected]> | 2023-10-02 20:47:09 +0000 |
|---|---|---|
| committer | Jani Nikula <[email protected]> | 2023-10-04 18:34:20 +0300 |
| commit | cf37c0979e558213e2a2f87c2c3dfe644a66b210 (patch) | |
| tree | 54eecdbf2c88fd211cf515a8031ce045981e82cd | |
| parent | 14aebb78b994fd307ec26f82f9f8ccea2a12c6a1 (diff) | |
drm/i915/display/lspcon: Increase LSPCON mode settle timeout
This is to eliminate all cases of "*ERROR* LSPCON mode hasn't settled",
followed by link training errors. Intel engineers recommended increasing
this timeout and that does resolve the issue.
On some CometLake-based device designs the Parade PS175 takes more than
400ms to settle in PCON mode. 100 reboot trials on one device resulted
in a median settle time of 440ms and a maximum of 444ms. Even after
increasing the timeout to 500ms, 2% of devices still had this error. So
this increases the timeout to 800ms.
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/9443
Signed-off-by: Pablo Ceballos <[email protected]>
Signed-off-by: Niko Tsirakis <[email protected]>
Reviewed-by: Jani Nikula <[email protected]>
Signed-off-by: Jani Nikula <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_lspcon.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_lspcon.c b/drivers/gpu/drm/i915/display/intel_lspcon.c index 152a22a8ffd2..1d048fa98561 100644 --- a/drivers/gpu/drm/i915/display/intel_lspcon.c +++ b/drivers/gpu/drm/i915/display/intel_lspcon.c @@ -153,6 +153,18 @@ static enum drm_lspcon_mode lspcon_get_current_mode(struct intel_lspcon *lspcon) return current_mode; } +static int lspcon_get_mode_settle_timeout(struct intel_lspcon *lspcon) +{ + /* + * On some CometLake-based device designs the Parade PS175 takes more + * than 400ms to settle in PCON mode. 100 reboot trials on one device + * resulted in a median settle time of 440ms and a maximum of 444ms. + * Even after increasing the timeout to 500ms, 2% of devices still had + * this error. So this sets the timeout to 800ms. + */ + return lspcon->vendor == LSPCON_VENDOR_PARADE ? 800 : 400; +} + static enum drm_lspcon_mode lspcon_wait_mode(struct intel_lspcon *lspcon, enum drm_lspcon_mode mode) { @@ -167,7 +179,8 @@ static enum drm_lspcon_mode lspcon_wait_mode(struct intel_lspcon *lspcon, drm_dbg_kms(&i915->drm, "Waiting for LSPCON mode %s to settle\n", lspcon_mode_name(mode)); - wait_for((current_mode = lspcon_get_current_mode(lspcon)) == mode, 400); + wait_for((current_mode = lspcon_get_current_mode(lspcon)) == mode, + lspcon_get_mode_settle_timeout(lspcon)); if (current_mode != mode) drm_err(&i915->drm, "LSPCON mode hasn't settled\n"); |