From: Roman Li Date: Tue, 25 Jun 2024 17:23:36 +0000 (-0400) Subject: drm/amd/display: Replace assert with error message in dp_retrieve_lttpr_cap() X-Git-Tag: v6.12-rc1~126^2~17^2~433 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e8d77cfdd2698039667432b8569bac34d13508c1;p=thirdparty%2Fkernel%2Flinux.git drm/amd/display: Replace assert with error message in dp_retrieve_lttpr_cap() [Why] When assert in dp_retrieve_lttpr_cap() is hit, dmesg has traces like: RIP: 0010:dp_retrieve_lttpr_cap+0xcc/0x1a0 [amdgpu] Call Trace: dp_retrieve_lttpr_cap+0xcc/0x1a0 [amdgpu] report_bug+0x1e8/0x240 handle_bug+0x46/0x80 link_detect+0x35/0x580 [amdgpu] It happens when LTTPRs fail to increment dpcd repeater count. We have a recovery action in place for such cases. Assert is misleading, an indicative error in dmesg is more useful. [How] Remove ASSERT and use DC_LOG_ERROR instead. Reviewed-by: Michael Strauss Signed-off-by: Jerry Zuo Signed-off-by: Roman Li Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c index 46bb7a855bc21..c257e733044a6 100644 --- a/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c +++ b/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.c @@ -1541,7 +1541,11 @@ enum dc_status dp_retrieve_lttpr_cap(struct dc_link *link) * Override count to 1 if we receive a known bad count (0 or an invalid value) */ if ((link->chip_caps & EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) && (dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt) == 0)) { - ASSERT(0); + /* If you see this message consistently, either the host platform has FIXED_VS flag + * incorrectly configured or the sink device is returning an invalid count. + */ + DC_LOG_ERROR("lttpr_caps phy_repeater_cnt is 0x%x, forcing it to 0x80.", + link->dpcd_caps.lttpr_caps.phy_repeater_cnt); link->dpcd_caps.lttpr_caps.phy_repeater_cnt = 0x80; DC_LOG_DC("lttpr_caps forced phy_repeater_cnt = %d\n", link->dpcd_caps.lttpr_caps.phy_repeater_cnt); }