From 57b9f3384c64e37bbdad7f127625ac3733d11e5c Mon Sep 17 00:00:00 2001 From: Fangzhi Zuo Date: Wed, 6 Jul 2022 15:52:46 -0400 Subject: [PATCH] drm/amd/display: Ignore First MST Sideband Message Return Error [why] First MST sideband message returns AUX_RET_ERROR_HPD_DISCON on certain intel platform. Aux transaction considered failure if HPD unexpected pulled low. The actual aux transaction success in such case, hence do not return error. [how] Not returning error when AUX_RET_ERROR_HPD_DISCON detected on the first sideband message. v2: squash in additional DMI entries v3: squash in static fix Signed-off-by: Fangzhi Zuo Acked-by: Solomon Chiu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 39 +++++++++++++++++++ .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 8 ++++ .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 17 ++++++++ 3 files changed, 64 insertions(+) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index a715fc7d53e8..ea22bdae7a6e 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -72,6 +72,7 @@ #include #include #include +#include #include #include @@ -1401,6 +1402,41 @@ static bool dm_should_disable_stutter(struct pci_dev *pdev) return false; } +static const struct dmi_system_id hpd_disconnect_quirk_table[] = { + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Precision 3660"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Precision 3260"), + }, + }, + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Precision 3460"), + }, + }, + {} +}; + +static void retrieve_dmi_info(struct amdgpu_display_manager *dm) +{ + const struct dmi_system_id *dmi_id; + + dm->aux_hpd_discon_quirk = false; + + dmi_id = dmi_first_match(hpd_disconnect_quirk_table); + if (dmi_id) { + dm->aux_hpd_discon_quirk = true; + DRM_INFO("aux_hpd_discon_quirk attached\n"); + } +} + static int amdgpu_dm_init(struct amdgpu_device *adev) { struct dc_init_data init_data; @@ -1529,6 +1565,9 @@ static int amdgpu_dm_init(struct amdgpu_device *adev) init_data.flags.enable_mipi_converter_optimization = true; INIT_LIST_HEAD(&adev->dm.da_list); + + retrieve_dmi_info(&adev->dm); + /* Display Core create. */ adev->dm.dc = dc_create(&init_data); diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h index 73755b304299..7bd750e9f891 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h @@ -547,6 +547,14 @@ struct amdgpu_display_manager { * last successfully applied backlight values. */ u32 actual_brightness[AMDGPU_DM_MAX_NUM_EDP]; + + /** + * @aux_hpd_discon_quirk: + * + * quirk for hpd discon while aux is on-going. + * occurred on certain intel platform + */ + bool aux_hpd_discon_quirk; }; enum dsc_clock_force_state { diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index 03ca9083f5e9..1f722309cfdd 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -56,6 +56,8 @@ static ssize_t dm_dp_aux_transfer(struct drm_dp_aux *aux, ssize_t result = 0; struct aux_payload payload; enum aux_return_code_type operation_result; + struct amdgpu_device *adev; + struct ddc_service *ddc; if (WARN_ON(msg->size > 16)) return -E2BIG; @@ -74,6 +76,21 @@ static ssize_t dm_dp_aux_transfer(struct drm_dp_aux *aux, result = dc_link_aux_transfer_raw(TO_DM_AUX(aux)->ddc_service, &payload, &operation_result); + /* + * w/a on certain intel platform where hpd is unexpected to pull low during + * 1st sideband message transaction by return AUX_RET_ERROR_HPD_DISCON + * aux transaction is succuess in such case, therefore bypass the error + */ + ddc = TO_DM_AUX(aux)->ddc_service; + adev = ddc->ctx->driver_context; + if (adev->dm.aux_hpd_discon_quirk) { + if (msg->address == DP_SIDEBAND_MSG_DOWN_REQ_BASE && + operation_result == AUX_RET_ERROR_HPD_DISCON) { + result = 0; + operation_result = AUX_RET_SUCCESS; + } + } + if (payload.write && result >= 0) result = msg->size; -- 2.20.1