From: Fangzhi Zuo Jerry.Zuo@amd.com
[ Upstream commit acea108fa067d140bd155161a79b1fcd967f4137 ]
[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 Jerry.Zuo@amd.com Acked-by: Solomon Chiu solomon.chiu@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- .../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 b55a433e829e..bfbd701a4c9a 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 <linux/pci.h> #include <linux/firmware.h> #include <linux/component.h> +#include <linux/dmi.h>
#include <drm/drm_atomic.h> #include <drm/drm_atomic_uapi.h> @@ -1391,6 +1392,41 @@ 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; @@ -1521,6 +1557,9 @@ static int amdgpu_dm_init(struct amdgpu_device *adev) }
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 7e44b0429448..4844601a5f47 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h @@ -546,6 +546,14 @@ 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 31ac1fce36f8..d864cae1af67 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 @@ -58,6 +58,8 @@ 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; @@ -76,6 +78,21 @@ 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;