From: Wayne Lin wayne.lin@amd.com

[Why] Specific TBT4 dock doesn't send out short HPD to notify source that IRQ event DOWN_REP_MSG_RDY is set. Which violates the spec and cause source can't send out streams to mst sinks.

[How] To cover this misbehavior, add an additional polling method to detect DOWN_REP_MSG_RDY is set. HPD driven handling method is still kept. Just hook up our handler to drm mgr->cbs->poll_hpd_irq().

Cc: Mario Limonciello mario.limonciello@amd.com Cc: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Reviewed-by: Jerry Zuo jerry.zuo@amd.com Acked-by: Alan Liu haoping.liu@amd.com Signed-off-by: Wayne Lin wayne.lin@amd.com --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 117 +++++------------- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 7 ++ .../display/amdgpu_dm/amdgpu_dm_mst_types.c | 110 ++++++++++++++++ .../display/amdgpu_dm/amdgpu_dm_mst_types.h | 11 ++ 4 files changed, 159 insertions(+), 86 deletions(-)

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 28f8ac6007fb..42fa632523a2 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -1347,6 +1347,15 @@ static void dm_handle_hpd_rx_offload_work(struct work_struct *work) if (amdgpu_in_reset(adev)) goto skip;

+ if (offload_work->data.bytes.device_service_irq.bits.UP_REQ_MSG_RDY || + offload_work->data.bytes.device_service_irq.bits.DOWN_REP_MSG_RDY) { + dm_handle_mst_sideband_msg_ready_event(&aconnector->mst_mgr, DOWN_OR_UP_MSG_RDY_EVENT); + spin_lock_irqsave(&offload_work->offload_wq->offload_lock, flags); + offload_work->offload_wq->is_handling_mst_msg_rdy_event = false; + spin_unlock_irqrestore(&offload_work->offload_wq->offload_lock, flags); + goto skip; + } + mutex_lock(&adev->dm.dc_lock); if (offload_work->data.bytes.device_service_irq.bits.AUTOMATED_TEST) { dc_link_dp_handle_automated_test(dc_link); @@ -3232,87 +3241,6 @@ static void handle_hpd_irq(void *param)

}

-static void dm_handle_mst_sideband_msg(struct amdgpu_dm_connector *aconnector) -{ - u8 esi[DP_PSR_ERROR_STATUS - DP_SINK_COUNT_ESI] = { 0 }; - u8 dret; - bool new_irq_handled = false; - int dpcd_addr; - int dpcd_bytes_to_read; - - const int max_process_count = 30; - int process_count = 0; - - const struct dc_link_status *link_status = dc_link_get_status(aconnector->dc_link); - - if (link_status->dpcd_caps->dpcd_rev.raw < 0x12) { - dpcd_bytes_to_read = DP_LANE0_1_STATUS - DP_SINK_COUNT; - /* DPCD 0x200 - 0x201 for downstream IRQ */ - dpcd_addr = DP_SINK_COUNT; - } else { - dpcd_bytes_to_read = DP_PSR_ERROR_STATUS - DP_SINK_COUNT_ESI; - /* DPCD 0x2002 - 0x2005 for downstream IRQ */ - dpcd_addr = DP_SINK_COUNT_ESI; - } - - dret = drm_dp_dpcd_read( - &aconnector->dm_dp_aux.aux, - dpcd_addr, - esi, - dpcd_bytes_to_read); - - while (dret == dpcd_bytes_to_read && - process_count < max_process_count) { - u8 ack[DP_PSR_ERROR_STATUS - DP_SINK_COUNT_ESI] = {}; - u8 retry; - - dret = 0; - - process_count++; - - DRM_DEBUG_DRIVER("ESI %02x %02x %02x\n", esi[0], esi[1], esi[2]); - /* handle HPD short pulse irq */ - if (aconnector->mst_mgr.mst_state) - drm_dp_mst_hpd_irq_handle_event(&aconnector->mst_mgr, - esi, - ack, - &new_irq_handled); - - if (new_irq_handled) { - /* ACK at DPCD to notify down stream */ - for (retry = 0; retry < 3; retry++) { - ssize_t wret; - - wret = drm_dp_dpcd_writeb(&aconnector->dm_dp_aux.aux, - dpcd_addr + 1, - ack[1]); - if (wret == 1) - break; - } - - if (retry == 3) { - DRM_ERROR("Failed to ack MST event.\n"); - return; - } - - drm_dp_mst_hpd_irq_send_new_request(&aconnector->mst_mgr); - /* check if there is new irq to be handled */ - dret = drm_dp_dpcd_read( - &aconnector->dm_dp_aux.aux, - dpcd_addr, - esi, - dpcd_bytes_to_read); - - new_irq_handled = false; - } else { - break; - } - } - - if (process_count == max_process_count) - DRM_DEBUG_DRIVER("Loop exceeded max iterations\n"); -} - static void schedule_hpd_rx_offload_work(struct hpd_rx_irq_offload_work_queue *offload_wq, union hpd_irq_data hpd_irq_data) { @@ -3374,7 +3302,23 @@ static void handle_hpd_rx_irq(void *param) if (dc_link_dp_allow_hpd_rx_irq(dc_link)) { if (hpd_irq_data.bytes.device_service_irq.bits.UP_REQ_MSG_RDY || hpd_irq_data.bytes.device_service_irq.bits.DOWN_REP_MSG_RDY) { - dm_handle_mst_sideband_msg(aconnector); + bool skip = false; + + /* + * DOWN_REP_MSG_RDY is also handled by polling method + * mgr->cbs->poll_hpd_irq() + */ + spin_lock(&offload_wq->offload_lock); + skip = offload_wq->is_handling_mst_msg_rdy_event; + + if (!skip) + offload_wq->is_handling_mst_msg_rdy_event = true; + + spin_unlock(&offload_wq->offload_lock); + + if (!skip) + schedule_hpd_rx_offload_work(offload_wq, hpd_irq_data); + goto out; }

@@ -3483,11 +3427,11 @@ static void register_hpd_handlers(struct amdgpu_device *adev) amdgpu_dm_irq_register_interrupt(adev, &int_params, handle_hpd_rx_irq, (void *) aconnector); - - if (adev->dm.hpd_rx_offload_wq) - adev->dm.hpd_rx_offload_wq[dc_link->link_index].aconnector = - aconnector; } + + if (adev->dm.hpd_rx_offload_wq) + adev->dm.hpd_rx_offload_wq[connector->index].aconnector = + aconnector; } }

@@ -7300,6 +7244,7 @@ void amdgpu_dm_connector_init_helper(struct amdgpu_display_manager *dm, aconnector->as_type = ADAPTIVE_SYNC_TYPE_NONE; memset(&aconnector->vsdb_info, 0, sizeof(aconnector->vsdb_info)); mutex_init(&aconnector->hpd_lock); + mutex_init(&aconnector->handle_mst_msg_ready);

/* * configure support HPD hot plug connector_>polled default value is 0 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 4561f55afa99..9fb5bb3a75a7 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h @@ -194,6 +194,11 @@ struct hpd_rx_irq_offload_work_queue { * we're handling link loss */ bool is_handling_link_loss; + /** + * @is_handling_mst_msg_rdy_event: Used to prevent inserting mst message + * ready event when we're already handling mst message ready event + */ + bool is_handling_mst_msg_rdy_event; /** * @aconnector: The aconnector that this work queue is attached to */ @@ -638,6 +643,8 @@ struct amdgpu_dm_connector { struct drm_dp_mst_port *mst_output_port; struct amdgpu_dm_connector *mst_root; struct drm_dp_aux *dsc_aux; + struct mutex handle_mst_msg_ready; + /* TODO see if we can merge with ddc_bus or make a dm_connector */ struct amdgpu_i2c_adapter *i2c;

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 95eefa6b4f2f..1d343f16e5b8 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 @@ -620,8 +620,118 @@ dm_dp_add_mst_connector(struct drm_dp_mst_topology_mgr *mgr, return connector; }

+void dm_handle_mst_sideband_msg_ready_event( + struct drm_dp_mst_topology_mgr *mgr, + enum mst_msg_ready_type msg_rdy_type) +{ + uint8_t esi[DP_PSR_ERROR_STATUS - DP_SINK_COUNT_ESI] = { 0 }; + uint8_t dret; + bool new_irq_handled = false; + int dpcd_addr; + uint8_t dpcd_bytes_to_read; + const uint8_t max_process_count = 30; + uint8_t process_count = 0; + u8 retry; + struct amdgpu_dm_connector *aconnector = + container_of(mgr, struct amdgpu_dm_connector, mst_mgr); + + + const struct dc_link_status *link_status = dc_link_get_status(aconnector->dc_link); + + if (link_status->dpcd_caps->dpcd_rev.raw < 0x12) { + dpcd_bytes_to_read = DP_LANE0_1_STATUS - DP_SINK_COUNT; + /* DPCD 0x200 - 0x201 for downstream IRQ */ + dpcd_addr = DP_SINK_COUNT; + } else { + dpcd_bytes_to_read = DP_PSR_ERROR_STATUS - DP_SINK_COUNT_ESI; + /* DPCD 0x2002 - 0x2005 for downstream IRQ */ + dpcd_addr = DP_SINK_COUNT_ESI; + } + + mutex_lock(&aconnector->handle_mst_msg_ready); + + while (process_count < max_process_count) { + u8 ack[DP_PSR_ERROR_STATUS - DP_SINK_COUNT_ESI] = {}; + + process_count++; + + dret = drm_dp_dpcd_read( + &aconnector->dm_dp_aux.aux, + dpcd_addr, + esi, + dpcd_bytes_to_read); + + if (dret != dpcd_bytes_to_read) { + DRM_DEBUG_KMS("DPCD read and acked number is not as expected!"); + break; + } + + DRM_DEBUG_DRIVER("ESI %02x %02x %02x\n", esi[0], esi[1], esi[2]); + + switch (msg_rdy_type) { + case DOWN_REP_MSG_RDY_EVENT: + /* Only handle DOWN_REP_MSG_RDY case*/ + esi[1] &= DP_DOWN_REP_MSG_RDY; + break; + case UP_REQ_MSG_RDY_EVENT: + /* Only handle UP_REQ_MSG_RDY case*/ + esi[1] &= DP_UP_REQ_MSG_RDY; + break; + default: + /* Handle both cases*/ + esi[1] &= (DP_DOWN_REP_MSG_RDY | DP_UP_REQ_MSG_RDY); + break; + } + + if (!esi[1]) + break; + + /* handle MST irq */ + if (aconnector->mst_mgr.mst_state) + drm_dp_mst_hpd_irq_handle_event(&aconnector->mst_mgr, + esi, + ack, + &new_irq_handled); + + if (new_irq_handled) { + /* ACK at DPCD to notify down stream */ + for (retry = 0; retry < 3; retry++) { + ssize_t wret; + + wret = drm_dp_dpcd_writeb(&aconnector->dm_dp_aux.aux, + dpcd_addr + 1, + ack[1]); + if (wret == 1) + break; + } + + if (retry == 3) { + DRM_ERROR("Failed to ack MST event.\n"); + return; + } + + drm_dp_mst_hpd_irq_send_new_request(&aconnector->mst_mgr); + + new_irq_handled = false; + } else { + break; + } + } + + mutex_unlock(&aconnector->handle_mst_msg_ready); + + if (process_count == max_process_count) + DRM_DEBUG_DRIVER("Loop exceeded max iterations\n"); +} + +static void dm_handle_mst_down_rep_msg_ready(struct drm_dp_mst_topology_mgr *mgr) +{ + dm_handle_mst_sideband_msg_ready_event(mgr, DOWN_REP_MSG_RDY_EVENT); +} + static const struct drm_dp_mst_topology_cbs dm_mst_cbs = { .add_connector = dm_dp_add_mst_connector, + .poll_hpd_irq = dm_handle_mst_down_rep_msg_ready, };

void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h index 1e4ede1e57ab..37c820ab0fdb 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.h @@ -49,6 +49,13 @@ #define PBN_FEC_OVERHEAD_MULTIPLIER_8B_10B 1031 #define PBN_FEC_OVERHEAD_MULTIPLIER_128B_132B 1000

+enum mst_msg_ready_type { + NONE_MSG_RDY_EVENT = 0, + DOWN_REP_MSG_RDY_EVENT = 1, + UP_REQ_MSG_RDY_EVENT = 2, + DOWN_OR_UP_MSG_RDY_EVENT = 3 +}; + struct amdgpu_display_manager; struct amdgpu_dm_connector;

@@ -61,6 +68,10 @@ void amdgpu_dm_initialize_dp_connector(struct amdgpu_display_manager *dm, void dm_dp_create_fake_mst_encoders(struct amdgpu_device *adev);

+void dm_handle_mst_sideband_msg_ready_event( + struct drm_dp_mst_topology_mgr *mgr, + enum mst_msg_ready_type msg_rdy_type); + struct dsc_mst_fairness_vars { int pbn; bool dsc_enabled;