[PATCH 07/10] drm/amdgpu: add concurrent baco reset support for XGMI

[Le Ma]

Currently each XGMI node reset wq does not run in parrallel because same work
item bound to same cpu runs in sequence. So change to bound the xgmi_reset_work
item to different cpus.

XGMI requires all nodes enter into baco within very close proximity before
any node exit baco. So schedule the xgmi_reset_work wq twice for enter/exit
baco respectively.

The default reset code path and methods do not change for vega20 production:
  - baco reset without xgmi/ras
  - psp reset with xgmi/ras

To enable baco for XGMI/RAS case, both 2 conditions below are needed:
  - amdgpu_ras_enable=2
  - baco-supported smu firmware

The case that PSP reset and baco reset coexist within an XGMI hive is not in
the consideration.

Change-Id: I9c08cf90134f940b42e20d2129ff87fba761c532
Signed-off-by: Le Ma <le.ma at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h        |  2 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 78 ++++++++++++++++++++++++++----
 2 files changed, 70 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index d120fe5..08929e6 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -998,6 +998,8 @@ struct amdgpu_device {
 	int				pstate;
 	/* enable runtime pm on the device */
 	bool                            runpm;
+
+	bool				in_baco;
 };
 
 static inline struct amdgpu_device *amdgpu_ttm_adev(struct ttm_bo_device *bdev)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index bd387bb..71abfe9 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -2654,7 +2654,13 @@ static void amdgpu_device_xgmi_reset_func(struct work_struct *__work)
 	struct amdgpu_device *adev =
 		container_of(__work, struct amdgpu_device, xgmi_reset_work);
 
-	adev->asic_reset_res =  amdgpu_asic_reset(adev);
+	if (amdgpu_asic_reset_method(adev) == AMD_RESET_METHOD_BACO)
+		adev->asic_reset_res = (adev->in_baco == false) ?
+				amdgpu_device_baco_enter(adev->ddev) :
+				amdgpu_device_baco_exit(adev->ddev);
+	else
+		adev->asic_reset_res = amdgpu_asic_reset(adev);
+
 	if (adev->asic_reset_res)
 		DRM_WARN("ASIC reset failed with error, %d for drm dev, %s",
 			 adev->asic_reset_res, adev->ddev->unique);
@@ -3796,6 +3802,7 @@ static int amdgpu_do_asic_reset(struct amdgpu_hive_info *hive,
 	struct amdgpu_device *tmp_adev = NULL;
 	bool need_full_reset = *need_full_reset_arg, vram_lost = false;
 	int r = 0;
+	int cpu = smp_processor_id();
 
 	/*
 	 * ASIC reset has to be done on all HGMI hive nodes ASAP
@@ -3803,21 +3810,24 @@ static int amdgpu_do_asic_reset(struct amdgpu_hive_info *hive,
 	 */
 	if (need_full_reset) {
 		list_for_each_entry(tmp_adev, device_list_handle, gmc.xgmi.head) {
-			/* For XGMI run all resets in parallel to speed up the process */
+			/*
+			 * For XGMI run all resets in parallel to speed up the
+			 * process by scheduling the highpri wq on different
+			 * cpus. For XGMI with baco reset, all nodes must enter
+			 * baco within close proximity before anyone exit.
+			 */
 			if (tmp_adev->gmc.xgmi.num_physical_nodes > 1) {
-				if (!queue_work(system_highpri_wq, &tmp_adev->xgmi_reset_work))
+				if (!queue_work_on(cpu, system_highpri_wq,
+						   &tmp_adev->xgmi_reset_work))
 					r = -EALREADY;
+				cpu = cpumask_next(cpu, cpu_online_mask);
 			} else
 				r = amdgpu_asic_reset(tmp_adev);
-
-			if (r) {
-				DRM_ERROR("ASIC reset failed with error, %d for drm dev, %s",
-					 r, tmp_adev->ddev->unique);
+			if (r)
 				break;
-			}
 		}
 
-		/* For XGMI wait for all PSP resets to complete before proceed */
+		/* For XGMI wait for all work to complete before proceed */
 		if (!r) {
 			list_for_each_entry(tmp_adev, device_list_handle,
 					    gmc.xgmi.head) {
@@ -3826,11 +3836,59 @@ static int amdgpu_do_asic_reset(struct amdgpu_hive_info *hive,
 					r = tmp_adev->asic_reset_res;
 					if (r)
 						break;
+					if(AMD_RESET_METHOD_BACO ==
+					   amdgpu_asic_reset_method(tmp_adev))
+						tmp_adev->in_baco = true;
 				}
 			}
 		}
-	}
 
+		/*
+		 * For XGMI with baco reset, need exit baco phase by scheduling
+		 * xgmi_reset_work one more time. PSP reset skips this phase.
+		 * Not assume the situation that PSP reset and baco reset
+		 * coexist within an XGMI hive.
+		 */
+
+		if (!r) {
+			cpu = smp_processor_id();
+			list_for_each_entry(tmp_adev, device_list_handle,
+					    gmc.xgmi.head) {
+				if (tmp_adev->gmc.xgmi.num_physical_nodes > 1
+				    && AMD_RESET_METHOD_BACO ==
+				    amdgpu_asic_reset_method(tmp_adev)) {
+					if (!queue_work_on(cpu,
+						system_highpri_wq,
+						&tmp_adev->xgmi_reset_work))
+						r = -EALREADY;
+					if (r)
+						break;
+					cpu = cpumask_next(cpu, cpu_online_mask);
+				}
+			}
+		}
+
+		if (!r) {
+			list_for_each_entry(tmp_adev, device_list_handle,
+					    gmc.xgmi.head) {
+				if (tmp_adev->gmc.xgmi.num_physical_nodes > 1
+				    && AMD_RESET_METHOD_BACO ==
+				    amdgpu_asic_reset_method(tmp_adev)) {
+					flush_work(&tmp_adev->xgmi_reset_work);
+					r = tmp_adev->asic_reset_res;
+					if (r)
+						break;
+					tmp_adev->in_baco = false;
+				}
+			}
+		}
+
+		if (r) {
+			DRM_ERROR("ASIC reset failed with error, %d for drm dev, %s",
+				 r, tmp_adev->ddev->unique);
+			goto end;
+		}
+	}
 
 	list_for_each_entry(tmp_adev, device_list_handle, gmc.xgmi.head) {
 		if (need_full_reset) {
-- 
2.7.4