[PATCH] drm/amdkfd: Retrieve SDMA numbers from amdgpu

Amber Lin Amber.Lin at amd.com
Wed Nov 17 20:36:48 UTC 2021


Instead of hard coding the number of sdma engines and the number of
sdma_xgmi engines in the device_info table, get the number of toal SDMA
instances from amdgpu. The first two engines are sdma engines and the
rest are sdma-xgmi engines unless the ASIC doesn't support XGMI.

v2: Move get_num_*_sdma_engines to global and shared by queues manager
    and topology.
v3: Use gmc.xgmi.supported to justify the SDMA PCIe/XGMI assignment

Signed-off-by: Amber Lin <Amber.Lin at amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling at amd.com>
---
 drivers/gpu/drm/amd/amdkfd/kfd_device.c       | 20 ++++++++++++
 .../drm/amd/amdkfd/kfd_device_queue_manager.c | 31 +++++++------------
 drivers/gpu/drm/amd/amdkfd/kfd_priv.h         |  3 ++
 drivers/gpu/drm/amd/amdkfd/kfd_topology.c     |  5 ++-
 4 files changed, 36 insertions(+), 23 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device.c b/drivers/gpu/drm/amd/amdkfd/kfd_device.c
index ce9f4e562bac..ec1f6bacb61e 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device.c
@@ -1516,6 +1516,26 @@ void kgd2kfd_smi_event_throttle(struct kfd_dev *kfd, uint64_t throttle_bitmask)
 		kfd_smi_event_update_thermal_throttling(kfd, throttle_bitmask);
 }
 
+/* get_num_sdma_engines returns the number of PCIe optimized SDMA and
+ * get_num_xgmi_sdma_engines returns the number of XGMI SDMA.
+ * When the device has more than two engines, we reserve two for PCIe to enable
+ * full-duplex and the rest are used as XGMI.
+ */
+unsigned int get_num_sdma_engines(struct kfd_dev *kdev)
+{
+	/* If XGMI is not supported, all SDMA engines are PCIe */
+	if (!kdev->adev->gmc.xgmi.supported)
+		return kdev->adev->sdma.num_instances;
+
+	return min(kdev->adev->sdma.num_instances, 2);
+}
+
+unsigned int get_num_xgmi_sdma_engines(struct kfd_dev *kdev)
+{
+	/* After reserved for PCIe, the rest of engines are XGMI */
+	return kdev->adev->sdma.num_instances - get_num_sdma_engines(kdev);
+}
+
 #if defined(CONFIG_DEBUG_FS)
 
 /* This function will send a package to HIQ to hang the HWS
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
index 62fe28244a80..5f2886cf4d7e 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
@@ -99,31 +99,22 @@ unsigned int get_pipes_per_mec(struct device_queue_manager *dqm)
 	return dqm->dev->shared_resources.num_pipe_per_mec;
 }
 
-static unsigned int get_num_sdma_engines(struct device_queue_manager *dqm)
-{
-	return dqm->dev->device_info->num_sdma_engines;
-}
-
-static unsigned int get_num_xgmi_sdma_engines(struct device_queue_manager *dqm)
-{
-	return dqm->dev->device_info->num_xgmi_sdma_engines;
-}
-
 static unsigned int get_num_all_sdma_engines(struct device_queue_manager *dqm)
 {
-	return get_num_sdma_engines(dqm) + get_num_xgmi_sdma_engines(dqm);
+	return get_num_sdma_engines(dqm->dev) +
+		get_num_xgmi_sdma_engines(dqm->dev);
 }
 
 unsigned int get_num_sdma_queues(struct device_queue_manager *dqm)
 {
-	return dqm->dev->device_info->num_sdma_engines
-			* dqm->dev->device_info->num_sdma_queues_per_engine;
+	return get_num_sdma_engines(dqm->dev) *
+		dqm->dev->device_info->num_sdma_queues_per_engine;
 }
 
 unsigned int get_num_xgmi_sdma_queues(struct device_queue_manager *dqm)
 {
-	return dqm->dev->device_info->num_xgmi_sdma_engines
-			* dqm->dev->device_info->num_sdma_queues_per_engine;
+	return get_num_xgmi_sdma_engines(dqm->dev) *
+		dqm->dev->device_info->num_sdma_queues_per_engine;
 }
 
 void program_sh_mem_settings(struct device_queue_manager *dqm,
@@ -1054,9 +1045,9 @@ static int allocate_sdma_queue(struct device_queue_manager *dqm,
 		dqm->sdma_bitmap &= ~(1ULL << bit);
 		q->sdma_id = bit;
 		q->properties.sdma_engine_id = q->sdma_id %
-				get_num_sdma_engines(dqm);
+				get_num_sdma_engines(dqm->dev);
 		q->properties.sdma_queue_id = q->sdma_id /
-				get_num_sdma_engines(dqm);
+				get_num_sdma_engines(dqm->dev);
 	} else if (q->properties.type == KFD_QUEUE_TYPE_SDMA_XGMI) {
 		if (dqm->xgmi_sdma_bitmap == 0) {
 			pr_err("No more XGMI SDMA queue to allocate\n");
@@ -1071,10 +1062,10 @@ static int allocate_sdma_queue(struct device_queue_manager *dqm,
 		 * assumes the first N engines are always
 		 * PCIe-optimized ones
 		 */
-		q->properties.sdma_engine_id = get_num_sdma_engines(dqm) +
-				q->sdma_id % get_num_xgmi_sdma_engines(dqm);
+		q->properties.sdma_engine_id = get_num_sdma_engines(dqm->dev) +
+			q->sdma_id % get_num_xgmi_sdma_engines(dqm->dev);
 		q->properties.sdma_queue_id = q->sdma_id /
-				get_num_xgmi_sdma_engines(dqm);
+			get_num_xgmi_sdma_engines(dqm->dev);
 	}
 
 	pr_debug("SDMA engine id: %d\n", q->properties.sdma_engine_id);
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
index 1d3f012bcd2a..85efa100a80d 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_priv.h
@@ -213,6 +213,9 @@ struct kfd_device_info {
 	unsigned int num_sdma_queues_per_engine;
 };
 
+unsigned int get_num_sdma_engines(struct kfd_dev *kdev);
+unsigned int get_num_xgmi_sdma_engines(struct kfd_dev *kdev);
+
 struct kfd_mem_obj {
 	uint32_t range_start;
 	uint32_t range_end;
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_topology.c b/drivers/gpu/drm/amd/amdkfd/kfd_topology.c
index a3f590e17973..fff4cc99fb5d 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_topology.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_topology.c
@@ -1392,9 +1392,8 @@ int kfd_topology_add_device(struct kfd_dev *gpu)
 		gpu->shared_resources.drm_render_minor;
 
 	dev->node_props.hive_id = gpu->hive_id;
-	dev->node_props.num_sdma_engines = gpu->device_info->num_sdma_engines;
-	dev->node_props.num_sdma_xgmi_engines =
-				gpu->device_info->num_xgmi_sdma_engines;
+	dev->node_props.num_sdma_engines = get_num_sdma_engines(gpu);
+	dev->node_props.num_sdma_xgmi_engines = get_num_xgmi_sdma_engines(gpu);
 	dev->node_props.num_sdma_queues_per_engine =
 				gpu->device_info->num_sdma_queues_per_engine;
 	dev->node_props.num_gws = (dev->gpu->gws &&
-- 
2.17.1



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