[v4 2/7] drm/amd/amdgpu: Implement SDMA soft reset directly for sdma v5

Jesse.zhang@amd.com jesse.zhang at amd.com
Tue Apr 8 08:36:28 UTC 2025


From: "Jesse.zhang at amd.com" <Jesse.zhang at amd.com>

This patch introduces a new function `amdgpu_sdma_soft_reset` to handle SDMA soft resets directly,
rather than relying on the DPM interface.

1. **New `amdgpu_sdma_soft_reset` Function**:
   - Implements a soft reset for SDMA engines by directly writing to the hardware registers.
   - Handles SDMA versions 4.x and 5.x separately:
     - For SDMA 4.x, the existing `amdgpu_dpm_reset_sdma` function is used for backward compatibility.
     - For SDMA 5.x, the driver directly manipulates the `GRBM_SOFT_RESET` register to reset the specified SDMA instance.

2. **Integration into `amdgpu_sdma_reset_engine`**:
   - The `amdgpu_sdma_soft_reset` function is called during the SDMA reset process, replacing the previous call to `amdgpu_dpm_reset_sdma`.

v2: move soft reset into a helper funciton (Alex)

Suggested-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Jesse Zhang <jesse.zhang at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c | 38 +++++++++++++++++++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h |  1 +
 drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c   | 29 +++++++++++++++
 drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c   | 45 +++++++++++++++---------
 4 files changed, 95 insertions(+), 18 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c
index 541b349e0310..96d0350c7754 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.c
@@ -26,6 +26,8 @@
 #include "amdgpu_sdma.h"
 #include "amdgpu_ras.h"
 #include "amdgpu_reset.h"
+#include "gc/gc_10_1_0_offset.h"
+#include "gc/gc_10_3_0_sh_mask.h"
 
 #define AMDGPU_CSA_SDMA_SIZE 64
 /* SDMA CSA reside in the 3rd page of CSA */
@@ -553,6 +555,40 @@ void amdgpu_sdma_register_on_reset_callbacks(struct amdgpu_device *adev, struct
 	list_add_tail(&funcs->list, &adev->sdma.reset_callback_list);
 }
 
+static int amdgpu_sdma_soft_reset(struct amdgpu_device *adev, u32 instance_id)
+{
+	struct amdgpu_sdma_instance *sdma_instance = &adev->sdma.instance[instance_id];
+	int r = 0;
+
+	switch (amdgpu_ip_version(adev, SDMA0_HWIP, 0)) {
+	case IP_VERSION(4, 4, 2):
+	case IP_VERSION(4, 4, 4):
+	case IP_VERSION(4, 4, 5):
+		/* For SDMA 4.x, use the existing DPM interface for backward compatibility */
+		r = amdgpu_dpm_reset_sdma(adev, 1 << instance_id);
+		break;
+	case IP_VERSION(5, 0, 0):
+	case IP_VERSION(5, 0, 1):
+	case IP_VERSION(5, 0, 2):
+	case IP_VERSION(5, 0, 5):
+	case IP_VERSION(5, 2, 0):
+	case IP_VERSION(5, 2, 2):
+	case IP_VERSION(5, 2, 4):
+	case IP_VERSION(5, 2, 5):
+	case IP_VERSION(5, 2, 6):
+	case IP_VERSION(5, 2, 3):
+	case IP_VERSION(5, 2, 1):
+	case IP_VERSION(5, 2, 7):
+		if (sdma_instance->funcs->soft_reset_kernel_queue)
+			r = sdma_instance->funcs->soft_reset_kernel_queue(adev, instance_id);
+		break;
+	default:
+		break;
+	}
+
+	return r;
+}
+
 /**
  * amdgpu_sdma_reset_engine - Reset a specific SDMA engine
  * @adev: Pointer to the AMDGPU device
@@ -587,7 +623,7 @@ int amdgpu_sdma_reset_engine(struct amdgpu_device *adev, uint32_t instance_id)
 		sdma_instance->funcs->stop_kernel_queue(sdma_gfx_ring);
 
 	/* Perform the SDMA reset for the specified instance */
-	ret = amdgpu_dpm_reset_sdma(adev, 1 << instance_id);
+	ret = amdgpu_sdma_soft_reset(adev, instance_id);
 	if (ret) {
 		dev_err(adev->dev, "Failed to reset SDMA instance %u\n", instance_id);
 		goto exit;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h
index 620fd7663526..bf83d6646238 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_sdma.h
@@ -53,6 +53,7 @@ enum amdgpu_sdma_irq {
 struct amdgpu_sdma_funcs {
 	int (*stop_kernel_queue)(struct amdgpu_ring *ring);
 	int (*start_kernel_queue)(struct amdgpu_ring *ring);
+	int (*soft_reset_kernel_queue)(struct amdgpu_device *adev, u32 instance_id);
 };
 
 struct amdgpu_sdma_instance {
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c
index e1348b6d9c6a..d516add85dd4 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v5_0.c
@@ -1323,6 +1323,34 @@ static void sdma_v5_0_ring_emit_reg_write_reg_wait(struct amdgpu_ring *ring,
 	amdgpu_ring_emit_reg_wait(ring, reg1, mask, mask);
 }
 
+static int sdma_v5_0_soft_reset_engine(struct amdgpu_device *adev, u32 instance_id)
+{
+	u32 grbm_soft_reset;
+	u32 tmp;
+
+	grbm_soft_reset = REG_SET_FIELD(0,
+					GRBM_SOFT_RESET, SOFT_RESET_SDMA0,
+					1);
+	grbm_soft_reset <<= instance_id;
+
+	tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+	tmp |= grbm_soft_reset;
+	DRM_DEBUG("GRBM_SOFT_RESET=0x%08X\n", tmp);
+	WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, tmp);
+	tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+
+	udelay(50);
+
+	tmp &= ~grbm_soft_reset;
+	WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, tmp);
+	tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+	return 0;
+}
+
+static const struct amdgpu_sdma_funcs sdma_v5_0_sdma_funcs = {
+	.soft_reset_kernel_queue = &sdma_v5_0_soft_reset_engine,
+};
+
 static int sdma_v5_0_early_init(struct amdgpu_ip_block *ip_block)
 {
 	struct amdgpu_device *adev = ip_block->adev;
@@ -1365,6 +1393,7 @@ static int sdma_v5_0_sw_init(struct amdgpu_ip_block *ip_block)
 		return r;
 
 	for (i = 0; i < adev->sdma.num_instances; i++) {
+		adev->sdma.instance[i].funcs = &sdma_v5_0_sdma_funcs;
 		ring = &adev->sdma.instance[i].ring;
 		ring->ring_obj = NULL;
 		ring->use_doorbell = true;
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c b/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
index 964f12afac9e..6f9a5ff7880e 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v5_2.c
@@ -759,37 +759,47 @@ static int sdma_v5_2_load_microcode(struct amdgpu_device *adev)
 	return 0;
 }
 
-static int sdma_v5_2_soft_reset(struct amdgpu_ip_block *ip_block)
+static int sdma_v5_2_soft_reset_engine(struct amdgpu_device *adev, u32 instance_id)
 {
-	struct amdgpu_device *adev = ip_block->adev;
 	u32 grbm_soft_reset;
 	u32 tmp;
-	int i;
 
-	for (i = 0; i < adev->sdma.num_instances; i++) {
-		grbm_soft_reset = REG_SET_FIELD(0,
-						GRBM_SOFT_RESET, SOFT_RESET_SDMA0,
-						1);
-		grbm_soft_reset <<= i;
+	grbm_soft_reset = REG_SET_FIELD(0,
+					GRBM_SOFT_RESET, SOFT_RESET_SDMA0,
+					1);
+	grbm_soft_reset <<= instance_id;
 
-		tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
-		tmp |= grbm_soft_reset;
-		DRM_DEBUG("GRBM_SOFT_RESET=0x%08X\n", tmp);
-		WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, tmp);
-		tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+	tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+	tmp |= grbm_soft_reset;
+	DRM_DEBUG("GRBM_SOFT_RESET=0x%08X\n", tmp);
+	WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, tmp);
+	tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
 
-		udelay(50);
+	udelay(50);
+
+	tmp &= ~grbm_soft_reset;
+	WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, tmp);
+	tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+	return 0;
+}
 
-		tmp &= ~grbm_soft_reset;
-		WREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET, tmp);
-		tmp = RREG32_SOC15(GC, 0, mmGRBM_SOFT_RESET);
+static int sdma_v5_2_soft_reset(struct amdgpu_ip_block *ip_block)
+{
+	struct amdgpu_device *adev = ip_block->adev;
+	int i;
 
+	for (i = 0; i < adev->sdma.num_instances; i++) {
+		sdma_v5_2_soft_reset_engine(adev, i);
 		udelay(50);
 	}
 
 	return 0;
 }
 
+static const struct amdgpu_sdma_funcs sdma_v5_2_sdma_funcs = {
+	.soft_reset_kernel_queue = &sdma_v5_2_soft_reset_engine,
+};
+
 /**
  * sdma_v5_2_start - setup and start the async dma engines
  *
@@ -1302,6 +1312,7 @@ static int sdma_v5_2_sw_init(struct amdgpu_ip_block *ip_block)
 	}
 
 	for (i = 0; i < adev->sdma.num_instances; i++) {
+		adev->sdma.instance[i].funcs = &sdma_v5_2_sdma_funcs;
 		ring = &adev->sdma.instance[i].ring;
 		ring->ring_obj = NULL;
 		ring->use_doorbell = true;
-- 
2.25.1



More information about the amd-gfx mailing list