[PATCH v2 1/1] drm/msm: Expose uche trap base via uapi

Danylo Piliaiev danylo.piliaiev at gmail.com
Tue Dec 3 17:40:11 UTC 2024


On at least a6xx+, shader could read 64b ALWAYSON counter
from UCHE_TRAP_BASE+0 address. In Mesa it will be used
to implement VK_KHR_shader_clock and GL_ARB_shader_clock.
These extensions provide shader functions to query a real-time or
monotonically incrementing counter at the subgroup level or
across the device level.

On a4xx and a5xx it was not tested what is at UCHE_TRAP_BASE
address, there uche trap base is exposed just for completeness.

Signed-off-by: Danylo Piliaiev <dpiliaiev at igalia.com>
---
Changes in v2:
- Rebased on top of https://patchwork.freedesktop.org/series/141667/
  in order to return error via UERR when there is no uche trap base.
- Updated commit message to explain why we need to expose the value.

---
 drivers/gpu/drm/msm/adreno/a4xx_gpu.c   |  6 ++++--
 drivers/gpu/drm/msm/adreno/a5xx_gpu.c   | 10 ++++++----
 drivers/gpu/drm/msm/adreno/a6xx_gpu.c   | 12 +++++++-----
 drivers/gpu/drm/msm/adreno/adreno_gpu.c |  5 +++++
 drivers/gpu/drm/msm/adreno/adreno_gpu.h |  2 ++
 include/uapi/drm/msm_drm.h              |  1 +
 6 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a4xx_gpu.c b/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
index 50c490b492f0..f1b18a6663f7 100644
--- a/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a4xx_gpu.c
@@ -251,8 +251,8 @@ static int a4xx_hw_init(struct msm_gpu *gpu)
 		gpu_write(gpu, REG_A4XX_UCHE_CACHE_WAYS_VFD, 0x07);
 
 	/* Disable L2 bypass to avoid UCHE out of bounds errors */
-	gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_LO, 0xffff0000);
-	gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_HI, 0xffff0000);
+	gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_LO, lower_32_bits(adreno_gpu->uche_trap_base));
+	gpu_write(gpu, REG_A4XX_UCHE_TRAP_BASE_HI, upper_32_bits(adreno_gpu->uche_trap_base));
 
 	gpu_write(gpu, REG_A4XX_CP_DEBUG, (1 << 25) |
 			(adreno_is_a420(adreno_gpu) ? (1 << 29) : 0));
@@ -693,6 +693,8 @@ struct msm_gpu *a4xx_gpu_init(struct drm_device *dev)
 	if (ret)
 		goto fail;
 
+	adreno_gpu->uche_trap_base = 0xffff0000ffff0000ull;
+
 	if (!gpu->aspace) {
 		/* TODO we think it is possible to configure the GPU to
 		 * restrict access to VRAM carveout.  But the required
diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
index ee89db72e36e..caf2c0a7a29f 100644
--- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c
@@ -750,10 +750,10 @@ static int a5xx_hw_init(struct msm_gpu *gpu)
 	gpu_write(gpu, REG_A5XX_UCHE_CACHE_WAYS, 0x02);
 
 	/* Disable L2 bypass in the UCHE */
-	gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_LO, 0xFFFF0000);
-	gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_HI, 0x0001FFFF);
-	gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_LO, 0xFFFF0000);
-	gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_HI, 0x0001FFFF);
+	gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_LO, lower_32_bits(adreno_gpu->uche_trap_base));
+	gpu_write(gpu, REG_A5XX_UCHE_TRAP_BASE_HI, upper_32_bits(adreno_gpu->uche_trap_base));
+	gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_LO, lower_32_bits(adreno_gpu->uche_trap_base));
+	gpu_write(gpu, REG_A5XX_UCHE_WRITE_THRU_BASE_HI, upper_32_bits(adreno_gpu->uche_trap_base));
 
 	/* Set the GMEM VA range (0 to gpu->gmem) */
 	gpu_write(gpu, REG_A5XX_UCHE_GMEM_RANGE_MIN_LO, 0x00100000);
@@ -1805,5 +1805,7 @@ struct msm_gpu *a5xx_gpu_init(struct drm_device *dev)
 	adreno_gpu->ubwc_config.macrotile_mode = 0;
 	adreno_gpu->ubwc_config.ubwc_swizzle = 0x7;
 
+	adreno_gpu->uche_trap_base = 0x0001ffffffff0000ull;
+
 	return gpu;
 }
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
index 019610341df1..0ae29a7c8a4d 100644
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
@@ -1123,12 +1123,12 @@ static int hw_init(struct msm_gpu *gpu)
 
 	/* Disable L2 bypass in the UCHE */
 	if (adreno_is_a7xx(adreno_gpu)) {
-		gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, 0x0001fffffffff000llu);
-		gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, 0x0001fffffffff000llu);
+		gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, adreno_gpu->uche_trap_base);
+		gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, adreno_gpu->uche_trap_base);
 	} else {
-		gpu_write64(gpu, REG_A6XX_UCHE_WRITE_RANGE_MAX, 0x0001ffffffffffc0llu);
-		gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, 0x0001fffffffff000llu);
-		gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, 0x0001fffffffff000llu);
+		gpu_write64(gpu, REG_A6XX_UCHE_WRITE_RANGE_MAX, adreno_gpu->uche_trap_base + 0xfc0);
+		gpu_write64(gpu, REG_A6XX_UCHE_TRAP_BASE, adreno_gpu->uche_trap_base);
+		gpu_write64(gpu, REG_A6XX_UCHE_WRITE_THRU_BASE, adreno_gpu->uche_trap_base);
 	}
 
 	if (!(adreno_is_a650_family(adreno_gpu) ||
@@ -2533,6 +2533,8 @@ struct msm_gpu *a6xx_gpu_init(struct drm_device *dev)
 		}
 	}
 
+	adreno_gpu->uche_trap_base = 0x1fffffffff000ull;
+
 	if (gpu->aspace)
 		msm_mmu_set_fault_handler(gpu->aspace->mmu, gpu,
 				a6xx_fault_handler);
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 9649c0bd0a38..422b5b8b1197 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -386,6 +386,11 @@ int adreno_get_param(struct msm_gpu *gpu, struct msm_file_private *ctx,
 	case MSM_PARAM_MACROTILE_MODE:
 		*value = adreno_gpu->ubwc_config.macrotile_mode;
 		return 0;
+	case MSM_PARAM_UCHE_TRAP_BASE:
+		if (adreno_gpu->uche_trap_base == 0)
+			return UERR(EINVAL, drm, "no uche trap base");
+		*value = adreno_gpu->uche_trap_base;
+		return 0;
 	default:
 		return UERR(EINVAL, drm, "%s: invalid param: %u", gpu->name, param);
 	}
diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
index e71f420f8b3a..9bd38dda4308 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
@@ -253,6 +253,8 @@ struct adreno_gpu {
 	bool gmu_is_wrapper;
 
 	bool has_ray_tracing;
+
+	u64 uche_trap_base;
 };
 #define to_adreno_gpu(x) container_of(x, struct adreno_gpu, base)
 
diff --git a/include/uapi/drm/msm_drm.h b/include/uapi/drm/msm_drm.h
index b916aab80dde..2342cb90857e 100644
--- a/include/uapi/drm/msm_drm.h
+++ b/include/uapi/drm/msm_drm.h
@@ -90,6 +90,7 @@ struct drm_msm_timespec {
 #define MSM_PARAM_RAYTRACING 0x11 /* RO */
 #define MSM_PARAM_UBWC_SWIZZLE 0x12 /* RO */
 #define MSM_PARAM_MACROTILE_MODE 0x13 /* RO */
+#define MSM_PARAM_UCHE_TRAP_BASE 0x14 /* RO */
 
 /* For backwards compat.  The original support for preemption was based on
  * a single ring per priority level so # of priority levels equals the #
-- 
2.46.2



More information about the Freedreno mailing list