[PATCH 11/11] accel: ethosu: Validate OFM transpose

[Rob Herring (Arm)]

U85 OFM dimensions are specified before transposition, while
tile bases and strides address the transposed feature map. Permute
the output endpoint before validating its tile and stride accesses.

Allow the defined U85 transpose encodings and reject the two
reserved encodings.

Assisted-by: LLM
Signed-off-by: Rob Herring (Arm) <robh@xxxxxxxxxx>
---
 drivers/accel/ethosu/ethosu_device.h |  1 +
 drivers/accel/ethosu/ethosu_gem.c    | 58 ++++++++++++++++++++++++++++++++++--
 2 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/drivers/accel/ethosu/ethosu_device.h b/drivers/accel/ethosu/ethosu_device.h
index c330048dbcca..1731c43aa045 100644
--- a/drivers/accel/ethosu/ethosu_device.h
+++ b/drivers/accel/ethosu/ethosu_device.h
@@ -87,6 +87,7 @@ struct gen_pool;
 #define PMU_EV_TYPE_IDLE	0x20
 
 #define NPU_DMA_REGION_INDEX_MODE	BIT(11)
+#define NPU_OFM_TRANSPOSE_MASK		GENMASK(13, 11)
 
 enum ethosu_cmds {
 	NPU_OP_STOP = 0x0,
diff --git a/drivers/accel/ethosu/ethosu_gem.c b/drivers/accel/ethosu/ethosu_gem.c
index a042e650f626..ad36fb8b3b30 100644
--- a/drivers/accel/ethosu/ethosu_gem.c
+++ b/drivers/accel/ethosu/ethosu_gem.c
@@ -199,6 +199,52 @@ static bool feat_matrix_chained(struct ethosu_device *edev, struct feat_matrix *
 	return !ethosu_is_u65(edev) && storage == 2;
 }
 
+static int feat_matrix_permute(struct ethosu_device *edev,
+			       struct feat_matrix *fm, u32 *x, u32 *y,
+			       u32 *c, bool ofm)
+{
+	u32 width = *x;
+	u32 height = *y;
+	u32 depth = *c;
+	u32 transpose;
+
+	if (ethosu_is_u65(edev) || !ofm)
+		return 0;
+
+	transpose = FIELD_GET(NPU_OFM_TRANSPOSE_MASK, fm->precision);
+
+	switch (transpose) {
+	case 0: /* HWC */
+		break;
+	case 1: /* WHC */
+		*x = height;
+		*y = width;
+		break;
+	case 2: /* HCW */
+		*x = depth;
+		*c = width;
+		break;
+	case 3: /* WCH */
+		*x = depth;
+		*y = width;
+		*c = height;
+		break;
+	case 6: /* CHW */
+		*x = height;
+		*y = depth;
+		*c = width;
+		break;
+	case 7: /* CWH */
+		*y = depth;
+		*c = height;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static u64 feat_matrix_length(struct ethosu_device *edev,
 			      struct ethosu_validated_cmdstream_info *info,
 			      struct feat_matrix *fm,
@@ -283,6 +329,9 @@ static int feat_matrix_size(struct ethosu_device *edev,
 	int ret;
 
 	*max_len = 0;
+	ret = feat_matrix_permute(edev, fm, &x, &y, &c, ofm);
+	if (ret)
+		return ret;
 
 	if (ethosu_is_u65(edev) || storage == 0) {
 		for (int xi = 0; xi < 2; xi++) {
@@ -641,8 +690,13 @@ static int ethosu_gem_cmdstream_copy_and_validate(struct drm_device *ddev,
 		case NPU_SET_OFM_PRECISION:
 			if (((param >> 6) & 0x3) > 1)
 				return -EINVAL;
-			if (!ethosu_is_u65(edev) && (param & GENMASK(13, 11)))
-				return -EINVAL;
+			if (!ethosu_is_u65(edev)) {
+				switch (FIELD_GET(NPU_OFM_TRANSPOSE_MASK, param)) {
+				case 4:
+				case 5:
+					return -EINVAL;
+				}
+			}
 			st.ofm.precision = param;
 			break;
 		case NPU_SET_OFM_REGION:

-- 
2.53.0