[PATCH v4 24/31] accel: ethosu: Validate accumulator input

["Rob Herring (Arm)" <robh@kernel.org>]

The U85 ACC_FORMAT command can select IFM2 as the accumulator
input. This is used by null-pool operations and can also be used
by convolution. Track this selection and validate the IFM2 feature
map against the OFM extent before submitting the operation.

Fixes: 5a5e9c0228e6 ("accel: Add Arm Ethos-U NPU driver")
Cc: stable@vger.kernel.org
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
---
v4:
 - Accumulator input should not be checked for elementwise ops

v2:
 - new patch
---
 drivers/accel/ethosu/ethosu_device.h |  4 ++++
 drivers/accel/ethosu/ethosu_gem.c    | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/drivers/accel/ethosu/ethosu_device.h b/drivers/accel/ethosu/ethosu_device.h
index 80cba318f773..d3df6720085d 100644
--- a/drivers/accel/ethosu/ethosu_device.h
+++ b/drivers/accel/ethosu/ethosu_device.h
@@ -127,6 +127,7 @@ enum ethosu_cmds {
 	NPU_SET_KERNEL_WIDTH_M1 = 0x120,
 	NPU_SET_KERNEL_HEIGHT_M1 = 0x121,
 	NPU_SET_KERNEL_STRIDE = 0x122,
+	NPU_SET_ACC_FORMAT = 0x124,
 	NPU_SET_WEIGHT_REGION = 0x128,
 	NPU_SET_SCALE_REGION = 0x129,
 	NPU_SET_DMA0_SRC_REGION = 0x130,
@@ -181,6 +182,9 @@ enum ethosu_cmds {
 	NPU_SET_WEIGHT3_LENGTH = 0x4095,
 };
 
+#define NPU_ACC_FORMAT_INPUT_MASK	GENMASK(5, 4)
+#define NPU_ACC_INPUT_IFM2		2
+
 #define ETHOSU_SRAM_REGION	2	/* Matching Vela compiler */
 
 struct ethosu_perfmon;
diff --git a/drivers/accel/ethosu/ethosu_gem.c b/drivers/accel/ethosu/ethosu_gem.c
index 15a4cab1b286..406e1c07246d 100644
--- a/drivers/accel/ethosu/ethosu_gem.c
+++ b/drivers/accel/ethosu/ethosu_gem.c
@@ -155,6 +155,7 @@ struct feat_matrix {
 struct cmd_state {
 	DECLARE_BITMAP(cmd0, NPU_CMD0_REGS);
 	DECLARE_BITMAP(cmd1, NPU_CMD1_REGS);
+	bool acc_input_ifm2;
 	struct dma_state dma;
 	struct buffer scale[2];
 	struct buffer weight[4];
@@ -534,6 +535,28 @@ static int feat_matrix_size(struct ethosu_device *edev,
 					  max_len);
 }
 
+static int
+calc_acc_input_size(struct drm_device *ddev,
+		    struct ethosu_validated_cmdstream_info *info,
+		    struct cmd_state *st)
+{
+	struct ethosu_device *edev = to_ethosu_device(ddev);
+	u64 len;
+	int ret;
+
+	if (!st->acc_input_ifm2)
+		return 0;
+
+	/* The accumulator has one input value for each OFM element. */
+	ret = feat_matrix_size(edev, info, st, &st->ifm2,
+			       FEAT_MATRIX_IFM2, st->ofm.width,
+			       st->ofm.height[2], st->ofm.depth, false, &len);
+	dev_dbg(ddev->dev, "ACC IFM2:%d:0x%llx-0x%llx\n",
+		st->ifm2.region, st->ifm2.base[0], len);
+
+	return ret;
+}
+
 static int buffer_size(struct ethosu_validated_cmdstream_info *info,
 		       struct cmd_state *st, struct buffer *buf, s8 region,
 		       u16 region_cmd, u16 base_cmd, u16 length_cmd, bool optional)
@@ -655,6 +678,9 @@ static int calc_sizes(struct drm_device *ddev,
 			       true, &len);
 	dev_dbg(ddev->dev, "op %d: OFM:%d:0x%llx-0x%llx\n",
 		op, st->ofm.region, st->ofm.base[0], len);
+	if (ret)
+		return ret;
+	ret = calc_acc_input_size(ddev, info, st);
 	if (ret)
 		return ret;
 	if (!feat_matrix_chained(edev, &st->ofm))
@@ -842,6 +868,15 @@ static int ethosu_gem_cmdstream_copy_and_validate(struct drm_device *ddev,
 		case NPU_SET_KERNEL_STRIDE:
 			st.ifm.stride_kernel = param;
 			break;
+		case NPU_SET_ACC_FORMAT:
+			if (!ethosu_is_u65(edev)) {
+				u32 acc_input = FIELD_GET(NPU_ACC_FORMAT_INPUT_MASK, param);
+
+				if (acc_input > NPU_ACC_INPUT_IFM2)
+					return -EINVAL;
+				st.acc_input_ifm2 = acc_input == NPU_ACC_INPUT_IFM2;
+			}
+			break;
 		case NPU_SET_IFM_PAD_TOP:
 			st.ifm.pad_top = param & 0x7f;
 			break;

-- 
2.53.0