[PATCH net v3 2/2] net: airoha: Differentiate hwfd buffer size for QDMA0 and QDMA1

[Lorenzo Bianconi]

In oreder to reduce the required hwfd buffers queue size for QDMA1,
differentiate hwfd buffer size for QDMA0 and QDMA1 and use 2KB for QDMA0
and 1KB for QDMA1.

Signed-off-by: Lorenzo Bianconi <lorenzo at kernel.org>
---
 drivers/net/ethernet/airoha/airoha_eth.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index 1b7fd7ee0cbf3e1f7717110c70e9c5183fdd93d4..06dea3a13e77ce11f35dbd36966a34c5ef229c11 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -1068,14 +1068,15 @@ static int airoha_qdma_init_hfwd_queues(struct airoha_qdma *qdma)
 	int size, index, num_desc = HW_DSCP_NUM;
 	struct airoha_eth *eth = qdma->eth;
 	int id = qdma - &eth->qdma[0];
+	u32 status, buf_size;
 	dma_addr_t dma_addr;
 	const char *name;
-	u32 status;
 
 	name = devm_kasprintf(eth->dev, GFP_KERNEL, "qdma%d-buf", id);
 	if (!name)
 		return -ENOMEM;
 
+	buf_size = id ? AIROHA_MAX_PACKET_SIZE / 2 : AIROHA_MAX_PACKET_SIZE;
 	index = of_property_match_string(eth->dev->of_node,
 					 "memory-region-names", name);
 	if (index >= 0) {
@@ -1096,9 +1097,9 @@ static int airoha_qdma_init_hfwd_queues(struct airoha_qdma *qdma)
 		/* Compute the number of hw descriptors according to the
 		 * reserved memory size and the payload buffer size
 		 */
-		num_desc = rmem->size / AIROHA_MAX_PACKET_SIZE;
+		num_desc = div_u64(rmem->size, buf_size);
 	} else {
-		size = AIROHA_MAX_PACKET_SIZE * num_desc;
+		size = buf_size * num_desc;
 		if (!dmam_alloc_coherent(eth->dev, size, &dma_addr,
 					 GFP_KERNEL))
 			return -ENOMEM;
@@ -1111,9 +1112,10 @@ static int airoha_qdma_init_hfwd_queues(struct airoha_qdma *qdma)
 		return -ENOMEM;
 
 	airoha_qdma_wr(qdma, REG_FWD_DSCP_BASE, dma_addr);
+	/* QDMA0: 2KB. QDMA1: 1KB */
 	airoha_qdma_rmw(qdma, REG_HW_FWD_DSCP_CFG,
 			HW_FWD_DSCP_PAYLOAD_SIZE_MASK,
-			FIELD_PREP(HW_FWD_DSCP_PAYLOAD_SIZE_MASK, 0));
+			FIELD_PREP(HW_FWD_DSCP_PAYLOAD_SIZE_MASK, !!id));
 	airoha_qdma_rmw(qdma, REG_FWD_DSCP_LOW_THR, FWD_DSCP_LOW_THR_MASK,
 			FIELD_PREP(FWD_DSCP_LOW_THR_MASK, 128));
 	airoha_qdma_rmw(qdma, REG_LMGR_INIT_CFG,

-- 
2.49.0