Commit edf8afee authored by Lorenzo Bianconi's avatar Lorenzo Bianconi Committed by Jakub Kicinski
Browse files

net: airoha: Compute number of descriptors according to reserved memory size 



In order to not exceed the reserved memory size for hwfd buffers,
compute the number of hwfd buffers/descriptors according to the
reserved memory size and the size of each hwfd buffer (2KB).

Fixes: 3a1ce9e3 ("net: airoha: Add the capability to allocate hwfd buffers via reserved-memory")
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Signed-off-by: default avatarLorenzo Bianconi <lorenzo@kernel.org>
Link: https://patch.msgid.link/20250619-airoha-hw-num-desc-v4-1-49600a9b319a@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent dccf87ea

drivers/net/ethernet/airoha/airoha_eth.c

+12 −9
Original line number Diff line number Diff line
@@ -1065,19 +1065,13 @@ static void airoha_qdma_cleanup_tx_queue(struct airoha_queue *q) 


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];

	dma_addr_t dma_addr;

	const char *name;

	int size, index;

	u32 status;



	size = HW_DSCP_NUM * sizeof(struct airoha_qdma_fwd_desc);

	if (!dmam_alloc_coherent(eth->dev, size, &dma_addr, GFP_KERNEL))

		return -ENOMEM;



	airoha_qdma_wr(qdma, REG_FWD_DSCP_BASE, dma_addr);



	name = devm_kasprintf(eth->dev, GFP_KERNEL, "qdma%d-buf", id);

	if (!name)

		return -ENOMEM;
@@ -1099,8 +1093,12 @@ static int airoha_qdma_init_hfwd_queues(struct airoha_qdma *qdma) 
		rmem = of_reserved_mem_lookup(np);

		of_node_put(np);

		dma_addr = rmem->base;

		/* 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;

	} else {

		size = AIROHA_MAX_PACKET_SIZE * HW_DSCP_NUM;

		size = AIROHA_MAX_PACKET_SIZE * num_desc;

		if (!dmam_alloc_coherent(eth->dev, size, &dma_addr,

					 GFP_KERNEL))

			return -ENOMEM;
@@ -1108,6 +1106,11 @@ static int airoha_qdma_init_hfwd_queues(struct airoha_qdma *qdma) 


	airoha_qdma_wr(qdma, REG_FWD_BUF_BASE, dma_addr);



	size = num_desc * sizeof(struct airoha_qdma_fwd_desc);

	if (!dmam_alloc_coherent(eth->dev, size, &dma_addr, GFP_KERNEL))

		return -ENOMEM;



	airoha_qdma_wr(qdma, REG_FWD_DSCP_BASE, dma_addr);

	airoha_qdma_rmw(qdma, REG_HW_FWD_DSCP_CFG,

			HW_FWD_DSCP_PAYLOAD_SIZE_MASK,

			FIELD_PREP(HW_FWD_DSCP_PAYLOAD_SIZE_MASK, 0));
@@ -1116,7 +1119,7 @@ static int airoha_qdma_init_hfwd_queues(struct airoha_qdma *qdma) 
	airoha_qdma_rmw(qdma, REG_LMGR_INIT_CFG,

			LMGR_INIT_START | LMGR_SRAM_MODE_MASK |

			HW_FWD_DESC_NUM_MASK,

			FIELD_PREP(HW_FWD_DESC_NUM_MASK, HW_DSCP_NUM) |

			FIELD_PREP(HW_FWD_DESC_NUM_MASK, num_desc) |

			LMGR_INIT_START | LMGR_SRAM_MODE_MASK);



	return read_poll_timeout(airoha_qdma_rr, status,