drivers/net/ethernet/apm/xgene-v2/ring.c

Source file repositories/reference/linux-study-clean/drivers/net/ethernet/apm/xgene-v2/ring.c

File Facts

System
Linux kernel
Corpus path
drivers/net/ethernet/apm/xgene-v2/ring.c
Extension
.c
Size
1672 bytes
Lines
70
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Applied Micro X-Gene SoC Ethernet v2 Driver
 *
 * Copyright (c) 2017, Applied Micro Circuits Corporation
 * Author(s): Iyappan Subramanian <isubramanian@apm.com>
 *	      Keyur Chudgar <kchudgar@apm.com>
 */

#include "main.h"

/* create circular linked list of descriptors */
void xge_setup_desc(struct xge_desc_ring *ring)
{
	struct xge_raw_desc *raw_desc;
	dma_addr_t dma_h, next_dma;
	u16 offset;
	int i;

	for (i = 0; i < XGENE_ENET_NUM_DESC; i++) {
		raw_desc = &ring->raw_desc[i];

		offset = (i + 1) & (XGENE_ENET_NUM_DESC - 1);
		next_dma = ring->dma_addr + (offset * XGENE_ENET_DESC_SIZE);

		raw_desc->m0 = cpu_to_le64(SET_BITS(E, 1) |
					   SET_BITS(PKT_SIZE, SLOT_EMPTY));
		dma_h = upper_32_bits(next_dma);
		raw_desc->m1 = cpu_to_le64(SET_BITS(NEXT_DESC_ADDRL, next_dma) |
					   SET_BITS(NEXT_DESC_ADDRH, dma_h));
	}
}

void xge_update_tx_desc_addr(struct xge_pdata *pdata)
{
	struct xge_desc_ring *ring = pdata->tx_ring;
	dma_addr_t dma_addr = ring->dma_addr;

	xge_wr_csr(pdata, DMATXDESCL, dma_addr);
	xge_wr_csr(pdata, DMATXDESCH, upper_32_bits(dma_addr));

	ring->head = 0;
	ring->tail = 0;
}

void xge_update_rx_desc_addr(struct xge_pdata *pdata)
{
	struct xge_desc_ring *ring = pdata->rx_ring;
	dma_addr_t dma_addr = ring->dma_addr;

	xge_wr_csr(pdata, DMARXDESCL, dma_addr);
	xge_wr_csr(pdata, DMARXDESCH, upper_32_bits(dma_addr));

	ring->head = 0;
	ring->tail = 0;
}

void xge_intr_enable(struct xge_pdata *pdata)
{
	u32 data;

	data = RX_PKT_RCVD | TX_PKT_SENT;
	xge_wr_csr(pdata, DMAINTRMASK, data);
}

void xge_intr_disable(struct xge_pdata *pdata)
{
	xge_wr_csr(pdata, DMAINTRMASK, 0);
}

Annotation

Implementation Notes