124 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2021-2022 Digiteq Automotive4 * author: Martin Tuma <martin.tuma@digiteqautomotive.com>5 *6 * This module handles the DMA transfers. A standard dmaengine API as provided7 * by the XDMA module is used.8 */9 10#include <linux/pci.h>11#include <linux/dma-direction.h>12#include "mgb4_core.h"13#include "mgb4_dma.h"14 15static void chan_irq(void *param)16{17 struct mgb4_dma_channel *chan = param;18 19 complete(&chan->req_compl);20}21 22int mgb4_dma_transfer(struct mgb4_dev *mgbdev, u32 channel, bool write,23 u64 paddr, struct sg_table *sgt)24{25 struct dma_slave_config cfg;26 struct mgb4_dma_channel *chan;27 struct dma_async_tx_descriptor *tx;28 struct pci_dev *pdev = mgbdev->pdev;29 int ret;30 31 memset(&cfg, 0, sizeof(cfg));32 33 if (write) {34 cfg.direction = DMA_MEM_TO_DEV;35 cfg.dst_addr = paddr;36 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;37 chan = &mgbdev->h2c_chan[channel];38 } else {39 cfg.direction = DMA_DEV_TO_MEM;40 cfg.src_addr = paddr;41 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;42 chan = &mgbdev->c2h_chan[channel];43 }44 45 ret = dmaengine_slave_config(chan->chan, &cfg);46 if (ret) {47 dev_err(&pdev->dev, "failed to config dma: %d\n", ret);48 return ret;49 }50 51 tx = dmaengine_prep_slave_sg(chan->chan, sgt->sgl, sgt->nents,52 cfg.direction, 0);53 if (!tx) {54 dev_err(&pdev->dev, "failed to prep slave sg\n");55 return -EIO;56 }57 58 tx->callback = chan_irq;59 tx->callback_param = chan;60 61 ret = dma_submit_error(dmaengine_submit(tx));62 if (ret) {63 dev_err(&pdev->dev, "failed to submit sg\n");64 return -EIO;65 }66 67 dma_async_issue_pending(chan->chan);68 69 if (!wait_for_completion_timeout(&chan->req_compl,70 msecs_to_jiffies(10000))) {71 dev_err(&pdev->dev, "dma timeout\n");72 dmaengine_terminate_sync(chan->chan);73 return -EIO;74 }75 76 return 0;77}78 79int mgb4_dma_channel_init(struct mgb4_dev *mgbdev)80{81 int i, ret;82 char name[16];83 struct pci_dev *pdev = mgbdev->pdev;84 85 for (i = 0; i < MGB4_VIN_DEVICES; i++) {86 sprintf(name, "c2h%d", i);87 mgbdev->c2h_chan[i].chan = dma_request_chan(&pdev->dev, name);88 if (IS_ERR(mgbdev->c2h_chan[i].chan)) {89 dev_err(&pdev->dev, "failed to initialize %s", name);90 ret = PTR_ERR(mgbdev->c2h_chan[i].chan);91 mgbdev->c2h_chan[i].chan = NULL;92 return ret;93 }94 init_completion(&mgbdev->c2h_chan[i].req_compl);95 }96 for (i = 0; i < MGB4_VOUT_DEVICES; i++) {97 sprintf(name, "h2c%d", i);98 mgbdev->h2c_chan[i].chan = dma_request_chan(&pdev->dev, name);99 if (IS_ERR(mgbdev->h2c_chan[i].chan)) {100 dev_err(&pdev->dev, "failed to initialize %s", name);101 ret = PTR_ERR(mgbdev->h2c_chan[i].chan);102 mgbdev->h2c_chan[i].chan = NULL;103 return ret;104 }105 init_completion(&mgbdev->h2c_chan[i].req_compl);106 }107 108 return 0;109}110 111void mgb4_dma_channel_free(struct mgb4_dev *mgbdev)112{113 int i;114 115 for (i = 0; i < MGB4_VIN_DEVICES; i++) {116 if (mgbdev->c2h_chan[i].chan)117 dma_release_channel(mgbdev->c2h_chan[i].chan);118 }119 for (i = 0; i < MGB4_VOUT_DEVICES; i++) {120 if (mgbdev->h2c_chan[i].chan)121 dma_release_channel(mgbdev->h2c_chan[i].chan);122 }123}124