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1// SPDX-License-Identifier: GPL-2.02/*3 * Earthsoft PT3 driver4 *5 * Copyright (C) 2014 Akihiro Tsukada <tskd08@gmail.com>6 */7#include <linux/dma-mapping.h>8#include <linux/kernel.h>9#include <linux/pci.h>10 11#include "pt3.h"12 13#define PT3_ACCESS_UNIT (TS_PACKET_SZ * 128)14#define PT3_BUF_CANARY (0x74)15 16static u32 get_dma_base(int idx)17{18 int i;19 20 i = (idx == 1 || idx == 2) ? 3 - idx : idx;21 return REG_DMA_BASE + 0x18 * i;22}23 24int pt3_stop_dma(struct pt3_adapter *adap)25{26 struct pt3_board *pt3 = adap->dvb_adap.priv;27 u32 base;28 u32 stat;29 int retry;30 31 base = get_dma_base(adap->adap_idx);32 stat = ioread32(pt3->regs[0] + base + OFST_STATUS);33 if (!(stat & 0x01))34 return 0;35 36 iowrite32(0x02, pt3->regs[0] + base + OFST_DMA_CTL);37 for (retry = 0; retry < 5; retry++) {38 stat = ioread32(pt3->regs[0] + base + OFST_STATUS);39 if (!(stat & 0x01))40 return 0;41 msleep(50);42 }43 return -EIO;44}45 46int pt3_start_dma(struct pt3_adapter *adap)47{48 struct pt3_board *pt3 = adap->dvb_adap.priv;49 u32 base = get_dma_base(adap->adap_idx);50 51 iowrite32(0x02, pt3->regs[0] + base + OFST_DMA_CTL);52 iowrite32(lower_32_bits(adap->desc_buf[0].b_addr),53 pt3->regs[0] + base + OFST_DMA_DESC_L);54 iowrite32(upper_32_bits(adap->desc_buf[0].b_addr),55 pt3->regs[0] + base + OFST_DMA_DESC_H);56 iowrite32(0x01, pt3->regs[0] + base + OFST_DMA_CTL);57 return 0;58}59 60 61static u8 *next_unit(struct pt3_adapter *adap, int *idx, int *ofs)62{63 *ofs += PT3_ACCESS_UNIT;64 if (*ofs >= DATA_BUF_SZ) {65 *ofs -= DATA_BUF_SZ;66 (*idx)++;67 if (*idx == adap->num_bufs)68 *idx = 0;69 }70 return &adap->buffer[*idx].data[*ofs];71}72 73int pt3_proc_dma(struct pt3_adapter *adap)74{75 int idx, ofs;76 77 idx = adap->buf_idx;78 ofs = adap->buf_ofs;79 80 if (adap->buffer[idx].data[ofs] == PT3_BUF_CANARY)81 return 0;82 83 while (*next_unit(adap, &idx, &ofs) != PT3_BUF_CANARY) {84 u8 *p;85 86 p = &adap->buffer[adap->buf_idx].data[adap->buf_ofs];87 if (adap->num_discard > 0)88 adap->num_discard--;89 else if (adap->buf_ofs + PT3_ACCESS_UNIT > DATA_BUF_SZ) {90 dvb_dmx_swfilter_packets(&adap->demux, p,91 (DATA_BUF_SZ - adap->buf_ofs) / TS_PACKET_SZ);92 dvb_dmx_swfilter_packets(&adap->demux,93 adap->buffer[idx].data, ofs / TS_PACKET_SZ);94 } else95 dvb_dmx_swfilter_packets(&adap->demux, p,96 PT3_ACCESS_UNIT / TS_PACKET_SZ);97 98 *p = PT3_BUF_CANARY;99 adap->buf_idx = idx;100 adap->buf_ofs = ofs;101 }102 return 0;103}104 105void pt3_init_dmabuf(struct pt3_adapter *adap)106{107 int idx, ofs;108 u8 *p;109 110 idx = 0;111 ofs = 0;112 p = adap->buffer[0].data;113 /* mark the whole buffers as "not written yet" */114 while (idx < adap->num_bufs) {115 p[ofs] = PT3_BUF_CANARY;116 ofs += PT3_ACCESS_UNIT;117 if (ofs >= DATA_BUF_SZ) {118 ofs -= DATA_BUF_SZ;119 idx++;120 p = adap->buffer[idx].data;121 }122 }123 adap->buf_idx = 0;124 adap->buf_ofs = 0;125}126 127void pt3_free_dmabuf(struct pt3_adapter *adap)128{129 struct pt3_board *pt3;130 int i;131 132 pt3 = adap->dvb_adap.priv;133 for (i = 0; i < adap->num_bufs; i++)134 dma_free_coherent(&pt3->pdev->dev, DATA_BUF_SZ,135 adap->buffer[i].data, adap->buffer[i].b_addr);136 adap->num_bufs = 0;137 138 for (i = 0; i < adap->num_desc_bufs; i++)139 dma_free_coherent(&pt3->pdev->dev, PAGE_SIZE,140 adap->desc_buf[i].descs, adap->desc_buf[i].b_addr);141 adap->num_desc_bufs = 0;142}143 144 145int pt3_alloc_dmabuf(struct pt3_adapter *adap)146{147 struct pt3_board *pt3;148 void *p;149 int i, j;150 int idx, ofs;151 int num_desc_bufs;152 dma_addr_t data_addr, desc_addr;153 struct xfer_desc *d;154 155 pt3 = adap->dvb_adap.priv;156 adap->num_bufs = 0;157 adap->num_desc_bufs = 0;158 for (i = 0; i < pt3->num_bufs; i++) {159 p = dma_alloc_coherent(&pt3->pdev->dev, DATA_BUF_SZ,160 &adap->buffer[i].b_addr, GFP_KERNEL);161 if (p == NULL)162 goto failed;163 adap->buffer[i].data = p;164 adap->num_bufs++;165 }166 pt3_init_dmabuf(adap);167 168 /* build circular-linked pointers (xfer_desc) to the data buffers*/169 idx = 0;170 ofs = 0;171 num_desc_bufs =172 DIV_ROUND_UP(adap->num_bufs * DATA_BUF_XFERS, DESCS_IN_PAGE);173 for (i = 0; i < num_desc_bufs; i++) {174 p = dma_alloc_coherent(&pt3->pdev->dev, PAGE_SIZE,175 &desc_addr, GFP_KERNEL);176 if (p == NULL)177 goto failed;178 adap->num_desc_bufs++;179 adap->desc_buf[i].descs = p;180 adap->desc_buf[i].b_addr = desc_addr;181 182 if (i > 0) {183 d = &adap->desc_buf[i - 1].descs[DESCS_IN_PAGE - 1];184 d->next_l = lower_32_bits(desc_addr);185 d->next_h = upper_32_bits(desc_addr);186 }187 for (j = 0; j < DESCS_IN_PAGE; j++) {188 data_addr = adap->buffer[idx].b_addr + ofs;189 d = &adap->desc_buf[i].descs[j];190 d->addr_l = lower_32_bits(data_addr);191 d->addr_h = upper_32_bits(data_addr);192 d->size = DATA_XFER_SZ;193 194 desc_addr += sizeof(struct xfer_desc);195 d->next_l = lower_32_bits(desc_addr);196 d->next_h = upper_32_bits(desc_addr);197 198 ofs += DATA_XFER_SZ;199 if (ofs >= DATA_BUF_SZ) {200 ofs -= DATA_BUF_SZ;201 idx++;202 if (idx >= adap->num_bufs) {203 desc_addr = adap->desc_buf[0].b_addr;204 d->next_l = lower_32_bits(desc_addr);205 d->next_h = upper_32_bits(desc_addr);206 return 0;207 }208 }209 }210 }211 return 0;212 213failed:214 pt3_free_dmabuf(adap);215 return -ENOMEM;216}217