1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Generic PXA PATA driver 4 * 5 * Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.com> 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/blkdev.h> 11 #include <linux/ata.h> 12 #include <linux/libata.h> 13 #include <linux/platform_device.h> 14 #include <linux/dmaengine.h> 15 #include <linux/slab.h> 16 #include <linux/completion.h> 17 18 #include <scsi/scsi_host.h> 19 20 #include <linux/platform_data/ata-pxa.h> 21 22 #define DRV_NAME "pata_pxa" 23 #define DRV_VERSION "0.1" 24 25 struct pata_pxa_data { 26 struct dma_chan *dma_chan; 27 dma_cookie_t dma_cookie; 28 struct completion dma_done; 29 }; 30 31 /* 32 * DMA interrupt handler. 33 */ 34 static void pxa_ata_dma_irq(void *d) 35 { 36 struct pata_pxa_data *pd = d; 37 enum dma_status status; 38 39 status = dmaengine_tx_status(pd->dma_chan, pd->dma_cookie, NULL); 40 if (status == DMA_ERROR || status == DMA_COMPLETE) 41 complete(&pd->dma_done); 42 } 43 44 /* 45 * Prepare taskfile for submission. 46 */ 47 static enum ata_completion_errors pxa_qc_prep(struct ata_queued_cmd *qc) 48 { 49 struct pata_pxa_data *pd = qc->ap->private_data; 50 struct dma_async_tx_descriptor *tx; 51 enum dma_transfer_direction dir; 52 53 if (!(qc->flags & ATA_QCFLAG_DMAMAP)) 54 return AC_ERR_OK; 55 56 dir = (qc->dma_dir == DMA_TO_DEVICE ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM); 57 tx = dmaengine_prep_slave_sg(pd->dma_chan, qc->sg, qc->n_elem, dir, 58 DMA_PREP_INTERRUPT); 59 if (!tx) { 60 ata_dev_err(qc->dev, "prep_slave_sg() failed\n"); 61 return AC_ERR_OK; 62 } 63 tx->callback = pxa_ata_dma_irq; 64 tx->callback_param = pd; 65 pd->dma_cookie = dmaengine_submit(tx); 66 67 return AC_ERR_OK; 68 } 69 70 /* 71 * Configure the DMA controller, load the DMA descriptors, but don't start the 72 * DMA controller yet. Only issue the ATA command. 73 */ 74 static void pxa_bmdma_setup(struct ata_queued_cmd *qc) 75 { 76 qc->ap->ops->sff_exec_command(qc->ap, &qc->tf); 77 } 78 79 /* 80 * Execute the DMA transfer. 81 */ 82 static void pxa_bmdma_start(struct ata_queued_cmd *qc) 83 { 84 struct pata_pxa_data *pd = qc->ap->private_data; 85 init_completion(&pd->dma_done); 86 dma_async_issue_pending(pd->dma_chan); 87 } 88 89 /* 90 * Wait until the DMA transfer completes, then stop the DMA controller. 91 */ 92 static void pxa_bmdma_stop(struct ata_queued_cmd *qc) 93 { 94 struct pata_pxa_data *pd = qc->ap->private_data; 95 enum dma_status status; 96 97 status = dmaengine_tx_status(pd->dma_chan, pd->dma_cookie, NULL); 98 if (status != DMA_ERROR && status != DMA_COMPLETE && 99 wait_for_completion_timeout(&pd->dma_done, HZ)) 100 ata_dev_err(qc->dev, "Timeout waiting for DMA completion!"); 101 102 dmaengine_terminate_all(pd->dma_chan); 103 } 104 105 /* 106 * Read DMA status. The bmdma_stop() will take care of properly finishing the 107 * DMA transfer so we always have DMA-complete interrupt here. 108 */ 109 static unsigned char pxa_bmdma_status(struct ata_port *ap) 110 { 111 struct pata_pxa_data *pd = ap->private_data; 112 unsigned char ret = ATA_DMA_INTR; 113 struct dma_tx_state state; 114 enum dma_status status; 115 116 status = dmaengine_tx_status(pd->dma_chan, pd->dma_cookie, &state); 117 if (status != DMA_COMPLETE) 118 ret |= ATA_DMA_ERR; 119 120 return ret; 121 } 122 123 /* 124 * No IRQ register present so we do nothing. 125 */ 126 static void pxa_irq_clear(struct ata_port *ap) 127 { 128 } 129 130 /* 131 * Check for ATAPI DMA. ATAPI DMA is unsupported by this driver. It's still 132 * unclear why ATAPI has DMA issues. 133 */ 134 static int pxa_check_atapi_dma(struct ata_queued_cmd *qc) 135 { 136 return -EOPNOTSUPP; 137 } 138 139 static const struct scsi_host_template pxa_ata_sht = { 140 ATA_BMDMA_SHT(DRV_NAME), 141 }; 142 143 static struct ata_port_operations pxa_ata_port_ops = { 144 .inherits = &ata_bmdma_port_ops, 145 .cable_detect = ata_cable_40wire, 146 147 .bmdma_setup = pxa_bmdma_setup, 148 .bmdma_start = pxa_bmdma_start, 149 .bmdma_stop = pxa_bmdma_stop, 150 .bmdma_status = pxa_bmdma_status, 151 152 .check_atapi_dma = pxa_check_atapi_dma, 153 154 .sff_irq_clear = pxa_irq_clear, 155 156 .qc_prep = pxa_qc_prep, 157 }; 158 159 static int pxa_ata_probe(struct platform_device *pdev) 160 { 161 struct ata_host *host; 162 struct ata_port *ap; 163 struct pata_pxa_data *data; 164 struct resource *cmd_res; 165 struct resource *ctl_res; 166 struct resource *dma_res; 167 struct pata_pxa_pdata *pdata = dev_get_platdata(&pdev->dev); 168 struct dma_slave_config config; 169 int ret = 0; 170 int irq; 171 172 /* 173 * Resource validation, three resources are needed: 174 * - CMD port base address 175 * - CTL port base address 176 * - DMA port base address 177 * - IRQ pin 178 */ 179 if (pdev->num_resources != 4) { 180 dev_err(&pdev->dev, "invalid number of resources\n"); 181 return -EINVAL; 182 } 183 184 /* 185 * CMD port base address 186 */ 187 cmd_res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 188 if (unlikely(cmd_res == NULL)) 189 return -EINVAL; 190 191 /* 192 * CTL port base address 193 */ 194 ctl_res = platform_get_resource(pdev, IORESOURCE_MEM, 1); 195 if (unlikely(ctl_res == NULL)) 196 return -EINVAL; 197 198 /* 199 * DMA port base address 200 */ 201 dma_res = platform_get_resource(pdev, IORESOURCE_DMA, 0); 202 if (unlikely(dma_res == NULL)) 203 return -EINVAL; 204 205 /* 206 * IRQ pin 207 */ 208 irq = platform_get_irq(pdev, 0); 209 if (irq < 0) 210 return irq; 211 212 /* 213 * Allocate the host 214 */ 215 host = ata_host_alloc(&pdev->dev, 1); 216 if (!host) 217 return -ENOMEM; 218 219 ap = host->ports[0]; 220 ap->ops = &pxa_ata_port_ops; 221 ap->pio_mask = ATA_PIO4; 222 ap->mwdma_mask = ATA_MWDMA2; 223 224 ap->ioaddr.cmd_addr = devm_ioremap(&pdev->dev, cmd_res->start, 225 resource_size(cmd_res)); 226 ap->ioaddr.ctl_addr = devm_ioremap(&pdev->dev, ctl_res->start, 227 resource_size(ctl_res)); 228 ap->ioaddr.bmdma_addr = devm_ioremap(&pdev->dev, dma_res->start, 229 resource_size(dma_res)); 230 231 /* 232 * Adjust register offsets 233 */ 234 ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr; 235 ap->ioaddr.data_addr = ap->ioaddr.cmd_addr + 236 (ATA_REG_DATA << pdata->reg_shift); 237 ap->ioaddr.error_addr = ap->ioaddr.cmd_addr + 238 (ATA_REG_ERR << pdata->reg_shift); 239 ap->ioaddr.feature_addr = ap->ioaddr.cmd_addr + 240 (ATA_REG_FEATURE << pdata->reg_shift); 241 ap->ioaddr.nsect_addr = ap->ioaddr.cmd_addr + 242 (ATA_REG_NSECT << pdata->reg_shift); 243 ap->ioaddr.lbal_addr = ap->ioaddr.cmd_addr + 244 (ATA_REG_LBAL << pdata->reg_shift); 245 ap->ioaddr.lbam_addr = ap->ioaddr.cmd_addr + 246 (ATA_REG_LBAM << pdata->reg_shift); 247 ap->ioaddr.lbah_addr = ap->ioaddr.cmd_addr + 248 (ATA_REG_LBAH << pdata->reg_shift); 249 ap->ioaddr.device_addr = ap->ioaddr.cmd_addr + 250 (ATA_REG_DEVICE << pdata->reg_shift); 251 ap->ioaddr.status_addr = ap->ioaddr.cmd_addr + 252 (ATA_REG_STATUS << pdata->reg_shift); 253 ap->ioaddr.command_addr = ap->ioaddr.cmd_addr + 254 (ATA_REG_CMD << pdata->reg_shift); 255 256 /* 257 * Allocate and load driver's internal data structure 258 */ 259 data = devm_kzalloc(&pdev->dev, sizeof(struct pata_pxa_data), 260 GFP_KERNEL); 261 if (!data) 262 return -ENOMEM; 263 264 ap->private_data = data; 265 266 memset(&config, 0, sizeof(config)); 267 config.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; 268 config.dst_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES; 269 config.src_addr = dma_res->start; 270 config.dst_addr = dma_res->start; 271 config.src_maxburst = 32; 272 config.dst_maxburst = 32; 273 274 /* 275 * Request the DMA channel 276 */ 277 data->dma_chan = 278 dma_request_slave_channel(&pdev->dev, "data"); 279 if (!data->dma_chan) 280 return -EBUSY; 281 ret = dmaengine_slave_config(data->dma_chan, &config); 282 if (ret < 0) { 283 dev_err(&pdev->dev, "dma configuration failed: %d\n", ret); 284 return ret; 285 } 286 287 /* 288 * Activate the ATA host 289 */ 290 ret = ata_host_activate(host, irq, ata_sff_interrupt, 291 pdata->irq_flags, &pxa_ata_sht); 292 if (ret) 293 dma_release_channel(data->dma_chan); 294 295 return ret; 296 } 297 298 static void pxa_ata_remove(struct platform_device *pdev) 299 { 300 struct ata_host *host = platform_get_drvdata(pdev); 301 struct pata_pxa_data *data = host->ports[0]->private_data; 302 303 dma_release_channel(data->dma_chan); 304 305 ata_host_detach(host); 306 } 307 308 static struct platform_driver pxa_ata_driver = { 309 .probe = pxa_ata_probe, 310 .remove_new = pxa_ata_remove, 311 .driver = { 312 .name = DRV_NAME, 313 }, 314 }; 315 316 module_platform_driver(pxa_ata_driver); 317 318 MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>"); 319 MODULE_DESCRIPTION("DMA-capable driver for PATA on PXA CPU"); 320 MODULE_LICENSE("GPL"); 321 MODULE_VERSION(DRV_VERSION); 322 MODULE_ALIAS("platform:" DRV_NAME); 323