1 /* 2 * pata_sl82c105.c - SL82C105 PATA for new ATA layer 3 * (C) 2005 Red Hat Inc 4 * Alan Cox <alan@redhat.com> 5 * 6 * Based in part on linux/drivers/ide/pci/sl82c105.c 7 * SL82C105/Winbond 553 IDE driver 8 * 9 * and in part on the documentation and errata sheet 10 * 11 * 12 * Note: The controller like many controllers has shared timings for 13 * PIO and DMA. We thus flip to the DMA timings in dma_start and flip back 14 * in the dma_stop function. Thus we actually don't need a set_dmamode 15 * method as the PIO method is always called and will set the right PIO 16 * timing parameters. 17 */ 18 19 #include <linux/kernel.h> 20 #include <linux/module.h> 21 #include <linux/pci.h> 22 #include <linux/init.h> 23 #include <linux/blkdev.h> 24 #include <linux/delay.h> 25 #include <scsi/scsi_host.h> 26 #include <linux/libata.h> 27 28 #define DRV_NAME "pata_sl82c105" 29 #define DRV_VERSION "0.3.3" 30 31 enum { 32 /* 33 * SL82C105 PCI config register 0x40 bits. 34 */ 35 CTRL_IDE_IRQB = (1 << 30), 36 CTRL_IDE_IRQA = (1 << 28), 37 CTRL_LEGIRQ = (1 << 11), 38 CTRL_P1F16 = (1 << 5), 39 CTRL_P1EN = (1 << 4), 40 CTRL_P0F16 = (1 << 1), 41 CTRL_P0EN = (1 << 0) 42 }; 43 44 /** 45 * sl82c105_pre_reset - probe begin 46 * @link: ATA link 47 * @deadline: deadline jiffies for the operation 48 * 49 * Set up cable type and use generic probe init 50 */ 51 52 static int sl82c105_pre_reset(struct ata_link *link, unsigned long deadline) 53 { 54 static const struct pci_bits sl82c105_enable_bits[] = { 55 { 0x40, 1, 0x01, 0x01 }, 56 { 0x40, 1, 0x10, 0x10 } 57 }; 58 struct ata_port *ap = link->ap; 59 struct pci_dev *pdev = to_pci_dev(ap->host->dev); 60 61 if (ap->port_no && !pci_test_config_bits(pdev, &sl82c105_enable_bits[ap->port_no])) 62 return -ENOENT; 63 return ata_sff_prereset(link, deadline); 64 } 65 66 67 /** 68 * sl82c105_configure_piomode - set chip PIO timing 69 * @ap: ATA interface 70 * @adev: ATA device 71 * @pio: PIO mode 72 * 73 * Called to do the PIO mode setup. Our timing registers are shared 74 * so a configure_dmamode call will undo any work we do here and vice 75 * versa 76 */ 77 78 static void sl82c105_configure_piomode(struct ata_port *ap, struct ata_device *adev, int pio) 79 { 80 struct pci_dev *pdev = to_pci_dev(ap->host->dev); 81 static u16 pio_timing[5] = { 82 0x50D, 0x407, 0x304, 0x242, 0x240 83 }; 84 u16 dummy; 85 int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno); 86 87 pci_write_config_word(pdev, timing, pio_timing[pio]); 88 /* Can we lose this oddity of the old driver */ 89 pci_read_config_word(pdev, timing, &dummy); 90 } 91 92 /** 93 * sl82c105_set_piomode - set initial PIO mode data 94 * @ap: ATA interface 95 * @adev: ATA device 96 * 97 * Called to do the PIO mode setup. Our timing registers are shared 98 * but we want to set the PIO timing by default. 99 */ 100 101 static void sl82c105_set_piomode(struct ata_port *ap, struct ata_device *adev) 102 { 103 sl82c105_configure_piomode(ap, adev, adev->pio_mode - XFER_PIO_0); 104 } 105 106 /** 107 * sl82c105_configure_dmamode - set DMA mode in chip 108 * @ap: ATA interface 109 * @adev: ATA device 110 * 111 * Load DMA cycle times into the chip ready for a DMA transfer 112 * to occur. 113 */ 114 115 static void sl82c105_configure_dmamode(struct ata_port *ap, struct ata_device *adev) 116 { 117 struct pci_dev *pdev = to_pci_dev(ap->host->dev); 118 static u16 dma_timing[3] = { 119 0x707, 0x201, 0x200 120 }; 121 u16 dummy; 122 int timing = 0x44 + (8 * ap->port_no) + (4 * adev->devno); 123 int dma = adev->dma_mode - XFER_MW_DMA_0; 124 125 pci_write_config_word(pdev, timing, dma_timing[dma]); 126 /* Can we lose this oddity of the old driver */ 127 pci_read_config_word(pdev, timing, &dummy); 128 } 129 130 /** 131 * sl82c105_reset_engine - Reset the DMA engine 132 * @ap: ATA interface 133 * 134 * The sl82c105 has some serious problems with the DMA engine 135 * when transfers don't run as expected or ATAPI is used. The 136 * recommended fix is to reset the engine each use using a chip 137 * test register. 138 */ 139 140 static void sl82c105_reset_engine(struct ata_port *ap) 141 { 142 struct pci_dev *pdev = to_pci_dev(ap->host->dev); 143 u16 val; 144 145 pci_read_config_word(pdev, 0x7E, &val); 146 pci_write_config_word(pdev, 0x7E, val | 4); 147 pci_write_config_word(pdev, 0x7E, val & ~4); 148 } 149 150 /** 151 * sl82c105_bmdma_start - DMA engine begin 152 * @qc: ATA command 153 * 154 * Reset the DMA engine each use as recommended by the errata 155 * document. 156 * 157 * FIXME: if we switch clock at BMDMA start/end we might get better 158 * PIO performance on DMA capable devices. 159 */ 160 161 static void sl82c105_bmdma_start(struct ata_queued_cmd *qc) 162 { 163 struct ata_port *ap = qc->ap; 164 165 udelay(100); 166 sl82c105_reset_engine(ap); 167 udelay(100); 168 169 /* Set the clocks for DMA */ 170 sl82c105_configure_dmamode(ap, qc->dev); 171 /* Activate DMA */ 172 ata_bmdma_start(qc); 173 } 174 175 /** 176 * sl82c105_bmdma_end - DMA engine stop 177 * @qc: ATA command 178 * 179 * Reset the DMA engine each use as recommended by the errata 180 * document. 181 * 182 * This function is also called to turn off DMA when a timeout occurs 183 * during DMA operation. In both cases we need to reset the engine, 184 * so no actual eng_timeout handler is required. 185 * 186 * We assume bmdma_stop is always called if bmdma_start as called. If 187 * not then we may need to wrap qc_issue. 188 */ 189 190 static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc) 191 { 192 struct ata_port *ap = qc->ap; 193 194 ata_bmdma_stop(qc); 195 sl82c105_reset_engine(ap); 196 udelay(100); 197 198 /* This will redo the initial setup of the DMA device to matching 199 PIO timings */ 200 sl82c105_set_piomode(ap, qc->dev); 201 } 202 203 /** 204 * sl82c105_qc_defer - implement serialization 205 * @qc: command 206 * 207 * We must issue one command per host not per channel because 208 * of the reset bug. 209 * 210 * Q: is the scsi host lock sufficient ? 211 */ 212 213 static int sl82c105_qc_defer(struct ata_queued_cmd *qc) 214 { 215 struct ata_host *host = qc->ap->host; 216 struct ata_port *alt = host->ports[1 ^ qc->ap->port_no]; 217 int rc; 218 219 /* First apply the usual rules */ 220 rc = ata_std_qc_defer(qc); 221 if (rc != 0) 222 return rc; 223 224 /* Now apply serialization rules. Only allow a command if the 225 other channel state machine is idle */ 226 if (alt && alt->qc_active) 227 return ATA_DEFER_PORT; 228 return 0; 229 } 230 231 static struct scsi_host_template sl82c105_sht = { 232 ATA_BMDMA_SHT(DRV_NAME), 233 }; 234 235 static struct ata_port_operations sl82c105_port_ops = { 236 .inherits = &ata_bmdma_port_ops, 237 .qc_defer = sl82c105_qc_defer, 238 .bmdma_start = sl82c105_bmdma_start, 239 .bmdma_stop = sl82c105_bmdma_stop, 240 .cable_detect = ata_cable_40wire, 241 .set_piomode = sl82c105_set_piomode, 242 .prereset = sl82c105_pre_reset, 243 }; 244 245 /** 246 * sl82c105_bridge_revision - find bridge version 247 * @pdev: PCI device for the ATA function 248 * 249 * Locates the PCI bridge associated with the ATA function and 250 * providing it is a Winbond 553 reports the revision. If it cannot 251 * find a revision or the right device it returns -1 252 */ 253 254 static int sl82c105_bridge_revision(struct pci_dev *pdev) 255 { 256 struct pci_dev *bridge; 257 258 /* 259 * The bridge should be part of the same device, but function 0. 260 */ 261 bridge = pci_get_slot(pdev->bus, 262 PCI_DEVFN(PCI_SLOT(pdev->devfn), 0)); 263 if (!bridge) 264 return -1; 265 266 /* 267 * Make sure it is a Winbond 553 and is an ISA bridge. 268 */ 269 if (bridge->vendor != PCI_VENDOR_ID_WINBOND || 270 bridge->device != PCI_DEVICE_ID_WINBOND_83C553 || 271 bridge->class >> 8 != PCI_CLASS_BRIDGE_ISA) { 272 pci_dev_put(bridge); 273 return -1; 274 } 275 /* 276 * We need to find function 0's revision, not function 1 277 */ 278 pci_dev_put(bridge); 279 return bridge->revision; 280 } 281 282 283 static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id) 284 { 285 static const struct ata_port_info info_dma = { 286 .flags = ATA_FLAG_SLAVE_POSS, 287 .pio_mask = 0x1f, 288 .mwdma_mask = 0x07, 289 .port_ops = &sl82c105_port_ops 290 }; 291 static const struct ata_port_info info_early = { 292 .flags = ATA_FLAG_SLAVE_POSS, 293 .pio_mask = 0x1f, 294 .port_ops = &sl82c105_port_ops 295 }; 296 /* for now use only the first port */ 297 const struct ata_port_info *ppi[] = { &info_early, 298 NULL }; 299 u32 val; 300 int rev; 301 int rc; 302 303 rc = pcim_enable_device(dev); 304 if (rc) 305 return rc; 306 307 rev = sl82c105_bridge_revision(dev); 308 309 if (rev == -1) 310 dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Unable to find bridge, disabling DMA.\n"); 311 else if (rev <= 5) 312 dev_printk(KERN_WARNING, &dev->dev, "pata_sl82c105: Early bridge revision, no DMA available.\n"); 313 else 314 ppi[0] = &info_dma; 315 316 pci_read_config_dword(dev, 0x40, &val); 317 val |= CTRL_P0EN | CTRL_P0F16 | CTRL_P1F16; 318 pci_write_config_dword(dev, 0x40, val); 319 320 return ata_pci_sff_init_one(dev, ppi, &sl82c105_sht, NULL); 321 } 322 323 static const struct pci_device_id sl82c105[] = { 324 { PCI_VDEVICE(WINBOND, PCI_DEVICE_ID_WINBOND_82C105), }, 325 326 { }, 327 }; 328 329 static struct pci_driver sl82c105_pci_driver = { 330 .name = DRV_NAME, 331 .id_table = sl82c105, 332 .probe = sl82c105_init_one, 333 .remove = ata_pci_remove_one 334 }; 335 336 static int __init sl82c105_init(void) 337 { 338 return pci_register_driver(&sl82c105_pci_driver); 339 } 340 341 static void __exit sl82c105_exit(void) 342 { 343 pci_unregister_driver(&sl82c105_pci_driver); 344 } 345 346 MODULE_AUTHOR("Alan Cox"); 347 MODULE_DESCRIPTION("low-level driver for Sl82c105"); 348 MODULE_LICENSE("GPL"); 349 MODULE_DEVICE_TABLE(pci, sl82c105); 350 MODULE_VERSION(DRV_VERSION); 351 352 module_init(sl82c105_init); 353 module_exit(sl82c105_exit); 354