drivers/ata/pata_cs5536.c

   1 /*
   2  * pata_cs5536.c        - CS5536 PATA for new ATA layer
   3  *                        (C) 2007 Martin K. Petersen <mkp@mkp.net>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2 as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  17  *
  18  * Documentation:
  19  *      Available from AMD web site.
  20  *
  21  * The IDE timing registers for the CS5536 live in the Geode Machine
  22  * Specific Register file and not PCI config space.  Most BIOSes
  23  * virtualize the PCI registers so the chip looks like a standard IDE
  24  * controller.  Unfortunately not all implementations get this right.
  25  * In particular some have problems with unaligned accesses to the
  26  * virtualized PCI registers.  This driver always does full dword
  27  * writes to work around the issue.  Also, in case of a bad BIOS this
  28  * driver can be loaded with the "msr=1" parameter which forces using
  29  * the Machine Specific Registers to configure the device.
  30  */
  31
  32 #include <linux/kernel.h>
  33 #include <linux/module.h>
  34 #include <linux/pci.h>
  35 #include <linux/init.h>
  36 #include <linux/blkdev.h>
  37 #include <linux/delay.h>
  38 #include <linux/libata.h>
  39 #include <scsi/scsi_host.h>
  40 #include <asm/msr.h>
  41
  42 #define DRV_NAME        "pata_cs5536"
  43 #define DRV_VERSION     "0.0.7"
  44
  45 enum {
  46         CFG                     = 0,
  47         DTC                     = 1,
  48         CAST                    = 2,
  49         ETC                     = 3,
  50
  51         MSR_IDE_BASE            = 0x51300000,
  52         MSR_IDE_CFG             = (MSR_IDE_BASE + 0x10),
  53         MSR_IDE_DTC             = (MSR_IDE_BASE + 0x12),
  54         MSR_IDE_CAST            = (MSR_IDE_BASE + 0x13),
  55         MSR_IDE_ETC             = (MSR_IDE_BASE + 0x14),
  56
  57         PCI_IDE_CFG             = 0x40,
  58         PCI_IDE_DTC             = 0x48,
  59         PCI_IDE_CAST            = 0x4c,
  60         PCI_IDE_ETC             = 0x50,
  61
  62         IDE_CFG_CHANEN          = 0x2,
  63         IDE_CFG_CABLE           = 0x10000,
  64
  65         IDE_D0_SHIFT            = 24,
  66         IDE_D1_SHIFT            = 16,
  67         IDE_DRV_MASK            = 0xff,
  68
  69         IDE_CAST_D0_SHIFT       = 6,
  70         IDE_CAST_D1_SHIFT       = 4,
  71         IDE_CAST_DRV_MASK       = 0x3,
  72         IDE_CAST_CMD_MASK       = 0xff,
  73         IDE_CAST_CMD_SHIFT      = 24,
  74
  75         IDE_ETC_NODMA           = 0x03,
  76 };
  77
  78 static int use_msr;
  79
  80 static const u32 msr_reg[4] = {
  81         MSR_IDE_CFG, MSR_IDE_DTC, MSR_IDE_CAST, MSR_IDE_ETC,
  82 };
  83
  84 static const u8 pci_reg[4] = {
  85         PCI_IDE_CFG, PCI_IDE_DTC, PCI_IDE_CAST, PCI_IDE_ETC,
  86 };
  87
  88 static inline int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
  89 {
  90         if (unlikely(use_msr)) {
  91                 u32 dummy;
  92
  93                 rdmsr(msr_reg[reg], *val, dummy);
  94                 return 0;
  95         }
  96
  97         return pci_read_config_dword(pdev, pci_reg[reg], val);
  98 }
  99
 100 static inline int cs5536_write(struct pci_dev *pdev, int reg, int val)
 101 {
 102         if (unlikely(use_msr)) {
 103                 wrmsr(msr_reg[reg], val, 0);
 104                 return 0;
 105         }
 106
 107         return pci_write_config_dword(pdev, pci_reg[reg], val);
 108 }
 109
 110 /**
 111  *      cs5536_cable_detect     -       detect cable type
 112  *      @ap: Port to detect on
 113  *
 114  *      Perform cable detection for ATA66 capable cable. Return a libata
 115  *      cable type.
 116  */
 117
 118 static int cs5536_cable_detect(struct ata_port *ap)
 119 {
 120         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 121         u32 cfg;
 122
 123         cs5536_read(pdev, CFG, &cfg);
 124
 125         if (cfg & (IDE_CFG_CABLE << ap->port_no))
 126                 return ATA_CBL_PATA80;
 127         else
 128                 return ATA_CBL_PATA40;
 129 }
 130
 131 /**
 132  *      cs5536_set_piomode              -       PIO setup
 133  *      @ap: ATA interface
 134  *      @adev: device on the interface
 135  */
 136
 137 static void cs5536_set_piomode(struct ata_port *ap, struct ata_device *adev)
 138 {
 139         static const u8 drv_timings[5] = {
 140                 0x98, 0x55, 0x32, 0x21, 0x20,
 141         };
 142
 143         static const u8 addr_timings[5] = {
 144                 0x2, 0x1, 0x0, 0x0, 0x0,
 145         };
 146
 147         static const u8 cmd_timings[5] = {
 148                 0x99, 0x92, 0x90, 0x22, 0x20,
 149         };
 150
 151         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 152         struct ata_device *pair = ata_dev_pair(adev);
 153         int mode = adev->pio_mode - XFER_PIO_0;
 154         int cmdmode = mode;
 155         int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
 156         int cshift = adev->devno ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
 157         u32 dtc, cast, etc;
 158
 159         if (pair)
 160                 cmdmode = min(mode, pair->pio_mode - XFER_PIO_0);
 161
 162         cs5536_read(pdev, DTC, &dtc);
 163         cs5536_read(pdev, CAST, &cast);
 164         cs5536_read(pdev, ETC, &etc);
 165
 166         dtc &= ~(IDE_DRV_MASK << dshift);
 167         dtc |= drv_timings[mode] << dshift;
 168
 169         cast &= ~(IDE_CAST_DRV_MASK << cshift);
 170         cast |= addr_timings[mode] << cshift;
 171
 172         cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
 173         cast |= cmd_timings[cmdmode] << IDE_CAST_CMD_SHIFT;
 174
 175         etc &= ~(IDE_DRV_MASK << dshift);
 176         etc |= IDE_ETC_NODMA << dshift;
 177
 178         cs5536_write(pdev, DTC, dtc);
 179         cs5536_write(pdev, CAST, cast);
 180         cs5536_write(pdev, ETC, etc);
 181 }
 182
 183 /**
 184  *      cs5536_set_dmamode              -       DMA timing setup
 185  *      @ap: ATA interface
 186  *      @adev: Device being configured
 187  *
 188  */
 189
 190 static void cs5536_set_dmamode(struct ata_port *ap, struct ata_device *adev)
 191 {
 192         static const u8 udma_timings[6] = {
 193                 0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
 194         };
 195
 196         static const u8 mwdma_timings[3] = {
 197                 0x67, 0x21, 0x20,
 198         };
 199
 200         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 201         u32 dtc, etc;
 202         int mode = adev->dma_mode;
 203         int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
 204
 205         if (mode >= XFER_UDMA_0) {
 206                 cs5536_read(pdev, ETC, &etc);
 207
 208                 etc &= ~(IDE_DRV_MASK << dshift);
 209                 etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
 210
 211                 cs5536_write(pdev, ETC, etc);
 212         } else { /* MWDMA */
 213                 cs5536_read(pdev, DTC, &dtc);
 214
 215                 dtc &= ~(IDE_DRV_MASK << dshift);
 216                 dtc |= mwdma_timings[mode - XFER_MW_DMA_0] << dshift;
 217
 218                 cs5536_write(pdev, DTC, dtc);
 219         }
 220 }
 221
 222 static struct scsi_host_template cs5536_sht = {
 223         ATA_BMDMA_SHT(DRV_NAME),
 224 };
 225
 226 static struct ata_port_operations cs5536_port_ops = {
 227         .inherits               = &ata_bmdma32_port_ops,
 228         .cable_detect           = cs5536_cable_detect,
 229         .set_piomode            = cs5536_set_piomode,
 230         .set_dmamode            = cs5536_set_dmamode,
 231 };
 232
 233 /**
 234  *      cs5536_init_one
 235  *      @dev: PCI device
 236  *      @id: Entry in match table
 237  *
 238  */
 239
 240 static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 241 {
 242         static const struct ata_port_info info = {
 243                 .flags = ATA_FLAG_SLAVE_POSS,
 244                 .pio_mask = ATA_PIO4,
 245                 .mwdma_mask = ATA_MWDMA2,
 246                 .udma_mask = ATA_UDMA5,
 247                 .port_ops = &cs5536_port_ops,
 248         };
 249
 250         const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info };
 251         u32 cfg;
 252
 253         if (use_msr)
 254                 printk(KERN_ERR DRV_NAME ": Using MSR regs instead of PCI\n");
 255
 256         cs5536_read(dev, CFG, &cfg);
 257
 258         if ((cfg & IDE_CFG_CHANEN) == 0) {
 259                 printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
 260                 return -ENODEV;
 261         }
 262
 263         return ata_pci_sff_init_one(dev, ppi, &cs5536_sht, NULL, 0);
 264 }
 265
 266 static const struct pci_device_id cs5536[] = {
 267         { PCI_VDEVICE(AMD,      PCI_DEVICE_ID_AMD_CS5536_IDE), },
 268         { },
 269 };
 270
 271 static struct pci_driver cs5536_pci_driver = {
 272         .name           = DRV_NAME,
 273         .id_table       = cs5536,
 274         .probe          = cs5536_init_one,
 275         .remove         = ata_pci_remove_one,
 276 #ifdef CONFIG_PM
 277         .suspend        = ata_pci_device_suspend,
 278         .resume         = ata_pci_device_resume,
 279 #endif
 280 };
 281
 282 static int __init cs5536_init(void)
 283 {
 284         return pci_register_driver(&cs5536_pci_driver);
 285 }
 286
 287 static void __exit cs5536_exit(void)
 288 {
 289         pci_unregister_driver(&cs5536_pci_driver);
 290 }
 291
 292 MODULE_AUTHOR("Martin K. Petersen");
 293 MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
 294 MODULE_LICENSE("GPL");
 295 MODULE_DEVICE_TABLE(pci, cs5536);
 296 MODULE_VERSION(DRV_VERSION);
 297 module_param_named(msr, use_msr, int, 0644);
 298 MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
 299
 300 module_init(cs5536_init);
 301 module_exit(cs5536_exit);