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  *                        (C) 2011 Bartlomiej Zolnierkiewicz
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  *
  19  * Documentation:
  20  *      Available from AMD web site.
  21  *
  22  * The IDE timing registers for the CS5536 live in the Geode Machine
  23  * Specific Register file and not PCI config space.  Most BIOSes
  24  * virtualize the PCI registers so the chip looks like a standard IDE
  25  * controller.  Unfortunately not all implementations get this right.
  26  * In particular some have problems with unaligned accesses to the
  27  * virtualized PCI registers.  This driver always does full dword
  28  * writes to work around the issue.  Also, in case of a bad BIOS this
  29  * driver can be loaded with the "msr=1" parameter which forces using
  30  * the Machine Specific Registers to configure the device.
  31  */
  32
  33 #include <linux/kernel.h>
  34 #include <linux/module.h>
  35 #include <linux/pci.h>
  36 #include <linux/init.h>
  37 #include <linux/blkdev.h>
  38 #include <linux/delay.h>
  39 #include <linux/libata.h>
  40 #include <scsi/scsi_host.h>
  41
  42 #ifdef CONFIG_X86_32
  43 #include <asm/msr.h>
  44 static int use_msr;
  45 module_param_named(msr, use_msr, int, 0644);
  46 MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");
  47 #else
  48 #undef rdmsr    /* avoid accidental MSR usage on, e.g. x86-64 */
  49 #undef wrmsr
  50 #define rdmsr(x, y, z) do { } while (0)
  51 #define wrmsr(x, y, z) do { } while (0)
  52 #define use_msr 0
  53 #endif
  54
  55 #define DRV_NAME        "pata_cs5536"
  56 #define DRV_VERSION     "0.0.8"
  57
  58 enum {
  59         MSR_IDE_CFG             = 0x51300010,
  60         PCI_IDE_CFG             = 0x40,
  61
  62         CFG                     = 0,
  63         DTC                     = 2,
  64         CAST                    = 3,
  65         ETC                     = 4,
  66
  67         IDE_CFG_CHANEN          = (1 << 1),
  68         IDE_CFG_CABLE           = (1 << 17) | (1 << 16),
  69
  70         IDE_D0_SHIFT            = 24,
  71         IDE_D1_SHIFT            = 16,
  72         IDE_DRV_MASK            = 0xff,
  73
  74         IDE_CAST_D0_SHIFT       = 6,
  75         IDE_CAST_D1_SHIFT       = 4,
  76         IDE_CAST_DRV_MASK       = 0x3,
  77         IDE_CAST_CMD_MASK       = 0xff,
  78         IDE_CAST_CMD_SHIFT      = 24,
  79
  80         IDE_ETC_UDMA_MASK       = 0xc0,
  81 };
  82
  83 static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
  84 {
  85         if (unlikely(use_msr)) {
  86                 u32 dummy __maybe_unused;
  87
  88                 rdmsr(MSR_IDE_CFG + reg, *val, dummy);
  89                 return 0;
  90         }
  91
  92         return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
  93 }
  94
  95 static int cs5536_write(struct pci_dev *pdev, int reg, int val)
  96 {
  97         if (unlikely(use_msr)) {
  98                 wrmsr(MSR_IDE_CFG + reg, val, 0);
  99                 return 0;
 100         }
 101
 102         return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
 103 }
 104
 105 static void cs5536_program_dtc(struct ata_device *adev, u8 tim)
 106 {
 107         struct pci_dev *pdev = to_pci_dev(adev->link->ap->host->dev);
 108         int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
 109         u32 dtc;
 110
 111         cs5536_read(pdev, DTC, &dtc);
 112         dtc &= ~(IDE_DRV_MASK << dshift);
 113         dtc |= tim << dshift;
 114         cs5536_write(pdev, DTC, dtc);
 115 }
 116
 117 /**
 118  *      cs5536_cable_detect     -       detect cable type
 119  *      @ap: Port to detect on
 120  *
 121  *      Perform cable detection for ATA66 capable cable.
 122  *
 123  *      Returns a cable type.
 124  */
 125
 126 static int cs5536_cable_detect(struct ata_port *ap)
 127 {
 128         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 129         u32 cfg;
 130
 131         cs5536_read(pdev, CFG, &cfg);
 132
 133         if (cfg & IDE_CFG_CABLE)
 134                 return ATA_CBL_PATA80;
 135         else
 136                 return ATA_CBL_PATA40;
 137 }
 138
 139 /**
 140  *      cs5536_set_piomode              -       PIO setup
 141  *      @ap: ATA interface
 142  *      @adev: device on the interface
 143  */
 144
 145 static void cs5536_set_piomode(struct ata_port *ap, struct ata_device *adev)
 146 {
 147         static const u8 drv_timings[5] = {
 148                 0x98, 0x55, 0x32, 0x21, 0x20,
 149         };
 150
 151         static const u8 addr_timings[5] = {
 152                 0x2, 0x1, 0x0, 0x0, 0x0,
 153         };
 154
 155         static const u8 cmd_timings[5] = {
 156                 0x99, 0x92, 0x90, 0x22, 0x20,
 157         };
 158
 159         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 160         struct ata_device *pair = ata_dev_pair(adev);
 161         int mode = adev->pio_mode - XFER_PIO_0;
 162         int cmdmode = mode;
 163         int cshift = adev->devno ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
 164         u32 cast;
 165
 166         if (pair)
 167                 cmdmode = min(mode, pair->pio_mode - XFER_PIO_0);
 168
 169         cs5536_program_dtc(adev, drv_timings[mode]);
 170
 171         cs5536_read(pdev, CAST, &cast);
 172
 173         cast &= ~(IDE_CAST_DRV_MASK << cshift);
 174         cast |= addr_timings[mode] << cshift;
 175
 176         cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
 177         cast |= cmd_timings[cmdmode] << IDE_CAST_CMD_SHIFT;
 178
 179         cs5536_write(pdev, CAST, cast);
 180 }
 181
 182 /**
 183  *      cs5536_set_dmamode              -       DMA timing setup
 184  *      @ap: ATA interface
 185  *      @adev: Device being configured
 186  *
 187  */
 188
 189 static void cs5536_set_dmamode(struct ata_port *ap, struct ata_device *adev)
 190 {
 191         static const u8 udma_timings[6] = {
 192                 0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
 193         };
 194
 195         static const u8 mwdma_timings[3] = {
 196                 0x67, 0x21, 0x20,
 197         };
 198
 199         struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 200         u32 etc;
 201         int mode = adev->dma_mode;
 202         int dshift = adev->devno ? IDE_D1_SHIFT : IDE_D0_SHIFT;
 203
 204         cs5536_read(pdev, ETC, &etc);
 205
 206         if (mode >= XFER_UDMA_0) {
 207                 etc &= ~(IDE_DRV_MASK << dshift);
 208                 etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
 209         } else { /* MWDMA */
 210                 etc &= ~(IDE_ETC_UDMA_MASK << dshift);
 211                 cs5536_program_dtc(adev, mwdma_timings[mode - XFER_MW_DMA_0]);
 212         }
 213
 214         cs5536_write(pdev, ETC, etc);
 215 }
 216
 217 static struct scsi_host_template cs5536_sht = {
 218         ATA_BMDMA_SHT(DRV_NAME),
 219 };
 220
 221 static struct ata_port_operations cs5536_port_ops = {
 222         .inherits               = &ata_bmdma32_port_ops,
 223         .cable_detect           = cs5536_cable_detect,
 224         .set_piomode            = cs5536_set_piomode,
 225         .set_dmamode            = cs5536_set_dmamode,
 226 };
 227
 228 /**
 229  *      cs5536_init_one
 230  *      @dev: PCI device
 231  *      @id: Entry in match table
 232  *
 233  */
 234
 235 static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 236 {
 237         static const struct ata_port_info info = {
 238                 .flags = ATA_FLAG_SLAVE_POSS,
 239                 .pio_mask = ATA_PIO4,
 240                 .mwdma_mask = ATA_MWDMA2,
 241                 .udma_mask = ATA_UDMA5,
 242                 .port_ops = &cs5536_port_ops,
 243         };
 244
 245         const struct ata_port_info *ppi[] = { &info, &ata_dummy_port_info };
 246         u32 cfg;
 247
 248         if (use_msr)
 249                 printk(KERN_ERR DRV_NAME ": Using MSR regs instead of PCI\n");
 250
 251         cs5536_read(dev, CFG, &cfg);
 252
 253         if ((cfg & IDE_CFG_CHANEN) == 0) {
 254                 printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
 255                 return -ENODEV;
 256         }
 257
 258         return ata_pci_bmdma_init_one(dev, ppi, &cs5536_sht, NULL, 0);
 259 }
 260
 261 static const struct pci_device_id cs5536[] = {
 262         { PCI_VDEVICE(AMD,      PCI_DEVICE_ID_AMD_CS5536_IDE), },
 263         { },
 264 };
 265
 266 static struct pci_driver cs5536_pci_driver = {
 267         .name           = DRV_NAME,
 268         .id_table       = cs5536,
 269         .probe          = cs5536_init_one,
 270         .remove         = ata_pci_remove_one,
 271 #ifdef CONFIG_PM
 272         .suspend        = ata_pci_device_suspend,
 273         .resume         = ata_pci_device_resume,
 274 #endif
 275 };
 276
 277 static int __init cs5536_init(void)
 278 {
 279         return pci_register_driver(&cs5536_pci_driver);
 280 }
 281
 282 static void __exit cs5536_exit(void)
 283 {
 284         pci_unregister_driver(&cs5536_pci_driver);
 285 }
 286
 287 MODULE_AUTHOR("Martin K. Petersen");
 288 MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
 289 MODULE_LICENSE("GPL");
 290 MODULE_DEVICE_TABLE(pci, cs5536);
 291 MODULE_VERSION(DRV_VERSION);
 292
 293 module_init(cs5536_init);
 294 module_exit(cs5536_exit);