root/drivers/ide/cs5536.c

DEFINITIONS

1. cs5536_read
2. cs5536_write
3. cs5536_program_dtc
4. cs5536_cable_detect
5. cs5536_set_pio_mode
6. cs5536_set_dma_mode
7. cs5536_dma_start
8. cs5536_dma_end
9. cs5536_init_one

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * CS5536 PATA support
   4  * (C) 2007 Martin K. Petersen <mkp@mkp.net>
   5  * (C) 2009 Bartlomiej Zolnierkiewicz
   6  *
   7  * Documentation:
   8  *      Available from AMD web site.
   9  *
  10  * The IDE timing registers for the CS5536 live in the Geode Machine
  11  * Specific Register file and not PCI config space.  Most BIOSes
  12  * virtualize the PCI registers so the chip looks like a standard IDE
  13  * controller.  Unfortunately not all implementations get this right.
  14  * In particular some have problems with unaligned accesses to the
  15  * virtualized PCI registers.  This driver always does full dword
  16  * writes to work around the issue.  Also, in case of a bad BIOS this
  17  * driver can be loaded with the "msr=1" parameter which forces using
  18  * the Machine Specific Registers to configure the device.
  19  */
  20 
  21 #include <linux/kernel.h>
  22 #include <linux/module.h>
  23 #include <linux/pci.h>
  24 #include <linux/init.h>
  25 #include <linux/ide.h>
  26 #include <asm/msr.h>
  27 
  28 #define DRV_NAME        "cs5536"
  29 
  30 enum {
  31         MSR_IDE_CFG             = 0x51300010,
  32         PCI_IDE_CFG             = 0x40,
  33 
  34         CFG                     = 0,
  35         DTC                     = 2,
  36         CAST                    = 3,
  37         ETC                     = 4,
  38 
  39         IDE_CFG_CHANEN          = (1 << 1),
  40         IDE_CFG_CABLE           = (1 << 17) | (1 << 16),
  41 
  42         IDE_D0_SHIFT            = 24,
  43         IDE_D1_SHIFT            = 16,
  44         IDE_DRV_MASK            = 0xff,
  45 
  46         IDE_CAST_D0_SHIFT       = 6,
  47         IDE_CAST_D1_SHIFT       = 4,
  48         IDE_CAST_DRV_MASK       = 0x3,
  49 
  50         IDE_CAST_CMD_SHIFT      = 24,
  51         IDE_CAST_CMD_MASK       = 0xff,
  52 
  53         IDE_ETC_UDMA_MASK       = 0xc0,
  54 };
  55 
  56 static int use_msr;
  57 
  58 static int cs5536_read(struct pci_dev *pdev, int reg, u32 *val)
  59 {
  60         if (unlikely(use_msr)) {
  61                 u32 dummy;
  62 
  63                 rdmsr(MSR_IDE_CFG + reg, *val, dummy);
  64                 return 0;
  65         }
  66 
  67         return pci_read_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
  68 }
  69 
  70 static int cs5536_write(struct pci_dev *pdev, int reg, int val)
  71 {
  72         if (unlikely(use_msr)) {
  73                 wrmsr(MSR_IDE_CFG + reg, val, 0);
  74                 return 0;
  75         }
  76 
  77         return pci_write_config_dword(pdev, PCI_IDE_CFG + reg * 4, val);
  78 }
  79 
  80 static void cs5536_program_dtc(ide_drive_t *drive, u8 tim)
  81 {
  82         struct pci_dev *pdev = to_pci_dev(drive->hwif->dev);
  83         int dshift = (drive->dn & 1) ? IDE_D1_SHIFT : IDE_D0_SHIFT;
  84         u32 dtc;
  85 
  86         cs5536_read(pdev, DTC, &dtc);
  87         dtc &= ~(IDE_DRV_MASK << dshift);
  88         dtc |= tim << dshift;
  89         cs5536_write(pdev, DTC, dtc);
  90 }
  91 
  92 /**
  93  *      cs5536_cable_detect     -       detect cable type
  94  *      @hwif: Port to detect on
  95  *
  96  *      Perform cable detection for ATA66 capable cable.
  97  *
  98  *      Returns a cable type.
  99  */
 100 
 101 static u8 cs5536_cable_detect(ide_hwif_t *hwif)
 102 {
 103         struct pci_dev *pdev = to_pci_dev(hwif->dev);
 104         u32 cfg;
 105 
 106         cs5536_read(pdev, CFG, &cfg);
 107 
 108         if (cfg & IDE_CFG_CABLE)
 109                 return ATA_CBL_PATA80;
 110         else
 111                 return ATA_CBL_PATA40;
 112 }
 113 
 114 /**
 115  *      cs5536_set_pio_mode             -       PIO timing setup
 116  *      @hwif: ATA port
 117  *      @drive: ATA device
 118  */
 119 
 120 static void cs5536_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
 121 {
 122         static const u8 drv_timings[5] = {
 123                 0x98, 0x55, 0x32, 0x21, 0x20,
 124         };
 125 
 126         static const u8 addr_timings[5] = {
 127                 0x2, 0x1, 0x0, 0x0, 0x0,
 128         };
 129 
 130         static const u8 cmd_timings[5] = {
 131                 0x99, 0x92, 0x90, 0x22, 0x20,
 132         };
 133 
 134         struct pci_dev *pdev = to_pci_dev(hwif->dev);
 135         ide_drive_t *pair = ide_get_pair_dev(drive);
 136         int cshift = (drive->dn & 1) ? IDE_CAST_D1_SHIFT : IDE_CAST_D0_SHIFT;
 137         unsigned long timings = (unsigned long)ide_get_drivedata(drive);
 138         u32 cast;
 139         const u8 pio = drive->pio_mode - XFER_PIO_0;
 140         u8 cmd_pio = pio;
 141 
 142         if (pair)
 143                 cmd_pio = min_t(u8, pio, pair->pio_mode - XFER_PIO_0);
 144 
 145         timings &= (IDE_DRV_MASK << 8);
 146         timings |= drv_timings[pio];
 147         ide_set_drivedata(drive, (void *)timings);
 148 
 149         cs5536_program_dtc(drive, drv_timings[pio]);
 150 
 151         cs5536_read(pdev, CAST, &cast);
 152 
 153         cast &= ~(IDE_CAST_DRV_MASK << cshift);
 154         cast |= addr_timings[pio] << cshift;
 155 
 156         cast &= ~(IDE_CAST_CMD_MASK << IDE_CAST_CMD_SHIFT);
 157         cast |= cmd_timings[cmd_pio] << IDE_CAST_CMD_SHIFT;
 158 
 159         cs5536_write(pdev, CAST, cast);
 160 }
 161 
 162 /**
 163  *      cs5536_set_dma_mode             -       DMA timing setup
 164  *      @hwif: ATA port
 165  *      @drive: ATA device
 166  */
 167 
 168 static void cs5536_set_dma_mode(ide_hwif_t *hwif, ide_drive_t *drive)
 169 {
 170         static const u8 udma_timings[6] = {
 171                 0xc2, 0xc1, 0xc0, 0xc4, 0xc5, 0xc6,
 172         };
 173 
 174         static const u8 mwdma_timings[3] = {
 175                 0x67, 0x21, 0x20,
 176         };
 177 
 178         struct pci_dev *pdev = to_pci_dev(hwif->dev);
 179         int dshift = (drive->dn & 1) ? IDE_D1_SHIFT : IDE_D0_SHIFT;
 180         unsigned long timings = (unsigned long)ide_get_drivedata(drive);
 181         u32 etc;
 182         const u8 mode = drive->dma_mode;
 183 
 184         cs5536_read(pdev, ETC, &etc);
 185 
 186         if (mode >= XFER_UDMA_0) {
 187                 etc &= ~(IDE_DRV_MASK << dshift);
 188                 etc |= udma_timings[mode - XFER_UDMA_0] << dshift;
 189         } else { /* MWDMA */
 190                 etc &= ~(IDE_ETC_UDMA_MASK << dshift);
 191                 timings &= IDE_DRV_MASK;
 192                 timings |= mwdma_timings[mode - XFER_MW_DMA_0] << 8;
 193                 ide_set_drivedata(drive, (void *)timings);
 194         }
 195 
 196         cs5536_write(pdev, ETC, etc);
 197 }
 198 
 199 static void cs5536_dma_start(ide_drive_t *drive)
 200 {
 201         unsigned long timings = (unsigned long)ide_get_drivedata(drive);
 202 
 203         if (drive->current_speed < XFER_UDMA_0 &&
 204             (timings >> 8) != (timings & IDE_DRV_MASK))
 205                 cs5536_program_dtc(drive, timings >> 8);
 206 
 207         ide_dma_start(drive);
 208 }
 209 
 210 static int cs5536_dma_end(ide_drive_t *drive)
 211 {
 212         int ret = ide_dma_end(drive);
 213         unsigned long timings = (unsigned long)ide_get_drivedata(drive);
 214 
 215         if (drive->current_speed < XFER_UDMA_0 &&
 216             (timings >> 8) != (timings & IDE_DRV_MASK))
 217                 cs5536_program_dtc(drive, timings & IDE_DRV_MASK);
 218 
 219         return ret;
 220 }
 221 
 222 static const struct ide_port_ops cs5536_port_ops = {
 223         .set_pio_mode           = cs5536_set_pio_mode,
 224         .set_dma_mode           = cs5536_set_dma_mode,
 225         .cable_detect           = cs5536_cable_detect,
 226 };
 227 
 228 static const struct ide_dma_ops cs5536_dma_ops = {
 229         .dma_host_set           = ide_dma_host_set,
 230         .dma_setup              = ide_dma_setup,
 231         .dma_start              = cs5536_dma_start,
 232         .dma_end                = cs5536_dma_end,
 233         .dma_test_irq           = ide_dma_test_irq,
 234         .dma_lost_irq           = ide_dma_lost_irq,
 235         .dma_timer_expiry       = ide_dma_sff_timer_expiry,
 236         .dma_sff_read_status    = ide_dma_sff_read_status,
 237 };
 238 
 239 static const struct ide_port_info cs5536_info = {
 240         .name           = DRV_NAME,
 241         .port_ops       = &cs5536_port_ops,
 242         .dma_ops        = &cs5536_dma_ops,
 243         .host_flags     = IDE_HFLAG_SINGLE,
 244         .pio_mask       = ATA_PIO4,
 245         .mwdma_mask     = ATA_MWDMA2,
 246         .udma_mask      = ATA_UDMA5,
 247 };
 248 
 249 /**
 250  *      cs5536_init_one
 251  *      @dev: PCI device
 252  *      @id: Entry in match table
 253  */
 254 
 255 static int cs5536_init_one(struct pci_dev *dev, const struct pci_device_id *id)
 256 {
 257         u32 cfg;
 258 
 259         if (use_msr)
 260                 printk(KERN_INFO DRV_NAME ": Using MSR regs instead of PCI\n");
 261 
 262         cs5536_read(dev, CFG, &cfg);
 263 
 264         if ((cfg & IDE_CFG_CHANEN) == 0) {
 265                 printk(KERN_ERR DRV_NAME ": disabled by BIOS\n");
 266                 return -ENODEV;
 267         }
 268 
 269         return ide_pci_init_one(dev, &cs5536_info, NULL);
 270 }
 271 
 272 static const struct pci_device_id cs5536_pci_tbl[] = {
 273         { PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_CS5536_IDE), },
 274         { },
 275 };
 276 
 277 static struct pci_driver cs5536_pci_driver = {
 278         .name           = DRV_NAME,
 279         .id_table       = cs5536_pci_tbl,
 280         .probe          = cs5536_init_one,
 281         .remove         = ide_pci_remove,
 282         .suspend        = ide_pci_suspend,
 283         .resume         = ide_pci_resume,
 284 };
 285 
 286 module_pci_driver(cs5536_pci_driver);
 287 
 288 MODULE_AUTHOR("Martin K. Petersen, Bartlomiej Zolnierkiewicz");
 289 MODULE_DESCRIPTION("low-level driver for the CS5536 IDE controller");
 290 MODULE_LICENSE("GPL");
 291 MODULE_DEVICE_TABLE(pci, cs5536_pci_tbl);
 292 
 293 module_param_named(msr, use_msr, int, 0644);
 294 MODULE_PARM_DESC(msr, "Force using MSR to configure IDE function (Default: 0)");