drivers/ide/ide-xfer-mode.c

   1 #include <linux/types.h>
   2 #include <linux/string.h>
   3 #include <linux/kernel.h>
   4 #include <linux/export.h>
   5 #include <linux/interrupt.h>
   6 #include <linux/ide.h>
   7 #include <linux/bitops.h>
   8
   9 static const char *udma_str[] =
  10          { "UDMA/16", "UDMA/25",  "UDMA/33",  "UDMA/44",
  11            "UDMA/66", "UDMA/100", "UDMA/133", "UDMA7" };
  12 static const char *mwdma_str[] =
  13         { "MWDMA0", "MWDMA1", "MWDMA2", "MWDMA3", "MWDMA4" };
  14 static const char *swdma_str[] =
  15         { "SWDMA0", "SWDMA1", "SWDMA2" };
  16 static const char *pio_str[] =
  17         { "PIO0", "PIO1", "PIO2", "PIO3", "PIO4", "PIO5", "PIO6" };
  18
  19 /**
  20  *      ide_xfer_verbose        -       return IDE mode names
  21  *      @mode: transfer mode
  22  *
  23  *      Returns a constant string giving the name of the mode
  24  *      requested.
  25  */
  26
  27 const char *ide_xfer_verbose(u8 mode)
  28 {
  29         const char *s;
  30         u8 i = mode & 0xf;
  31
  32         if (mode >= XFER_UDMA_0 && mode <= XFER_UDMA_7)
  33                 s = udma_str[i];
  34         else if (mode >= XFER_MW_DMA_0 && mode <= XFER_MW_DMA_4)
  35                 s = mwdma_str[i];
  36         else if (mode >= XFER_SW_DMA_0 && mode <= XFER_SW_DMA_2)
  37                 s = swdma_str[i];
  38         else if (mode >= XFER_PIO_0 && mode <= XFER_PIO_6)
  39                 s = pio_str[i & 0x7];
  40         else if (mode == XFER_PIO_SLOW)
  41                 s = "PIO SLOW";
  42         else
  43                 s = "XFER ERROR";
  44
  45         return s;
  46 }
  47 EXPORT_SYMBOL(ide_xfer_verbose);
  48
  49 /**
  50  *      ide_get_best_pio_mode   -       get PIO mode from drive
  51  *      @drive: drive to consider
  52  *      @mode_wanted: preferred mode
  53  *      @max_mode: highest allowed mode
  54  *
  55  *      This routine returns the recommended PIO settings for a given drive,
  56  *      based on the drive->id information and the ide_pio_blacklist[].
  57  *
  58  *      Drive PIO mode is auto-selected if 255 is passed as mode_wanted.
  59  *      This is used by most chipset support modules when "auto-tuning".
  60  */
  61
  62 static u8 ide_get_best_pio_mode(ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
  63 {
  64         u16 *id = drive->id;
  65         int pio_mode = -1, overridden = 0;
  66
  67         if (mode_wanted != 255)
  68                 return min_t(u8, mode_wanted, max_mode);
  69
  70         if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0)
  71                 pio_mode = ide_scan_pio_blacklist((char *)&id[ATA_ID_PROD]);
  72
  73         if (pio_mode != -1) {
  74                 printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
  75         } else {
  76                 pio_mode = id[ATA_ID_OLD_PIO_MODES] >> 8;
  77                 if (pio_mode > 2) {     /* 2 is maximum allowed tPIO value */
  78                         pio_mode = 2;
  79                         overridden = 1;
  80                 }
  81
  82                 if (id[ATA_ID_FIELD_VALID] & 2) {             /* ATA2? */
  83                         if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 7))
  84                                 pio_mode = 4 + min_t(int, 2,
  85                                                      id[ATA_ID_CFA_MODES] & 7);
  86                         else if (ata_id_has_iordy(id)) {
  87                                 if (id[ATA_ID_PIO_MODES] & 7) {
  88                                         overridden = 0;
  89                                         if (id[ATA_ID_PIO_MODES] & 4)
  90                                                 pio_mode = 5;
  91                                         else if (id[ATA_ID_PIO_MODES] & 2)
  92                                                 pio_mode = 4;
  93                                         else
  94                                                 pio_mode = 3;
  95                                 }
  96                         }
  97                 }
  98
  99                 if (overridden)
 100                         printk(KERN_INFO "%s: tPIO > 2, assuming tPIO = 2\n",
 101                                          drive->name);
 102         }
 103
 104         if (pio_mode > max_mode)
 105                 pio_mode = max_mode;
 106
 107         return pio_mode;
 108 }
 109
 110 int ide_pio_need_iordy(ide_drive_t *drive, const u8 pio)
 111 {
 112         /*
 113          * IORDY may lead to controller lock up on certain controllers
 114          * if the port is not occupied.
 115          */
 116         if (pio == 0 && (drive->hwif->port_flags & IDE_PFLAG_PROBING))
 117                 return 0;
 118         return ata_id_pio_need_iordy(drive->id, pio);
 119 }
 120 EXPORT_SYMBOL_GPL(ide_pio_need_iordy);
 121
 122 int ide_set_pio_mode(ide_drive_t *drive, const u8 mode)
 123 {
 124         ide_hwif_t *hwif = drive->hwif;
 125         const struct ide_port_ops *port_ops = hwif->port_ops;
 126
 127         if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
 128                 return 0;
 129
 130         if (port_ops == NULL || port_ops->set_pio_mode == NULL)
 131                 return -1;
 132
 133         /*
 134          * TODO: temporary hack for some legacy host drivers that didn't
 135          * set transfer mode on the device in ->set_pio_mode method...
 136          */
 137         if (port_ops->set_dma_mode == NULL) {
 138                 drive->pio_mode = mode;
 139                 port_ops->set_pio_mode(hwif, drive);
 140                 return 0;
 141         }
 142
 143         if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
 144                 if (ide_config_drive_speed(drive, mode))
 145                         return -1;
 146                 drive->pio_mode = mode;
 147                 port_ops->set_pio_mode(hwif, drive);
 148                 return 0;
 149         } else {
 150                 drive->pio_mode = mode;
 151                 port_ops->set_pio_mode(hwif, drive);
 152                 return ide_config_drive_speed(drive, mode);
 153         }
 154 }
 155
 156 int ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
 157 {
 158         ide_hwif_t *hwif = drive->hwif;
 159         const struct ide_port_ops *port_ops = hwif->port_ops;
 160
 161         if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
 162                 return 0;
 163
 164         if (port_ops == NULL || port_ops->set_dma_mode == NULL)
 165                 return -1;
 166
 167         if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
 168                 if (ide_config_drive_speed(drive, mode))
 169                         return -1;
 170                 drive->dma_mode = mode;
 171                 port_ops->set_dma_mode(hwif, drive);
 172                 return 0;
 173         } else {
 174                 drive->dma_mode = mode;
 175                 port_ops->set_dma_mode(hwif, drive);
 176                 return ide_config_drive_speed(drive, mode);
 177         }
 178 }
 179 EXPORT_SYMBOL_GPL(ide_set_dma_mode);
 180
 181 /* req_pio == "255" for auto-tune */
 182 void ide_set_pio(ide_drive_t *drive, u8 req_pio)
 183 {
 184         ide_hwif_t *hwif = drive->hwif;
 185         const struct ide_port_ops *port_ops = hwif->port_ops;
 186         u8 host_pio, pio;
 187
 188         if (port_ops == NULL || port_ops->set_pio_mode == NULL ||
 189             (hwif->host_flags & IDE_HFLAG_NO_SET_MODE))
 190                 return;
 191
 192         BUG_ON(hwif->pio_mask == 0x00);
 193
 194         host_pio = fls(hwif->pio_mask) - 1;
 195
 196         pio = ide_get_best_pio_mode(drive, req_pio, host_pio);
 197
 198         /*
 199          * TODO:
 200          * - report device max PIO mode
 201          * - check req_pio != 255 against device max PIO mode
 202          */
 203         printk(KERN_DEBUG "%s: host max PIO%d wanted PIO%d%s selected PIO%d\n",
 204                           drive->name, host_pio, req_pio,
 205                           req_pio == 255 ? "(auto-tune)" : "", pio);
 206
 207         (void)ide_set_pio_mode(drive, XFER_PIO_0 + pio);
 208 }
 209 EXPORT_SYMBOL_GPL(ide_set_pio);
 210
 211 /**
 212  *      ide_rate_filter         -       filter transfer mode
 213  *      @drive: IDE device
 214  *      @speed: desired speed
 215  *
 216  *      Given the available transfer modes this function returns
 217  *      the best available speed at or below the speed requested.
 218  *
 219  *      TODO: check device PIO capabilities
 220  */
 221
 222 static u8 ide_rate_filter(ide_drive_t *drive, u8 speed)
 223 {
 224         ide_hwif_t *hwif = drive->hwif;
 225         u8 mode = ide_find_dma_mode(drive, speed);
 226
 227         if (mode == 0) {
 228                 if (hwif->pio_mask)
 229                         mode = fls(hwif->pio_mask) - 1 + XFER_PIO_0;
 230                 else
 231                         mode = XFER_PIO_4;
 232         }
 233
 234 /*      printk("%s: mode 0x%02x, speed 0x%02x\n", __func__, mode, speed); */
 235
 236         return min(speed, mode);
 237 }
 238
 239 /**
 240  *      ide_set_xfer_rate       -       set transfer rate
 241  *      @drive: drive to set
 242  *      @rate: speed to attempt to set
 243  *
 244  *      General helper for setting the speed of an IDE device. This
 245  *      function knows about user enforced limits from the configuration
 246  *      which ->set_pio_mode/->set_dma_mode does not.
 247  */
 248
 249 int ide_set_xfer_rate(ide_drive_t *drive, u8 rate)
 250 {
 251         ide_hwif_t *hwif = drive->hwif;
 252         const struct ide_port_ops *port_ops = hwif->port_ops;
 253
 254         if (port_ops == NULL || port_ops->set_dma_mode == NULL ||
 255             (hwif->host_flags & IDE_HFLAG_NO_SET_MODE))
 256                 return -1;
 257
 258         rate = ide_rate_filter(drive, rate);
 259
 260         BUG_ON(rate < XFER_PIO_0);
 261
 262         if (rate >= XFER_PIO_0 && rate <= XFER_PIO_6)
 263                 return ide_set_pio_mode(drive, rate);
 264
 265         return ide_set_dma_mode(drive, rate);
 266 }