release/src-rt-6.x.4708/linux/linux-2.6.36/drivers/ide/ide-xfer-mode.c

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