disk/ata_pthru.c

   1 /* ata_pthru.c - ATA pass through for ata.mod.  */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2009  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/ata.h>
  21 #include <grub/disk.h>
  22 #include <grub/dl.h>
  23 #include <grub/mm.h>
  24
  25
  26 /* ATA pass through support, used by hdparm.mod.  */
  27 static grub_err_t
  28 grub_ata_pass_through (grub_disk_t disk,
  29                        struct grub_disk_ata_pass_through_parms *parms)
  30 {
  31   if (disk->dev->id != GRUB_DISK_DEVICE_ATA_ID)
  32     return grub_error (GRUB_ERR_BAD_DEVICE,
  33                        "Device not accessed via ata.mod");
  34
  35   struct grub_ata_device *dev = (struct grub_ata_device *) disk->data;
  36
  37   if (! (parms->size == 0 || parms->size == GRUB_DISK_SECTOR_SIZE))
  38     return grub_error (GRUB_ERR_NOT_IMPLEMENTED_YET,
  39                        "ATA multi-sector read and DATA OUT not implemented");
  40
  41   grub_dprintf ("ata", "ata_pass_through: cmd=0x%x, features=0x%x, sectors=0x%x\n",
  42                 parms->taskfile[GRUB_ATA_REG_CMD],
  43                 parms->taskfile[GRUB_ATA_REG_FEATURES],
  44                 parms->taskfile[GRUB_ATA_REG_SECTORS]);
  45   grub_dprintf ("ata", "lba_high=0x%x, lba_mid=0x%x, lba_low=0x%x, size=%d\n",
  46                 parms->taskfile[GRUB_ATA_REG_LBAHIGH],
  47                 parms->taskfile[GRUB_ATA_REG_LBAMID],
  48                 parms->taskfile[GRUB_ATA_REG_LBALOW], parms->size);
  49
  50   /* Set registers.  */
  51   grub_ata_regset (dev, GRUB_ATA_REG_DISK, 0xE0 | dev->device << 4
  52                    | (parms->taskfile[GRUB_ATA_REG_DISK] & 0xf));
  53   if (grub_ata_check_ready (dev))
  54     return grub_errno;
  55
  56   int i;
  57   for (i = GRUB_ATA_REG_FEATURES; i <= GRUB_ATA_REG_LBAHIGH; i++)
  58     grub_ata_regset (dev, i, parms->taskfile[i]);
  59
  60   /* Start command. */
  61   grub_ata_regset (dev, GRUB_ATA_REG_CMD, parms->taskfile[GRUB_ATA_REG_CMD]);
  62
  63   /* Wait for !BSY.  */
  64   if (grub_ata_wait_not_busy (dev, GRUB_ATA_TOUT_DATA))
  65     return grub_errno;
  66
  67   /* Check status.  */
  68   grub_int8_t sts = grub_ata_regget (dev, GRUB_ATA_REG_STATUS);
  69   grub_dprintf ("ata", "status=0x%x\n", sts);
  70
  71   /* Transfer data.  */
  72   if ((sts & (GRUB_ATA_STATUS_DRQ | GRUB_ATA_STATUS_ERR)) == GRUB_ATA_STATUS_DRQ)
  73     {
  74       if (parms->size != GRUB_DISK_SECTOR_SIZE)
  75         return grub_error (GRUB_ERR_READ_ERROR, "DRQ unexpected");
  76       grub_ata_pio_read (dev, parms->buffer, GRUB_DISK_SECTOR_SIZE);
  77     }
  78
  79   /* Return registers.  */
  80   for (i = GRUB_ATA_REG_ERROR; i <= GRUB_ATA_REG_STATUS; i++)
  81     parms->taskfile[i] = grub_ata_regget (dev, i);
  82
  83   grub_dprintf ("ata", "status=0x%x, error=0x%x, sectors=0x%x\n",
  84                 parms->taskfile[GRUB_ATA_REG_STATUS],
  85                 parms->taskfile[GRUB_ATA_REG_ERROR],
  86                 parms->taskfile[GRUB_ATA_REG_SECTORS]);
  87
  88   if (parms->taskfile[GRUB_ATA_REG_STATUS]
  89       & (GRUB_ATA_STATUS_DRQ | GRUB_ATA_STATUS_ERR))
  90     return grub_error (GRUB_ERR_READ_ERROR, "ATA passthrough failed");
  91
  92   return GRUB_ERR_NONE;
  93 }
  94
  95 \f
  96
  97 GRUB_MOD_INIT(ata_pthru)
  98 {
  99   (void) mod;
 100
 101   /* Register ATA pass through function.  */
 102   grub_disk_ata_pass_through = grub_ata_pass_through;
 103 }
 104
 105 GRUB_MOD_FINI(ata_pthru)
 106 {
 107   if (grub_disk_ata_pass_through == grub_ata_pass_through)
 108     grub_disk_ata_pass_through = NULL;
 109 }