📄 disk.c
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//==========================================================================
//
// io/disk/disk.c
//
// High level disk driver
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 2003 Savin Zlobec
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s): savin
// Date: 2003-06-10
// Purpose: Top level disk driver
// Description:
//
//####DESCRIPTIONEND####
//
//==========================================================================
#include <pkgconf/io.h>
#include <pkgconf/io_disk.h>
#include <cyg/io/io.h>
#include <cyg/io/devtab.h>
#include <cyg/io/disk.h>
#include <cyg/infra/cyg_ass.h> // assertion support
#include <cyg/infra/diag.h> // diagnostic output
#include <stdlib.h> // malloc
// ---------------------------------------------------------------------------
//#define DEBUG 1
#ifdef DEBUG
# define D(_args_) diag_printf _args_
#else
# define D(_args_)
#endif
// ---------------------------------------------------------------------------
// Master Boot Record defines
#define MBR_SIG_ADDR 0x1FE // signature address
#define MBR_SIG_BYTE0 0x55 // signature first byte value
#define MBR_SIG_BYTE1 0xAA // signature second byte value
#define MBR_PART_ADDR 0x1BE // first partition address
#define MBR_PART_SIZE 0x10 // partition size
#define MBR_PART_NUM 4 // number of partitions
// Get cylinders, heads and sectors from data (MBR partition format)
#define READ_CHS(_data_, _c_, _h_, _s_) \ do { \ _h_ = (*((cyg_uint8 *)_data_)); \ _s_ = (*(((cyg_uint8 *)_data_)+1) & 0x3F); \ _c_ = (*(((cyg_uint8 *)_data_)+1) & ~0x3F) << 2 | \ (*(((cyg_uint8 *)_data_)+2)); \ } while (0)
// Get double word from data (MBR partition format)
#define READ_DWORD(_data_, _val_) \ do { \ _val_ = *((cyg_uint8 *)_data_) | \ *(((cyg_uint8 *)_data_)+1) << 8 | \ *(((cyg_uint8 *)_data_)+2) << 16 | \ *(((cyg_uint8 *)_data_)+3) << 24; \ } while (0)
// Convert cylinders, heads and sectors to LBA sectors
#define CHS_TO_LBA(_info_, _c_, _h_, _s_, _lba_) \ (_lba_=(((_c_)*(_info_)->heads_num+(_h_))*(_info_)->sectors_num)+(_s_)-1)
// ---------------------------------------------------------------------------
static Cyg_ErrNo disk_bread(cyg_io_handle_t handle,
void *buf,
cyg_uint32 *len,
cyg_uint32 pos);
static Cyg_ErrNo disk_bwrite(cyg_io_handle_t handle,
const void *buf,
cyg_uint32 *len,
cyg_uint32 pos);
static Cyg_ErrNo disk_select(cyg_io_handle_t handle,
cyg_uint32 which,
CYG_ADDRWORD info);
static Cyg_ErrNo disk_get_config(cyg_io_handle_t handle,
cyg_uint32 key,
void *buf,
cyg_uint32 *len);
static Cyg_ErrNo disk_set_config(cyg_io_handle_t handle,
cyg_uint32 key,
const void *buf,
cyg_uint32 *len);
BLOCK_DEVIO_TABLE(cyg_io_disk_devio,
disk_bwrite,
disk_bread,
disk_select,
disk_get_config,
disk_set_config
);
static cyg_bool disk_init(struct cyg_devtab_entry *tab);
static Cyg_ErrNo disk_connected(struct cyg_devtab_entry *tab,
cyg_disk_identify_t *ident);
static Cyg_ErrNo disk_disconnected(struct cyg_devtab_entry *tab);
static Cyg_ErrNo disk_lookup(struct cyg_devtab_entry **tab,
struct cyg_devtab_entry *sub_tab,
const char *name);
DISK_CALLBACKS(cyg_io_disk_callbacks,
disk_init,
disk_connected,
disk_disconnected,
disk_lookup
);
// ---------------------------------------------------------------------------
//
// Read partition from data
//
static void
read_partition(cyg_uint8 *data,
cyg_disk_info_t *info,
cyg_disk_partition_t *part)
{
cyg_uint16 c, h, s;
part->type = data[4];
part->state = data[0];
READ_CHS(&data[1], c, h, s);
CHS_TO_LBA(&info->ident, c, h, s, part->start);
READ_CHS(&data[5], c, h, s);
CHS_TO_LBA(&info->ident, c, h, s, part->end);
READ_DWORD(&data[12], part->size);
}
//
// Read Master Boot Record (partitions)
//
static Cyg_ErrNo
read_mbr(disk_channel *chan)
{
cyg_disk_info_t *info = chan->info;
disk_funs *funs = chan->funs;
cyg_uint8 buf[512];
Cyg_ErrNo res = ENOERR;
int i;
for (i = 0; i < MBR_PART_NUM; i++)
info->partitions[i].type = 0x00;
res = (funs->read)(chan, (void *)buf, 512, 0);
if (ENOERR != res)
return res;
if (MBR_SIG_BYTE0 == buf[MBR_SIG_ADDR+0] && MBR_SIG_BYTE1 == buf[MBR_SIG_ADDR+1])
{
D(("disk MBR found\n"));
for (i = 0; i < MBR_PART_NUM; i++)
{
cyg_disk_partition_t *part = &info->partitions[i];
read_partition(&buf[MBR_PART_ADDR+MBR_PART_SIZE*i], info, part);
#ifdef DEBUG
if (0x00 != part->type)
{
D(("\ndisk MBR partition %d:\n", i));
D((" type = %02X\n", part->type));
D((" state = %02X\n", part->state));
D((" start = %d\n", part->start));
D((" end = %d\n", part->end));
D((" size = %d\n\n", part->size));
}
#endif
}
}
return ENOERR;
}
static cyg_bool
disk_init(struct cyg_devtab_entry *tab)
{
disk_channel *chan = (disk_channel *) tab->priv;
cyg_disk_info_t *info = chan->info;
int i;
if (!chan->init)
{
info->connected = false;
// clear devices array (one per partition)
// and partition data
for (i = 0; i < MBR_PART_NUM; i++)
{
info->devs[i] = (cyg_addrword_t) 0;
info->partitions[i].type = 0x00;
}
chan->init = true;
}
return true;
}
static Cyg_ErrNo
disk_connected(struct cyg_devtab_entry *tab,
cyg_disk_identify_t *ident)
{
disk_channel *chan = (disk_channel *) tab->priv;
cyg_disk_info_t *info = chan->info;
Cyg_ErrNo res = ENOERR;
if (!chan->init)
return -EINVAL;
info->ident = *ident;
info->block_size = 512;
info->blocks_num = ident->lba_sectors_num;
D(("disk connected\n"));
D((" serial = '%s'\n", ident->serial));
D((" firmware rev = '%s'\n", ident->firmware_rev));
D((" model num = '%s'\n", ident->model_num));
D((" block_size = %d\n", info->block_size));
D((" blocks_num = %d\n", info->blocks_num));
if (chan->mbr_support)
{
// read disk master boot record
res = read_mbr(chan);
}
if (ENOERR == res)
{
// now declare that we are connected
info->connected = true;
chan->valid = true;
}
return res;
}
static Cyg_ErrNo
disk_disconnected(struct cyg_devtab_entry *tab)
{
disk_channel *chan = (disk_channel *) tab->priv;
cyg_disk_info_t *info = chan->info;
int i;
if (!chan->init)
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