/*
* linux/drivers/scsi/ide-scsi.c Version 0.3 - ALPHA Jul 24, 1997
*
* Copyright (C) 1996, 1997 Gadi Oxman <gadio@netvision.net.il>
*/
/*
* Emulation of a SCSI host adapter for IDE ATAPI devices.
*
* With this driver, one can use the Linux SCSI drivers instead of the
* native IDE ATAPI drivers.
*
* Ver 0.1 Dec 3 96 Initial version.
* Ver 0.2 Jan 26 97 Fixed bug in cleanup_module() and added emulation
* of MODE_SENSE_6/MODE_SELECT_6 for cdroms. Thanks
* to Janos Farkas for pointing this out.
* Avoid using bitfields in structures for m68k.
* Added Scather/Gather and DMA support.
* Ver 0.3 Jul 24 97 Add support for ATAPI PD/CD drives.
*/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/malloc.h>
#include <asm/io.h>
#include <asm/bitops.h>
#include "../block/ide.h"
#include "scsi.h"
#include "hosts.h"
#include "sd.h"
#include "ide-scsi.h"
#define IDESCSI_DEBUG_LOG 0
typedef struct idescsi_pc_s {
u8 c[12]; /* Actual packet bytes */
int request_transfer; /* Bytes to transfer */
int actually_transferred; /* Bytes actually transferred */
int buffer_size; /* Size of our data buffer */
struct request *rq; /* The corresponding request */
byte *buffer; /* Data buffer */
byte *current_position; /* Pointer into the above buffer */
struct scatterlist *sg; /* Scather gather table */
int b_count; /* Bytes transferred from current entry */
Scsi_Cmnd *scsi_cmd; /* SCSI command */
void (*done)(Scsi_Cmnd *); /* Scsi completion routine */
unsigned int flags; /* Status/Action flags */
} idescsi_pc_t;
/*
* Packet command status bits.
*/
#define PC_DMA_IN_PROGRESS 0 /* 1 while DMA in progress */
#define PC_WRITING 1 /* Data direction */
typedef struct {
ide_drive_t *drive;
idescsi_pc_t *pc; /* Current packet command */
unsigned int flags; /* Status/Action flags */
int media;
} idescsi_scsi_t;
/*
* Per ATAPI device status bits.
*/
#define IDESCSI_DRQ_INTERRUPT 0 /* DRQ interrupt device */
/*
* ide-scsi requests.
*/
#define IDESCSI_PC_RQ 90
/*
* Bits of the interrupt reason register.
*/
#define IDESCSI_IREASON_COD 0x1 /* Information transferred is command */
#define IDESCSI_IREASON_IO 0x2 /* The device requests us to read */
#define IDE_MIN(a,b) ((a)<(b) ? (a):(b))
#define IDE_MAX(a,b) ((a)>(b) ? (a):(b))
static void idescsi_discard_data (ide_drive_t *drive, unsigned int bcount)
{
while (bcount--)
IN_BYTE (IDE_DATA_REG);
}
static void idescsi_output_zeros (ide_drive_t *drive, unsigned int bcount)
{
while (bcount--)
OUT_BYTE (0, IDE_DATA_REG);
}
/*
* PIO data transfer routines using the scather gather table.
*/
static void idescsi_input_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount)
{
int count;
while (bcount) {
if (pc->sg - (struct scatterlist *) pc->scsi_cmd->request_buffer > pc->scsi_cmd->use_sg) {
printk (KERN_ERR "ide-scsi: scather gather table too small, discarding data\n");
idescsi_discard_data (drive, bcount);
return;
}
count = IDE_MIN (pc->sg->length - pc->b_count, bcount);
atapi_input_bytes (drive, pc->sg->address + pc->b_count, count);
bcount -= count; pc->b_count += count;
if (pc->b_count == pc->sg->length) {
pc->sg++;
pc->b_count = 0;
}
}
}
static void idescsi_output_buffers (ide_drive_t *drive, idescsi_pc_t *pc, unsigned int bcount)
{
int count;
while (bcount) {
if (pc->sg - (struct scatterlist *) pc->scsi_cmd->request_buffer > pc->scsi_cmd->use_sg) {
printk (KERN_ERR "ide-scsi: scather gather table too small, padding with zeros\n");
idescsi_output_zeros (drive, bcount);
return;
}
count = IDE_MIN (pc->sg->length - pc->b_count, bcount);
atapi_output_bytes (drive, pc->sg->address + pc->b_count, count);
bcount -= count; pc->b_count += count;
if (pc->b_count == pc->sg->length) {
pc->sg++;
pc->b_count = 0;
}
}
}
/*
* Most of the SCSI commands are supported directly by ATAPI devices.
* idescsi_transform_pc handles the few exceptions.
*/
static inline void idescsi_transform_pc1 (ide_drive_t *drive, idescsi_pc_t *pc)
{
idescsi_scsi_t *scsi = drive->scsi;
u8 *c = pc->c, *buf = pc->buffer, *sc = pc->scsi_cmd->cmnd;
int i;
if (scsi->media == TYPE_ROM) {
if (c[0] == READ_6 || c[0] == WRITE_6) {
c[8] = c[4]; c[5] = c[3]; c[4] = c[2];
c[3] = c[1] & 0x1f; c[2] = 0; c[1] &= 0xe0;
c[0] += (READ_10 - READ_6);
}
if (c[0] == MODE_SENSE || (c[0] == MODE_SELECT && buf[3] == 8)) {
pc->request_transfer -= 4;
memset (c, 0, 12);
c[0] = sc[0] | 0x40; c[2] = sc[2]; c[8] = sc[4] - 4;
if (c[0] == MODE_SENSE_10) return;
for (i = 0; i <= 7; i++) buf[i] = 0;
for (i = 8; i < pc->buffer_size - 4; i++) buf[i] = buf[i + 4];
}
}
}
static inline void idescsi_transform_pc2 (ide_drive_t *drive, idescsi_pc_t *pc)
{
idescsi_scsi_t *scsi = drive->scsi;
u8 *buf = pc->buffer;
int i;
if (scsi->media == TYPE_ROM) {
if (pc->c[0] == MODE_SENSE_10 && pc->scsi_cmd->cmnd[0] == MODE_SENSE) {
buf[0] = buf[1]; buf[1] = buf[2];
buf[2] = 0; buf[3] = 8;
for (i = pc->buffer_size - 1; i >= 12; i--) buf[i] = buf[i - 4];
for (i = 11; i >= 4; i--) buf[i] = 0;
}
if (pc->c[0] == INQUIRY)
buf[2] |= 2;
}
}
static inline void idescsi_free_bh (struct buffer_head *bh)
{
struct buffer_head *bhp;
while (bh) {
bhp = bh;
bh = bh->b_reqnext;
kfree (bhp);
}
}
void idescsi_end_request (byte uptodate, ide_hwgroup_t *hwgroup)
{
ide_drive_t *drive = hwgroup->drive;
idescsi_scsi_t *scsi = drive->scsi;
struct request *rq = hwgroup->rq;
idescsi_pc_t *pc = (idescsi_pc_t *) rq->buffer;
if (rq->cmd != IDESCSI_PC_RQ) {
ide_end_request (uptodate, hwgroup);
return;
}
ide_end_drive_cmd (drive, 0, 0);
if (rq->errors >= ERROR_MAX) {
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: I/O error for %lu\n", drive->name, pc->scsi_cmd->serial_number);
#endif /* IDESCSI_DEBUG_LOG */
pc->scsi_cmd->result = DID_ERROR << 16;
} else if (rq->errors) {
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: check condition for %lu\n", drive->name, pc->scsi_cmd->serial_number);
#endif /* IDESCSI_DEBUG_LOG */
pc->scsi_cmd->result = (CHECK_CONDITION << 1) | (DID_OK << 16);
} else {
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: success for %lu\n", drive->name, pc->scsi_cmd->serial_number);
#endif /* IDESCSI_DEBUG_LOG */
pc->scsi_cmd->result = DID_OK << 16;
idescsi_transform_pc2 (drive, pc);
}
pc->done(pc->scsi_cmd);
idescsi_free_bh (rq->bh);
kfree(pc); kfree(rq);
scsi->pc = NULL;
}
/*
* Our interrupt handler.
*/
static void idescsi_pc_intr (ide_drive_t *drive)
{
idescsi_scsi_t *scsi = drive->scsi;
byte status, ireason;
int bcount;
idescsi_pc_t *pc=scsi->pc;
struct request *rq = pc->rq;
unsigned int temp;
#if IDESCSI_DEBUG_LOG
printk (KERN_INFO "ide-scsi: Reached idescsi_pc_intr interrupt handler\n");
#endif /* IDESCSI_DEBUG_LOG */
if (clear_bit (PC_DMA_IN_PROGRESS, &pc->flags)) {
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: DMA complete\n", drive->name);
#endif /* IDESCSI_DEBUG_LOG */
pc->actually_transferred=pc->request_transfer;
(void) (HWIF(drive)->dmaproc(ide_dma_abort, drive));
}
status = GET_STAT(); /* Clear the interrupt */
if ((status & DRQ_STAT) == 0) { /* No more interrupts */
#if IDESCSI_DEBUG_LOG
printk (KERN_INFO "Packet command completed, %d bytes transferred\n", pc->actually_transferred);
#endif /* IDESCSI_DEBUG_LOG */
sti();
if (status & ERR_STAT)
rq->errors++;
idescsi_end_request (1, HWGROUP(drive));
return;
}
bcount = IN_BYTE (IDE_BCOUNTH_REG) << 8 | IN_BYTE (IDE_BCOUNTL_REG);
ireason = IN_BYTE (IDE_IREASON_REG);
if (ireason & IDESCSI_IREASON_COD) {
printk (KERN_ERR "ide-scsi: CoD != 0 in idescsi_pc_intr\n");
ide_do_reset (drive);
return;
}
if (ireason & IDESCSI_IREASON_IO) {
temp = pc->actually_transferred + bcount;
if ( temp > pc->request_transfer) {
if (temp > pc->buffer_size) {
printk (KERN_ERR "ide-scsi: The scsi wants to send us more data than expected - discarding data\n");
idescsi_discard_data (drive,bcount);
ide_set_handler (drive,&idescsi_pc_intr,WAIT_CMD);
return;
}
#if IDESCSI_DEBUG_LOG
printk (KERN_NOTICE "ide-scsi: The scsi wants to send us more data than expected - allowing transfer\n");
#endif /* IDESCSI_DEBUG_LOG */
}
}
if (ireason & IDESCSI_IREASON_IO) {
if (pc->sg)
idescsi_input_buffers (drive, pc, bcount);
else
atapi_input_bytes (drive,pc->current_position,bcount);
} else {
if (pc->sg)
idescsi_output_buffers (drive, pc, bcount);
else
atapi_output_bytes (drive,pc->current_position,bcount);
}
pc->actually_transferred+=bcount; /* Update the current position */
pc->current_position+=bcount;
ide_set_handler (drive,&idescsi_pc_intr,WAIT_CMD); /* And set the interrupt handler again */
}
static void idescsi_transfer_pc (ide_drive_t *drive)
{
idescsi_scsi_t *scsi = drive->scsi;
byte ireason;
if (ide_wait_stat (drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) {
printk (KERN_ERR "ide-scsi: Strange, packet command initiated yet DRQ isn't asserted\n");
return;
}
ireason = IN_BYTE (IDE_IREASON_REG);
if ((ireason & (IDESCSI_IREASON_IO | IDESCSI_IREASON_COD)) != IDESCSI_IREASON_COD) {
printk (KERN_ERR "ide-scsi: (IO,CoD) != (0,1) while issuing a packet command\n");
ide_do_reset (drive);
return;
}
ide_set_handler (drive, &idescsi_pc_intr, WAIT_CMD); /* Set the interrupt routine */
atapi_output_bytes (drive, scsi->pc->c, 12); /* Send the actual packet */
}
/*
* Issue a packet command
*/
static void idescsi_issue_pc (ide_drive_t *drive, idescsi_pc_t *pc)
{
idescsi_scsi_t *scsi = drive->scsi;
int bcount;
struct request *rq = pc->rq;
int dma_ok = 0;
scsi->pc=pc; /* Set the current packet command */
pc->actually_transferred=0; /* We haven't transferred any data yet */
pc->current_position=pc->buffer;
bcount = IDE_MIN (pc->request_transfer, 63 * 1024); /* Request to transfer the entire buffer at once */
if (drive->using_dma && rq->bh)
dma_ok=!HWIF(drive)->dmaproc(test_bit (PC_WRITING, &pc->flags) ? ide_dma_write : ide_dma_read, drive);
OUT_BYTE (drive->ctl,IDE_CONTROL_REG);
OUT_BYTE (dma_ok,IDE_FEATURE_REG);
OUT_BYTE (bcount >> 8,IDE_BCOUNTH_REG);
OUT_BYTE (bcount & 0xff,IDE_BCOUNTL_REG);
OUT_BYTE (drive->select.all,IDE_SELECT_REG);
if (dma_ok) {
set_bit (PC_DMA_IN_PROGRESS, &pc->flags);
(void) (HWIF(drive)->dmaproc(ide_dma_begin, drive));
}
if (test_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags)) {
ide_set_handler (drive, &idescsi_transfer_pc, WAIT_CMD);
OUT_BYTE (WIN_PACKETCMD, IDE_COMMAND_REG); /* Issue the packet command */
} else {
OUT_BYTE (WIN_PACKETCMD, IDE_COMMAND_REG);
idescsi_transfer_pc (drive);
}
}
/*
* idescsi_do_request is our request handling function.
*/
void idescsi_do_request (ide_drive_t *drive, struct request *rq, unsigned long block)
{
#if IDESCSI_DEBUG_LOG
printk (KERN_INFO "rq_status: %d, rq_dev: %u, cmd: %d, errors: %d\n",rq->rq_status,(unsigned int) rq->rq_dev,rq->cmd,rq->errors);
printk (KERN_INFO "sector: %ld, nr_sectors: %ld, current_nr_sectors: %ld\n",rq->sector,rq->nr_sectors,rq->current_nr_sectors);
#endif /* IDESCSI_DEBUG_LOG */
if (rq->cmd == IDESCSI_PC_RQ) {
idescsi_issue_pc (drive, (idescsi_pc_t *) rq->buffer);
return;
}
printk (KERN_ERR "ide-scsi: %s: unsupported command in request queue (%x)\n", drive->name, rq->cmd);
idescsi_end_request (0,HWGROUP (drive));
}
int idescsi_open (struct inode *inode, struct file *filp, ide_drive_t *drive)
{
MOD_INC_USE_COUNT;
return 0;
}
void idescsi_ide_release (struct inode *inode, struct file *filp, ide_drive_t *drive)
{
MOD_DEC_USE_COUNT;
}
static ide_drive_t *idescsi_drives[MAX_HWIFS * MAX_DRIVES];
static int idescsi_initialized = 0;
int idescsi_ioctl (ide_drive_t *drive, struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
return -EINVAL;
}
static struct proc_dir_entry idescsi_proc_dir = {PROC_SCSI_IDESCSI, 8, "ide-scsi", S_IFDIR | S_IRUGO | S_IXUGO, 2};
/*
* idescsi_setup will register the driver for each scsi.
*/
void idescsi_setup (ide_drive_t *drive)
{
idescsi_scsi_t *scsi;
int i, id;
if (!idescsi_initialized) {
idescsi_initialized = 1;
for (i = 0; i < MAX_HWIFS * MAX_DRIVES; i++)
idescsi_drives[i] = NULL;
}
if ((scsi = (idescsi_scsi_t *) kmalloc (sizeof (idescsi_scsi_t), GFP_KERNEL)) == NULL) {
printk (KERN_ERR "ide-scsi: %s: Can't allocate a scsi structure\n", drive->name);
return;
}
for (id = 0; id < MAX_HWIFS * MAX_DRIVES && idescsi_drives[id]; id++);
idescsi_drives[id] = drive;
drive->scsi = scsi;
drive->ready_stat = 0;
memset (scsi, 0, sizeof (idescsi_scsi_t));
scsi->drive = drive;
scsi->media = (drive->id->config >> 8) & 0x1f;
if (drive->id && (drive->id->config & 0x0060) == 0x20)
set_bit (IDESCSI_DRQ_INTERRUPT, &scsi->flags);
}
int idescsi_detect (Scsi_Host_Template *host_template)
{
struct Scsi_Host *host;
int id;
host_template->proc_dir = &idescsi_proc_dir;
host = scsi_register(host_template, 0);
for (id = 0; id < MAX_HWIFS * MAX_DRIVES && idescsi_drives[id]; id++);
host->max_id = id;
host->can_queue = host->cmd_per_lun * id;
return 1;
}
int idescsi_release (struct Scsi_Host *host)
{
return 0;
}
const char *idescsi_info (struct Scsi_Host *host)
{
return "SCSI host adapter emulation for IDE ATAPI devices";
}
static inline struct buffer_head *idescsi_kmalloc_bh (int count)
{
struct buffer_head *bh, *bhp, *first_bh;
if ((first_bh = bhp = bh = kmalloc (sizeof(struct buffer_head), GFP_ATOMIC)) == NULL)
goto abort;
memset (bh, 0, sizeof (struct buffer_head));
bh->b_reqnext = NULL;
while (--count) {
if ((bh = kmalloc (sizeof(struct buffer_head), GFP_ATOMIC)) == NULL)
goto abort;
memset (bh, 0, sizeof (struct buffer_head));
bhp->b_reqnext = bh;
bhp = bh;
bh->b_reqnext = NULL;
}
return first_bh;
abort:
idescsi_free_bh (first_bh);
return NULL;
}
static inline int idescsi_set_direction (idescsi_pc_t *pc)
{
switch (pc->c[0]) {
case READ_6: case READ_10: case READ_12:
clear_bit (PC_WRITING, &pc->flags);
return 0;
case WRITE_6: case WRITE_10: case WRITE_12:
set_bit (PC_WRITING, &pc->flags);
return 0;
default:
return 1;
}
}
static inline struct buffer_head *idescsi_dma_bh (ide_drive_t *drive, idescsi_pc_t *pc)
{
struct buffer_head *bh = NULL, *first_bh = NULL;
int segments = pc->scsi_cmd->use_sg;
struct scatterlist *sg = pc->scsi_cmd->request_buffer;
if (!drive->using_dma || pc->request_transfer % 1024)
return NULL;
if (idescsi_set_direction(pc))
return NULL;
if (segments) {
if ((first_bh = bh = idescsi_kmalloc_bh (segments)) == NULL)
return NULL;
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: building DMA table, %d segments, %dkB total\n", drive->name, segments, pc->request_transfer >> 10);
#endif /* IDESCSI_DEBUG_LOG */
while (segments--) {
bh->b_data = sg->address;
bh->b_size = sg->length;
bh = bh->b_reqnext;
sg++;
}
} else {
if ((first_bh = bh = idescsi_kmalloc_bh (1)) == NULL)
return NULL;
#if IDESCSI_DEBUG_LOG
printk ("ide-scsi: %s: building DMA table for a single buffer (%dkB)\n", drive->name, pc->request_transfer >> 10);
#endif /* IDESCSI_DEBUG_LOG */
bh->b_data = pc->scsi_cmd->request_buffer;
bh->b_size = pc->request_transfer;
}
return first_bh;
}
int idescsi_queue (Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
{
ide_drive_t *drive = idescsi_drives[cmd->target];
struct request *rq = NULL;
idescsi_pc_t *pc = NULL;
#if IDESCSI_DEBUG_LOG
printk ("idescsi_queue called, serial = %lu, cmd[0] = %x, id = %d\n", cmd->serial_number, cmd->cmnd[0], cmd->target);
#endif /* IDESCSI_DEBUG_LOG */
if (!drive) {
printk (KERN_ERR "ide-scsi: drive id %d not present\n", cmd->target);
goto abort;
}
pc = kmalloc (sizeof (idescsi_pc_t), GFP_ATOMIC);
rq = kmalloc (sizeof (struct request), GFP_ATOMIC);
if (rq == NULL || pc == NULL) {
printk (KERN_ERR "ide-scsi: %s: out of memory\n", drive->name);
goto abort;
}
memset (pc->c, 0, 12);
pc->flags = 0;
pc->rq = rq;
memcpy (pc->c, cmd->cmnd, cmd->cmd_len);
if (cmd->use_sg) {
pc->buffer = NULL;
pc->sg = cmd->request_buffer;
} else {
pc->buffer = cmd->request_buffer;
pc->sg = NULL;
}
pc->b_count = 0;
pc->request_transfer = pc->buffer_size = cmd->request_bufflen;
pc->scsi_cmd = cmd;
pc->done = done;
idescsi_transform_pc1 (drive, pc);
ide_init_drive_cmd (rq);
rq->buffer = (char *) pc;
rq->bh = idescsi_dma_bh (drive, pc);
rq->cmd = IDESCSI_PC_RQ;
(void) ide_do_drive_cmd (drive, rq, ide_end);
return 0;
abort:
if (pc) kfree (pc);
if (rq) kfree (rq);
cmd->result = DID_ERROR << 16;
done(cmd);
return 0;
}
int idescsi_abort (Scsi_Cmnd *cmd)
{
return SCSI_ABORT_SNOOZE;
}
int idescsi_reset (Scsi_Cmnd *cmd, unsigned int resetflags)
{
return SCSI_RESET_PUNT;
}
int idescsi_bios (Disk *disk, kdev_t dev, int *parm)
{
ide_drive_t *drive = idescsi_drives[disk->device->id];
if (drive->cyl && drive->head && drive->sect) {
parm[0] = drive->head;
parm[1] = drive->sect;
parm[2] = drive->cyl;
}
return 0;
}
