at_wini.c

minix3的源码

 *===========================================================================*/
PRIVATE int w_transfer(proc_nr, opcode, position, iov, nr_req)
int proc_nr;			/* process doing the request */
int opcode;			/* DEV_GATHER or DEV_SCATTER */
off_t position;			/* offset on device to read or write */
iovec_t *iov;			/* pointer to read or write request vector */
unsigned nr_req;		/* length of request vector */
{
  struct wini *wn = w_wn;
  iovec_t *iop, *iov_end = iov + nr_req;
  int r, s, errors;
  unsigned long block;
  unsigned long dv_size = cv64ul(w_dv->dv_size);
  unsigned cylinder, head, sector, nbytes;

#if ENABLE_ATAPI
  if (w_wn->state & ATAPI) {
	return atapi_transfer(proc_nr, opcode, position, iov, nr_req);
  }
#endif

  

  /* Check disk address. */
  if ((position & SECTOR_MASK) != 0) return(EINVAL);

  errors = 0;

  while (nr_req > 0) {
	/* How many bytes to transfer? */
	nbytes = 0;
	for (iop = iov; iop < iov_end; iop++) nbytes += iop->iov_size;
	if ((nbytes & SECTOR_MASK) != 0) return(EINVAL);

	/* Which block on disk and how close to EOF? */
	if (position >= dv_size) return(OK);		/* At EOF */
	if (position + nbytes > dv_size) nbytes = dv_size - position;
	block = div64u(add64ul(w_dv->dv_base, position), SECTOR_SIZE);

	if (nbytes >= wn->max_count) {
		/* The drive can't do more then max_count at once. */
		nbytes = wn->max_count;
	}

	/* First check to see if a reinitialization is needed. */
	if (!(wn->state & INITIALIZED) && w_specify() != OK) return(EIO);

	/* Tell the controller to transfer nbytes bytes. */
	r = do_transfer(wn, wn->precomp, ((nbytes >> SECTOR_SHIFT) & BYTE),
		block, opcode);

	while (r == OK && nbytes > 0) {
		/* For each sector, wait for an interrupt and fetch the data
		 * (read), or supply data to the controller and wait for an
		 * interrupt (write).
		 */

		if (opcode == DEV_GATHER) {
			/* First an interrupt, then data. */
			if ((r = at_intr_wait()) != OK) {
				/* An error, send data to the bit bucket. */
				if (w_wn->w_status & STATUS_DRQ) {
	if ((s=sys_insw(wn->base_cmd + REG_DATA, SELF, tmp_buf, SECTOR_SIZE)) != OK)
		panic(w_name(),"Call to sys_insw() failed", s);
				}
				break;
			}
		}

		/* Wait for data transfer requested. */
		if (!w_waitfor(STATUS_DRQ, STATUS_DRQ)) { r = ERR; break; }

		/* Copy bytes to or from the device's buffer. */
		if (opcode == DEV_GATHER) {
	if ((s=sys_insw(wn->base_cmd + REG_DATA, proc_nr, (void *) iov->iov_addr, SECTOR_SIZE)) != OK)
		panic(w_name(),"Call to sys_insw() failed", s);
		} else {
	if ((s=sys_outsw(wn->base_cmd + REG_DATA, proc_nr, (void *) iov->iov_addr, SECTOR_SIZE)) != OK)
		panic(w_name(),"Call to sys_insw() failed", s);

			/* Data sent, wait for an interrupt. */
			if ((r = at_intr_wait()) != OK) break;
		}

		/* Book the bytes successfully transferred. */
		nbytes -= SECTOR_SIZE;
		position += SECTOR_SIZE;
		iov->iov_addr += SECTOR_SIZE;
		if ((iov->iov_size -= SECTOR_SIZE) == 0) { iov++; nr_req--; }
	}

	/* Any errors? */
	if (r != OK) {
		/* Don't retry if sector marked bad or too many errors. */
		if (r == ERR_BAD_SECTOR || ++errors == max_errors) {
			w_command = CMD_IDLE;
			return(EIO);
		}
	}
  }

  w_command = CMD_IDLE;
  return(OK);
}

/*===========================================================================*
 *				com_out					     *
 *===========================================================================*/
PRIVATE int com_out(cmd)
struct command *cmd;		/* Command block */
{
/* Output the command block to the winchester controller and return status */

  struct wini *wn = w_wn;
  unsigned base_cmd = wn->base_cmd;
  unsigned base_ctl = wn->base_ctl;
  pvb_pair_t outbyte[7];		/* vector for sys_voutb() */
  int s;				/* status for sys_(v)outb() */

  if (w_wn->state & IGNORING) return ERR;

  if (!w_waitfor(STATUS_BSY, 0)) {
	printf("%s: controller not ready\n", w_name());
	return(ERR);
  }

  /* Select drive. */
  if ((s=sys_outb(base_cmd + REG_LDH, cmd->ldh)) != OK)
  	panic(w_name(),"Couldn't write register to select drive",s);

  if (!w_waitfor(STATUS_BSY, 0)) {
	printf("%s: com_out: drive not ready\n", w_name());
	return(ERR);
  }

  /* Schedule a wakeup call, some controllers are flaky. This is done with
   * a synchronous alarm. If a timeout occurs a SYN_ALARM message is sent
   * from HARDWARE, so that w_intr_wait() can call w_timeout() in case the
   * controller was not able to execute the command. Leftover timeouts are
   * simply ignored by the main loop. 
   */
  sys_setalarm(wakeup_ticks, 0);

  wn->w_status = STATUS_ADMBSY;
  w_command = cmd->command;
  pv_set(outbyte[0], base_ctl + REG_CTL, wn->pheads >= 8 ? CTL_EIGHTHEADS : 0);
  pv_set(outbyte[1], base_cmd + REG_PRECOMP, cmd->precomp);
  pv_set(outbyte[2], base_cmd + REG_COUNT, cmd->count);
  pv_set(outbyte[3], base_cmd + REG_SECTOR, cmd->sector);
  pv_set(outbyte[4], base_cmd + REG_CYL_LO, cmd->cyl_lo);
  pv_set(outbyte[5], base_cmd + REG_CYL_HI, cmd->cyl_hi);
  pv_set(outbyte[6], base_cmd + REG_COMMAND, cmd->command);
  if ((s=sys_voutb(outbyte,7)) != OK)
  	panic(w_name(),"Couldn't write registers with sys_voutb()",s);
  return(OK);
}

/*===========================================================================*
 *				w_need_reset				     *
 *===========================================================================*/
PRIVATE void w_need_reset()
{
/* The controller needs to be reset. */
  struct wini *wn;
  int dr = 0;

  for (wn = wini; wn < &wini[MAX_DRIVES]; wn++, dr++) {
	if (wn->base_cmd == w_wn->base_cmd) {
		wn->state |= DEAF;
		wn->state &= ~INITIALIZED;
	}
  }
}

/*===========================================================================*
 *				w_do_close				     *
 *===========================================================================*/
PRIVATE int w_do_close(dp, m_ptr)
struct driver *dp;
message *m_ptr;
{
/* Device close: Release a device. */
  if (w_prepare(m_ptr->DEVICE) == NIL_DEV)
  	return(ENXIO);
  w_wn->open_ct--;
#if ENABLE_ATAPI
  if (w_wn->open_ct == 0 && (w_wn->state & ATAPI)) atapi_close();
#endif
  return(OK);
}

/*===========================================================================*
 *				com_simple				     *
 *===========================================================================*/
PRIVATE int com_simple(cmd)
struct command *cmd;		/* Command block */
{
/* A simple controller command, only one interrupt and no data-out phase. */
  int r;

  if (w_wn->state & IGNORING) return ERR;

  if ((r = com_out(cmd)) == OK) r = at_intr_wait();
  w_command = CMD_IDLE;
  return(r);
}

/*===========================================================================*
 *				w_timeout				     *
 *===========================================================================*/
PRIVATE void w_timeout(void)
{
  struct wini *wn = w_wn;

  switch (w_command) {
  case CMD_IDLE:
	break;		/* fine */
  case CMD_READ:
  case CMD_WRITE:
	/* Impossible, but not on PC's:  The controller does not respond. */

	/* Limiting multisector I/O seems to help. */
	if (wn->max_count > 8 * SECTOR_SIZE) {
		wn->max_count = 8 * SECTOR_SIZE;
	} else {
		wn->max_count = SECTOR_SIZE;
	}
	/*FALL THROUGH*/
  default:
	/* Some other command. */
	if (w_testing)  wn->state |= IGNORING;	/* Kick out this drive. */
	else if (!w_silent) printf("%s: timeout on command %02x\n", w_name(), w_command);
	w_need_reset();
	wn->w_status = 0;
  }
}

/*===========================================================================*
 *				w_reset					     *
 *===========================================================================*/
PRIVATE int w_reset()
{
/* Issue a reset to the controller.  This is done after any catastrophe,
 * like the controller refusing to respond.
 */
  int s;
  struct wini *wn = w_wn;

  /* Don't bother if this drive is forgotten. */
  if (w_wn->state & IGNORING) return ERR;

  /* Wait for any internal drive recovery. */
  tickdelay(RECOVERY_TICKS);

  /* Strobe reset bit */
  if ((s=sys_outb(wn->base_ctl + REG_CTL, CTL_RESET)) != OK)
  	panic(w_name(),"Couldn't strobe reset bit",s);
  tickdelay(DELAY_TICKS);
  if ((s=sys_outb(wn->base_ctl + REG_CTL, 0)) != OK)
  	panic(w_name(),"Couldn't strobe reset bit",s);
  tickdelay(DELAY_TICKS);

  /* Wait for controller ready */
  if (!w_waitfor(STATUS_BSY, 0)) {
	printf("%s: reset failed, drive busy\n", w_name());
	return(ERR);
  }

  /* The error register should be checked now, but some drives mess it up. */

  for (wn = wini; wn < &wini[MAX_DRIVES]; wn++) {
	if (wn->base_cmd == w_wn->base_cmd) {
		wn->state &= ~DEAF;
  		if (w_wn->irq_need_ack) {
		    	/* Make sure irq is actually enabled.. */
	  		sys_irqenable(&w_wn->irq_hook_id);
		}
	}
  }
		

  return(OK);
}

/*===========================================================================*
 *				w_intr_wait				     *
 *===========================================================================*/
PRIVATE void w_intr_wait()
{
/* Wait for a task completion interrupt. */

  message m;

  if (w_wn->irq != NO_IRQ) {
	/* Wait for an interrupt that sets w_status to "not busy". */
	while (w_wn->w_status & (STATUS_ADMBSY|STATUS_BSY)) {
		receive(ANY, &m);		/* expect HARD_INT message */
		if (m.m_type == SYN_ALARM) { 	/* but check for timeout */
		    w_timeout();		/* a.o. set w_status */
		} else if (m.m_type == HARD_INT) {
		    sys_inb(w_wn->base_cmd + REG_STATUS, &w_wn->w_status);
		    ack_irqs(m.NOTIFY_ARG);
		} else if (m.m_type == DEV_PING) {
		    notify(m.m_source);
	        } else {
	        	printf("AT_WINI got unexpected message %d from %d\n",
	        		m.m_type, m.m_source);
	        }
	}
  } else {
	/* Interrupt not yet allocated; use polling. */
	(void) w_waitfor(STATUS_BSY, 0);
  }
}

/*===========================================================================*
 *				at_intr_wait				     *
 *===========================================================================*/
PRIVATE int at_intr_wait()
{
/* Wait for an interrupt, study the status bits and return error/success. */
  int r;
  int s,inbval;		/* read value with sys_inb */ 

  w_intr_wait();
  if ((w_wn->w_status & (STATUS_BSY | STATUS_WF | STATUS_ERR)) == 0) {
	r = OK;
  } else {
  	if ((s=sys_inb(w_wn->base_cmd + REG_ERROR, &inbval)) != OK)
  		panic(w_name(),"Couldn't read register",s);
  	if ((w_wn->w_status & STATUS_ERR) && (inbval & ERROR_BB)) {
  		r = ERR_BAD_SECTOR;	/* sector marked bad, retries won't help */
  	} else {
  		r = ERR;		/* any other error */
  	}
  }
  w_wn->w_status |= STATUS_ADMBSY;	/* assume still busy with I/O */
  return(r);
}

/*===========================================================================*
 *				w_waitfor				     *
 *===========================================================================*/
PRIVATE int w_waitfor(mask, value)
int mask;			/* status mask */
int value;			/* required status */
{
/* Wait until controller is in the required state.  Return zero on timeout.
 * An alarm that set a timeout flag is used. TIMEOUT is in micros, we need
 * ticks. Disabling the alarm is not needed, because a static flag is used
 * and a leftover timeout cannot do any harm.
 */
  clock_t t0, t1;
  int s;
  getuptime(&t0);
  do {
	if ((s=sys_inb(w_wn->base_cmd + REG_STATUS, &w_wn->w_status)) != OK)
		panic(w_name(),"Couldn't read register",s);
	if ((w_wn->w_status & mask) == value) {
        	return 1;
	}
  } while ((s=getuptime(&t1)) == OK && (t1-t0) < timeout_ticks );
  if (OK != s) printf("AT_WINI: warning, get_uptime failed: %d\n",s);

  w_need_reset();			/* controller gone deaf */
  return(0);
}

/*===========================================================================*
 *				w_geometry				     *
 *===========================================================================*/
PRIVATE void w_geometry(entry)
struct partition *entry;
{
  struct wini *wn = w_wn;

  if (wn->state & ATAPI) {		/* Make up some numbers. */
	entry->cylinders = div64u(wn->part[0].dv_size, SECTOR_SIZE) / (64*32);
	entry->heads = 64;
	entry->sectors = 32;
  } else {				/* Return logical geometry. */
	entry->cylinders = wn->lcylinders;
	entry->heads = wn->lheads;
	entry->sectors = wn->lsectors;
  }
}

#if ENABLE_ATAPI
/*===========================================================================*
 *				atapi_open				     *
 *===========================================================================*/
PRIVATE int atapi_open()
{
/* Should load and lock the device and obtain its size.  For now just set the
 * size of the device to something big.  What is really needed is a generic
 * SCSI layer that does all this stuff for ATAPI and SCSI devices (kjb). (XXX)
 */
  w_wn->part[0].dv_size = mul64u(800L*1024, 1024);
  return(OK);
}

/*===========================================================================*
 *				atapi_close				     *
 *===========================================================================*/
PRIVATE void atapi_close()
{
/* Should unlock the device.  For now do nothing.  (XXX) */
}

void sense_request(void)
{
	int r, i;
	static u8_t sense[100], packet[ATAPI_PACKETSIZE];

	packet[0] = SCSI_SENSE;
	packet[1] = 0;
	packet[2] = 0;
	packet[3] = 0;
	packet[4] = SENSE_PACKETSIZE;
	packet[5] = 0;
	packet[7] = 0;
	packet[8] = 0;
	packet[9] = 0;
	packet[10] = 0;
	packet[11] = 0;