sym53c8xx.c

uboot详细解读可用启动引导LINUX2.6内核

/*
 * (C) Copyright 2001
 * Denis Peter, MPL AG Switzerland, [e-mail].
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program 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 of
 * the License, or (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 * partly derived from
 * linux/drivers/scsi/sym53c8xx.c
 *
 */

/*
 * SCSI support based on the chip sym53C810.
 *
 * 09-19-2001 Andreas Heppel, Sysgo RTS GmbH <[e-mail]>
 *		The local version of this driver for the BAB750 board does not
 *		use interrupts but polls the chip instead (see the call of
 *		'handle_scsi_int()' in 'scsi_issue()'.
 */

#include <common.h>

#ifdef CONFIG_SCSI_SYM53C8XX

#include <command.h>
#include <pci.h>
#include <asm/processor.h>
#include <sym53c8xx.h>
#include <scsi.h>

#undef	SYM53C8XX_DEBUG

#ifdef	SYM53C8XX_DEBUG
#define	PRINTF(fmt,args...)	printf (fmt ,##args)
#else
#define PRINTF(fmt,args...)
#endif

#if defined(CONFIG_CMD_SCSI) && defined(CONFIG_SCSI_SYM53C8XX)

#undef SCSI_SINGLE_STEP
/*
 * Single Step is only used for debug purposes
 */
#ifdef SCSI_SINGLE_STEP
static unsigned long start_script_select;
static unsigned long start_script_msgout;
static unsigned long start_script_msgin;
static unsigned long start_script_msg_ext;
static unsigned long start_script_cmd;
static unsigned long start_script_data_in;
static unsigned long start_script_data_out;
static unsigned long start_script_status;
static unsigned long start_script_complete;
static unsigned long start_script_error;
static unsigned long start_script_reselection;
static unsigned int len_script_select;
static unsigned int len_script_msgout;
static unsigned int len_script_msgin;
static unsigned int len_script_msg_ext;
static unsigned int len_script_cmd;
static unsigned int len_script_data_in;
static unsigned int len_script_data_out;
static unsigned int len_script_status;
static unsigned int len_script_complete;
static unsigned int len_script_error;
static unsigned int len_script_reselection;
#endif


static unsigned short scsi_int_mask;	/* shadow register for SCSI related interrupts */
static unsigned char  script_int_mask;	/* shadow register for SCRIPT related interrupts */
static unsigned long script_select[8];	/* script for selection */
static unsigned long script_msgout[8];	/* script for message out phase (NOT USED) */
static unsigned long script_msgin[14];	/* script for message in phase */
static unsigned long script_msg_ext[32]; /* script for message in phase when more than 1 byte message */
static unsigned long script_cmd[18];    /* script for command phase */
static unsigned long script_data_in[8]; /* script for data in phase */
static unsigned long script_data_out[8]; /* script for data out phase */
static unsigned long script_status[6]; /* script for status phase */
static unsigned long script_complete[10]; /* script for complete */
static unsigned long script_reselection[4]; /* script for reselection (NOT USED) */
static unsigned long script_error[2]; /* script for error handling */

static unsigned long int_stat[3]; /* interrupt status */
static unsigned long scsi_mem_addr; /* base memory address =SCSI_MEM_ADDRESS; */

#define bus_to_phys(a)	pci_mem_to_phys(busdevfunc, (unsigned long) (a))
#define phys_to_bus(a)	pci_phys_to_mem(busdevfunc, (unsigned long) (a))

#define SCSI_MAX_RETRY 3 /* number of retries in scsi_issue() */

#define SCSI_MAX_RETRY_NOT_READY 10 /* number of retries when device is not ready */
#define SCSI_NOT_READY_TIME_OUT 500 /* timeout per retry when not ready */

/*********************************************************************************
 * forward declerations
 */

void scsi_chip_init(void);
void handle_scsi_int(void);


/********************************************************************************
 * reports SCSI errors to the user
 */
void scsi_print_error (ccb * pccb)
{
	int i;

	printf ("SCSI Error: Target %d LUN %d Command %02X\n", pccb->target,
		pccb->lun, pccb->cmd[0]);
	printf ("       CCB: ");
	for (i = 0; i < pccb->cmdlen; i++)
		printf ("%02X ", pccb->cmd[i]);
	printf ("(len=%d)\n", pccb->cmdlen);
	printf ("     Cntrl: ");
	switch (pccb->contr_stat) {
	case SIR_COMPLETE:
		printf ("Complete (no Error)\n");
		break;
	case SIR_SEL_ATN_NO_MSG_OUT:
		printf ("Selected with ATN no MSG out phase\n");
		break;
	case SIR_CMD_OUT_ILL_PH:
		printf ("Command out illegal phase\n");
		break;
	case SIR_MSG_RECEIVED:
		printf ("MSG received Error\n");
		break;
	case SIR_DATA_IN_ERR:
		printf ("Data in Error\n");
		break;
	case SIR_DATA_OUT_ERR:
		printf ("Data out Error\n");
		break;
	case SIR_SCRIPT_ERROR:
		printf ("Script Error\n");
		break;
	case SIR_MSG_OUT_NO_CMD:
		printf ("MSG out no Command phase\n");
		break;
	case SIR_MSG_OVER7:
		printf ("MSG in over 7 bytes\n");
		break;
	case INT_ON_FY:
		printf ("Interrupt on fly\n");
		break;
	case SCSI_SEL_TIME_OUT:
		printf ("SCSI Selection Timeout\n");
		break;
	case SCSI_HNS_TIME_OUT:
		printf ("SCSI Handshake Timeout\n");
		break;
	case SCSI_MA_TIME_OUT:
		printf ("SCSI Phase Error\n");
		break;
	case SCSI_UNEXP_DIS:
		printf ("SCSI unexpected disconnect\n");
		break;
	default:
		printf ("unknown status %lx\n", pccb->contr_stat);
		break;
	}
	printf ("     Sense: SK %x (", pccb->sense_buf[2] & 0x0f);
	switch (pccb->sense_buf[2] & 0xf) {
	case SENSE_NO_SENSE:
		printf ("No Sense)");
		break;
	case SENSE_RECOVERED_ERROR:
		printf ("Recovered Error)");
		break;
	case SENSE_NOT_READY:
		printf ("Not Ready)");
		break;
	case SENSE_MEDIUM_ERROR:
		printf ("Medium Error)");
		break;
	case SENSE_HARDWARE_ERROR:
		printf ("Hardware Error)");
		break;
	case SENSE_ILLEGAL_REQUEST:
		printf ("Illegal request)");
		break;
	case SENSE_UNIT_ATTENTION:
		printf ("Unit Attention)");
		break;
	case SENSE_DATA_PROTECT:
		printf ("Data Protect)");
		break;
	case SENSE_BLANK_CHECK:
		printf ("Blank check)");
		break;
	case SENSE_VENDOR_SPECIFIC:
		printf ("Vendor specific)");
		break;
	case SENSE_COPY_ABORTED:
		printf ("Copy aborted)");
		break;
	case SENSE_ABORTED_COMMAND:
		printf ("Aborted Command)");
		break;
	case SENSE_VOLUME_OVERFLOW:
		printf ("Volume overflow)");
		break;
	case SENSE_MISCOMPARE:
		printf ("Misscompare\n");
		break;
	default:
		printf ("Illegal Sensecode\n");
		break;
	}
	printf (" ASC %x ASCQ %x\n", pccb->sense_buf[12],
		pccb->sense_buf[13]);
	printf ("    Status: ");
	switch (pccb->status) {
	case S_GOOD:
		printf ("Good\n");
		break;
	case S_CHECK_COND:
		printf ("Check condition\n");
		break;
	case S_COND_MET:
		printf ("Condition Met\n");
		break;
	case S_BUSY:
		printf ("Busy\n");
		break;
	case S_INT:
		printf ("Intermediate\n");
		break;
	case S_INT_COND_MET:
		printf ("Intermediate condition met\n");
		break;
	case S_CONFLICT:
		printf ("Reservation conflict\n");
		break;
	case S_TERMINATED:
		printf ("Command terminated\n");
		break;
	case S_QUEUE_FULL:
		printf ("Task set full\n");
		break;
	default:
		printf ("unknown: %02X\n", pccb->status);
		break;
	}

}


/******************************************************************************
 * sets-up the SCSI controller
 * the base memory address is retrived via the pci_read_config_dword
 */
void scsi_low_level_init(int busdevfunc)
{
	unsigned int cmd;
	unsigned int addr;
	unsigned char vec;

	pci_read_config_byte(busdevfunc, PCI_INTERRUPT_LINE, &vec);
	pci_read_config_dword(busdevfunc, PCI_BASE_ADDRESS_1, &addr);

	addr = bus_to_phys(addr & ~0xf);

	/*
	 * Enable bus mastering in case this has not been done, yet.
	 */
	pci_read_config_dword(busdevfunc, PCI_COMMAND, &cmd);
	cmd |= PCI_COMMAND_MASTER;
	pci_write_config_dword(busdevfunc, PCI_COMMAND, cmd);

	scsi_mem_addr = addr;

	scsi_chip_init();
	scsi_bus_reset();
}


/************************************************************************************
 * Low level Part of SCSI Driver
 */

/*
 * big-endian -> little endian conversion for the script
 */
unsigned long swap_script(unsigned long val)
{
	unsigned long tmp;
	tmp = ((val>>24)&0xff) | ((val>>8)&0xff00) | ((val<<8)&0xff0000) | ((val<<24)&0xff000000);
	return tmp;
}


void scsi_write_byte(ulong offset,unsigned char val)
{
	out8(scsi_mem_addr+offset,val);
}


unsigned char scsi_read_byte(ulong offset)
{
	return(in8(scsi_mem_addr+offset));
}


/********************************************************************************
 * interrupt handler
 */
void handle_scsi_int(void)
{
	unsigned char stat,stat1,stat2;
	unsigned short sstat;
	int i;
#ifdef SCSI_SINGLE_STEP
	unsigned long tt;
#endif
	stat=scsi_read_byte(ISTAT);
	if((stat & DIP)==DIP) { /* DMA Interrupt pending */
		stat1=scsi_read_byte(DSTAT);
#ifdef SCSI_SINGLE_STEP
		if((stat1 & SSI)==SSI) {
			tt=in32r(scsi_mem_addr+DSP);
			if(((tt)>=start_script_select) && ((tt)<start_script_select+len_script_select)) {
				printf("select %d\n",(tt-start_script_select)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_msgout) && ((tt)<start_script_msgout+len_script_msgout)) {
				printf("msgout %d\n",(tt-start_script_msgout)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_msgin) && ((tt)<start_script_msgin+len_script_msgin)) {
				printf("msgin %d\n",(tt-start_script_msgin)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_msg_ext) && ((tt)<start_script_msg_ext+len_script_msg_ext)) {
				printf("msgin_ext %d\n",(tt-start_script_msg_ext)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_cmd) && ((tt)<start_script_cmd+len_script_cmd)) {
				printf("cmd %d\n",(tt-start_script_cmd)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_data_in) && ((tt)<start_script_data_in+len_script_data_in)) {
				printf("data_in %d\n",(tt-start_script_data_in)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_data_out) && ((tt)<start_script_data_out+len_script_data_out)) {
				printf("data_out %d\n",(tt-start_script_data_out)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_status) && ((tt)<start_script_status+len_script_status)) {
				printf("status %d\n",(tt-start_script_status)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_complete) && ((tt)<start_script_complete+len_script_complete)) {
				printf("complete %d\n",(tt-start_script_complete)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_error) && ((tt)<start_script_error+len_script_error)) {
				printf("error %d\n",(tt-start_script_error)>>2);
				goto end_single;
			}
			if(((tt)>=start_script_reselection) && ((tt)<start_script_reselection+len_script_reselection)) {
				printf("reselection %d\n",(tt-start_script_reselection)>>2);
				goto end_single;
			}
			printf("sc: %lx\n",tt);
end_single:
			stat2=scsi_read_byte(DCNTL);
			stat2|=STD;
			scsi_write_byte(DCNTL,stat2);
		}
#endif
		if((stat1 & SIR)==SIR) /* script interrupt */
		{
			int_stat[0]=in32(scsi_mem_addr+DSPS);
		}
		if((stat1 & DFE)==0) { /* fifo not epmty */
			scsi_write_byte(CTEST3,CLF); /* Clear DMA FIFO */
			stat2=scsi_read_byte(STEST3);
			scsi_write_byte(STEST3,(stat2 | CSF)); /* Clear SCSI FIFO */
		}
	}
	if((stat & SIP)==SIP) {  /* scsi interrupt */
		sstat = (unsigned short)scsi_read_byte(SIST+1);
		sstat <<=8;
		sstat |= (unsigned short)scsi_read_byte(SIST);
		for(i=0;i<3;i++) {
			if(int_stat[i]==0)
				break; /* found an empty int status */
		}
		int_stat[i]=SCSI_INT_STATE | sstat;
		stat1=scsi_read_byte(DSTAT);
		if((stat1 & DFE)==0) { /* fifo not epmty */
			scsi_write_byte(CTEST3,CLF); /* Clear DMA FIFO */
			stat2=scsi_read_byte(STEST3);
			scsi_write_byte(STEST3,(stat2 | CSF)); /* Clear SCSI FIFO */
		}
	}
	if((stat & INTF)==INTF) { /* interrupt on Fly */
		scsi_write_byte(ISTAT,stat); /* clear it */
		for(i=0;i<3;i++) {
			if(int_stat[i]==0)
				break; /* found an empty int status */
		}
		int_stat[i]=INT_ON_FY;
	}
}

void scsi_bus_reset(void)
{
	unsigned char t;
	int i;
	int end = CFG_SCSI_SPIN_UP_TIME*1000;

	t=scsi_read_byte(SCNTL1);
	scsi_write_byte(SCNTL1,(t | CRST));
	udelay(50);
	scsi_write_byte(SCNTL1,t);

	puts("waiting for devices to spin up");