cmd/scsi.c

/*
 * (C) Copyright 2001
 * Denis Peter, MPL AG Switzerland
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * SCSI support.
 */
#include <common.h>
#include <command.h>
#include <inttypes.h>
#include <asm/processor.h>
#include <scsi.h>
#include <image.h>
#include <pci.h>

#ifdef CONFIG_SCSI_DEV_LIST
#define SCSI_DEV_LIST CONFIG_SCSI_DEV_LIST
#else
#ifdef CONFIG_SCSI_SYM53C8XX
#define SCSI_VEND_ID	0x1000
#ifndef CONFIG_SCSI_DEV_ID
#define SCSI_DEV_ID		0x0001
#else
#define SCSI_DEV_ID		CONFIG_SCSI_DEV_ID
#endif
#elif defined CONFIG_SATA_ULI5288

#define SCSI_VEND_ID 0x10b9
#define SCSI_DEV_ID  0x5288

#elif !defined(CONFIG_SCSI_AHCI_PLAT)
#error no scsi device defined
#endif
#define SCSI_DEV_LIST {SCSI_VEND_ID, SCSI_DEV_ID}
#endif

#if defined(CONFIG_PCI) && !defined(CONFIG_SCSI_AHCI_PLAT)
const struct pci_device_id scsi_device_list[] = { SCSI_DEV_LIST };
#endif
static ccb tempccb;	/* temporary scsi command buffer */

static unsigned char tempbuff[512]; /* temporary data buffer */

static int scsi_max_devs; /* number of highest available scsi device */

static int scsi_curr_dev; /* current device */

static struct blk_desc scsi_dev_desc[CONFIG_SYS_SCSI_MAX_DEVICE];

/* almost the maximum amount of the scsi_ext command.. */
#define SCSI_MAX_READ_BLK 0xFFFF
#define SCSI_LBA48_READ	0xFFFFFFF

#ifdef CONFIG_SYS_64BIT_LBA
void scsi_setup_read16(ccb *pccb, lbaint_t start, unsigned long blocks)
{
	pccb->cmd[0] = SCSI_READ16;
	pccb->cmd[1] = pccb->lun << 5;
	pccb->cmd[2] = (unsigned char)(start >> 56) & 0xff;
	pccb->cmd[3] = (unsigned char)(start >> 48) & 0xff;
	pccb->cmd[4] = (unsigned char)(start >> 40) & 0xff;
	pccb->cmd[5] = (unsigned char)(start >> 32) & 0xff;
	pccb->cmd[6] = (unsigned char)(start >> 24) & 0xff;
	pccb->cmd[7] = (unsigned char)(start >> 16) & 0xff;
	pccb->cmd[8] = (unsigned char)(start >> 8) & 0xff;
	pccb->cmd[9] = (unsigned char)start & 0xff;
	pccb->cmd[10] = 0;
	pccb->cmd[11] = (unsigned char)(blocks >> 24) & 0xff;
	pccb->cmd[12] = (unsigned char)(blocks >> 16) & 0xff;
	pccb->cmd[13] = (unsigned char)(blocks >> 8) & 0xff;
	pccb->cmd[14] = (unsigned char)blocks & 0xff;
	pccb->cmd[15] = 0;
	pccb->cmdlen = 16;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */
	debug("scsi_setup_read16: cmd: %02X %02X startblk %02X%02X%02X%02X%02X%02X%02X%02X blccnt %02X%02X%02X%02X\n",
	      pccb->cmd[0], pccb->cmd[1],
	      pccb->cmd[2], pccb->cmd[3], pccb->cmd[4], pccb->cmd[5],
	      pccb->cmd[6], pccb->cmd[7], pccb->cmd[8], pccb->cmd[9],
	      pccb->cmd[11], pccb->cmd[12], pccb->cmd[13], pccb->cmd[14]);
}
#endif

void scsi_setup_read_ext(ccb * pccb, lbaint_t start, unsigned short blocks)
{
	pccb->cmd[0] = SCSI_READ10;
	pccb->cmd[1] = pccb->lun << 5;
	pccb->cmd[2] = (unsigned char)(start >> 24) & 0xff;
	pccb->cmd[3] = (unsigned char)(start >> 16) & 0xff;
	pccb->cmd[4] = (unsigned char)(start >> 8) & 0xff;
	pccb->cmd[5] = (unsigned char)start & 0xff;
	pccb->cmd[6] = 0;
	pccb->cmd[7] = (unsigned char)(blocks >> 8) & 0xff;
	pccb->cmd[8] = (unsigned char)blocks & 0xff;
	pccb->cmd[6] = 0;
	pccb->cmdlen=10;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */
	debug ("scsi_setup_read_ext: cmd: %02X %02X startblk %02X%02X%02X%02X blccnt %02X%02X\n",
		pccb->cmd[0],pccb->cmd[1],
		pccb->cmd[2],pccb->cmd[3],pccb->cmd[4],pccb->cmd[5],
		pccb->cmd[7],pccb->cmd[8]);
}

void scsi_setup_write_ext(ccb *pccb, lbaint_t start, unsigned short blocks)
{
	pccb->cmd[0] = SCSI_WRITE10;
	pccb->cmd[1] = pccb->lun << 5;
	pccb->cmd[2] = (unsigned char)(start >> 24) & 0xff;
	pccb->cmd[3] = (unsigned char)(start >> 16) & 0xff;
	pccb->cmd[4] = (unsigned char)(start >> 8) & 0xff;
	pccb->cmd[5] = (unsigned char)start & 0xff;
	pccb->cmd[6] = 0;
	pccb->cmd[7] = ((unsigned char)(blocks >> 8)) & 0xff;
	pccb->cmd[8] = (unsigned char)blocks & 0xff;
	pccb->cmd[9] = 0;
	pccb->cmdlen = 10;
	pccb->msgout[0] = SCSI_IDENTIFY;  /* NOT USED */
	debug("%s: cmd: %02X %02X startblk %02X%02X%02X%02X blccnt %02X%02X\n",
	      __func__,
	      pccb->cmd[0], pccb->cmd[1],
	      pccb->cmd[2], pccb->cmd[3], pccb->cmd[4], pccb->cmd[5],
	      pccb->cmd[7], pccb->cmd[8]);
}

void scsi_setup_read6(ccb * pccb, lbaint_t start, unsigned short blocks)
{
	pccb->cmd[0] = SCSI_READ6;
	pccb->cmd[1] = pccb->lun << 5 | ((unsigned char)(start >> 16) & 0x1f);
	pccb->cmd[2] = (unsigned char)(start >> 8) & 0xff;
	pccb->cmd[3] = (unsigned char)start & 0xff;
	pccb->cmd[4] = (unsigned char)blocks & 0xff;
	pccb->cmd[5] = 0;
	pccb->cmdlen=6;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */
	debug("scsi_setup_read6: cmd: %02X %02X startblk %02X%02X blccnt %02X\n",
	      pccb->cmd[0], pccb->cmd[1],
	      pccb->cmd[2], pccb->cmd[3], pccb->cmd[4]);
}


void scsi_setup_inquiry(ccb * pccb)
{
	pccb->cmd[0] = SCSI_INQUIRY;
	pccb->cmd[1] = pccb->lun << 5;
	pccb->cmd[2] = 0;
	pccb->cmd[3] = 0;
	if (pccb->datalen > 255)
		pccb->cmd[4] = 255;
	else
		pccb->cmd[4] = (unsigned char)pccb->datalen;
	pccb->cmd[5] = 0;
	pccb->cmdlen=6;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */
}

static ulong scsi_read(struct blk_desc *block_dev, lbaint_t blknr,
		       lbaint_t blkcnt, void *buffer)
{
	int device = block_dev->devnum;
	lbaint_t start, blks;
	uintptr_t buf_addr;
	unsigned short smallblks = 0;
	ccb* pccb=(ccb *)&tempccb;
	device&=0xff;

	/* Setup device */
	pccb->target = scsi_dev_desc[device].target;
	pccb->lun = scsi_dev_desc[device].lun;
	buf_addr = (unsigned long)buffer;
	start = blknr;
	blks = blkcnt;
	debug("\nscsi_read: dev %d startblk " LBAF
	      ", blccnt " LBAF " buffer %lx\n",
	      device, start, blks, (unsigned long)buffer);
	do {
		pccb->pdata = (unsigned char *)buf_addr;
#ifdef CONFIG_SYS_64BIT_LBA
		if (start > SCSI_LBA48_READ) {
			unsigned long blocks;
			blocks = min_t(lbaint_t, blks, SCSI_MAX_READ_BLK);
			pccb->datalen = scsi_dev_desc[device].blksz * blocks;
			scsi_setup_read16(pccb, start, blocks);
			start += blocks;
			blks -= blocks;
		} else
#endif
		if (blks > SCSI_MAX_READ_BLK) {
			pccb->datalen = scsi_dev_desc[device].blksz *
				SCSI_MAX_READ_BLK;
			smallblks = SCSI_MAX_READ_BLK;
			scsi_setup_read_ext(pccb, start, smallblks);
			start += SCSI_MAX_READ_BLK;
			blks -= SCSI_MAX_READ_BLK;
		}
		else {
			pccb->datalen = scsi_dev_desc[device].blksz * blks;
			smallblks = (unsigned short)blks;
			scsi_setup_read_ext(pccb, start, smallblks);
			start += blks;
			blks=0;
		}
		debug("scsi_read_ext: startblk " LBAF
		      ", blccnt %x buffer %" PRIXPTR "\n",
		      start, smallblks, buf_addr);
		if (scsi_exec(pccb) != true) {
			scsi_print_error(pccb);
			blkcnt -= blks;
			break;
		}
		buf_addr+=pccb->datalen;
	} while (blks != 0);
	debug("scsi_read_ext: end startblk " LBAF
	      ", blccnt %x buffer %" PRIXPTR "\n", start, smallblks, buf_addr);
	return blkcnt;
}

/*******************************************************************************
 * scsi_write
 */

/* Almost the maximum amount of the scsi_ext command.. */
#define SCSI_MAX_WRITE_BLK 0xFFFF

static ulong scsi_write(struct blk_desc *block_dev, lbaint_t blknr,
			lbaint_t blkcnt, const void *buffer)
{
	int device = block_dev->devnum;
	lbaint_t start, blks;
	uintptr_t buf_addr;
	unsigned short smallblks;
	ccb* pccb = (ccb *)&tempccb;
	device &= 0xff;
	/* Setup  device
	 */
	pccb->target = scsi_dev_desc[device].target;
	pccb->lun = scsi_dev_desc[device].lun;
	buf_addr = (unsigned long)buffer;
	start = blknr;
	blks = blkcnt;
	debug("\n%s: dev %d startblk " LBAF ", blccnt " LBAF " buffer %lx\n",
	      __func__, device, start, blks, (unsigned long)buffer);
	do {
		pccb->pdata = (unsigned char *)buf_addr;
		if (blks > SCSI_MAX_WRITE_BLK) {
			pccb->datalen = (scsi_dev_desc[device].blksz *
					 SCSI_MAX_WRITE_BLK);
			smallblks = SCSI_MAX_WRITE_BLK;
			scsi_setup_write_ext(pccb, start, smallblks);
			start += SCSI_MAX_WRITE_BLK;
			blks -= SCSI_MAX_WRITE_BLK;
		} else {
			pccb->datalen = scsi_dev_desc[device].blksz * blks;
			smallblks = (unsigned short)blks;
			scsi_setup_write_ext(pccb, start, smallblks);
			start += blks;
			blks = 0;
		}
		debug("%s: startblk " LBAF ", blccnt %x buffer %" PRIXPTR "\n",
		      __func__, start, smallblks, buf_addr);
		if (scsi_exec(pccb) != true) {
			scsi_print_error(pccb);
			blkcnt -= blks;
			break;
		}
		buf_addr += pccb->datalen;
	} while (blks != 0);
	debug("%s: end startblk " LBAF ", blccnt %x buffer %" PRIXPTR "\n",
	      __func__, start, smallblks, buf_addr);
	return blkcnt;
}

int scsi_get_disk_count(void)
{
	return scsi_max_devs;
}

#if defined(CONFIG_PCI) && !defined(CONFIG_SCSI_AHCI_PLAT)
void scsi_init(void)
{
	int busdevfunc = -1;
	int i;
	/*
	 * Find a device from the list, this driver will support a single
	 * controller.
	 */
	for (i = 0; i < ARRAY_SIZE(scsi_device_list); i++) {
		/* get PCI Device ID */
#ifdef CONFIG_DM_PCI
		struct udevice *dev;
		int ret;

		ret = dm_pci_find_device(scsi_device_list[i].vendor,
					 scsi_device_list[i].device, 0, &dev);
		if (!ret) {
			busdevfunc = dm_pci_get_bdf(dev);
			break;
		}
#else
		busdevfunc = pci_find_device(scsi_device_list[i].vendor,
					     scsi_device_list[i].device,
					     0);
#endif
		if (busdevfunc != -1)
			break;
	}

	if (busdevfunc == -1) {
		printf("Error: SCSI Controller(s) ");
		for (i = 0; i < ARRAY_SIZE(scsi_device_list); i++) {
			printf("%04X:%04X ",
			       scsi_device_list[i].vendor,
			       scsi_device_list[i].device);
		}
		printf("not found\n");
		return;
	}
#ifdef DEBUG
	else {
		printf("SCSI Controller (%04X,%04X) found (%d:%d:%d)\n",
		       scsi_device_list[i].vendor,
		       scsi_device_list[i].device,
		       (busdevfunc >> 16) & 0xFF,
		       (busdevfunc >> 11) & 0x1F,
		       (busdevfunc >> 8) & 0x7);
	}
#endif
	bootstage_start(BOOTSTAGE_ID_ACCUM_SCSI, "ahci");
	scsi_low_level_init(busdevfunc);
	scsi_scan(1);
	bootstage_accum(BOOTSTAGE_ID_ACCUM_SCSI);
}
#endif

#ifdef CONFIG_PARTITIONS
struct blk_desc *scsi_get_dev(int dev)
{
	return (dev < CONFIG_SYS_SCSI_MAX_DEVICE) ? &scsi_dev_desc[dev] : NULL;
}
#endif

#ifndef CONFIG_SPL_BUILD
/******************************************************************************
 * scsi boot command intepreter. Derived from diskboot
 */
int do_scsiboot (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	return common_diskboot(cmdtp, "scsi", argc, argv);
}

/*********************************************************************************
 * scsi command intepreter
 */
int do_scsi (cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	switch (argc) {
	case 0:
	case 1:
		return CMD_RET_USAGE;

	case 2:
		if (strncmp(argv[1], "res", 3) == 0) {
			printf("\nReset SCSI\n");
			scsi_bus_reset();
			scsi_scan(1);
			return 0;
		}
		if (strncmp(argv[1], "inf", 3) == 0) {
			int i;
			for (i = 0; i < CONFIG_SYS_SCSI_MAX_DEVICE; ++i) {
				if (scsi_dev_desc[i].type == DEV_TYPE_UNKNOWN)
					continue; /* list only known devices */
				printf("SCSI dev. %d:  ", i);
				dev_print(&scsi_dev_desc[i]);
			}
			return 0;
		}
		if (strncmp(argv[1], "dev", 3) == 0) {
			if (scsi_curr_dev < 0 ||
			    scsi_curr_dev >= CONFIG_SYS_SCSI_MAX_DEVICE) {
				printf("\nno SCSI devices available\n");
				return 1;
			}
			printf("\n    Device %d: ", scsi_curr_dev);
			dev_print(&scsi_dev_desc[scsi_curr_dev]);
			return 0;
		}
		if (strncmp(argv[1], "scan", 4) == 0) {
			scsi_scan(1);
			return 0;
		}
		if (strncmp(argv[1], "part", 4) == 0) {
			int dev, ok;
			for (ok = 0, dev = 0;
			     dev < CONFIG_SYS_SCSI_MAX_DEVICE; ++dev) {
				if (scsi_dev_desc[dev].type !=
				    DEV_TYPE_UNKNOWN) {
					ok++;
					if (dev)
						printf("\n");
					debug("print_part of %x\n", dev);
					part_print(&scsi_dev_desc[dev]);
				}
			}
			if (!ok)
				printf("\nno SCSI devices available\n");
			return 1;
		}
		return CMD_RET_USAGE;
	case 3:
		if (strncmp(argv[1], "dev", 3) == 0) {
			int dev = (int)simple_strtoul(argv[2], NULL, 10);
			printf("\nSCSI device %d: ", dev);
			if (dev >= CONFIG_SYS_SCSI_MAX_DEVICE) {
				printf("unknown device\n");
				return 1;
			}
			printf("\n    Device %d: ", dev);
			dev_print(&scsi_dev_desc[dev]);
			if (scsi_dev_desc[dev].type == DEV_TYPE_UNKNOWN)
				return 1;
			scsi_curr_dev = dev;
			printf("... is now current device\n");
			return 0;
		}
		if (strncmp(argv[1], "part", 4) == 0) {
			int dev = (int)simple_strtoul(argv[2], NULL, 10);
			if (scsi_dev_desc[dev].type != DEV_TYPE_UNKNOWN)
				part_print(&scsi_dev_desc[dev]);
			else
				printf("\nSCSI device %d not available\n", dev);
			return 1;
		}
		return CMD_RET_USAGE;
	default:
		/* at least 4 args */
		if (strcmp(argv[1], "read") == 0) {
			ulong addr = simple_strtoul(argv[2], NULL, 16);
			ulong blk  = simple_strtoul(argv[3], NULL, 16);
			ulong cnt  = simple_strtoul(argv[4], NULL, 16);
			ulong n;
			printf("\nSCSI read: device %d block # %ld, count %ld ... ",
			       scsi_curr_dev, blk, cnt);
			n = scsi_read(&scsi_dev_desc[scsi_curr_dev],
				      blk, cnt, (ulong *)addr);
			printf("%ld blocks read: %s\n", n,
			       n == cnt ? "OK" : "ERROR");
			return 0;
		} else if (strcmp(argv[1], "write") == 0) {
			ulong addr = simple_strtoul(argv[2], NULL, 16);
			ulong blk = simple_strtoul(argv[3], NULL, 16);
			ulong cnt = simple_strtoul(argv[4], NULL, 16);
			ulong n;
			printf("\nSCSI write: device %d block # %ld, count %ld ... ",
			       scsi_curr_dev, blk, cnt);
			n = scsi_write(&scsi_dev_desc[scsi_curr_dev],
				       blk, cnt, (ulong *)addr);
			printf("%ld blocks written: %s\n", n,
			       n == cnt ? "OK" : "ERROR");
			return 0;
		}
	} /* switch */
	return CMD_RET_USAGE;
}

U_BOOT_CMD(
	scsi, 5, 1, do_scsi,
	"SCSI sub-system",
	"reset - reset SCSI controller\n"
	"scsi info  - show available SCSI devices\n"
	"scsi scan  - (re-)scan SCSI bus\n"
	"scsi device [dev] - show or set current device\n"
	"scsi part [dev] - print partition table of one or all SCSI devices\n"
	"scsi read addr blk# cnt - read `cnt' blocks starting at block `blk#'\n"
	"     to memory address `addr'\n"
	"scsi write addr blk# cnt - write `cnt' blocks starting at block\n"
	"     `blk#' from memory address `addr'"
);

U_BOOT_CMD(
	scsiboot, 3, 1, do_scsiboot,
	"boot from SCSI device",
	"loadAddr dev:part"
);
#endif

/* copy src to dest, skipping leading and trailing blanks
 * and null terminate the string
 */
void scsi_ident_cpy(unsigned char *dest, unsigned char *src, unsigned int len)
{
	int start,end;

	start = 0;
	while (start < len) {
		if (src[start] != ' ')
			break;
		start++;
	}
	end = len-1;
	while (end > start) {
		if (src[end] != ' ')
			break;
		end--;
	}
	for (; start <= end; start++)
		*dest ++= src[start];
	*dest='\0';
}


/* Trim trailing blanks, and NUL-terminate string
 */
void scsi_trim_trail (unsigned char *str, unsigned int len)
{
	unsigned char *p = str + len - 1;

	while (len-- > 0) {
		*p-- = '\0';
		if (*p != ' ') {
			return;
		}
	}
}

int scsi_read_capacity(ccb *pccb, lbaint_t *capacity, unsigned long *blksz)
{
	*capacity = 0;

	memset(pccb->cmd, '\0', sizeof(pccb->cmd));
	pccb->cmd[0] = SCSI_RD_CAPAC10;
	pccb->cmd[1] = pccb->lun << 5;
	pccb->cmdlen = 10;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */

	pccb->datalen = 8;
	if (scsi_exec(pccb) != true)
		return 1;

	*capacity = ((lbaint_t)pccb->pdata[0] << 24) |
		    ((lbaint_t)pccb->pdata[1] << 16) |
		    ((lbaint_t)pccb->pdata[2] << 8)  |
		    ((lbaint_t)pccb->pdata[3]);

	if (*capacity != 0xffffffff) {
		/* Read capacity (10) was sufficient for this drive. */
		*blksz = ((unsigned long)pccb->pdata[4] << 24) |
			 ((unsigned long)pccb->pdata[5] << 16) |
			 ((unsigned long)pccb->pdata[6] << 8)  |
			 ((unsigned long)pccb->pdata[7]);
		return 0;
	}

	/* Read capacity (10) was insufficient. Use read capacity (16). */
	memset(pccb->cmd, '\0', sizeof(pccb->cmd));
	pccb->cmd[0] = SCSI_RD_CAPAC16;
	pccb->cmd[1] = 0x10;
	pccb->cmdlen = 16;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */

	pccb->datalen = 16;
	if (scsi_exec(pccb) != true)
		return 1;

	*capacity = ((uint64_t)pccb->pdata[0] << 56) |
		    ((uint64_t)pccb->pdata[1] << 48) |
		    ((uint64_t)pccb->pdata[2] << 40) |
		    ((uint64_t)pccb->pdata[3] << 32) |
		    ((uint64_t)pccb->pdata[4] << 24) |
		    ((uint64_t)pccb->pdata[5] << 16) |
		    ((uint64_t)pccb->pdata[6] << 8)  |
		    ((uint64_t)pccb->pdata[7]);

	*blksz = ((uint64_t)pccb->pdata[8]  << 56) |
		 ((uint64_t)pccb->pdata[9]  << 48) |
		 ((uint64_t)pccb->pdata[10] << 40) |
		 ((uint64_t)pccb->pdata[11] << 32) |
		 ((uint64_t)pccb->pdata[12] << 24) |
		 ((uint64_t)pccb->pdata[13] << 16) |
		 ((uint64_t)pccb->pdata[14] << 8)  |
		 ((uint64_t)pccb->pdata[15]);

	return 0;
}


/************************************************************************************
 * Some setup (fill-in) routines
 */
void scsi_setup_test_unit_ready(ccb * pccb)
{
	pccb->cmd[0] = SCSI_TST_U_RDY;
	pccb->cmd[1] = pccb->lun << 5;
	pccb->cmd[2] = 0;
	pccb->cmd[3] = 0;
	pccb->cmd[4] = 0;
	pccb->cmd[5] = 0;
	pccb->cmdlen = 6;
	pccb->msgout[0] = SCSI_IDENTIFY; /* NOT USED */
}

/*********************************************************************************
 * (re)-scan the scsi bus and reports scsi device info
 * to the user if mode = 1
 */
void scsi_scan(int mode)
{
	unsigned char i,perq,modi,lun;
	lbaint_t capacity;
	unsigned long blksz;
	ccb* pccb=(ccb *)&tempccb;

	if (mode == 1)
		printf("scanning bus for devices...\n");
	for (i = 0; i < CONFIG_SYS_SCSI_MAX_DEVICE; i++) {
		scsi_dev_desc[i].target = 0xff;
		scsi_dev_desc[i].lun = 0xff;
		scsi_dev_desc[i].lba = 0;
		scsi_dev_desc[i].blksz = 0;
		scsi_dev_desc[i].log2blksz  =
			LOG2_INVALID(typeof(scsi_dev_desc[i].log2blksz));
		scsi_dev_desc[i].type = DEV_TYPE_UNKNOWN;
		scsi_dev_desc[i].vendor[0] = 0;
		scsi_dev_desc[i].product[0] = 0;
		scsi_dev_desc[i].revision[0] = 0;
		scsi_dev_desc[i].removable = false;
		scsi_dev_desc[i].if_type = IF_TYPE_SCSI;
		scsi_dev_desc[i].devnum = i;
		scsi_dev_desc[i].part_type = PART_TYPE_UNKNOWN;
		scsi_dev_desc[i].block_read = scsi_read;
		scsi_dev_desc[i].block_write = scsi_write;
	}
	scsi_max_devs = 0;
	for (i = 0; i < CONFIG_SYS_SCSI_MAX_SCSI_ID; i++) {
		pccb->target = i;
		for (lun = 0; lun < CONFIG_SYS_SCSI_MAX_LUN; lun++) {
			pccb->lun = lun;
			pccb->pdata = (unsigned char *)&tempbuff;
			pccb->datalen = 512;
			scsi_setup_inquiry(pccb);
			if (scsi_exec(pccb) != true) {
				if(pccb->contr_stat==SCSI_SEL_TIME_OUT) {
					debug("Selection timeout ID %d\n",
					      pccb->target);
					continue; /* selection timeout => assuming no device present */
				}
				scsi_print_error(pccb);
				continue;
			}
			perq = tempbuff[0];
			modi = tempbuff[1];
			if ((perq & 0x1f) == 0x1f)
				continue; /* skip unknown devices */
			if ((modi & 0x80) == 0x80) /* drive is removable */
				scsi_dev_desc[scsi_max_devs].removable = true;
			/* get info for this device */
			scsi_ident_cpy((unsigned char *)&scsi_dev_desc[scsi_max_devs].vendor[0],
				       &tempbuff[8], 8);
			scsi_ident_cpy((unsigned char *)&scsi_dev_desc[scsi_max_devs].product[0],
				       &tempbuff[16], 16);
			scsi_ident_cpy((unsigned char *)&scsi_dev_desc[scsi_max_devs].revision[0],
				       &tempbuff[32], 4);
			scsi_dev_desc[scsi_max_devs].target = pccb->target;
			scsi_dev_desc[scsi_max_devs].lun = pccb->lun;

			pccb->datalen = 0;
			scsi_setup_test_unit_ready(pccb);
			if (scsi_exec(pccb) != true) {
				if (scsi_dev_desc[scsi_max_devs].removable) {
					scsi_dev_desc[scsi_max_devs].type =
							perq;
					goto removable;
				}
				scsi_print_error(pccb);
				continue;
			}
			if (scsi_read_capacity(pccb, &capacity, &blksz)) {
				scsi_print_error(pccb);
				continue;
			}
			scsi_dev_desc[scsi_max_devs].lba = capacity;
			scsi_dev_desc[scsi_max_devs].blksz = blksz;
			scsi_dev_desc[scsi_max_devs].log2blksz =
				LOG2(scsi_dev_desc[scsi_max_devs].blksz);
			scsi_dev_desc[scsi_max_devs].type = perq;
			part_init(&scsi_dev_desc[scsi_max_devs]);
removable:
			if(mode==1) {
				printf ("  Device %d: ", scsi_max_devs);
				dev_print(&scsi_dev_desc[scsi_max_devs]);
			} /* if mode */
			scsi_max_devs++;
		} /* next LUN */
	}
	if (scsi_max_devs > 0)
		scsi_curr_dev = 0;
	else
		scsi_curr_dev = -1;

	printf("Found %d device(s).\n", scsi_max_devs);
#ifndef CONFIG_SPL_BUILD
	setenv_ulong("scsidevs", scsi_max_devs);
#endif
}