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u-boot/common/scsi.c
Jean-Jacques Hiblot 4e27b9a584 dm: scsi: fix divide-by-0 error in scsi_scan() 
With DM_SCSI enabled, blk_create_devicef() is called with blkz = 0, leading
to a divide-by-0 exception.
scsi_detect_dev() can be used to get the required parameters (block size
and number of blocks) from the drive before calling blk_create_devicef().

Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2017-04-14 19:38:57 -06:00

695 lines
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/*
* (C) Copyright 2001
* Denis Peter, MPL AG Switzerland
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <inttypes.h>
#include <pci.h>
#include <scsi.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#if !defined(CONFIG_DM_SCSI)
#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
#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 */
#if !defined(CONFIG_DM_SCSI)
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];
#endif
/* 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
static 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]);
}
static 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]);
}
static 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 */
}
#ifdef CONFIG_BLK
static ulong scsi_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt,
void *buffer)
#else
static ulong scsi_read(struct blk_desc *block_dev, lbaint_t blknr,
lbaint_t blkcnt, void *buffer)
#endif
{
#ifdef CONFIG_BLK
struct blk_desc *block_dev = dev_get_uclass_platdata(dev);
#endif
lbaint_t start, blks;
uintptr_t buf_addr;
unsigned short smallblks = 0;
ccb *pccb = (ccb *)&tempccb;
/* Setup device */
pccb->target = block_dev->target;
pccb->lun = block_dev->lun;
buf_addr = (unsigned long)buffer;
start = blknr;
blks = blkcnt;
debug("\nscsi_read: dev %d startblk " LBAF
", blccnt " LBAF " buffer %lx\n",
block_dev->devnum, 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 = block_dev->blksz * blocks;
scsi_setup_read16(pccb, start, blocks);
start += blocks;
blks -= blocks;
} else
#endif
if (blks > SCSI_MAX_READ_BLK) {
pccb->datalen = block_dev->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 = block_dev->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
#ifdef CONFIG_BLK
static ulong scsi_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt,
const void *buffer)
#else
static ulong scsi_write(struct blk_desc *block_dev, lbaint_t blknr,
lbaint_t blkcnt, const void *buffer)
#endif
{
#ifdef CONFIG_BLK
struct blk_desc *block_dev = dev_get_uclass_platdata(dev);
#endif
lbaint_t start, blks;
uintptr_t buf_addr;
unsigned short smallblks;
ccb *pccb = (ccb *)&tempccb;
/* Setup device */
pccb->target = block_dev->target;
pccb->lun = block_dev->lun;
buf_addr = (unsigned long)buffer;
start = blknr;
blks = blkcnt;
debug("\n%s: dev %d startblk " LBAF ", blccnt " LBAF " buffer %lx\n",
__func__, block_dev->devnum, start, blks, (unsigned long)buffer);
do {
pccb->pdata = (unsigned char *)buf_addr;
if (blks > SCSI_MAX_WRITE_BLK) {
pccb->datalen = (block_dev->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 = block_dev->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;
}
#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
/* copy src to dest, skipping leading and trailing blanks
* and null terminate the string
*/
static 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';
}
static 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
*/
static 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 */
}
/**
* scsi_init_dev_desc_priv - initialize only SCSI specific blk_desc properties
*
* @dev_desc: Block device description pointer
*/
static void scsi_init_dev_desc_priv(struct blk_desc *dev_desc)
{
dev_desc->target = 0xff;
dev_desc->lun = 0xff;
dev_desc->log2blksz =
LOG2_INVALID(typeof(dev_desc->log2blksz));
dev_desc->type = DEV_TYPE_UNKNOWN;
dev_desc->vendor[0] = 0;
dev_desc->product[0] = 0;
dev_desc->revision[0] = 0;
dev_desc->removable = false;
#ifndef CONFIG_BLK
dev_desc->block_read = scsi_read;
dev_desc->block_write = scsi_write;
#endif
}
#if !defined(CONFIG_DM_SCSI)
/**
* scsi_init_dev_desc - initialize all SCSI specific blk_desc properties
*
* @dev_desc: Block device description pointer
* @devnum: Device number
*/
static void scsi_init_dev_desc(struct blk_desc *dev_desc, int devnum)
{
dev_desc->lba = 0;
dev_desc->blksz = 0;
dev_desc->if_type = IF_TYPE_SCSI;
dev_desc->devnum = devnum;
dev_desc->part_type = PART_TYPE_UNKNOWN;
scsi_init_dev_desc_priv(dev_desc);
}
#endif
/**
* scsi_detect_dev - Detect scsi device
*
* @target: target id
* @lun: target lun
* @dev_desc: block device description
*
* The scsi_detect_dev detects and fills a dev_desc structure when the device is
* detected.
*
* Return: 0 on success, error value otherwise
*/
static int scsi_detect_dev(int target, int lun, struct blk_desc *dev_desc)
{
unsigned char perq, modi;
lbaint_t capacity;
unsigned long blksz;
ccb *pccb = (ccb *)&tempccb;
pccb->target = target;
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) {
/*
* selection timeout => assuming no
* device present
*/
debug("Selection timeout ID %d\n",
pccb->target);
return -ETIMEDOUT;
}
scsi_print_error(pccb);
return -ENODEV;
}
perq = tempbuff[0];
modi = tempbuff[1];
if ((perq & 0x1f) == 0x1f)
return -ENODEV; /* skip unknown devices */
if ((modi & 0x80) == 0x80) /* drive is removable */
dev_desc->removable = true;
/* get info for this device */
scsi_ident_cpy((unsigned char *)dev_desc->vendor,
&tempbuff[8], 8);
scsi_ident_cpy((unsigned char *)dev_desc->product,
&tempbuff[16], 16);
scsi_ident_cpy((unsigned char *)dev_desc->revision,
&tempbuff[32], 4);
dev_desc->target = pccb->target;
dev_desc->lun = pccb->lun;
pccb->datalen = 0;
scsi_setup_test_unit_ready(pccb);
if (scsi_exec(pccb) != true) {
if (dev_desc->removable) {
dev_desc->type = perq;
goto removable;
}
scsi_print_error(pccb);
return -EINVAL;
}
if (scsi_read_capacity(pccb, &capacity, &blksz)) {
scsi_print_error(pccb);
return -EINVAL;
}
dev_desc->lba = capacity;
dev_desc->blksz = blksz;
dev_desc->log2blksz = LOG2(dev_desc->blksz);
dev_desc->type = perq;
removable:
return 0;
}
/*
* (re)-scan the scsi bus and reports scsi device info
* to the user if mode = 1
*/
#if defined(CONFIG_DM_SCSI)
int scsi_scan(int mode)
{
unsigned char i, lun;
struct uclass *uc;
struct udevice *dev; /* SCSI controller */
int ret;
if (mode == 1)
printf("scanning bus for devices...\n");
blk_unbind_all(IF_TYPE_SCSI);
ret = uclass_get(UCLASS_SCSI, &uc);
if (ret)
return ret;
uclass_foreach_dev(dev, uc) {
struct scsi_platdata *plat; /* scsi controller platdata */
/* probe SCSI controller driver */
ret = device_probe(dev);
if (ret)
return ret;
/* Get controller platdata */
plat = dev_get_platdata(dev);
for (i = 0; i < plat->max_id; i++) {
for (lun = 0; lun < plat->max_lun; lun++) {
struct udevice *bdev; /* block device */
/* block device description */
struct blk_desc _bd;
struct blk_desc *bdesc;
char str[10];
scsi_init_dev_desc_priv(&_bd);
ret = scsi_detect_dev(i, lun, &_bd);
if (ret)
/*
* no device detected?
* check the next lun.
*/
continue;
/*
* Create only one block device and do detection
* to make sure that there won't be a lot of
* block devices created
*/
snprintf(str, sizeof(str), "id%dlun%d", i, lun);
ret = blk_create_devicef(dev, "scsi_blk",
str, IF_TYPE_SCSI,
-1,
_bd.blksz,
_bd.blksz * _bd.lba,
&bdev);
if (ret) {
debug("Can't create device\n");
return ret;
}
bdesc = dev_get_uclass_platdata(bdev);
bdesc->target = i;
bdesc->lun = lun;
bdesc->removable = _bd.removable;
bdesc->type = _bd.type;
memcpy(&bdesc->vendor, &_bd.vendor,
sizeof(_bd.vendor));
memcpy(&bdesc->product, &_bd.product,
sizeof(_bd.product));
memcpy(&bdesc->revision, &_bd.revision,
sizeof(_bd.revision));
part_init(bdesc);
if (mode == 1) {
printf(" Device %d: ", 0);
dev_print(bdesc);
} /* if mode */
} /* next LUN */
}
}
return 0;
}
#else
int scsi_scan(int mode)
{
unsigned char i, lun;
int ret;
if (mode == 1)
printf("scanning bus for devices...\n");
for (i = 0; i < CONFIG_SYS_SCSI_MAX_DEVICE; i++)
scsi_init_dev_desc(&scsi_dev_desc[i], i);
scsi_max_devs = 0;
for (i = 0; i < CONFIG_SYS_SCSI_MAX_SCSI_ID; i++) {
for (lun = 0; lun < CONFIG_SYS_SCSI_MAX_LUN; lun++) {
ret = scsi_detect_dev(i, lun,
&scsi_dev_desc[scsi_max_devs]);
if (ret)
continue;
part_init(&scsi_dev_desc[scsi_max_devs]);
if (mode == 1) {
printf(" Device %d: ", 0);
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
return 0;
}
#endif
#ifdef CONFIG_BLK
static const struct blk_ops scsi_blk_ops = {
.read = scsi_read,
.write = scsi_write,
};
U_BOOT_DRIVER(scsi_blk) = {
.name = "scsi_blk",
.id = UCLASS_BLK,
.ops = &scsi_blk_ops,
};
#else
U_BOOT_LEGACY_BLK(scsi) = {
.if_typename = "scsi",
.if_type = IF_TYPE_SCSI,
.max_devs = CONFIG_SYS_SCSI_MAX_DEVICE,
.desc = scsi_dev_desc,
};
#endif
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