Add max_bytes_per_req to scsi_platdata to enable the host driver to limit the number of bytes that can be read/written per request.
Signed-off-by: Faiz Abbas faiz_abbas@ti.com --- drivers/scsi/scsi.c | 45 ++++++++++++++++++++++++++------------------- include/scsi.h | 2 ++ 2 files changed, 28 insertions(+), 19 deletions(-)
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index 009d80faa7..0bce22a51a 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -45,7 +45,7 @@ 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_MAX_BLK 0xFFFF #define SCSI_LBA48_READ 0xFFFFFFF
static void scsi_print_error(struct scsi_cmd *pccb) @@ -146,7 +146,8 @@ static ulong scsi_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, { struct blk_desc *block_dev = dev_get_uclass_platdata(dev); struct udevice *bdev = dev->parent; - lbaint_t start, blks; + struct scsi_platdata *uc_plat = dev_get_uclass_platdata(bdev); + lbaint_t start, blks, max_blks; uintptr_t buf_addr; unsigned short smallblks = 0; struct scsi_cmd *pccb = (struct scsi_cmd *)&tempccb; @@ -157,6 +158,11 @@ static ulong scsi_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, buf_addr = (unsigned long)buffer; start = blknr; blks = blkcnt; + if (uc_plat->max_bytes_per_req) + max_blks = uc_plat->max_bytes_per_req / block_dev->blksz; + else + max_blks = SCSI_MAX_BLK; + debug("\nscsi_read: dev %d startblk " LBAF ", blccnt " LBAF " buffer %lx\n", block_dev->devnum, start, blks, (unsigned long)buffer); @@ -165,20 +171,19 @@ static ulong scsi_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, #ifdef CONFIG_SYS_64BIT_LBA if (start > SCSI_LBA48_READ) { unsigned long blocks; - blocks = min_t(lbaint_t, blks, SCSI_MAX_READ_BLK); + blocks = min_t(lbaint_t, blks, max_blks); 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; + if (blks > max_blks) { + pccb->datalen = block_dev->blksz * max_blks; + smallblks = max_blks; scsi_setup_read_ext(pccb, start, smallblks); - start += SCSI_MAX_READ_BLK; - blks -= SCSI_MAX_READ_BLK; + start += max_blks; + blks -= max_blks; } else { pccb->datalen = block_dev->blksz * blks; smallblks = (unsigned short)blks; @@ -205,15 +210,13 @@ static ulong scsi_read(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, * scsi_write */
-/* Almost the maximum amount of the scsi_ext command.. */ -#define SCSI_MAX_WRITE_BLK 0xFFFF - static ulong scsi_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, const void *buffer) { struct blk_desc *block_dev = dev_get_uclass_platdata(dev); struct udevice *bdev = dev->parent; - lbaint_t start, blks; + struct scsi_platdata *uc_plat = dev_get_uclass_platdata(bdev); + lbaint_t start, blks, max_blks; uintptr_t buf_addr; unsigned short smallblks; struct scsi_cmd *pccb = (struct scsi_cmd *)&tempccb; @@ -224,17 +227,21 @@ static ulong scsi_write(struct udevice *dev, lbaint_t blknr, lbaint_t blkcnt, buf_addr = (unsigned long)buffer; start = blknr; blks = blkcnt; + if (uc_plat->max_bytes_per_req) + max_blks = uc_plat->max_bytes_per_req / block_dev->blksz; + else + max_blks = SCSI_MAX_BLK; + 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; + if (blks > max_blks) { + pccb->datalen = block_dev->blksz * max_blks; + smallblks = max_blks; scsi_setup_write_ext(pccb, start, smallblks); - start += SCSI_MAX_WRITE_BLK; - blks -= SCSI_MAX_WRITE_BLK; + start += max_blks; + blks -= max_blks; } else { pccb->datalen = block_dev->blksz * blks; smallblks = (unsigned short)blks; diff --git a/include/scsi.h b/include/scsi.h index 81ab43c842..963abe2b13 100644 --- a/include/scsi.h +++ b/include/scsi.h @@ -163,11 +163,13 @@ struct scsi_cmd { * @base: Controller base address * @max_lun: Maximum number of logical units * @max_id: Maximum number of target ids + * @max_bytes_per_req: Maximum number of bytes per read/write request */ struct scsi_platdata { unsigned long base; unsigned long max_lun; unsigned long max_id; + unsigned long max_bytes_per_req; };
/* Operations for SCSI */