scsi: Add max_bytes_per_req to scsi_platdata
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>
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 1b9f25a..e55bb25 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -45,7 +45,7 @@
#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)
@@ -147,7 +147,8 @@
{
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;
@@ -158,6 +159,11 @@
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);
@@ -166,20 +172,19 @@
#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;
@@ -206,15 +211,13 @@
* 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;
@@ -225,17 +228,21 @@
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;