mmc: seperate block number into small parts for multi-write cmd
Constraint the mmc framework to only send no more than 65535
blocks in one go during the multi-write command. This constraint
comes due to the limitation of 16bit width block counter register
at some hardware.
Signed-off-by: Lei Wen <leiwen@marvell.com>
Cc: Reinhard Meyer <u-boot@emk-elektronik.de>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index c543d83..eb7bfb3 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -78,17 +78,11 @@
}
static ulong
-mmc_bwrite(int dev_num, ulong start, lbaint_t blkcnt, const void*src)
+mmc_write_blocks(struct mmc *mmc, ulong start, lbaint_t blkcnt, const void*src)
{
struct mmc_cmd cmd;
struct mmc_data data;
- int err;
- int stoperr = 0;
- struct mmc *mmc = find_mmc_device(dev_num);
- int blklen;
-
- if (!mmc)
- return -1;
+ int blklen, err;
blklen = mmc->write_bl_len;
@@ -97,12 +91,6 @@
start + blkcnt, mmc->block_dev.lba);
return 0;
}
- err = mmc_set_blocklen(mmc, mmc->write_bl_len);
-
- if (err) {
- printf("set write bl len failed\n\r");
- return err;
- }
if (blkcnt > 1)
cmd.cmdidx = MMC_CMD_WRITE_MULTIPLE_BLOCK;
@@ -134,12 +122,48 @@
cmd.cmdarg = 0;
cmd.resp_type = MMC_RSP_R1b;
cmd.flags = 0;
- stoperr = mmc_send_cmd(mmc, &cmd, NULL);
+ err = mmc_send_cmd(mmc, &cmd, NULL);
+ if (err) {
+ printf("mmc fail to send stop cmd\n\r");
+ return err;
+ }
}
return blkcnt;
}
+static ulong
+mmc_bwrite(int dev_num, ulong start, lbaint_t blkcnt, const void*src)
+{
+ int err;
+ struct mmc *mmc = find_mmc_device(dev_num);
+ lbaint_t cur, blocks_todo = blkcnt;
+
+ if (!mmc)
+ return -1;
+
+ err = mmc_set_blocklen(mmc, mmc->write_bl_len);
+ if (err) {
+ printf("set write bl len failed\n\r");
+ return err;
+ }
+
+ do {
+ /*
+ * The 65535 constraint comes from some hardware has
+ * only 16 bit width block number counter
+ */
+ cur = (blocks_todo > 65535) ? 65535 : blocks_todo;
+ if(mmc_write_blocks(mmc, start, cur, src) != cur)
+ return -1;
+ blocks_todo -= cur;
+ start += cur;
+ src += cur * mmc->write_bl_len;
+ } while (blocks_todo > 0);
+
+ return blkcnt;
+}
+
int mmc_read_block(struct mmc *mmc, void *dst, uint blocknum)
{
struct mmc_cmd cmd;