[U-Boot] [PATCH 3/4] MMC Multi-block Support

[Alagu Sankar]

Added Multi-Block Read support for Generic MMC. Modified existing multi-block
write to limit the maximum number of blocks per transfer.  This feature is
enabled with CONFIG_MMC_MBLOCK option.  A new member is added in the mmc
structure for the host controller to specify the maximum number of blocks it
supports.

Signed-off-by: Alagu Sankar <alagusankar at embwise.com>
---
 drivers/mmc/mmc.c |  156 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/mmc.h     |    3 +
 2 files changed, 159 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index e7abf94..3f5a200 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -77,6 +77,7 @@ struct mmc *find_mmc_device(int dev_num)
 	return NULL;
 }
 
+#ifndef CONFIG_MMC_MBLOCK
 static ulong
 mmc_bwrite(int dev_num, ulong start, lbaint_t blkcnt, const void*src)
 {
@@ -238,6 +239,156 @@ static ulong mmc_bread(int dev_num, ulong start, lbaint_t blkcnt, void *dst)
 	return blkcnt;
 }
 
+#else
+
+static int mmc_write_blocks(struct mmc *mmc, const char *src, uint start,
+		uint blkcnt)
+{
+	struct mmc_cmd cmd;
+	struct mmc_data data;
+	int err;
+	int blklen;
+
+	blklen = mmc->write_bl_len;
+
+	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;
+	else
+		cmd.cmdidx = MMC_CMD_WRITE_SINGLE_BLOCK;
+
+	if (mmc->high_capacity)
+		cmd.cmdarg = start;
+	else
+		cmd.cmdarg = start * blklen;
+
+	cmd.resp_type = MMC_RSP_R1;
+	cmd.flags = 0;
+
+	data.src = src;
+	data.blocks = blkcnt;
+	data.blocksize = blklen;
+	data.flags = MMC_DATA_WRITE;
+
+	err = mmc_send_cmd(mmc, &cmd, &data);
+
+	if (err) {
+		printf("mmc write failed\n\r");
+		return err;
+	}
+
+	if (blkcnt > 1) {
+		cmd.cmdidx = MMC_CMD_STOP_TRANSMISSION;
+		cmd.cmdarg = 0;
+		cmd.resp_type = MMC_RSP_R1b;
+		cmd.flags = 0;
+		err = mmc_send_cmd(mmc, &cmd, NULL);
+	}
+
+	return err;
+}
+
+static ulong
+mmc_bwrite(int dev_num, ulong start, lbaint_t blkcnt, const void *src)
+{
+	int err;
+	int i;
+	struct mmc *mmc = find_mmc_device(dev_num);
+	uint b_max = mmc->b_max;
+
+	if (!mmc)
+		return 0;
+
+	for (i = blkcnt; i > 0; i -= b_max) {
+		uint blocks = (i > b_max) ? b_max : i;
+
+		err = mmc_write_blocks(mmc, src, start, blocks);
+		if (err)
+			return blkcnt - i;
+		start += blocks;
+		src += (mmc->write_bl_len * blocks);
+	}
+
+	return blkcnt;
+}
+
+int mmc_read_blocks(struct mmc *mmc, void *dst, uint blocknum, uint blkcnt)
+{
+	int err;
+	struct mmc_cmd cmd;
+	struct mmc_data data;
+
+	if (blkcnt > 1)
+		cmd.cmdidx = MMC_CMD_READ_MULTIPLE_BLOCK;
+	else
+		cmd.cmdidx = MMC_CMD_READ_SINGLE_BLOCK;
+
+	if (mmc->high_capacity)
+		cmd.cmdarg = blocknum;
+	else
+		cmd.cmdarg = blocknum * mmc->read_bl_len;
+
+	cmd.resp_type = MMC_RSP_R1;
+	cmd.flags = 0;
+
+	data.dest = dst;
+	data.blocks = blkcnt;
+	data.blocksize = mmc->read_bl_len;
+	data.flags = MMC_DATA_READ;
+
+	err = mmc_send_cmd(mmc, &cmd, &data);
+	if (err)
+		return err;
+
+	if (blkcnt > 1) {
+		cmd.cmdidx = MMC_CMD_STOP_TRANSMISSION;
+		cmd.cmdarg = 0;
+		cmd.resp_type = MMC_RSP_R1b;
+		cmd.flags = 0;
+		err = mmc_send_cmd(mmc, &cmd, NULL);
+	}
+
+	return err;
+}
+
+static ulong mmc_bread(int dev_num, ulong start, lbaint_t blkcnt, void *dst)
+{
+	int err;
+	int i;
+	struct mmc *mmc = find_mmc_device(dev_num);
+	uint b_max = mmc->b_max;
+
+	if (!mmc)
+		return 0;
+
+	/* We always do full block reads from the card */
+	err = mmc_set_blocklen(mmc, mmc->read_bl_len);
+	if (err)
+		return 0;
+
+	for (i = blkcnt; i > 0; i -= b_max) {
+		uint blocks = (i > b_max) ? b_max : i;
+
+		err = mmc_read_blocks(mmc, dst, start, blocks);
+		if (err) {
+			printf("block read failed: %d\n", err);
+			return blkcnt - i;
+		}
+		start += blocks;
+		dst += (mmc->read_bl_len * blocks);
+	}
+
+	return blkcnt;
+}
+
+#endif
+
 int mmc_go_idle(struct mmc* mmc)
 {
 	struct mmc_cmd cmd;
@@ -858,6 +1009,11 @@ int mmc_register(struct mmc *mmc)
 	mmc->block_dev.block_read = mmc_bread;
 	mmc->block_dev.block_write = mmc_bwrite;
 
+#ifdef CONFIG_MMC_MBLOCK
+	if (mmc->b_max == 0)
+		mmc->b_max = 1;
+#endif
+
 	INIT_LIST_HEAD (&mmc->link);
 
 	list_add_tail (&mmc->link, &mmc_devices);
diff --git a/include/mmc.h b/include/mmc.h
index 8973bc7..04c7eaf 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -264,6 +264,9 @@ struct mmc {
 			struct mmc_cmd *cmd, struct mmc_data *data);
 	void (*set_ios)(struct mmc *mmc);
 	int (*init)(struct mmc *mmc);
+#ifdef CONFIG_MMC_MBLOCK
+	uint b_max;
+#endif
 };
 
 int mmc_register(struct mmc *mmc);
-- 
1.6.0.6