dfu: Support larger than memory transfers.

Previously we didn't support upload/download larger than available
memory.  This is pretty bad when you have to update your root filesystem
for example.

This patch removes that limitation (and the crashes when you transfered
any file larger than 4MB) by making raw image writes be done in chunks
and making file maximum size be configurable.

The sequence number is a 16 bit counter; make sure we handle rollover
correctly. This fixes the wrong transfers for large (> 256MB) images.

Also utilize a variable to handle initialization, so that we don't rely
on just the counter sent by the host.

Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Signed-off-by: Tom Rini <trini@ti.com>

2 files changed, 262 insertions, 89 deletions

diff --git a/drivers/dfu/dfu.c b/drivers/dfu/dfu.c
index e8477fb..609061d 100644
--- a/drivers/dfu/dfu.c
+++ b/drivers/dfu/dfu.c
@@ -44,90 +44,227 @@ static int dfu_find_alt_num(const char *s)
 static unsigned char __aligned(CONFIG_SYS_CACHELINE_SIZE)
 				     dfu_buf[DFU_DATA_BUF_SIZE];
 
+static int dfu_write_buffer_drain(struct dfu_entity *dfu)
+{
+	long w_size;
+	int ret;
+
+	/* flush size? */
+	w_size = dfu->i_buf - dfu->i_buf_start;
+	if (w_size == 0)
+		return 0;
+
+	/* update CRC32 */
+	dfu->crc = crc32(dfu->crc, dfu->i_buf_start, w_size);
+
+	ret = dfu->write_medium(dfu, dfu->offset, dfu->i_buf_start, &w_size);
+	if (ret)
+		debug("%s: Write error!\n", __func__);
+
+	/* point back */
+	dfu->i_buf = dfu->i_buf_start;
+
+	/* update offset */
+	dfu->offset += w_size;
+
+	puts("#");
+
+	return ret;
+}
+
 int dfu_write(struct dfu_entity *dfu, void *buf, int size, int blk_seq_num)
 {
-	static unsigned char *i_buf;
-	static int i_blk_seq_num;
-	long w_size = 0;
 	int ret = 0;
+	int tret;
+
+	debug("%s: name: %s buf: 0x%p size: 0x%x p_num: 0x%x offset: 0x%llx bufoffset: 0x%x\n",
+	      __func__, dfu->name, buf, size, blk_seq_num, dfu->offset,
+	      dfu->i_buf - dfu->i_buf_start);
+
+	if (!dfu->inited) {
+		/* initial state */
+		dfu->crc = 0;
+		dfu->offset = 0;
+		dfu->i_blk_seq_num = 0;
+		dfu->i_buf_start = dfu_buf;
+		dfu->i_buf_end = dfu_buf + sizeof(dfu_buf);
+		dfu->i_buf = dfu->i_buf_start;
+
+		dfu->inited = 1;
+	}
 
-	debug("%s: name: %s buf: 0x%p size: 0x%x p_num: 0x%x i_buf: 0x%p\n",
-	       __func__, dfu->name, buf, size, blk_seq_num, i_buf);
+	if (dfu->i_blk_seq_num != blk_seq_num) {
+		printf("%s: Wrong sequence number! [%d] [%d]\n",
+		       __func__, dfu->i_blk_seq_num, blk_seq_num);
+		return -1;
+	}
 
-	if (blk_seq_num == 0) {
-		i_buf = dfu_buf;
-		i_blk_seq_num = 0;
+	/* DFU 1.1 standard says:
+	 * The wBlockNum field is a block sequence number. It increments each
+	 * time a block is transferred, wrapping to zero from 65,535. It is used
+	 * to provide useful context to the DFU loader in the device."
+	 *
+	 * This means that it's a 16 bit counter that roll-overs at
+	 * 0xffff -> 0x0000. By having a typical 4K transfer block
+	 * we roll-over at exactly 256MB. Not very fun to debug.
+	 *
+	 * Handling rollover, and having an inited variable,
+	 * makes things work.
+	 */
+
+	/* handle rollover */
+	dfu->i_blk_seq_num = (dfu->i_blk_seq_num + 1) & 0xffff;
+
+	/* flush buffer if overflow */
+	if ((dfu->i_buf + size) > dfu->i_buf_end) {
+		tret = dfu_write_buffer_drain(dfu);
+		if (ret == 0)
+			ret = tret;
 	}
 
-	if (i_blk_seq_num++ != blk_seq_num) {
-		printf("%s: Wrong sequence number! [%d] [%d]\n",
-		       __func__, i_blk_seq_num, blk_seq_num);
+	/* we should be in buffer now (if not then size too large) */
+	if ((dfu->i_buf + size) > dfu->i_buf_end) {
+		printf("%s: Wrong size! [%d] [%d] - %d\n",
+		       __func__, dfu->i_blk_seq_num, blk_seq_num, size);
 		return -1;
 	}
 
-	memcpy(i_buf, buf, size);
-	i_buf += size;
+	memcpy(dfu->i_buf, buf, size);
+	dfu->i_buf += size;
 
+	/* if end or if buffer full flush */
+	if (size == 0 || (dfu->i_buf + size) > dfu->i_buf_end) {
+		tret = dfu_write_buffer_drain(dfu);
+		if (ret == 0)
+			ret = tret;
+	}
+
+	/* end? */
 	if (size == 0) {
-		/* Integrity check (if needed) */
-		debug("%s: %s %d [B] CRC32: 0x%x\n", __func__, dfu->name,
-		       i_buf - dfu_buf, crc32(0, dfu_buf, i_buf - dfu_buf));
+		/* Now try and flush to the medium if needed. */
+		if (dfu->flush_medium)
+			ret = dfu->flush_medium(dfu);
+		printf("\nDFU complete CRC32: 0x%08x\n", dfu->crc);
 
-		w_size = i_buf - dfu_buf;
-		ret = dfu->write_medium(dfu, dfu_buf, &w_size);
-		if (ret)
-			debug("%s: Write error!\n", __func__);
+		/* clear everything */
+		dfu->crc = 0;
+		dfu->offset = 0;
+		dfu->i_blk_seq_num = 0;
+		dfu->i_buf_start = dfu_buf;
+		dfu->i_buf_end = dfu_buf + sizeof(dfu_buf);
+		dfu->i_buf = dfu->i_buf_start;
+
+		dfu->inited = 0;
 
-		i_blk_seq_num = 0;
-		i_buf = NULL;
-		return ret;
 	}
 
-	return ret;
+	return ret = 0 ? size : ret;
+}
+
+static int dfu_read_buffer_fill(struct dfu_entity *dfu, void *buf, int size)
+{
+	long chunk;
+	int ret, readn;
+
+	readn = 0;
+	while (size > 0) {
+		/* get chunk that can be read */
+		chunk = min(size, dfu->b_left);
+		/* consume */
+		if (chunk > 0) {
+			memcpy(buf, dfu->i_buf, chunk);
+			dfu->crc = crc32(dfu->crc, buf, chunk);
+			dfu->i_buf += chunk;
+			dfu->b_left -= chunk;
+			size -= chunk;
+			buf += chunk;
+			readn += chunk;
+		}
+
+		/* all done */
+		if (size > 0) {
+			/* no more to read */
+			if (dfu->r_left == 0)
+				break;
+
+			dfu->i_buf = dfu->i_buf_start;
+			dfu->b_left = dfu->i_buf_end - dfu->i_buf_start;
+
+			/* got to read, but buffer is empty */
+			if (dfu->b_left > dfu->r_left)
+				dfu->b_left = dfu->r_left;
+			ret = dfu->read_medium(dfu, dfu->offset, dfu->i_buf,
+					&dfu->b_left);
+			if (ret != 0) {
+				debug("%s: Read error!\n", __func__);
+				return ret;
+			}
+			dfu->offset += dfu->b_left;
+			dfu->r_left -= dfu->b_left;
+
+			puts("#");
+		}
+	}
+
+	return readn;
 }
 
 int dfu_read(struct dfu_entity *dfu, void *buf, int size, int blk_seq_num)
 {
-	static unsigned char *i_buf;
-	static int i_blk_seq_num;
-	static long r_size;
-	static u32 crc;
 	int ret = 0;
 
 	debug("%s: name: %s buf: 0x%p size: 0x%x p_num: 0x%x i_buf: 0x%p\n",
-	       __func__, dfu->name, buf, size, blk_seq_num, i_buf);
-
-	if (blk_seq_num == 0) {
-		i_buf = dfu_buf;
-		ret = dfu->read_medium(dfu, i_buf, &r_size);
-		debug("%s: %s %ld [B]\n", __func__, dfu->name, r_size);
-		i_blk_seq_num = 0;
-		/* Integrity check (if needed) */
-		crc = crc32(0, dfu_buf, r_size);
+	       __func__, dfu->name, buf, size, blk_seq_num, dfu->i_buf);
+
+	if (!dfu->inited) {
+		ret = dfu->read_medium(dfu, 0, buf, &dfu->r_left);
+		if (ret != 0) {
+			debug("%s: failed to get r_left\n", __func__);
+			return ret;
+		}
+
+		debug("%s: %s %ld [B]\n", __func__, dfu->name, dfu->r_left);
+
+		dfu->i_blk_seq_num = 0;
+		dfu->crc = 0;
+		dfu->offset = 0;
+		dfu->i_buf_start = dfu_buf;
+		dfu->i_buf_end = dfu_buf + sizeof(dfu_buf);
+		dfu->i_buf = dfu->i_buf_start;
+		dfu->b_left = 0;
+
+		dfu->inited = 1;
 	}
 
-	if (i_blk_seq_num++ != blk_seq_num) {
+	if (dfu->i_blk_seq_num != blk_seq_num) {
 		printf("%s: Wrong sequence number! [%d] [%d]\n",
-		       __func__, i_blk_seq_num, blk_seq_num);
+		       __func__, dfu->i_blk_seq_num, blk_seq_num);
 		return -1;
 	}
+	/* handle rollover */
+	dfu->i_blk_seq_num = (dfu->i_blk_seq_num + 1) & 0xffff;
 
-	if (r_size >= size) {
-		memcpy(buf, i_buf, size);
-		i_buf += size;
-		r_size -= size;
-		return size;
-	} else {
-		memcpy(buf, i_buf, r_size);
-		i_buf += r_size;
-		debug("%s: %s CRC32: 0x%x\n", __func__, dfu->name, crc);
-		puts("UPLOAD ... done\nCtrl+C to exit ...\n");
+	ret = dfu_read_buffer_fill(dfu, buf, size);
+	if (ret < 0) {
+		printf("%s: Failed to fill buffer\n", __func__);
+		return -1;
+	}
+
+	if (ret < size) {
+		debug("%s: %s CRC32: 0x%x\n", __func__, dfu->name, dfu->crc);
+		puts("\nUPLOAD ... done\nCtrl+C to exit ...\n");
 
-		i_buf = NULL;
-		i_blk_seq_num = 0;
-		crc = 0;
-		return r_size;
+		dfu->i_blk_seq_num = 0;
+		dfu->crc = 0;
+		dfu->offset = 0;
+		dfu->i_buf_start = dfu_buf;
+		dfu->i_buf_end = dfu_buf + sizeof(dfu_buf);
+		dfu->i_buf = dfu->i_buf_start;
+		dfu->b_left = 0;
+
+		dfu->inited = 0;
 	}
+
 	return ret;
 }
 
diff --git a/drivers/dfu/dfu_mmc.c b/drivers/dfu/dfu_mmc.c
index afd3506..e2f3978 100644
--- a/drivers/dfu/dfu_mmc.c
+++ b/drivers/dfu/dfu_mmc.c
@@ -22,6 +22,7 @@
 #include <common.h>
 #include <malloc.h>
 #include <errno.h>
+#include <div64.h>
 #include <dfu.h>
 
 enum dfu_mmc_op {
@@ -29,32 +30,51 @@ enum dfu_mmc_op {
 	DFU_OP_WRITE,
 };
 
+static unsigned char __aligned(CONFIG_SYS_CACHELINE_SIZE)
+				dfu_file_buf[CONFIG_SYS_DFU_MAX_FILE_SIZE];
+static long dfu_file_buf_len;
+
 static int mmc_block_op(enum dfu_mmc_op op, struct dfu_entity *dfu,
-			void *buf, long *len)
+			u64 offset, void *buf, long *len)
 {
 	char cmd_buf[DFU_CMD_BUF_SIZE];
+	u32 blk_start, blk_count;
+
+	/*
+	 * We must ensure that we work in lba_blk_size chunks, so ALIGN
+	 * this value.
+	 */
+	*len = ALIGN(*len, dfu->data.mmc.lba_blk_size);
+
+	blk_start = dfu->data.mmc.lba_start +
+			(u32)lldiv(offset, dfu->data.mmc.lba_blk_size);
+	blk_count = *len / dfu->data.mmc.lba_blk_size;
+	if (blk_start + blk_count >
+			dfu->data.mmc.lba_start + dfu->data.mmc.lba_size) {
+		puts("Request would exceed designated area!\n");
+		return -EINVAL;
+	}
 
-	sprintf(cmd_buf, "mmc %s 0x%x %x %x",
+	sprintf(cmd_buf, "mmc %s %p %x %x",
 		op == DFU_OP_READ ? "read" : "write",
-		(unsigned int) buf,
-		dfu->data.mmc.lba_start,
-		dfu->data.mmc.lba_size);
-
-	if (op == DFU_OP_READ)
-		*len = dfu->data.mmc.lba_blk_size * dfu->data.mmc.lba_size;
+		 buf, blk_start, blk_count);
 
 	debug("%s: %s 0x%p\n", __func__, cmd_buf, cmd_buf);
 	return run_command(cmd_buf, 0);
 }
 
-static inline int mmc_block_write(struct dfu_entity *dfu, void *buf, long *len)
+static int mmc_file_buffer(struct dfu_entity *dfu, void *buf, long *len)
 {
-	return mmc_block_op(DFU_OP_WRITE, dfu, buf, len);
-}
+	if (dfu_file_buf_len + *len > CONFIG_SYS_DFU_MAX_FILE_SIZE) {
+		dfu_file_buf_len = 0;
+		return -EINVAL;
+	}
 
-static inline int mmc_block_read(struct dfu_entity *dfu, void *buf, long *len)
-{
-	return mmc_block_op(DFU_OP_READ, dfu, buf, len);
+	/* Add to the current buffer. */
+	memcpy(dfu_file_buf + dfu_file_buf_len, buf, *len);
+	dfu_file_buf_len += *len;
+
+	return 0;
 }
 
 static int mmc_file_op(enum dfu_mmc_op op, struct dfu_entity *dfu,
@@ -66,20 +86,23 @@ static int mmc_file_op(enum dfu_mmc_op op, struct dfu_entity *dfu,
 
 	switch (dfu->layout) {
 	case DFU_FS_FAT:
-		sprintf(cmd_buf, "fat%s mmc %d:%d 0x%x %s %lx",
+		sprintf(cmd_buf, "fat%s mmc %d:%d 0x%x %s",
 			op == DFU_OP_READ ? "load" : "write",
 			dfu->data.mmc.dev, dfu->data.mmc.part,
-			(unsigned int) buf, dfu->name, *len);
+			(unsigned int) buf, dfu->name);
+		if (op == DFU_OP_WRITE)
+			sprintf(cmd_buf + strlen(cmd_buf), " %lx", *len);
 		break;
 	case DFU_FS_EXT4:
-		sprintf(cmd_buf, "ext4%s mmc %d:%d 0x%x /%s %ld",
+		sprintf(cmd_buf, "ext4%s mmc %d:%d 0x%x /%s",
 			op == DFU_OP_READ ? "load" : "write",
 			dfu->data.mmc.dev, dfu->data.mmc.part,
-			(unsigned int) buf, dfu->name, *len);
+			(unsigned int) buf, dfu->name);
 		break;
 	default:
 		printf("%s: Layout (%s) not (yet) supported!\n", __func__,
 		       dfu_get_layout(dfu->layout));
+		return -1;
 	}
 
 	debug("%s: %s 0x%p\n", __func__, cmd_buf, cmd_buf);
@@ -102,27 +125,18 @@ static int mmc_file_op(enum dfu_mmc_op op, struct dfu_entity *dfu,
 	return ret;
 }
 
-static inline int mmc_file_write(struct dfu_entity *dfu, void *buf, long *len)
-{
-	return mmc_file_op(DFU_OP_WRITE, dfu, buf, len);
-}
-
-static inline int mmc_file_read(struct dfu_entity *dfu, void *buf, long *len)
-{
-	return mmc_file_op(DFU_OP_READ, dfu, buf, len);
-}
-
-int dfu_write_medium_mmc(struct dfu_entity *dfu, void *buf, long *len)
+int dfu_write_medium_mmc(struct dfu_entity *dfu,
+		u64 offset, void *buf, long *len)
 {
 	int ret = -1;
 
 	switch (dfu->layout) {
 	case DFU_RAW_ADDR:
-		ret = mmc_block_write(dfu, buf, len);
+		ret = mmc_block_op(DFU_OP_WRITE, dfu, offset, buf, len);
 		break;
 	case DFU_FS_FAT:
 	case DFU_FS_EXT4:
-		ret = mmc_file_write(dfu, buf, len);
+		ret = mmc_file_buffer(dfu, buf, len);
 		break;
 	default:
 		printf("%s: Layout (%s) not (yet) supported!\n", __func__,
@@ -132,17 +146,34 @@ int dfu_write_medium_mmc(struct dfu_entity *dfu, void *buf, long *len)
 	return ret;
 }
 
-int dfu_read_medium_mmc(struct dfu_entity *dfu, void *buf, long *len)
+int dfu_flush_medium_mmc(struct dfu_entity *dfu)
+{
+	int ret = 0;
+
+	if (dfu->layout != DFU_RAW_ADDR) {
+		/* Do stuff here. */
+		ret = mmc_file_op(DFU_OP_WRITE, dfu, &dfu_file_buf,
+				&dfu_file_buf_len);
+
+		/* Now that we're done */
+		dfu_file_buf_len = 0;
+	}
+
+	return ret;
+}
+
+int dfu_read_medium_mmc(struct dfu_entity *dfu, u64 offset, void *buf,
+		long *len)
 {
 	int ret = -1;
 
 	switch (dfu->layout) {
 	case DFU_RAW_ADDR:
-		ret = mmc_block_read(dfu, buf, len);
+		ret = mmc_block_op(DFU_OP_READ, dfu, offset, buf, len);
 		break;
 	case DFU_FS_FAT:
 	case DFU_FS_EXT4:
-		ret = mmc_file_read(dfu, buf, len);
+		ret = mmc_file_op(DFU_OP_READ, dfu, buf, len);
 		break;
 	default:
 		printf("%s: Layout (%s) not (yet) supported!\n", __func__,
@@ -181,14 +212,15 @@ int dfu_fill_entity_mmc(struct dfu_entity *dfu, char *s)
 
 		mmc = find_mmc_device(dev);
 		if (mmc == NULL || mmc_init(mmc)) {
-			printf("%s: could not find mmc device #%d!\n", __func__, dev);
+			printf("%s: could not find mmc device #%d!\n",
+			       __func__, dev);
 			return -ENODEV;
 		}
 
 		blk_dev = &mmc->block_dev;
 		if (get_partition_info(blk_dev, part, &partinfo) != 0) {
 			printf("%s: could not find partition #%d on mmc device #%d!\n",
-					__func__, part, dev);
+			       __func__, part, dev);
 			return -ENODEV;
 		}
 
@@ -208,6 +240,10 @@ int dfu_fill_entity_mmc(struct dfu_entity *dfu, char *s)
 
 	dfu->read_medium = dfu_read_medium_mmc;
 	dfu->write_medium = dfu_write_medium_mmc;
+	dfu->flush_medium = dfu_flush_medium_mmc;
+
+	/* initial state */
+	dfu->inited = 0;
 
 	return 0;
 }