From 0e285b503c41bb53f6ef962e6f9c942c1ca47cc6 Mon Sep 17 00:00:00 2001 From: Stephen Warren Date: Wed, 11 Jun 2014 12:47:27 -0600 Subject: dfu: fix some issues with reads/uploads DFU read support appears to rely upon dfu->read_medium() updating the passed-by-reference len parameter to indicate the remaining size available for reading. dfu_read_medium_mmc() never does this, and the implementation of dfu_read_medium_nand() will only work if called just once; it hard-codes the value to the total size of the NAND device irrespective of read offset. I believe that overloading dfu->read_medium() is confusing. As such, this patch introduces a new function dfu->get_medium_size() which can be used to explicitly find out the medium size, and nothing else. dfu_read() is modified to use this function to set the initial value for dfu->r_left, rather than attempting to use the side-effects of dfu->read_medium() for this purpose. Due to this change, dfu_read() must initially set dfu->b_left to 0, since no data has been read. dfu_read_buffer_fill() must also be modified not to adjust dfu->r_left when simply copying data from dfu->i_buf_start to the upload request buffer. r_left represents the amount of data left to be read from HW. That value is not affected by the memcpy(), but only by calls to dfu->read_medium(). After this change, I can read from either a 4MB or 1.5MB chunk of a 4MB eMMC boot partion with CONFIG_SYS_DFU_DATA_BUF_SIZE==1MB. Without this change, attempting to do that would result in DFU read returning no data at all due to r_left never being set. Signed-off-by: Stephen Warren --- drivers/dfu/dfu.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'drivers/dfu/dfu.c') diff --git a/drivers/dfu/dfu.c b/drivers/dfu/dfu.c index dc09ff6..dab5e70 100644 --- a/drivers/dfu/dfu.c +++ b/drivers/dfu/dfu.c @@ -267,7 +267,6 @@ static int dfu_read_buffer_fill(struct dfu_entity *dfu, void *buf, int size) dfu->i_buf += chunk; dfu->b_left -= chunk; - dfu->r_left -= chunk; size -= chunk; buf += chunk; readn += chunk; @@ -313,10 +312,19 @@ int dfu_read(struct dfu_entity *dfu, void *buf, int size, int blk_seq_num) if (dfu->i_buf_start == NULL) return -ENOMEM; - ret = dfu->read_medium(dfu, 0, dfu->i_buf_start, &dfu->r_left); - if (ret != 0) { - debug("%s: failed to get r_left\n", __func__); - return ret; + dfu->r_left = dfu->get_medium_size(dfu); + if (dfu->r_left < 0) + return dfu->r_left; + switch (dfu->layout) { + case DFU_RAW_ADDR: + case DFU_RAM_ADDR: + break; + default: + if (dfu->r_left >= dfu_buf_size) { + printf("%s: File too big for buffer\n", + __func__); + return -EOVERFLOW; + } } debug("%s: %s %ld [B]\n", __func__, dfu->name, dfu->r_left); @@ -326,7 +334,7 @@ int dfu_read(struct dfu_entity *dfu, void *buf, int size, int blk_seq_num) dfu->offset = 0; dfu->i_buf_end = dfu_get_buf() + dfu_buf_size; dfu->i_buf = dfu->i_buf_start; - dfu->b_left = min(dfu_buf_size, dfu->r_left); + dfu->b_left = 0; dfu->bad_skip = 0; -- cgit v1.1