Hi Pantelis,
Hi Lukasz,
On Mar 31, 2014, at 11:48 AM, Lukasz Majewski wrote:
Up till now the CRC32 of received data was calculated unconditionally. The standard crc32 implementation causes long delays when large images were uploaded.
The "dfu_checksum_method" environment variable gives the opportunity to enable on demand (when e.g. debugging) the crc32 calculation. It can be done without need to recompile the u-boot binary.
By default the crc32 is not calculated.
Tests results: 400 MiB ums.img file With crc32 calculation: 65 sec [avg 6.29 MB/s] Without crc32 calculation: 25 sec [avg 16.17 MB/s]
That's interesting; I'm surprised that there's so much difference. Can we get some info about the environment? I.e. board, whether cache is enabled etc.
Board Exynos4412 - Trats2. Cache L1 enabled, cache L2 disabled.
Crc32 is calculated for 32 MiB chunks of data in the received buffer. I'm using the standard software crc32 u-boot's implementation. It is the same as the one for perl-crc32 debian package.
The crc table is per byte and I guess lookups maybe expensive.
It seems so. Moreover the Exynos4412 has HW crypto engine which supports SHA1, MD5 and other algorithms. Unfortunately it doesn't provide speedup for crc32.
Regards
-- Pantelis
Signed-off-by: Lukasz Majewski l.majewski@samsung.com
drivers/dfu/dfu.c | 34 ++++++++++++++++++++++++++++++---- include/dfu.h | 5 +++++ 2 files changed, 35 insertions(+), 4 deletions(-)
diff --git a/drivers/dfu/dfu.c b/drivers/dfu/dfu.c index e15f959..5d50b47 100644 --- a/drivers/dfu/dfu.c +++ b/drivers/dfu/dfu.c @@ -20,6 +20,7 @@ static bool dfu_reset_request; static LIST_HEAD(dfu_list); static int dfu_alt_num; static int alt_num_count; +static int dfu_checksum_method;
bool dfu_reset(void) { @@ -99,6 +100,23 @@ unsigned char *dfu_get_buf(void) return dfu_buf; }
+static int dfu_get_checksum_method(void) +{
- char *s;
- s = getenv("dfu_checksum_method");
- if (!s)
return DFU_NO_CHECKSUM;- if (!strcmp(s, "crc32")) {
debug("%s: DFU checksum method: %s\n", __func__,s);
return DFU_CRC32;- } else {
error("DFU checksum method: %s not supported!\n",s);
return -EINVAL;- }
+}
static int dfu_write_buffer_drain(struct dfu_entity *dfu) { long w_size; @@ -109,8 +127,8 @@ static int dfu_write_buffer_drain(struct dfu_entity *dfu) if (w_size == 0) return 0;
- /* update CRC32 */
- dfu->crc = crc32(dfu->crc, dfu->i_buf_start, w_size);
- if (dfu_checksum_method == DFU_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) @@ -234,7 +252,8 @@ static int dfu_read_buffer_fill(struct dfu_entity *dfu, void *buf, int size) /* consume */ if (chunk > 0) { memcpy(buf, dfu->i_buf, chunk);
dfu->crc = crc32(dfu->crc, buf, chunk);
if (dfu_checksum_method == DFU_CRC32)dfu->crc = crc32(dfu->crc, buf,chunk); dfu->i_buf += chunk; dfu->b_left -= chunk; dfu->r_left -= chunk; @@ -318,7 +337,9 @@ int dfu_read(struct dfu_entity *dfu, void *buf, int size, int blk_seq_num) }
if (ret < size) {
debug("%s: %s CRC32: 0x%x\n", __func__, dfu->name,dfu->crc);
if (dfu_checksum_method == DFU_CRC32)debug("%s: %s CRC32: 0x%x\n", __func__,dfu->name,
dfu->crc);puts("\nUPLOAD ... done\nCtrl+C to exit ...\n");
dfu_free_buf();
@@ -393,6 +414,11 @@ int dfu_config_entities(char *env, char *interface, int num) dfu_alt_num = dfu_find_alt_num(env); debug("%s: dfu_alt_num=%d\n", __func__, dfu_alt_num);
- ret = dfu_get_checksum_method();
- if (ret < 0)
return ret;- dfu_checksum_method = ret;
- dfu = calloc(sizeof(*dfu), dfu_alt_num); if (!dfu) return -1;
diff --git a/include/dfu.h b/include/dfu.h index 751f0fd..855d6dc 100644 --- a/include/dfu.h +++ b/include/dfu.h @@ -37,6 +37,11 @@ enum dfu_op { DFU_OP_WRITE, };
+enum dfu_checksum {
- DFU_NO_CHECKSUM = 0,
- DFU_CRC32,
+};
#define DFU_NOT_SUPPORTED -1
struct mmc_internal_data {
1.7.10.4