dfu: Introduction of the "dfu_hash_algo" env variable for checksum method setting
authorLukasz Majewski <l.majewski@samsung.com>
Mon, 12 May 2014 08:43:36 +0000 (10:43 +0200)
committerMarek Vasut <marex@denx.de>
Sun, 1 Jun 2014 17:18:00 +0000 (19:18 +0200)
Up till now the CRC32 of received data was calculated unconditionally.
The standard crc32 implementation causes long delay when large images
were uploaded.

The "dfu_hash_algo" environment variable gives the opportunity to
disable on demand the hash (crc32) calculation.
It can be done without the need to recompile the u-boot binary.

By default the crc32 is calculated, which means that legacy behavior
has been preserved.

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]

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Cc: Marek Vasut <marex@denx.de>
drivers/dfu/dfu.c

index a93810934ac90ec670792b979163d9a693b97d92..5878f991d92c538d74109476e370d1b16be0b0b1 100644 (file)
@@ -13,6 +13,7 @@
 #include <mmc.h>
 #include <fat.h>
 #include <dfu.h>
+#include <hash.h>
 #include <linux/list.h>
 #include <linux/compiler.h>
 
@@ -20,6 +21,7 @@ static bool dfu_reset_request;
 static LIST_HEAD(dfu_list);
 static int dfu_alt_num;
 static int alt_num_cnt;
+static struct hash_algo *dfu_hash_algo;
 
 bool dfu_reset(void)
 {
@@ -99,6 +101,29 @@ unsigned char *dfu_get_buf(void)
        return dfu_buf;
 }
 
+static char *dfu_get_hash_algo(void)
+{
+       char *s;
+
+       s = getenv("dfu_hash_algo");
+       /*
+        * By default the legacy behaviour to calculate the crc32 hash
+        * value is preserved.
+        *
+        * To disable calculation of the hash algorithm for received data
+        * specify the "dfu_hash_algo = disabled" at your board envs.
+        */
+       debug("%s: DFU hash method: %s\n", __func__, s ? s : "not specified");
+
+       if (!s || !strcmp(s, "crc32"))
+               return "crc32";
+
+       if (!strcmp(s, "disabled"))
+               return NULL;
+
+       return NULL;
+}
+
 static int dfu_write_buffer_drain(struct dfu_entity *dfu)
 {
        long w_size;
@@ -109,8 +134,9 @@ 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_hash_algo)
+               dfu_hash_algo->hash_update(dfu_hash_algo, &dfu->crc,
+                                          dfu->i_buf_start, w_size, 0);
 
        ret = dfu->write_medium(dfu, dfu->offset, dfu->i_buf_start, &w_size);
        if (ret)
@@ -138,7 +164,9 @@ int dfu_flush(struct dfu_entity *dfu, void *buf, int size, int blk_seq_num)
        if (dfu->flush_medium)
                ret = dfu->flush_medium(dfu);
 
-       printf("\nDFU complete CRC32: 0x%08x\n", dfu->crc);
+       if (dfu_hash_algo)
+               printf("\nDFU complete %s: 0x%08x\n", dfu_hash_algo->name,
+                      dfu->crc);
 
        /* clear everything */
        dfu_free_buf();
@@ -238,7 +266,11 @@ 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_hash_algo)
+                               dfu_hash_algo->hash_update(dfu_hash_algo,
+                                                          &dfu->crc, buf,
+                                                          chunk, 0);
+
                        dfu->i_buf += chunk;
                        dfu->b_left -= chunk;
                        dfu->r_left -= chunk;
@@ -322,7 +354,9 @@ 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_hash_algo)
+                       debug("%s: %s %s: 0x%x\n", __func__, dfu->name,
+                             dfu_hash_algo->name, dfu->crc);
                puts("\nUPLOAD ... done\nCtrl+C to exit ...\n");
 
                dfu_free_buf();
@@ -397,6 +431,14 @@ 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);
 
+       dfu_hash_algo = NULL;
+       s = dfu_get_hash_algo();
+       if (s) {
+               ret = hash_lookup_algo(s, &dfu_hash_algo);
+               if (ret)
+                       error("Hash algorithm %s not supported\n", s);
+       }
+
        dfu = calloc(sizeof(*dfu), dfu_alt_num);
        if (!dfu)
                return -1;