tftp: get the tftp block size from config file and from the environment

Increasing the block size is useful if CONFIG_IP_DEFRAG is
used. Howerver, the last fragments in a burst may overflow the
receiving ethernet, so the default is left at 1468, with thre new
CONFIG_TFTP_BLOCKSIZE for config files. Further, "tftpblocksize"
can be set in the environment.

Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
This commit is contained in:
Alessandro Rubini 2009-08-07 13:59:06 +02:00 committed by Ben Warren
parent 5cfaa4e54d
commit 89ba81d107
1 changed files with 11 additions and 2 deletions

View File

@ -84,8 +84,14 @@ extern flash_info_t flash_info[];
/* 512 is poor choice for ethernet, MTU is typically 1500.
* Minus eth.hdrs thats 1468. Can get 2x better throughput with
* almost-MTU block sizes. At least try... fall back to 512 if need be.
* (but those using CONFIG_IP_DEFRAG may want to set a larger block in cfg file)
*/
#ifdef CONFIG_TFTP_BLOCKSIZE
#define TFTP_MTU_BLOCKSIZE CONFIG_TFTP_BLOCKSIZE
#else
#define TFTP_MTU_BLOCKSIZE 1468
#endif
static unsigned short TftpBlkSize=TFTP_BLOCK_SIZE;
static unsigned short TftpBlkSizeOption=TFTP_MTU_BLOCKSIZE;
@ -466,9 +472,12 @@ TftpTimeout (void)
void
TftpStart (void)
{
#ifdef CONFIG_TFTP_PORT
char *ep; /* Environment pointer */
#endif
/* Allow the user to choose tftpblocksize */
if ((ep = getenv("tftpblocksize")) != NULL)
TftpBlkSizeOption = simple_strtol(ep, NULL, 10);
debug("tftp block size is %i\n", TftpBlkSizeOption);
TftpServerIP = NetServerIP;
if (BootFile[0] == '\0') {