On Mon, Nov 29, 2004 at 03:33:16PM +0100, Anders Larsen wrote:
"VanBaren, Gerald (AGRE)" Gerald.VanBaren@smiths-aerospace.com:
The proper fix is, for your board, change the assignment "vu_long *dummy = 0x00000000;" to point to writable RAM on your board.
This is the purpose of CFG_MEMTEST_SCRATCH.
Please, please read the README, which says: "- CFG_MEMTEST_SCRATCH: Scratch address used by the alternate memory test You only need to set this if address zero isn't writeable"
Ah, sorry. I looked only at code and it seemed wrong to me. See below.
The last statement implies that you DO need to set CFG_MEMTEST_SCRATCH if address zero ISN'T writeable.
No need to change any code at all.
Thanks, now I see the code works how author intended. But I do not agree with the way how it is written. NULL pointer means invalid pointer, while "vu_long *dummy = 0x00000000;" means valid pointer to address zero (and yes I know they both will lead to the same machine code ;-)) Consider patch bellow.
Now a little question. Would you mind a patch making scratch area optional?
Regards, ladis
Index: common/cmd_mem.c =================================================================== RCS file: /cvsroot/u-boot/u-boot/common/cmd_mem.c,v retrieving revision 1.19 diff -u -r1.19 cmd_mem.c --- common/cmd_mem.c 10 Oct 2004 23:27:33 -0000 1.19 +++ common/cmd_mem.c 29 Nov 2004 15:14:40 -0000 @@ -646,8 +646,8 @@ vu_long num_words; #if defined(CFG_MEMTEST_SCRATCH) vu_long *dummy = (vu_long*)CFG_MEMTEST_SCRATCH; -#else - vu_long *dummy = NULL; +#else /* Undefined if address zero is writeable */ + vu_long *dummy = (vu_long*)0x00000000; #endif int j; int iterations = 1;