BIOS flash write doesn't seem to work on Elite eval board

[peterfox9]

Posted on November 05, 2003 at 11:03

BIOS flash write doesn't seem to work on Elite eval board

[peterfox9]

Posted on November 05, 2003 at 07:43

I'm having trouble writing to the BIOS flash on the development board.

I use mio m8 ffff0000 0 but don't see any write strobes on the Bios flash device. Even after using mio dx8 22 51 4 to enable ROM writes, mio m8 ffff0000 0 doesn't result in any write strobes. Reading the bios works fine. This is on the Elite development board, running linux (Redhat 7.1). Have I missed something ? Replying to myself - yes ! I've modified the linuxbios flash_rom program to continuously do the flash ident accesses. This is write, write, write, read, read, write in a loop. MEMWR is busy with no gaps, MEMRD has nothing (except for the refresh cycles). Perhaps it is a shadowing problem ?[ This message was edited by: pjhf on 05-11-2003 12:46 ]

[peterfox9]

Posted on November 05, 2003 at 11:03

It's a bug in the freebios code I was using to access the flash.

A missing volatile allowed the C compiler to reorder the flash accesses so that the ident wasn't read properly.