Problem trying to address custom hardware

Matt Porter mporter at
Thu Aug 26 03:40:59 EST 2004

[your mailer is really bad and should be fixed, this required heavy editing]

On Tue, Aug 24, 2004 at 04:10:15PM -0700, Oliver King-Smith wrote:
> memfd = open("/dev/mem", O_RDWR);
> if (memfd){
>  pCPLD = (CPLD_REGISTERS *) mmap(0,
>  memfd, CPLD_OFFSET);

Others addressed your core problem, but you should know that this
mmap request won't produce the desired result. You need MAP_SHARED
since MAP_PRIVATE will result in a COW when you attempt to modify
your register.


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