This is the mail archive of the ecos-discuss@sources.redhat.com mailing list for the eCos project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]

Re: What's the definition of VROM memory region used for?



How this mapping is implemented? MMU? I've seen some macros in the flash.c
files (FLASH_P2V) but honestly I'm still confused on how this mappping
happens...

Cristiano.

------------------------------------------------------------
Cristiano Ligieri Pereira - http://www.ics.uci.edu/~cpereira

On Thu, 2 Aug 2001, Mark Salter wrote:

> >>>>> Cristiano Ligieri Pereira writes:
> 
> > I've seen it in the XScale IQ80310 port and couldn't figure out what's
> > the purpose of it.
> 
> > Some clarification is appreciated.
> 
> Its part of the trickery with fixed_vectors on the IQ80310. Flash is at
> address zero, but that is where the CPU looks for exception vectors and
> where the arm hal expects the exception vectors to be. VROM is the 4K
> page which maps virtual address zero (where the vectors need to be) to 
> RAM so that the vectors are writable.
> 
> --Mark
> 


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]