How about if I specify the following flags in my mmap routine just like what
the pgprot_noncached micro did.
pgprot_val(vma->vm_page_prot) &= ~_CACHE_MASK;
pgprot_val(vma->vm_page_prot) |= _CACHE_UNCACHED;
Will this have kernel make the mmap'd memory non-cacheable? Or is there a mmap
non-cacheable patch?
Thanks in advance!
Teresa
-----Original Message-----
From: Jun Sun [mailto:jsun@mvista.com]
Sent: Friday, July 25, 2003 3:02 PM
To: Teresa Tao
Cc: linux-mips@linux-mips.org; jsun@mvista.com
Subject: Re: mmap'ed memory cacheable or uncheable
On Thu, Jul 24, 2003 at 08:26:59PM -0700, Teresa Tao wrote:
> Hi there,
>
> I got a question regarding the mmap'ed memory. Is the mmap'ed memory
> cacheable or uncheable? My driver just use the remap_page_range to map a
> reserved physical memory.
>
I am pretty much sure it is cached, although I can't pin down exactly
where in the mm subsystem it does so - I have had cache bugs related
to mmap().
Jun
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