Re: [coreboot] flashrom: Can't mmap memory

[Myles Watson]

On Fri, Feb 6, 2009 at 10:19 AM, Myles Watson  wrote:
> On Thu, Feb 5, 2009 at 8:18 PM, Myles Watson  wrote:
> > > -----Original Message-----
> > > From: Carl-Daniel Hailfinger [mailto:[e-mail]]
> > > Sent: Thursday, February 05, 2009 4:19 PM
> > > To: Myles Watson
> > > Cc: Coreboot
> > > Subject: Re: [coreboot] flashrom: Can't mmap memory
> > >
> > > On 05.02.2009 21:26, Myles Watson wrote:
> > > > When I boot using the factory BIOS on my s2895 flashrom works.  When I
> > > > boot with Coreboot, I get the Error:
> > > >
> > > > Can't mmap memory using /dev/mem: Operation not permitted
> > > >
> > > > It shouldn't be kernel parameters since I'm using the same grub2 entry
> > > > to boot either way.
> > > >
> > > > This sounds a little too familiar, but I can't find a thread where
> > > > this isn't linked to a newer, more restrictive kernel.
> > >
> > > Could be the memory map passed by cbtable or e820. A diff between dmesg
> > > for each configuration would probably reveal quite a bit of info.
> >
> > Good idea.  Tomorrow I'll look at that.  The memory maps are quite
> > different, but in both cases the ROM is marked uncacheable.
>
> It turns out that flashrom is getting confused and trying to map
> 0xfff00000-0x10100000.  The factory BIOS doesn't boost memory up
> there, so it was fine.  If I specify the chip with -c SST49LF080A it
> succeeds.  I don't know why the size is different depending on whether
> you specify the chip or not.
>
> An added printf shows that flash->total_size = 0x800 when it fails,
> and 0x400 when it succeeds.

I should have used flashrom -V earlier.  Here it is:

Probing for SST SST49LF040, 512 KB: probe_jedec: id1 0xbf, id2 0x5b
Probing for SST SST49LF040B, 512 KB: probe_jedec: id1 0xbf, id2 0x5b
Probing for SST SST49LF080A, 1024 KB: probe_jedec: id1 0xbf, id2 0x5b
Found chip "SST SST49LF080A" (1024 KB) at physical address 0xfff00000.
Probing for SST SST49LF160C, 2048 KB: Error accessing flash chip,
0x200000 bytes at 0xfff00000
/dev/mem mmap failed: Operation not permitted

I don't know enough about flashrom to know if it should have stopped,
or if it should have figured out a better base address for the
SST49LF160C.

Hopefully that's enough information to point in the right direction.

Thanks,
Myles