I'm having a problem with flashrom V0.9.7.  I was following instructions that used v0.9.3 to update the bios on a ReadyNAS Pro6, which apparently worked:
 
# /opt/biosflash/flashrom -c W25x80 -w /opt/biosflash/RN_NV6_072610.ROM
flashrom v0.9.3-r1205 on Linux 3.7.5-1.el6.elrepo.x86_64 (x86_64), built with libpci 2.2.4-pre4, GCC 4.1.2 20061115 (prerelease) (Debian 4.1.1-21), little endian
flashrom is free software, get the source code at http://www.flashrom.org
 
Calibrating delay loop... OK.
No coreboot table found.
Found chipset "Intel ICH8/ICH8R", enabling flash write... OK.
This chipset supports the following protocols: FWH,SPI.
Found chip "Winbond W25x80" (1024 KB, SPI) at physical address 0xfff00000.
Flash image seems to be a legacy BIOS. Disabling checks.
Writing flash chip... Erasing flash before programming... Erasing flash chip... SUCCESS.
done.
Programming flash... done.
COMPLETE.
Verifying flash... VERIFIED.
 
But v0.9.7 requires configuration first, which fails, even though it finds both the chipset and the BIOS chip.  This is also under a later Debian release, if that matters.  The key to the problem seems to be "/dev/mem mmap failed: Resource temporarily unavailable".  But I am logged in as root and /dev/mem has the proper permissions:
     crw-r-----  1 root kmem      1,   1 Nov 28 23:23 mem
 
I have verified this response on two identical configurations, but I also have a different model ReadyNAS with the same Debian configuration and it works fine there.
 
Here is the whole dump of the response:
 
root@NASPro2:/data/Documents/BIOS# flashrom --programmer internal
flashrom v0.9.7-r1782 on Linux 4.1.30.x86_64.1 (x86_64)
flashrom is free software, get the source code at http://www.flashrom.org
 
Calibrating delay loop... OK.
Found chipset "Intel ICH8/ICH8R". Enabling flash write... BBAR offset is unknown on ICH8!
OK.
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1080000 bytes at 0x00000000fef80000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x1000000 bytes at 0x00000000ff000000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Found Winbond flash chip "W25X80" (1024 kB, SPI) at physical address 0xfff00000.
Error accessing flash chip, 0x800000 bytes at 0x00000000ff800000
/dev/mem mmap failed: Resource temporarily unavailable
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
Trying to unmap a nonexisting mapping!
Please report a bug at flashrom@flashrom.org
No operations were specified.
root@NASPro2:/data/Documents/BIOS#