Rajat Jain wrote:
On 8/31/05, chuck gelm <[EMAIL PROTECTED]> wrote:
Rajat Jain wrote:
Hi List,
I want to change the PCI Configuration space of a particular device in
my system. I am trying to use the "pcitweak" utility to do so, but am
not suceeding. I would appreciate if some body could provide me any
pointers in how to do so.
In this case, I want to change the value at offset 64:
$ pcitweak -r 5:9:1 64
0x01000001 //original value
$ pcitweak -w 5:9:1 64 0x02000002 //new value
$ pcitweak -r 5:9:1 64
0x01000001 //no change?
TIA,
Rajat Jain
Dear Rajat Jain:
'man pcitweak' indicates that it requires root privileges.
the '$' prompt in your console indicates 'user' privileges.
My 'root' prompt is a '#'.
I suggest that you do not have 'root' privileges when
executing a '-w' (write) command.
HTH, Chuck
"Pcitweak is a utility that can be used to examine or
change registers in the PCI configuration space. On most
platfoms pcitweak can only be run by the root user."
Un ... I'm sorry ... I put that "$" prompt manually here in this mail.
I AM the root and working on the "#" prompt. I would appreciate if
somebody can tell me any other commands than "pcitweak" and "setpci"
to change PCI configuration space.
Thanks & Regards,
Rajat Jain
Hi, Rajat Jain:
Sorry, I cannot help. Just for fun, I used pcitweak, scanpci, lspci,
and 'cat /proc/pci' and looked at my two rtl8139 ethernet cards. I
think I found that they have 256 bytes of memory; one card uses memory
0x3e014000 - 0x3e140ff or 0x100 bytes.
(cat /proc/pci |grep -A 1 -B 4 ealtek)
pcitweak read 32 bits (4 bytes) so
pcitweak 0:9:0 -r 0
would show bytes offset 0, 1, 2, & 3.
pcitweak 0:9:0 -r[-w] 64 [value]
would read[write] bytes offset 64, 65, 66, 67
or 0x100, 0x101, 0x102, 0x103
which is undefined. There might be no RAM memory at byte offset 64.
I also used pcitweak 0:9:0 -r 4096, which I assume is outside the
configuration space of my pci device, but pcitweak dutifully displayed
output. :-|
Hopefully you are not writing to ROM. :-|
Good luck,
Chuck
-
To unsubscribe from this list: send the line "unsubscribe linux-newbie" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.linux-learn.org/faqs
