Comme=
nt # 15
on bug 10066=
6
from Alex Deucher
(In reply to Luke McKee from comment #14)
> Alex thanks for your help.
>=20
> How it gets the rom is probably the same as this shell script using th=
e pci
> method listed on that github link in the last comment.
>=20
> # To read ROM you first need to write `1` to it, then read it, and the=
n write
> # `0` to it as described in the documentation. The reason is that the =
content
> # is not provided by default, by writing `1` to it you are telling the=
driver
> # to make it accessible.
> CARD_ID=3D0
> CARD_ROM=3D"/sys/class/drm/card${CARD_ID}/device/rom"
> FILE_ROM=3D"amdgpu-rom.bin"
>=20
> echo 1 > $CARD_ROM
> cat $CARD_ROM > $FILE_ROM
> echo 0 > $CARD_ROM
> echo "Saved as ${FILE_ROM}"
>=20
> --
> output:
> cat: /sys/class/drm/card0/device/rom: Input/output error
> [Not] Saved as amdgpu-rom.bin
That should generally work for desktop discrete cards. You need to be root
however.
>=20
> Is there any other user-space accessible methods to extract / write th=
e rom
> in Linux? Now only focusing on comparing the pp table to other roms not
> modifying it.
You can read the amdgpu_vbios file in debugfs. That will dump the copy of =
the
vbios that the driver is using.
> Maybe the powerplay is an atom-bios issue perhap=
s. If it's still broken in
> this 4.16-rc1 version I'm trying out now I'll open a ticket.
>=20
> For your reference this is the ticket that claims powerplay dpm is fix=
ed in
> newer kernels / dc=3D1 in 4.15.
> https://bugs.freedesktop.org/show_=
bug.cgi?id=3D100443#c37
There's no confirmation that specifically enabling dc fixed it.
Anyway, we are cluttering up this bug with potentially unrelated informatio=
n.=20
Please file a new bug for your issue and we can discuss it there.