Switchable graphics. Find out which one is in use?

[DupermanDave]

I have a separate thread open regarding battery life, but I have this other off-topic question. My laptop has an ATI and intel card and I'd like to know how I can determine which graphics card is currently in use. I can run this command:

cat /sys/kernel/debug/vgaswitcheroo/switch

and it'll output

0:IGD:+:Pwr:0000:00:02.0                                                                                      
1:DIS: :Pwr:0000:01:00.0

How can I determine which one is intel and which one is ATI? I know how to turn off the unused card (echo OFF > /sys/kernel/debug/vgaswitcheroo/switch)

Also, can anyone tell me what IGD, DIS, DISS, and all of those other things mean?

[marko]

Originally Posted by DupermanDave

I have a separate thread open regarding battery life, but I have this other off-topic question. My laptop has an ATI and intel card and I'd like to know how I can determine which graphics card is currently in use. I can run this command:

cat /sys/kernel/debug/vgaswitcheroo/switch

and it'll output

0:IGD:+:Pwr:0000:00:02.0                                                                                      
1:DIS: :Pwr:0000:01:00.0

How can I determine which one is intel and which one is ATI? I know how to turn off the unused card (echo OFF > /sys/kernel/debug/vgaswitcheroo/switch)

Also, can anyone tell me what IGD, DIS, DISS, and all of those other things mean?

IGD = "Integrated" --> that's the Intel one (inside Ivy bridge or Sandy Bridge cpu, etc)
DIS = "Discrete" --> that's the ATI (here in this case) or Nvidia (on other laptops)

I think the "+" means which one is in use (the IGD/ Intel is used and the discrete ATI is not used) and the fact both lines
have "Pwr" means both cards are powered

You can also compare to the output from 'lspci -v'

# lspci -v | grep -A 11 VGA
00:02.0 VGA compatible controller: Intel Corporation Device 0166 (rev 09) (prog-if 00 [VGA controller])
Subsystem: Toshiba America Info Systems Device 0002
Flags: bus master, fast devsel, latency 0, IRQ 42
Memory at e0000000 (64-bit, non-prefetchable) [size=4M]
Memory at d0000000 (64-bit, prefetchable) [size=256M]
I/O ports at 2000 [size=64]
Expansion ROM at <unassigned> [disabled]
Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
Capabilities: [d0] Power Management version 2
Capabilities: [a4] PCI Advanced Features
Kernel driver in use: i915

I only have an Intel Ivy Bridge with no discrete card so I just have the "00:02.0" entry which is the Intel IGD (and I can't show you the switcharoo/switch file because my single VGA laptop doesn't have one)
But that shows where your "00:02.0" comes from in the end of each line in the switch file, it's the bus address to the VGA hardware. Intel is usually 00:02.0 and the Nvidia and ATI will be something else (01:00.0 for your ATI )

I don't know about the switcharoo usage on Fedora but I found this URL that at least explains how it's working in ubuntu, it might be similar in Fedora

https://help.ubuntu.com/community/HybridGraphics

there is this Fedora thread too:
http://forums.fedoraforum.org/showthread.php?t=277051

[DupermanDave]

Originally Posted by marko

IGD = "Integrated" --> that's the Intel one (inside Ivy bridge or Sandy Bridge cpu, etc)
DIS = "Discrete" --> that's the ATI (here in this case) or Nvidia (on other laptops)

I think the "+" means which one is in use (the IGD/ Intel is used and the discrete ATI is not used) and the fact both lines
have "Pwr" means both cards are powered

You can also compare to the output from 'lspci -v'

I only have an Intel Ivy Bridge with no discrete card so I just have the "00:02.0" entry which is the Intel IGD (and I can't show you the switcharoo/switch file because my single VGA laptop doesn't have one)
But that shows where your "00:02.0" comes from in the end of each line in the switch file, it's the bus address to the VGA hardware. Intel is usually 00:02.0 and the Nvidia and ATI will be something else (01:00.0 for your ATI )

I don't know about the switcharoo usage on Fedora but I found this URL that at least explains how it's working in ubuntu, it might be similar in Fedora

https://help.ubuntu.com/community/HybridGraphics

there is this Fedora thread too:
http://forums.fedoraforum.org/showthread.php?t=277051

Do you know how I would have linux switch from the intel card to ATI? I believe the command is: echo DDIS > /sys/kernel/debug/vgaswitcheroo/switch

And to complicate things, do you know how to have it disable the intel card and use ATI on boot? I'm assuming you need to use multiple commands to disable and switch cards, but I'm not 100% which ones to use.

-edit-
I think I'm wrong in the above question, but I read some more and found there's this command (hybridopts=ON,IGD,OFF) in the GRUB options to enable both GPUs, switches to the integrated GPU, and finally turns off the discrete GPU. How would I go about doing the reverse? I want to disable the integrated GPU, switch to the ATI GPU, and turn off the integrated GPU.

[marko]

Originally Posted by DupermanDave

Do you know how I would have linux switch from the intel card to ATI? I believe the command is: echo DDIS > /sys/kernel/debug/vgaswitcheroo/switch

And to complicate things, do you know how to have it disable the intel card and use ATI on boot? I'm assuming you need to use multiple commands to disable and switch cards, but I'm not 100% which ones to use.

Don't those two links in the previous post #2 answer those?

[DupermanDave]

Originally Posted by marko

Don't those two links in the previous post #2 answer those?

Sort of. I guess I'm just confused as there seems to be 2 ways of handling the switch. It can be done with the switch commands and then it appears to be able to be handled upon boot by GRUB.

[DupermanDave]

I still need some assistance with this. I have both cards enabled just so I can play around with it, but I can't figure out how to get linux to switch to the discreet ATI card and use that.

I've run this command

echo DDIS > /sys/kernel/debug/vgaswitcheroo/switch

which is supposed to switch to the ATI card after logging out and then back in, but once I log out, X fails to start and I have to reboot where it then goes back into the intel card.

I might need to start a new thread, but basically I'm needing help 1) switching to the ATI card and disabling the intel card, and 2) installing the ATI drivers so I can start X.