Windows 10 Radeon Software vs. AMDGPU On Ubuntu Linux

[rabcor]

Double POst

[duby229]

You don't have to choose: there is x32, which is a calling convention running in long mode (64-bit) but with 4-byte pointers.

I thought only the kernel ran in long mode and then context switched to compatibility mode for 32bit code in userspace? If so then that 32bit code doesn't have access to additional registers or extensions. However if your right that long mode supports 2, 4 or 8 byte pointers, then in that case there is absolutely no reason to build a linux system that is totally 64bit since it will have access to all the additional registers and extensions from long mode..

EDIT: It should be pretty easy to write a tool to determine how much address space app needs and then compile it appropriately.

[duby229]

IGP is integrated, and DGP is discrete. I see this used on Arch and a couple other sites. I found it's a nice simple method to make it easier to remember the differance by simply changing the first letter.

Anyway, can anyone explain to be in lay how I make use, or force full-time if I have to, the DGP on my laptop instead of the IGP? Apparently the kernel is supposed to be 'intelligent', but it doesn't appear to happening with my one whole day of testing. Also, I'm on mesa and a Radeon 7670 on Arch (xorg is at 1.18, radeon at 7.7 and whatever comes after it, using all standard arch packages) so no AMDGPU for me (missed by one gen!). Apparently using radeon.modeset=1 doesn't do anything for this issue.

I think it's a drm feature called switcheroo. I've personally avoided laptops with both integrated and discrete graphics due to the number of complaints I've read about it.

Here is an Arch guide with all the info.

https://wiki.archlinux.org/index.php/hybrid_graphics

[bug77]

I thought only the kernel ran in long mode and then context switched to compatibility mode for 3bit code in userspace? If so then that 32bit code doesn't have access to additional registers or extensions. However if your right that long mode supports 2, 4 or 8 byte pointers, then in that case there is absolutely no reason to build a linux system that is totally 64bit since it will have access to all the additional registers and extensions from long mode..

EDIT: It should be pretty easy to write a tool to determine how much address space app needs and then compile it appropriately.

A compute intensive application would not necessarily need a ton of RAM, but it may still be faster with access to additional registers. But your trick will do for many apps.

I think it's a drm feature called switcheroo. I've personally avoided laptops with both integrated and discrete graphics due to the number of complaints I've read about it.

Here is an Arch guide with all the info.
https://wiki.archlinux.org/index.php/hybrid_graphics

Ha, I'm struggling to get my work laptop to use the discrete card right now. For some reason lspci says the nvidia card is using nouveau even if I manually removed nouveau from the system. So yeah, queue one more complaint about hybrid graphics.

[bridgman]

IGP is integrated, and DGP is discrete. I see this used on Arch and a couple other sites. I found it's a nice simple method to make it easier to remember the differance by simply changing the first letter.

Anyway, can anyone explain to be in lay how I make use, or force full-time if I have to, the DGP on my laptop instead of the IGP? Apparently the kernel is supposed to be 'intelligent', but it doesn't appear to happening with my one whole day of testing. Also, I'm on mesa and a Radeon 7670 on Arch (xorg is at 1.18, radeon at 7.7 and whatever comes after it, using all standard arch packages) so no AMDGPU for me (missed by one gen!). Apparently using radeon.modeset=1 doesn't do anything for this issue.

It's a userspace switch, not in the kernel. There are a few guides around depending on your distro (you mentioned Arch, is that what you are using ?), here's an example for Ubuntu:

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

[BenPope]

I was about to say "the preview driver is not tested on 16.04" but then I noticed Michael had successfully run it on 16.04 for this article

I'm using Ubuntu 15.10, but I don't think that makes a difference, I just built this: https://cgit.freedesktop.org/~agd5f/linux/tree/?h=drm-next-4.7-wip-polaris rebooted and then reinstalled the beta driver. Whilst installing the driver, the kernel module failed to build. Seems to work fine with the amdgpu driver in the kernel: http://openbenchmarking.org/result/1604191-HA-BPPADOKAN42.

I'm guessing as long as the kernel branch has the DAL stuff (and its API isn't changed significantly), the kernel amdgpu driver should work with the rest of the amdgpu pro stack, right?

[Adarion]

My sincere gratulation to the AMD-ATI team! This is impressive!
AMDGPU Pro most of the time on par with W10 or even in the lead. And the free stack also delivered a very good match.
Compare that to the situation ~8 years ago. Day and Night.

[bridgman]

I'm guessing as long as the kernel branch has the DAL stuff (and its API isn't changed significantly), the kernel amdgpu driver should work with the rest of the amdgpu pro stack, right?[/SIZE][/FONT][/COLOR]

Installing the amdgpu hybrid stack actually replaces the existing amdgpu kernel module with a new one built from a DKMS package, so the existing kernel amdgpu driver itself shouldn't matter much.

[stiiixy]

I thought only the kernel ran in long mode and then context switched to compatibility mode for 32bit code in userspace? If so then that 32bit code doesn't have access to additional registers or extensions. However if your right that long mode supports 2, 4 or 8 byte pointers, then in that case there is absolutely no reason to build a linux system that is totally 64bit since it will have access to all the additional registers and extensions from long mode..

EDIT: It should be pretty easy to write a tool to determine how much address space app needs and then compile it appropriately.

Thanks mate (and bridgman), I didn't realise there was actually another way to go about it in ARCH called PRIME,and I've been plugging away at that when I can. Very hackish methods all these things to get a game running, but at least with PRIME, I can simply specify

xrandr --setprovideroffloadsink provider sink

with provider being my DGP (0x55) and sink being IGP (0x7e) in my case.

Then run DRI_PRIME=1 ./nameof3Dapp (or just add DRI_PRIME=1 to the config/shortcut etc).

But then I run in to the black screen issue mentioned in th article, and currently installing MATE to see if it works better 'natively' compared to Plasma.

[liam]

What is IGP?

Integrated Graphics Processor