AMDGPU vs. Radeon DRM With Linux 4.14 On GCN 1.0/SI GPUs

[darkbasic]

so once 4.15 lands it will be better to use amdgpu for everything (it isn't now due to no hdmi audio...)

There will be no DC/DAL for HD 7950, ever. Only newer cards will be supported.

[Strunkenbold]

Ive made the switch with my 7970 two months ago and performance advantage was at least 5%. Since they got HDMI audio working, the switch is actually a no brainer and most SI users will benefit. Very good work AMD!

[humbug]

My R9 290 is back to being broken/regressed on Radeon DRM and only performs correctly on AMDGPU.

Yep in general gcn 1.1 is just more reliable overall under amdgpu. I think they should have made it the default already.

Hope you will include the r9 290 numbers anyway for amdgpu... Even if there is no radeon drm to compare.

[varikonniemi]

Overclocking seems to be broken on amdgpu gcn1, even as root it does not change the value nor clock. Also the opencl stack reports 14 compute units when it has 28. I wonder if this ever gets working or is it lost to legacy status.

[Khudsa]

Not sure about gcn 1.0 which this article is about.

but gcn 1.1 actually works a lot better under the new amdgpu kernel driver in my experience with my r9 290. It solved random issues for me such as no display on certain monitors, and extreme low performance due to reclocking not working under certain kernel versions...

That's just from a reliability/stability perspective without even talking about features and performance. Plus the benefits of getting as many supported users as possible off of the legacy driver.

How do you use amdgpu on an r9 290 card? With my r9 290 card I'm unable to run it. Append "amdgpu.cik_support=1 radeon.cik_support=0" to grub, blacklisting radeon and modprobe amdgpu, nothing work and it reverts to soft acceleration.

Thx.

[frosth]

Khudsa, what distro?
and try:

zcat /proc/config.gz | grep AMDGPU_CIK

if it gives

CONFIG_DRM_AMDGPU_CIK=y

R9 290/390 should works with amdgpu (for kernel side)


BTW. It's nothing new for tahiti but there are very good results for pitcairn. All regressions are gone and opengl is even better now on new driver.I don't have GCN1 anymore but still it's very impressive.

[Khudsa]

Khudsa, what distro?
and try:

zcat /proc/config.gz | grep AMDGPU_CIK

if it gives

CONFIG_DRM_AMDGPU_CIK=y

R9 290/390 should works with amdgpu (for kernel side)


BTW. It's nothing new for tahiti but there are very good results for pitcairn. All regressions are gone and opengl is even better now on new driver.I don't have GCN1 anymore but still it's very impressive.

It sound really cool. I'm running Debian SID. I don't have that config.gz, I'll investigate more. Thanks!

[Veerappan]

so once 4.15 lands it will be better to use amdgpu for everything (it isn't now due to no hdmi audio...)

i had been using amdgpu on my radeon 7850 (Pitcairn, gcn 1.0), and it had a habit of hanging my system every few days, where the radeon module is rock solid. This is on 4.13, maybe 4.14rc and 4.15 will be better. Otherwise, once uvd is ready, I'd agree that I'd be ready to switch over