[AMD Official Use Only - General]
Validated on Phoenix and Raphael w/ IOMMU remapping mode, and found
random page fault when launching Xorg. I will debug this issue and
update the patch.
Best Regards,
Yifan
*From:* Deucher, Alexander <alexander.deuc...@amd.com>
*Sent:* Tuesday, August 29, 2023 2:06 AM
*To:* Koenig, Christian <christian.koe...@amd.com>; Zhang, Yifan
<yifan1.zh...@amd.com>; Christian König
<ckoenig.leichtzumer...@gmail.com>; amd-gfx@lists.freedesktop.org
*Subject:* Re: [PATCH v3 2/2] drm/amdgpu: Put page tables to GTT
memory for gfx10 onwards APUs
[AMD Official Use Only - General]
Technically the AMD IOMMU uses direct mapping mode for any device
which claims to support ATS in order to support the IOMMUv2
functionality, but that was also the case with Raven systems which
were problematic when remapping mode was enabled. That said, now that
IOMMUv2 support has been removed, there's no reason to use direct
mapping in the IOMMU driver so that may change.
Alex
------------------------------------------------------------------------
*From:*Koenig, Christian <christian.koe...@amd.com>
*Sent:* Monday, August 28, 2023 7:30 AM
*To:* Zhang, Yifan <yifan1.zh...@amd.com>; Christian König
<ckoenig.leichtzumer...@gmail.com>; amd-gfx@lists.freedesktop.org
<amd-gfx@lists.freedesktop.org>
*Cc:* Deucher, Alexander <alexander.deuc...@amd.com>
*Subject:* Re: [PATCH v3 2/2] drm/amdgpu: Put page tables to GTT
memory for gfx10 onwards APUs
Well, there seems to be a very basic misunderstood here: The IOMMU
isolation level is *not* ASIC dependent!
Try to set amd_iommu=force_isolation on the kernel command line.
This is a configuration option customers can use to harden their systems
and when this isn't properly tested we can't allow page tables in system
memory.
Regards,
Christian.
Am 28.08.23 um 13:23 schrieb Zhang, Yifan:
> [Public]
>
> Not yet. It will be only enabled for gfx10.3.3 and later APU
initially, IOMMU is pass through in these ASIC.
>
> -----Original Message-----
> From: Christian König <ckoenig.leichtzumer...@gmail.com>
> Sent: Monday, August 28, 2023 5:41 PM
> To: Zhang, Yifan <yifan1.zh...@amd.com>; amd-gfx@lists.freedesktop.org
> Cc: Deucher, Alexander <alexander.deuc...@amd.com>; Koenig,
Christian <christian.koe...@amd.com>
> Subject: Re: [PATCH v3 2/2] drm/amdgpu: Put page tables to GTT
memory for gfx10 onwards APUs
>
> Is that now validated with IOMMU in non pass through mode?
>
> Christian.
>
> Am 28.08.23 um 10:58 schrieb Zhang, Yifan:
>> [AMD Official Use Only - General]
>>
>> Ping
>>
>> -----Original Message-----
>> From: Zhang, Yifan <yifan1.zh...@amd.com>
>> Sent: Friday, August 25, 2023 8:34 AM
>> To: amd-gfx@lists.freedesktop.org
>> Cc: Deucher, Alexander <alexander.deuc...@amd.com>; Koenig,
Christian <christian.koe...@amd.com>; Zhang, Yifan <yifan1.zh...@amd.com>
>> Subject: [PATCH v3 2/2] drm/amdgpu: Put page tables to GTT memory
for gfx10 onwards APUs
>>
>> To decrease VRAM pressure for APUs, put page tables to GTT domain
for gfx10 and newer APUs.
>>
>> v2: only enable it for gfx10 and newer APUs (Alex, Christian)
>>
>> Signed-off-by: Yifan Zhang <yifan1.zh...@amd.com>
>> ---
>> drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c | 9 ++++++---
>> 1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
>> index 96d601e209b8..4603d87c61a0 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
>> @@ -515,10 +515,13 @@ int amdgpu_vm_pt_create(struct amdgpu_device
*adev, struct amdgpu_vm *vm,
>> bp.size = amdgpu_vm_pt_size(adev, level);
>> bp.byte_align = AMDGPU_GPU_PAGE_SIZE;
>>
>> - if (!adev->gmc.is_app_apu)
>> - bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
>> - else
>> + if (adev->gmc.is_app_apu ||
>> + ((adev->flags & AMD_IS_APU) &&
>> + (adev->ip_versions[GC_HWIP][0] >= IP_VERSION(10, 3, 3))))
>> bp.domain = AMDGPU_GEM_DOMAIN_GTT;
>> + else
>> + bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
>> +
>>
>> bp.domain = amdgpu_bo_get_preferred_domain(adev, bp.domain);
>> bp.flags = AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS |
>> --
>> 2.37.3
>>
