Raven: KFD/HSA depends on AMD_IOMMU_V2 (was: [PATCH 6/6] drm/amdkfd: Enable Raven for KFD)

[Alex Deucher]

On Mon, Jul 30, 2018 at 11:25 AM, Paul Menzel
<pmenzel+amd-gfx at molgen.mpg.de> wrote:
> Dear Oded,
>
>
> On 07/30/18 15:53, Oded Gabbay wrote:
>> Do you have IOMMUv2 enabled on this chipset?
>
> No, I did not. With `AMD_IOMMU_V2` selected, the device is found.
>
> ```
> $ grep AMD_IOMMU /boot/config-4.18.0-rc3-01368-gb5aa3f4aef72
> CONFIG_AMD_IOMMU=y
> CONFIG_AMD_IOMMU_V2=m
> $ sudo dmesg | grep -i kfd
> [sudo] password for paul:
> [   20.767499] calling  kfd_module_init+0x0/0x1000 [amdkfd] @ 365
> [   20.770567] kfd kfd: Initialized module
> [   20.771195] initcall kfd_module_init+0x0/0x1000 [amdkfd] returned 0 after 3598 usecs
> [   20.893432] Modules linked in: amdkfd amd_iommu_v2 snd_hda_codec_realtek crct10dif_pclmul crc32_pclmul snd_hda_codec_hdmi snd_hda_codec_generic ghash_clmulni_intel snd_hda_intel amdgpu(+) i2c_piix4 r8169 k10temp snd_hda_codec snd_hda_core mii snd_hwdep snd_pcm snd_timer snd chash soundcore gpu_sched wmi video crc32c_intel xhci_pci xhci_hcd
> [   20.948465] kfd kfd: Allocated 3969056 bytes on gart
> [   20.948663] kfd kfd: added device 1002:15dd
> ```
>
>> If not, amdkfd won't include raven support.
>
> Hmm, then the warning is very confusing. Also, shouldn’t the build
> system ensure that the dependencies are selected?

It's only required for APUs.  If you use a dGPU in a intel system for
example, you may not want the AMD IOMMU driver.

Alex