[PATCH 1/6] drm/amdgpu: add CHIP_IP_DISCOVERY support for virtualization

[Chen, Horace]

[AMD Official Use Only - General]

Hi Alex,

By current design, we will keep this register same for all new asics.
Also, the amdgpu_detect_virtualization will be called before we read the IP discovery table (virtualization needs to send a message to host machine to request for the IP discovery table preparation). So we can't use any IP version to decide the register.

Regards,
Horace.

-----Original Message-----
From: Alex Deucher <alexdeucher at gmail.com>
Sent: Thursday, July 21, 2022 10:37 PM
To: Chen, Horace <Horace.Chen at amd.com>
Cc: amd-gfx at lists.freedesktop.org; Grodzovsky, Andrey <Andrey.Grodzovsky at amd.com>; Xiao, Jack <Jack.Xiao at amd.com>; Xu, Feifei <Feifei.Xu at amd.com>; Wang, Yang(Kevin) <KevinYang.Wang at amd.com>; Xiaojie Yuan <xiaojie.yuan at amd.com>; Tuikov, Luben <Luben.Tuikov at amd.com>; Deucher, Alexander <Alexander.Deucher at amd.com>; Quan, Evan <Evan.Quan at amd.com>; Koenig, Christian <Christian.Koenig at amd.com>; Liu, Monk <Monk.Liu at amd.com>; Zhang, Hawking <Hawking.Zhang at amd.com>
Subject: Re: [PATCH 1/6] drm/amdgpu: add CHIP_IP_DISCOVERY support for virtualization

On Thu, Jul 21, 2022 at 5:52 AM Horace Chen <horace.chen at amd.com> wrote:
>
> For further chips we will use CHIP_IP_DISCOVERY, so add this support
> for virtualization

All current and future chips will use CHIP_IP_DISCOVERY.  If we plan to keep the register the same for all new aics, this should be fine.
If we might need to have it per asic I think you might want something more like this:

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
index 9be57389301b..0bdd71f9a8fb 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
@@ -709,6 +709,16 @@ void amdgpu_detect_virtualization(struct
amdgpu_device *adev)
        case CHIP_ALDEBARAN:
                reg = RREG32(mmRCC_IOV_FUNC_IDENTIFIER);
                break;
+       case CHIP_IP_DISCOVERY:
+               switch (adev->ip_versions[GC_HWIP][0]) {
+               case IP_VERSION(11, 0, 0):
+                       reg = RREG32(mmRCC_IOV_FUNC_IDENTIFIER);
+                       break;
+               default:
+                       reg = 0;
+                       break;
+               }
+               break;
        default: /* other chip doesn't support SRIOV */
                reg = 0;
                break;

Alex

>
> Signed-off-by: Horace Chen <horace.chen at amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> index 7d7044e9de2f..ab55602ff534 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
> @@ -705,6 +705,7 @@ void amdgpu_detect_virtualization(struct amdgpu_device *adev)
>         case CHIP_SIENNA_CICHLID:
>         case CHIP_ARCTURUS:
>         case CHIP_ALDEBARAN:
> +       case CHIP_IP_DISCOVERY:
>                 reg = RREG32(mmRCC_IOV_FUNC_IDENTIFIER);
>                 break;
>         default: /* other chip doesn't support SRIOV */ @@ -748,6
> +749,7 @@ void amdgpu_detect_virtualization(struct amdgpu_device *adev)
>                 case CHIP_NAVI10:
>                 case CHIP_NAVI12:
>                 case CHIP_SIENNA_CICHLID:
> +               case CHIP_IP_DISCOVERY:
>                         nv_set_virt_ops(adev);
>                         /* try send GPU_INIT_DATA request to host */
>                         amdgpu_virt_request_init_data(adev);
> --
> 2.25.1
>