On 16-Jul-26 4:25 AM, Timur Kristóf wrote:
On Tuesday, July 7, 2026 10:25:09 AM Central European Summer Time Lazar, Lijo
wrote:
On 04-Jul-26 12:20 AM, Timur Kristóf wrote:
On 2026. július 3., péntek 20:11:59 közép-európai nyári idő Joshi, Mukul
wrote:
I still haven't found any explanation why we use a doorbell for the CAM
in
the first
place? Lijo, Alex, Felix does anybody know that?
If I remember correctly, we weren't sure if the IH_RETRY_CAM_ACK register
would be available under
virtualization. And we were sure doorbells would
work for both bare-metal and virtualization.
Hi Mukul,
Can you clarify that please?
How are retry faults supposed to work under virtualization? Is the
interrupt processed by the guest or the host? Why is the IH_RETRY_CAM_ACK
register not available under virtualization?
For clarification - CAM entries are separate for PF/VF. ACK register
also has PF/VF copies. However, in general host driver imposes MMIO
register access restrictions to VF, possibly that's the reason.
Please note that IH_RETRY_INT_CAM_CNTL is PF only. With new versions,
please make sure to add a VF check for programming.
Hi Lijo,
Can you please clarify what PF and VF means here?
PF = physical function. VF = virtual function. On virtualization
environments amdgpu is a guest driver.
Translates to below check for cam_cntl register programming.
if (!amdgpu_sriov_vf(adev))
Thanks,
Lijo
I'm not familiar with those abbreviations.
Thanks,
Timur
