Re: [PATCH V1] accel/amdxdna: Block running when IOMMU is off

[Mario Limonciello <mario.limonciello@amd.com>]

On 5/20/26 22:43, Lizhi Hou wrote:
> 
> On 5/20/26 17:57, Mario Limonciello wrote:
>>
>>
>> On 5/20/26 17:35, Lizhi Hou wrote:
>>> The AIE2 device firmware requires IOMMU on.
>>>
>>> Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/5319
>>> Signed-off-by: Lizhi Hou <lizhi.hou@amd.com>
>>> ---
>>>   drivers/accel/amdxdna/aie2_pci.c | 5 +++++
>>>   1 file changed, 5 insertions(+)
>>>
>>> diff --git a/drivers/accel/amdxdna/aie2_pci.c b/drivers/accel/ 
>>> amdxdna/aie2_pci.c
>>> index c4d345d4c76b..22f66c7f534d 100644
>>> --- a/drivers/accel/amdxdna/aie2_pci.c
>>> +++ b/drivers/accel/amdxdna/aie2_pci.c
>>> @@ -490,6 +490,11 @@ static int aie2_init(struct amdxdna_dev *xdna)
>>>           return -EINVAL;
>>>       }
>>>   +    if (!xdna->group) {
>>> +        XDNA_ERR(xdna, "Running without IOMMU not supported");
>>> +        return -EINVAL;
>>> +    }
>>> +
>>>       ndev = drmm_kzalloc(&xdna->ddev, sizeof(*ndev), GFP_KERNEL);
>>>       if (!ndev)
>>>           return -ENOMEM;
>>
>> I think it would be better to change the return for amdxdna_iommu_init().
> 
> amdxdna_iommu_init() is common code for all kinds of hardware. I would 
> keep the check only for AIE2 now, which is known to require IOMMU on.
Got it.  Then this makes sense.

Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
> 
> 
> Lizhi
> 
>>
>> This has a check that lets !xdna->group pass; which can be turned into 
>> an error code instead.