[PATCH 1/8] drm/amdgpu: UAPI for user queue management

[Shashank Sharma]

Hey Alex,

On 03/02/2023 23:07, Alex Deucher wrote:
> On Fri, Feb 3, 2023 at 4:54 PM Shashank Sharma <shashank.sharma at amd.com> wrote:
>> From: Alex Deucher <alexander.deucher at amd.com>
>>
>> This patch intorduces new UAPI/IOCTL for usermode graphics
>> queue. The userspace app will fill this structure and request
>> the graphics driver to add a graphics work queue for it. The
>> output of this UAPI is a queue id.
>>
>> This UAPI maps the queue into GPU, so the graphics app can start
>> submitting work to the queue as soon as the call returns.
>>
>> Cc: Alex Deucher <alexander.deucher at amd.com>
>> Cc: Christian Koenig <christian.koenig at amd.com>
>> Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
>> Signed-off-by: Shashank Sharma <shashank.sharma at amd.com>
>> ---
>>   include/uapi/drm/amdgpu_drm.h | 53 +++++++++++++++++++++++++++++++++++
>>   1 file changed, 53 insertions(+)
>>
>> diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
>> index 4038abe8505a..6c5235d107b3 100644
>> --- a/include/uapi/drm/amdgpu_drm.h
>> +++ b/include/uapi/drm/amdgpu_drm.h
>> @@ -54,6 +54,7 @@ extern "C" {
>>   #define DRM_AMDGPU_VM                  0x13
>>   #define DRM_AMDGPU_FENCE_TO_HANDLE     0x14
>>   #define DRM_AMDGPU_SCHED               0x15
>> +#define DRM_AMDGPU_USERQ               0x16
>>
>>   #define DRM_IOCTL_AMDGPU_GEM_CREATE    DRM_IOWR(DRM_COMMAND_BASE + DRM_AMDGPU_GEM_CREATE, union drm_amdgpu_gem_create)
>>   #define DRM_IOCTL_AMDGPU_GEM_MMAP      DRM_IOWR(DRM_COMMAND_BASE + DRM_AMDGPU_GEM_MMAP, union drm_amdgpu_gem_mmap)
>> @@ -71,6 +72,7 @@ extern "C" {
>>   #define DRM_IOCTL_AMDGPU_VM            DRM_IOWR(DRM_COMMAND_BASE + DRM_AMDGPU_VM, union drm_amdgpu_vm)
>>   #define DRM_IOCTL_AMDGPU_FENCE_TO_HANDLE DRM_IOWR(DRM_COMMAND_BASE + DRM_AMDGPU_FENCE_TO_HANDLE, union drm_amdgpu_fence_to_handle)
>>   #define DRM_IOCTL_AMDGPU_SCHED         DRM_IOW(DRM_COMMAND_BASE + DRM_AMDGPU_SCHED, union drm_amdgpu_sched)
>> +#define DRM_IOCTL_AMDGPU_USERQ         DRM_IOW(DRM_COMMAND_BASE + DRM_AMDGPU_USERQ, union drm_amdgpu_userq)
>>
>>   /**
>>    * DOC: memory domains
>> @@ -302,6 +304,57 @@ union drm_amdgpu_ctx {
>>          union drm_amdgpu_ctx_out out;
>>   };
>>
>> +/* user queue IOCTL */
>> +#define AMDGPU_USERQ_OP_CREATE 1
>> +#define AMDGPU_USERQ_OP_FREE   2
>> +
>> +#define AMDGPU_USERQ_MQD_FLAGS_SECURE  (1 << 0)
>> +#define AMDGPU_USERQ_MQD_FLAGS_AQL     (1 << 1)
>> +
>> +struct drm_amdgpu_userq_mqd {
>> +       /** Flags: AMDGPU_USERQ_MQD_FLAGS_* */
>> +       __u32   flags;
>> +       /** IP type: AMDGPU_HW_IP_* */
>> +       __u32   ip_type;
>> +       /** GEM object handle */
>> +       __u32   doorbell_handle;
>> +       /** Doorbell offset in dwords */
>> +       __u32   doorbell_offset;
> Since doorbells are 64 bit, maybe this offset should be in qwords.

Can you please help to cross check this information ? All the existing 
kernel doorbell calculations are keeping doorbells size as sizeof(u32)

>
>> +       /** GPU virtual address of the queue */
>> +       __u64   queue_va;
>> +       /** Size of the queue in bytes */
>> +       __u64   queue_size;
>> +       /** GPU virtual address of the rptr */
>> +       __u64   rptr_va;
>> +       /** GPU virtual address of the wptr */
>> +       __u64   wptr_va;
>> +};
>> +
>> +struct drm_amdgpu_userq_in {
>> +       /** AMDGPU_USERQ_OP_* */
>> +       __u32   op;
>> +       /** Flags */
>> +       __u32   flags;
>> +       /** Queue handle to associate the queue free call with,
>> +        * unused for queue create calls */
>> +       __u32   queue_id;
>> +       __u32   pad;
>> +       /** Queue descriptor */
>> +       struct drm_amdgpu_userq_mqd mqd;
>> +};
>> +
>> +struct drm_amdgpu_userq_out {
>> +       /** Queue handle */
>> +       __u32   q_id;
> Maybe this should be queue_id to match the input.

Agree.

- Shashank

> Alex
>
>> +       /** Flags */
>> +       __u32   flags;
>> +};
>> +
>> +union drm_amdgpu_userq {
>> +       struct drm_amdgpu_userq_in in;
>> +       struct drm_amdgpu_userq_out out;
>> +};
>> +
>>   /* vm ioctl */
>>   #define AMDGPU_VM_OP_RESERVE_VMID      1
>>   #define AMDGPU_VM_OP_UNRESERVE_VMID    2
>> --
>> 2.34.1
>>