On 07/02/2023 15:20, Alex Deucher wrote:
On Tue, Feb 7, 2023 at 9:19 AM Christian König <christian.koenig@xxxxxxx> wrote:
Am 07.02.23 um 15:17 schrieb Alex Deucher:
On Tue, Feb 7, 2023 at 9:11 AM Christian König
<ckoenig.leichtzumerken@xxxxxxxxx> wrote:
Am 07.02.23 um 15:07 schrieb Alex Deucher:
On Tue, Feb 7, 2023 at 2:38 AM Shashank Sharma <shashank.sharma@xxxxxxx> wrote:
On 07/02/2023 08:03, Christian König wrote:
Am 06.02.23 um 22:03 schrieb Alex Deucher:
On Mon, Feb 6, 2023 at 12:01 PM Christian König
<christian.koenig@xxxxxxx> wrote:
Am 06.02.23 um 17:56 schrieb Alex Deucher:
On Fri, Feb 3, 2023 at 5:26 PM Shashank Sharma
<shashank.sharma@xxxxxxx> wrote:
Hey Alex,
On 03/02/2023 23:07, Alex Deucher wrote:
On Fri, Feb 3, 2023 at 4:54 PM Shashank Sharma
<shashank.sharma@xxxxxxx> wrote:
From: Alex Deucher <alexander.deucher@xxxxxxx>
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@xxxxxxx>
Cc: Christian Koenig <christian.koenig@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Shashank Sharma <shashank.sharma@xxxxxxx>
---
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)
Doorbells on pre-vega hardware are 32 bits so that is where that comes
from, but from vega onward most doorbells are 64 bit. I think some
versions of VCN may still use 32 bit doorbells. Internally in the
kernel driver we just use two slots for newer hardware, but for the
UAPI, I think we can just stick with 64 bit slots to avoid confusion.
Even if an engine only uses a 32 bit one, I don't know that there is
much value to trying to support variable doorbell sizes.
I think we can stick with using __u32 because this is *not* the size of
the doorbell entries.
Instead this is the offset into the BO where to find the doorbell for
this queue (which then in turn is 64bits wide).
Since we will probably never have more than 4GiB doorbells we should be
pretty save to use 32bits here.
Yes, the offset would still be 32 bits, but the units would be
qwords. E.g.,
+ /** Doorbell offset in qwords */
+ __u32 doorbell_offset;
That way you couldn't accidently specify an overlapping doorbell.
Ah, so you only wanted to fix the comment. That was absolutely not
clear from the discussion.
If I understand this correctly, the offset of the doorbell in the BO is
still is 32-bit, but its width (size in bytes) is 64 bits. Am I getting
that right ?
Right. Each doorbell is 64 bits (8 bytes) so this value would
basically be an index into the doorbell bo. Having it be a 64 bit
index rather than a 32 bit index would avoid the possibility of users
specifying overlapping doorbells. E.g.,
offset in bytes
0 - doorbell
4 - doorbell
Would be incorrect, while
offset in bytes
0 - doorbell
8 - doorbell
Would be correct.
I.e., u64 doorbell_page[512] vs u32 doorbell_page[1024]
Well I usually prefer just straight byte offsets, but I think the main
question is what does the underlying hw/fw use?
If that's a dword index we should probably stick with that in the UAPI
as well. If it's in qword then stick to that, if it's in bytes than use
that.
The MQD takes a dword offset from the start of the BAR, but the
doorbell is 64 bits wide so we have to be careful that we check for
overlapping doorbells.
Well then let's just add an "if (doorbell_idx & 0x1) return -EINVAL;" to
the kernel instead.
That's far less confusing that having dword in the MQD and qword in the
UAPI.
Yes, agreed.
Got it, Thanks.
- Shashank
Alex
Christian.
Alex
Otherwise we will just confuse people when we convert between the
different API levels.
Christian.
Alex
- Shashank
Christian.
Alex
Christian.
Alex
+ /** 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
