[PATCH v4 5/5] drm/xe: Make the PT code handle placement per PTE rather than per vma / range

[Lucas De Marchi]

On Wed, Mar 26, 2025 at 09:05:51AM +0100, Thomas Hellström wrote:
>diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
>index 9e719535a3bb..82ae159feed1 100644
>--- a/drivers/gpu/drm/xe/xe_pt.c
>+++ b/drivers/gpu/drm/xe/xe_pt.c
>@@ -278,13 +278,15 @@ struct xe_pt_stage_bind_walk {
> 	struct xe_vm *vm;
> 	/** @tile: The tile we're building for. */
> 	struct xe_tile *tile;
>-	/** @default_pte: PTE flag only template. No address is associated */
>-	u64 default_pte;
>+	/** @default_pte: PTE flag only template for VRAM. No address is associated */

		     ^
>+	u64 default_vram_pte;

		    ^

doc is wrong here. This would fix that for this patch:

// diff --git a/drivers/gpu/drm/xe/xe_pt.c b/drivers/gpu/drm/xe/xe_pt.c
// index 82ae159feed12..91ad347c8c7bf 100644
// --- a/drivers/gpu/drm/xe/xe_pt.c
// +++ b/drivers/gpu/drm/xe/xe_pt.c
// @@ -278,9 +278,9 @@ struct xe_pt_stage_bind_walk {
//         struct xe_vm *vm;
//         /** @tile: The tile we're building for. */
//         struct xe_tile *tile;
// -       /** @default_pte: PTE flag only template for VRAM. No address is associated */
// +       /** @default_vram_pte: PTE flag only template for VRAM. No address is associated */
//         u64 default_vram_pte;
// -       /** @default_pte: PTE flag only template for VRAM. No address is associated */
// +       /** @default_system_pte: PTE flag only template for system. No address is associated */
//         u64 default_system_pte;
//         /** @dma_offset: DMA offset to add to the PTE. */
//         u64 dma_offset;


However I was surprised that we didn't get any error in our CI.Hooks.


It looks like this entire struct is not in our docs at all:
https://docs.kernel.org/gpu/xe/xe_mm.html#pagetable-building

Should we add a

/**
  * struct xe_pt_stage_bind_walk - ...
  */

so it's visible? Or if it's internal detail from
drivers/gpu/drm/xe/xe_pt.c maybe we could drop the kernel-doc, leaving
them as "/*" comments instead?

Lucas De Marchi