Mohamed Ahmed
2025-Oct-06 19:13 UTC
[PATCH 4/5] drm/nouveau/mmu/tu102: Add support for compressed kinds
From: Ben Skeggs <bskeggs at nvidia.com>
Allow compressed PTE kinds to be written into PTEs when GSP-RM is
present, rather than reverting to their non-compressed versions.
Signed-off-by: Ben Skeggs <bskeggs at nvidia.com>
---
.../drm/nouveau/nvkm/subdev/mmu/vmmgp100.c | 46 ++++++++++++++++++-
1 file changed, 44 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgp100.c
b/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgp100.c
index ecff1096a1bb..ed15a4475181 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgp100.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgp100.c
@@ -109,12 +109,34 @@ gp100_vmm_pgt_pfn(struct nvkm_vmm *vmm, struct nvkm_mmu_pt
*pt,
nvkm_done(pt->memory);
}
+static inline u64
+gp100_vmm_comptag_nr(u64 size)
+{
+ return size >> 16; /* One comptag per 64KiB VRAM. */
+}
+
+static inline u64
+gp100_vmm_pte_comptagline_base(u64 addr)
+{
+ /* RM allocates enough comptags for all of VRAM, so use a 1:1 mapping. */
+ return (1 + gp100_vmm_comptag_nr(addr)) << 36; /*
NV_MMU_VER2_PTE_COMPTAGLINE */
+}
+
+static inline u64
+gp100_vmm_pte_comptagline_incr(u32 page_size)
+{
+ return gp100_vmm_comptag_nr(page_size) << 36; /*
NV_MMU_VER2_PTE_COMPTAGLINE */
+}
+
static inline void
gp100_vmm_pgt_pte(struct nvkm_vmm *vmm, struct nvkm_mmu_pt *pt,
u32 ptei, u32 ptes, struct nvkm_vmm_map *map, u64 addr)
{
u64 data = (addr >> 4) | map->type;
+ if (map->ctag)
+ data |= gp100_vmm_pte_comptagline_base(addr);
+
while (ptes--) {
VMM_WO064(pt, vmm, ptei++ * 8, data);
data += map->next;
@@ -195,6 +217,9 @@ gp100_vmm_pd0_pte(struct nvkm_vmm *vmm, struct nvkm_mmu_pt
*pt,
{
u64 data = (addr >> 4) | map->type;
+ if (map->ctag)
+ data |= gp100_vmm_pte_comptagline_base(addr);
+
while (ptes--) {
VMM_WO128(pt, vmm, ptei++ * 0x10, data, 0ULL);
data += map->next;
@@ -440,9 +465,26 @@ gp100_vmm_valid(struct nvkm_vmm *vmm, void *argv, u32 argc,
return -EINVAL;
}
+ /* Handle compression. */
if (kindm[kind] != kind) {
- /* Revert to non-compressed kind. */
- kind = kindm[kind];
+ struct nvkm_device *device = vmm->mmu->subdev.device;
+
+ /* Compression is only supported when using GSP-RM, as
+ * PMU firmware is required in order to initialise the
+ * compbit backing store.
+ */
+ if (nvkm_gsp_rm(device->gsp)) {
+ /* Turing GPUs require PTE_COMPTAGLINE to be filled,
+ * in addition to specifying a compressed kind.
+ */
+ if (device->card_type < GA100) {
+ map->ctag = gp100_vmm_pte_comptagline_incr(1 <<
map->page->shift);
+ map->next |= map->ctag;
+ }
+ } else {
+ /* Revert to non-compressed kind. */
+ kind = kindm[kind];
+ }
}
map->type |= BIT(0);
--
2.51.0