drm/nouveau/mmu: implement new vmm backend

This is the common code to support a rework of the VMM backends.

It adds support for more than 2 levels of page table nesting, which
is required to be able to support GP100's MMU layout.

Sparse mappings (that don't cause MMU faults when accessed) are now
supported, where the backend provides it.

Dual-PT handling had to become more sophisticated to support sparse,
but this also allows us to support an optimisation the MMU provides
on GK104 and newer.

Certain operations can now be combined into a single page tree walk
to avoid some overhead, but also enables optimsations like skipping
PTE unmap writes when the PT will be destroyed anyway.

The old backend has been hacked up to forward requests onto the new
backend, if present, so that it's possible to bisect between issues
in the backend changes vs the upcoming frontend changes.

Until the new frontend has been merged, new backends will leak BAR2
page tables on module unload.  This is expected, and it's not worth
the effort of hacking around this as it doesn't effect runtime.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 580 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c b/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c
index 7e00b9adca05..46c7fecf0054 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmm.c
@@ -67,9 +67,559 @@ nvkm_vmm_pt_new(const struct nvkm_vmm_desc *desc, bool sparse,
 	return pgt;
 }
 
+struct nvkm_vmm_iter {
+	const struct nvkm_vmm_page *page;
+	const struct nvkm_vmm_desc *desc;
+	struct nvkm_vmm *vmm;
+	u64 cnt;
+	u16 max, lvl;
+	u32 pte[NVKM_VMM_LEVELS_MAX];
+	struct nvkm_vmm_pt *pt[NVKM_VMM_LEVELS_MAX];
+	int flush;
+};
+
+#ifdef CONFIG_NOUVEAU_DEBUG_MMU
+static const char *
+nvkm_vmm_desc_type(const struct nvkm_vmm_desc *desc)
+{
+	switch (desc->type) {
+	case PGD: return "PGD";
+	case PGT: return "PGT";
+	case SPT: return "SPT";
+	case LPT: return "LPT";
+	default:
+		return "UNKNOWN";
+	}
+}
+
+static void
+nvkm_vmm_trace(struct nvkm_vmm_iter *it, char *buf)
+{
+	int lvl;
+	for (lvl = it->max; lvl >= 0; lvl--) {
+		if (lvl >= it->lvl)
+			buf += sprintf(buf,  "%05x:", it->pte[lvl]);
+		else
+			buf += sprintf(buf, "xxxxx:");
+	}
+}
+
+#define TRA(i,f,a...) do {                                                     \
+	char _buf[NVKM_VMM_LEVELS_MAX * 7];                                    \
+	struct nvkm_vmm_iter *_it = (i);                                       \
+	nvkm_vmm_trace(_it, _buf);                                             \
+	VMM_TRACE(_it->vmm, "%s "f, _buf, ##a);                                \
+} while(0)
+#else
+#define TRA(i,f,a...)
+#endif
+
+static inline void
+nvkm_vmm_flush_mark(struct nvkm_vmm_iter *it)
+{
+	it->flush = min(it->flush, it->max - it->lvl);
+}
+
+static inline void
+nvkm_vmm_flush(struct nvkm_vmm_iter *it)
+{
+	if (it->flush != NVKM_VMM_LEVELS_MAX) {
+		if (it->vmm->func->flush) {
+			TRA(it, "flush: %d", it->flush);
+			it->vmm->func->flush(it->vmm, it->flush);
+		}
+		it->flush = NVKM_VMM_LEVELS_MAX;
+	}
+}
+
+static void
+nvkm_vmm_unref_pdes(struct nvkm_vmm_iter *it)
+{
+	const struct nvkm_vmm_desc *desc = it->desc;
+	const int type = desc[it->lvl].type == SPT;
+	struct nvkm_vmm_pt *pgd = it->pt[it->lvl + 1];
+	struct nvkm_vmm_pt *pgt = it->pt[it->lvl];
+	struct nvkm_mmu_pt *pt = pgt->pt[type];
+	struct nvkm_vmm *vmm = it->vmm;
+	u32 pdei = it->pte[it->lvl + 1];
+
+	/* Recurse up the tree, unreferencing/destroying unneeded PDs. */
+	it->lvl++;
+	if (--pgd->refs[0]) {
+		const struct nvkm_vmm_desc_func *func = desc[it->lvl].func;
+		/* PD has other valid PDEs, so we need a proper update. */
+		TRA(it, "PDE unmap %s", nvkm_vmm_desc_type(&desc[it->lvl - 1]));
+		pgt->pt[type] = NULL;
+		if (!pgt->refs[!type]) {
+			/* PDE no longer required. */
+			if (pgd->pt[0]) {
+				if (pgt->sparse) {
+					func->sparse(vmm, pgd->pt[0], pdei, 1);
+					pgd->pde[pdei] = NVKM_VMM_PDE_SPARSE;
+				} else {
+					func->unmap(vmm, pgd->pt[0], pdei, 1);
+					pgd->pde[pdei] = NULL;
+				}
+			} else {
+				/* Special handling for Tesla-class GPUs,
+				 * where there's no central PD, but each
+				 * instance has its own embedded PD.
+				 */
+				func->pde(vmm, pgd, pdei);
+				pgd->pde[pdei] = NULL;
+			}
+		} else {
+			/* PDE was pointing at dual-PTs and we're removing
+			 * one of them, leaving the other in place.
+			 */
+			func->pde(vmm, pgd, pdei);
+		}
+
+		/* GPU may have cached the PTs, flush before freeing. */
+		nvkm_vmm_flush_mark(it);
+		nvkm_vmm_flush(it);
+	} else {
+		/* PD has no valid PDEs left, so we can just destroy it. */
+		nvkm_vmm_unref_pdes(it);
+	}
+
+	/* Destroy PD/PT. */
+	TRA(it, "PDE free %s", nvkm_vmm_desc_type(&desc[it->lvl - 1]));
+	nvkm_mmu_ptc_put(vmm->mmu, vmm->bootstrapped, &pt);
+	if (!pgt->refs[!type])
+		nvkm_vmm_pt_del(&pgt);
+	it->lvl--;
+}
+
+static void
+nvkm_vmm_unref_sptes(struct nvkm_vmm_iter *it, struct nvkm_vmm_pt *pgt,
+		     const struct nvkm_vmm_desc *desc, u32 ptei, u32 ptes)
+{
+	const struct nvkm_vmm_desc *pair = it->page[-1].desc;
+	const u32 sptb = desc->bits - pair->bits;
+	const u32 sptn = 1 << sptb;
+	struct nvkm_vmm *vmm = it->vmm;
+	u32 spti = ptei & (sptn - 1), lpti, pteb;
+
+	/* Determine how many SPTEs are being touched under each LPTE,
+	 * and drop reference counts.
+	 */
+	for (lpti = ptei >> sptb; ptes; spti = 0, lpti++) {
+		const u32 pten = min(sptn - spti, ptes);
+		pgt->pte[lpti] -= pten;
+		ptes -= pten;
+	}
+
+	/* We're done here if there's no corresponding LPT. */
+	if (!pgt->refs[0])
+		return;
+
+	for (ptei = pteb = ptei >> sptb; ptei < lpti; pteb = ptei) {
+		/* Skip over any LPTEs that still have valid SPTEs. */
+		if (pgt->pte[pteb] & NVKM_VMM_PTE_SPTES) {
+			for (ptes = 1, ptei++; ptei < lpti; ptes++, ptei++) {
+				if (!(pgt->pte[ptei] & NVKM_VMM_PTE_SPTES))
+					break;
+			}
+			continue;
+		}
+
+		/* As there's no more non-UNMAPPED SPTEs left in the range
+		 * covered by a number of LPTEs, the LPTEs once again take
+		 * control over their address range.
+		 *
+		 * Determine how many LPTEs need to transition state.
+		 */
+		pgt->pte[ptei] &= ~NVKM_VMM_PTE_VALID;
+		for (ptes = 1, ptei++; ptei < lpti; ptes++, ptei++) {
+			if (pgt->pte[ptei] & NVKM_VMM_PTE_SPTES)
+				break;
+			pgt->pte[ptei] &= ~NVKM_VMM_PTE_VALID;
+		}
+
+		if (pgt->pte[pteb] & NVKM_VMM_PTE_SPARSE) {
+			TRA(it, "LPTE %05x: U -> S %d PTEs", pteb, ptes);
+			pair->func->sparse(vmm, pgt->pt[0], pteb, ptes);
+		} else
+		if (pair->func->invalid) {
+			/* If the MMU supports it, restore the LPTE to the
+			 * INVALID state to tell the MMU there is no point
+			 * trying to fetch the corresponding SPTEs.
+			 */
+			TRA(it, "LPTE %05x: U -> I %d PTEs", pteb, ptes);
+			pair->func->invalid(vmm, pgt->pt[0], pteb, ptes);
+		}
+	}
+}
+
+static bool
+nvkm_vmm_unref_ptes(struct nvkm_vmm_iter *it, u32 ptei, u32 ptes)
+{
+	const struct nvkm_vmm_desc *desc = it->desc;
+	const int type = desc->type == SPT;
+	struct nvkm_vmm_pt *pgt = it->pt[0];
+
+	/* Drop PTE references. */
+	pgt->refs[type] -= ptes;
+
+	/* Dual-PTs need special handling, unless PDE becoming invalid. */
+	if (desc->type == SPT && (pgt->refs[0] || pgt->refs[1]))
+		nvkm_vmm_unref_sptes(it, pgt, desc, ptei, ptes);
+
+	/* PT no longer neeed?  Destroy it. */
+	if (!pgt->refs[type]) {
+		it->lvl++;
+		TRA(it, "%s empty", nvkm_vmm_desc_type(desc));
+		it->lvl--;
+		nvkm_vmm_unref_pdes(it);
+		return false; /* PTE writes for unmap() not necessary. */
+	}
+
+	return true;
+}
+
+static void
+nvkm_vmm_ref_sptes(struct nvkm_vmm_iter *it, struct nvkm_vmm_pt *pgt,
+		   const struct nvkm_vmm_desc *desc, u32 ptei, u32 ptes)
+{
+	const struct nvkm_vmm_desc *pair = it->page[-1].desc;
+	const u32 sptb = desc->bits - pair->bits;
+	const u32 sptn = 1 << sptb;
+	struct nvkm_vmm *vmm = it->vmm;
+	u32 spti = ptei & (sptn - 1), lpti, pteb;
+
+	/* Determine how many SPTEs are being touched under each LPTE,
+	 * and increase reference counts.
+	 */
+	for (lpti = ptei >> sptb; ptes; spti = 0, lpti++) {
+		const u32 pten = min(sptn - spti, ptes);
+		pgt->pte[lpti] += pten;
+		ptes -= pten;
+	}
+
+	/* We're done here if there's no corresponding LPT. */
+	if (!pgt->refs[0])
+		return;
+
+	for (ptei = pteb = ptei >> sptb; ptei < lpti; pteb = ptei) {
+		/* Skip over any LPTEs that already have valid SPTEs. */
+		if (pgt->pte[pteb] & NVKM_VMM_PTE_VALID) {
+			for (ptes = 1, ptei++; ptei < lpti; ptes++, ptei++) {
+				if (!(pgt->pte[ptei] & NVKM_VMM_PTE_VALID))
+					break;
+			}
+			continue;
+		}
+
+		/* As there are now non-UNMAPPED SPTEs in the range covered
+		 * by a number of LPTEs, we need to transfer control of the
+		 * address range to the SPTEs.
+		 *
+		 * Determine how many LPTEs need to transition state.
+		 */
+		pgt->pte[ptei] |= NVKM_VMM_PTE_VALID;
+		for (ptes = 1, ptei++; ptei < lpti; ptes++, ptei++) {
+			if (pgt->pte[ptei] & NVKM_VMM_PTE_VALID)
+				break;
+			pgt->pte[ptei] |= NVKM_VMM_PTE_VALID;
+		}
+
+		if (pgt->pte[pteb] & NVKM_VMM_PTE_SPARSE) {
+			const u32 spti = pteb * sptn;
+			const u32 sptc = ptes * sptn;
+			/* The entire LPTE is marked as sparse, we need
+			 * to make sure that the SPTEs are too.
+			 */
+			TRA(it, "SPTE %05x: U -> S %d PTEs", spti, sptc);
+			desc->func->sparse(vmm, pgt->pt[1], spti, sptc);
+			/* Sparse LPTEs prevent SPTEs from being accessed. */
+			TRA(it, "LPTE %05x: S -> U %d PTEs", pteb, ptes);
+			pair->func->unmap(vmm, pgt->pt[0], pteb, ptes);
+		} else
+		if (pair->func->invalid) {
+			/* MMU supports blocking SPTEs by marking an LPTE
+			 * as INVALID.  We need to reverse that here.
+			 */
+			TRA(it, "LPTE %05x: I -> U %d PTEs", pteb, ptes);
+			pair->func->unmap(vmm, pgt->pt[0], pteb, ptes);
+		}
+	}
+}
+
+static bool
+nvkm_vmm_ref_ptes(struct nvkm_vmm_iter *it, u32 ptei, u32 ptes)
+{
+	const struct nvkm_vmm_desc *desc = it->desc;
+	const int type = desc->type == SPT;
+	struct nvkm_vmm_pt *pgt = it->pt[0];
+
+	/* Take PTE references. */
+	pgt->refs[type] += ptes;
+
+	/* Dual-PTs need special handling. */
+	if (desc->type == SPT)
+		nvkm_vmm_ref_sptes(it, pgt, desc, ptei, ptes);
+
+	return true;
+}
+
+static void
+nvkm_vmm_sparse_ptes(const struct nvkm_vmm_desc *desc,
+		     struct nvkm_vmm_pt *pgt, u32 ptei, u32 ptes)
+{
+	if (desc->type == PGD) {
+		while (ptes--)
+			pgt->pde[ptei++] = NVKM_VMM_PDE_SPARSE;
+	} else
+	if (desc->type == LPT) {
+		memset(&pgt->pte[ptei], NVKM_VMM_PTE_SPARSE, ptes);
+	}
+}
+
+static bool
+nvkm_vmm_ref_hwpt(struct nvkm_vmm_iter *it, struct nvkm_vmm_pt *pgd, u32 pdei)
+{
+	const struct nvkm_vmm_desc *desc = &it->desc[it->lvl - 1];
+	const int type = desc->type == SPT;
+	struct nvkm_vmm_pt *pgt = pgd->pde[pdei];
+	const bool zero = !pgt->sparse && !desc->func->invalid;
+	struct nvkm_vmm *vmm = it->vmm;
+	struct nvkm_mmu *mmu = vmm->mmu;
+	struct nvkm_mmu_pt *pt;
+	u32 pten = 1 << desc->bits;
+	u32 pteb, ptei, ptes;
+	u32 size = desc->size * pten;
+
+	pgd->refs[0]++;
+
+	pgt->pt[type] = nvkm_mmu_ptc_get(mmu, size, desc->align, zero);
+	if (!pgt->pt[type]) {
+		it->lvl--;
+		nvkm_vmm_unref_pdes(it);
+		return false;
+	}
+
+	if (zero)
+		goto done;
+
+	pt = pgt->pt[type];
+
+	if (desc->type == LPT && pgt->refs[1]) {
+		/* SPT already exists covering the same range as this LPT,
+		 * which means we need to be careful that any LPTEs which
+		 * overlap valid SPTEs are unmapped as opposed to invalid
+		 * or sparse, which would prevent the MMU from looking at
+		 * the SPTEs on some GPUs.
+		 */
+		for (ptei = pteb = 0; ptei < pten; pteb = ptei) {
+			bool spte = pgt->pte[ptei] & NVKM_VMM_PTE_SPTES;
+			for (ptes = 1, ptei++; ptei < pten; ptes++, ptei++) {
+				bool next = pgt->pte[ptei] & NVKM_VMM_PTE_SPTES;
+				if (spte != next)
+					break;
+			}
+
+			if (!spte) {
+				if (pgt->sparse)
+					desc->func->sparse(vmm, pt, pteb, ptes);
+				else
+					desc->func->invalid(vmm, pt, pteb, ptes);
+				memset(&pgt->pte[pteb], 0x00, ptes);
+			} else {
+				desc->func->unmap(vmm, pt, pteb, ptes);
+				while (ptes--)
+					pgt->pte[pteb++] |= NVKM_VMM_PTE_VALID;
+			}
+		}
+	} else {
+		if (pgt->sparse) {
+			nvkm_vmm_sparse_ptes(desc, pgt, 0, pten);
+			desc->func->sparse(vmm, pt, 0, pten);
+		} else {
+			desc->func->invalid(vmm, pt, 0, pten);
+		}
+	}
+
+done:
+	TRA(it, "PDE write %s", nvkm_vmm_desc_type(desc));
+	it->desc[it->lvl].func->pde(it->vmm, pgd, pdei);
+	nvkm_vmm_flush_mark(it);
+	return true;
+}
+
+static bool
+nvkm_vmm_ref_swpt(struct nvkm_vmm_iter *it, struct nvkm_vmm_pt *pgd, u32 pdei)
+{
+	const struct nvkm_vmm_desc *desc = &it->desc[it->lvl - 1];
+	struct nvkm_vmm_pt *pgt = pgd->pde[pdei];
+
+	pgt = nvkm_vmm_pt_new(desc, NVKM_VMM_PDE_SPARSED(pgt), it->page);
+	if (!pgt) {
+		if (!pgd->refs[0])
+			nvkm_vmm_unref_pdes(it);
+		return false;
+	}
+
+	pgd->pde[pdei] = pgt;
+	return true;
+}
+
+static inline u64
+nvkm_vmm_iter(struct nvkm_vmm *vmm, const struct nvkm_vmm_page *page,
+	      u64 addr, u64 size, const char *name, bool ref,
+	      bool (*REF_PTES)(struct nvkm_vmm_iter *, u32, u32),
+	      nvkm_vmm_pte_func MAP_PTES, struct nvkm_vmm_map *map,
+	      nvkm_vmm_pxe_func CLR_PTES)
+{
+	const struct nvkm_vmm_desc *desc = page->desc;
+	struct nvkm_vmm_iter it;
+	u64 bits = addr >> page->shift;
+
+	it.page = page;
+	it.desc = desc;
+	it.vmm = vmm;
+	it.cnt = size >> page->shift;
+	it.flush = NVKM_VMM_LEVELS_MAX;
+
+	/* Deconstruct address into PTE indices for each mapping level. */
+	for (it.lvl = 0; desc[it.lvl].bits; it.lvl++) {
+		it.pte[it.lvl] = bits & ((1 << desc[it.lvl].bits) - 1);
+		bits >>= desc[it.lvl].bits;
+	}
+	it.max = --it.lvl;
+	it.pt[it.max] = vmm->pd;
+
+	it.lvl = 0;
+	TRA(&it, "%s: %016llx %016llx %d %lld PTEs", name,
+	         addr, size, page->shift, it.cnt);
+	it.lvl = it.max;
+
+	/* Depth-first traversal of page tables. */
+	while (it.cnt) {
+		struct nvkm_vmm_pt *pgt = it.pt[it.lvl];
+		const int type = desc->type == SPT;
+		const u32 pten = 1 << desc->bits;
+		const u32 ptei = it.pte[0];
+		const u32 ptes = min_t(u64, it.cnt, pten - ptei);
+
+		/* Walk down the tree, finding page tables for each level. */
+		for (; it.lvl; it.lvl--) {
+			const u32 pdei = it.pte[it.lvl];
+			struct nvkm_vmm_pt *pgd = pgt;
+
+			/* Software PT. */
+			if (ref && NVKM_VMM_PDE_INVALID(pgd->pde[pdei])) {
+				if (!nvkm_vmm_ref_swpt(&it, pgd, pdei))
+					goto fail;
+			}
+			it.pt[it.lvl - 1] = pgt = pgd->pde[pdei];
+
+			/* Hardware PT.
+			 *
+			 * This is a separate step from above due to GF100 and
+			 * newer having dual page tables at some levels, which
+			 * are refcounted independently.
+			 */
+			if (ref && !pgt->refs[desc[it.lvl - 1].type == SPT]) {
+				if (!nvkm_vmm_ref_hwpt(&it, pgd, pdei))
+					goto fail;
+			}
+		}
+
+		/* Handle PTE updates. */
+		if (!REF_PTES || REF_PTES(&it, ptei, ptes)) {
+			struct nvkm_mmu_pt *pt = pgt->pt[type];
+			if (MAP_PTES || CLR_PTES) {
+				if (MAP_PTES)
+					MAP_PTES(vmm, pt, ptei, ptes, map);
+				else
+					CLR_PTES(vmm, pt, ptei, ptes);
+				nvkm_vmm_flush_mark(&it);
+			}
+		}
+
+		/* Walk back up the tree to the next position. */
+		it.pte[it.lvl] += ptes;
+		it.cnt -= ptes;
+		if (it.cnt) {
+			while (it.pte[it.lvl] == (1 << desc[it.lvl].bits)) {
+				it.pte[it.lvl++] = 0;
+				it.pte[it.lvl]++;
+			}
+		}
+	};
+
+	nvkm_vmm_flush(&it);
+	return ~0ULL;
+
+fail:
+	/* Reconstruct the failure address so the caller is able to
+	 * reverse any partially completed operations.
+	 */
+	addr = it.pte[it.max--];
+	do {
+		addr  = addr << desc[it.max].bits;
+		addr |= it.pte[it.max];
+	} while (it.max--);
+
+	return addr << page->shift;
+}
+
+void
+nvkm_vmm_ptes_unmap(struct nvkm_vmm *vmm, const struct nvkm_vmm_page *page,
+		    u64 addr, u64 size, bool sparse)
+{
+	const struct nvkm_vmm_desc_func *func = page->desc->func;
+	nvkm_vmm_iter(vmm, page, addr, size, "unmap", false, NULL, NULL, NULL,
+		      sparse ? func->sparse : func->invalid ? func->invalid :
+							      func->unmap);
+}
+
+void
+nvkm_vmm_ptes_map(struct nvkm_vmm *vmm, const struct nvkm_vmm_page *page,
+		  u64 addr, u64 size, struct nvkm_vmm_map *map,
+		  nvkm_vmm_pte_func func)
+{
+	nvkm_vmm_iter(vmm, page, addr, size, "map", false,
+		      NULL, func, map, NULL);
+}
+
+void
+nvkm_vmm_ptes_put(struct nvkm_vmm *vmm, const struct nvkm_vmm_page *page,
+		  u64 addr, u64 size)
+{
+	nvkm_vmm_iter(vmm, page, addr, size, "unref", false,
+		      nvkm_vmm_unref_ptes, NULL, NULL, NULL);
+}
+
+int
+nvkm_vmm_ptes_get(struct nvkm_vmm *vmm, const struct nvkm_vmm_page *page,
+		  u64 addr, u64 size)
+{
+	u64 fail = nvkm_vmm_iter(vmm, page, addr, size, "ref", true,
+				 nvkm_vmm_ref_ptes, NULL, NULL, NULL);
+	if (fail != ~0ULL) {
+		if (fail != addr)
+			nvkm_vmm_ptes_put(vmm, page, addr, fail - addr);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
 void
 nvkm_vmm_dtor(struct nvkm_vmm *vmm)
 {
+	if (vmm->bootstrapped) {
+		const struct nvkm_vmm_page *page = vmm->func->page;
+		const u64 limit = vmm->limit - vmm->start;
+
+		while (page[1].shift)
+			page++;
+
+		nvkm_mmu_ptc_dump(vmm->mmu);
+		nvkm_vmm_ptes_put(vmm, page, vmm->start, limit);
+	}
+
 	if (vmm->nullp) {
 		dma_free_coherent(vmm->mmu->subdev.device->dev, 16 * 1024,
 				  vmm->nullp, vmm->null);
@@ -94,6 +644,7 @@ nvkm_vmm_ctor(const struct nvkm_vmm_func *func, struct nvkm_mmu *mmu,
 	vmm->func = func;
 	vmm->mmu = mmu;
 	vmm->name = name;
+	vmm->debug = mmu->subdev.debug;
 	kref_init(&vmm->kref);
 
 	__mutex_init(&vmm->mutex, "&vmm->mutex", key ? key : &_key);
@@ -150,3 +701,32 @@ nvkm_vmm_new_(const struct nvkm_vmm_func *func, struct nvkm_mmu *mmu,
 		return -ENOMEM;
 	return nvkm_vmm_ctor(func, mmu, hdr, addr, size, key, name, *pvmm);
 }
+
+static bool
+nvkm_vmm_boot_ptes(struct nvkm_vmm_iter *it, u32 ptei, u32 ptes)
+{
+	const struct nvkm_vmm_desc *desc = it->desc;
+	const int type = desc->type == SPT;
+	nvkm_memory_boot(it->pt[0]->pt[type]->memory, it->vmm);
+	return false;
+}
+
+int
+nvkm_vmm_boot(struct nvkm_vmm *vmm)
+{
+	const struct nvkm_vmm_page *page = vmm->func->page;
+	const u64 limit = vmm->limit - vmm->start;
+	int ret;
+
+	while (page[1].shift)
+		page++;
+
+	ret = nvkm_vmm_ptes_get(vmm, page, vmm->start, limit);
+	if (ret)
+		return ret;
+
+	nvkm_vmm_iter(vmm, page, vmm->start, limit, "bootstrap", false,
+		      nvkm_vmm_boot_ptes, NULL, NULL, NULL);
+	vmm->bootstrapped = true;
+	return 0;
+}