releases/6.19.6/drm-amdgpu-gpu-vm-support-5-level-page-table.patch

From 6df47a568f7285306db15f1d0726f96c522185ec Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Fri, 25 Apr 2025 10:55:07 -0400
Subject: drm/amdgpu: GPU vm support 5-level page table

From: Philip Yang <Philip.Yang@amd.com>

[ Upstream commit f6b1c1f5fd7237f77fc3880603ea54dcf0371a20 ]

If GPU supports 5-level page table, but CPU disable 5-level page table
by using boot option no5lvl or CPU feature not available, the virtual
address will be 48bit, not needed to enable 5-level page table on GPU
vm.

If adev->vm_manager.num_level, number of pde levels, set to 4, then
gfxhub and mmhub register VM_CONTEXTx_CNTL/PAGE_TABLE_DEPTH will set
to 4 to enable 5-level page table in page table walker.

Set vm_manager.root_level to AMDGPU_VM_PDE3, then update GPU mapping
will allocate and update PDE3/PDE2/PDE1/PDE0/PTB 5-level page tables.

If max_level is not 4, no change for the logic to support features
needed by old ASICs.

v2: squash in CONFIG fix

Signed-off-by: Philip Yang <Philip.Yang@amd.com>
Acked-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Stable-dep-of: 3b948dd0366a ("drm/amdgpu: Use 5-level paging if gmc support 57-bit VA")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c    | 20 ++++++++++++++++++++
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h    |  3 ++-
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c |  1 +
 3 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index a67285118c37b..4d329454456bc 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -2360,9 +2360,26 @@ void amdgpu_vm_adjust_size(struct amdgpu_device *adev, uint32_t min_vm_size,
 			   unsigned max_bits)
 {
 	unsigned int max_size = 1 << (max_bits - 30);
+	bool sys_5level_pgtable = false;
 	unsigned int vm_size;
 	uint64_t tmp;
 
+#ifdef CONFIG_X86_64
+	/*
+	 * Refer to function configure_5level_paging() for details.
+	 */
+	sys_5level_pgtable = (native_read_cr4() & X86_CR4_LA57);
+#endif
+
+	/*
+	 * If GPU supports 5-level page table, but system uses 4-level page table,
+	 * then use 4-level page table on GPU
+	 */
+	if (max_level == 4 && !sys_5level_pgtable) {
+		min_vm_size = 256 * 1024;
+		max_level = 3;
+	}
+
 	/* adjust vm size first */
 	if (amdgpu_vm_size != -1) {
 		vm_size = amdgpu_vm_size;
@@ -2405,6 +2422,9 @@ void amdgpu_vm_adjust_size(struct amdgpu_device *adev, uint32_t min_vm_size,
 	tmp = DIV_ROUND_UP(fls64(tmp) - 1, 9) - 1;
 	adev->vm_manager.num_level = min_t(unsigned int, max_level, tmp);
 	switch (adev->vm_manager.num_level) {
+	case 4:
+		adev->vm_manager.root_level = AMDGPU_VM_PDB3;
+		break;
 	case 3:
 		adev->vm_manager.root_level = AMDGPU_VM_PDB2;
 		break;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
index 15d757c016cbb..de53176a398dc 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h
@@ -185,9 +185,10 @@ struct amdgpu_bo_vm;
 #define AMDGPU_VM_USE_CPU_FOR_COMPUTE (1 << 1)
 
 /* VMPT level enumerate, and the hiberachy is:
- * PDB2->PDB1->PDB0->PTB
+ * PDB3->PDB2->PDB1->PDB0->PTB
  */
 enum amdgpu_vm_level {
+	AMDGPU_VM_PDB3,
 	AMDGPU_VM_PDB2,
 	AMDGPU_VM_PDB1,
 	AMDGPU_VM_PDB0,
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
index f794fb1cc06e6..c7a7d51080a87 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c
@@ -51,6 +51,7 @@ static unsigned int amdgpu_vm_pt_level_shift(struct amdgpu_device *adev,
 					     unsigned int level)
 {
 	switch (level) {
+	case AMDGPU_VM_PDB3:
 	case AMDGPU_VM_PDB2:
 	case AMDGPU_VM_PDB1:
 	case AMDGPU_VM_PDB0:
-- 
2.51.0