drm/amdgpu: Override MTYPE per page on GFXv9.4.3 APUs

On GFXv9.4.3 NUMA APUs, system memory locality must be determined per
page to choose the correct MTYPE. This patch adds a GMC callback that
can provide this per-page override and implements it for native mode.

Carve-out mode is not yet supported and will use the safe default
(remote) MTYPE for system memory.
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Philip Yang <Philip.Yang@amd.com>
Reviewed-and-tested-by: Rajneesh Bhardwaj <rajneesh.bhardwaj@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_gmc.h

@@ -148,6 +148,10 @@ struct amdgpu_gmc_funcs {
 	void (*get_vm_pte)(struct amdgpu_device *adev,
 			   struct amdgpu_bo_va_mapping *mapping,
 			   uint64_t *flags);
+	/* override per-page pte flags */
+	void (*override_vm_pte_flags)(struct amdgpu_device *dev,
+				      struct amdgpu_vm *vm,
+				      uint64_t addr, uint64_t *flags);
 	/* get the amount of memory used by the vbios for pre-OS console */
 	unsigned int (*get_vbios_fb_size)(struct amdgpu_device *adev);
 
@@ -336,6 +340,9 @@ struct amdgpu_gmc {
 #define amdgpu_gmc_map_mtype(adev, flags) (adev)->gmc.gmc_funcs->map_mtype((adev),(flags))
 #define amdgpu_gmc_get_vm_pde(adev, level, dst, flags) (adev)->gmc.gmc_funcs->get_vm_pde((adev), (level), (dst), (flags))
 #define amdgpu_gmc_get_vm_pte(adev, mapping, flags) (adev)->gmc.gmc_funcs->get_vm_pte((adev), (mapping), (flags))
+#define amdgpu_gmc_override_vm_pte_flags(adev, vm, addr, pte_flags)	\
+	(adev)->gmc.gmc_funcs->override_vm_pte_flags			\
+		((adev), (vm), (addr), (pte_flags))
 #define amdgpu_gmc_get_vbios_fb_size(adev) (adev)->gmc.gmc_funcs->get_vbios_fb_size((adev))
 
 /**

drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c

@@ -786,13 +786,14 @@ static void amdgpu_vm_pte_update_flags(struct amdgpu_vm_update_params *params,
 				       uint64_t pe, uint64_t addr,
 				       unsigned int count, uint32_t incr,
 				       uint64_t flags)
-
 {
+	struct amdgpu_device *adev = params->adev;
+
 	if (level != AMDGPU_VM_PTB) {
 		flags |= AMDGPU_PDE_PTE;
-		amdgpu_gmc_get_vm_pde(params->adev, level, &addr, &flags);
+		amdgpu_gmc_get_vm_pde(adev, level, &addr, &flags);
 
-	} else if (params->adev->asic_type >= CHIP_VEGA10 &&
+	} else if (adev->asic_type >= CHIP_VEGA10 &&
 		   !(flags & AMDGPU_PTE_VALID) &&
 		   !(flags & AMDGPU_PTE_PRT)) {
 
@@ -800,6 +801,21 @@ static void amdgpu_vm_pte_update_flags(struct amdgpu_vm_update_params *params,
 		flags |= AMDGPU_PTE_EXECUTABLE;
 	}
 
+	/* APUs mapping system memory may need different MTYPEs on different
+	 * NUMA nodes. Only do this for contiguous ranges that can be assumed
+	 * to be on the same NUMA node.
+	 */
+	if ((flags & AMDGPU_PTE_SYSTEM) && (adev->flags & AMD_IS_APU) &&
+	    adev->gmc.gmc_funcs->override_vm_pte_flags &&
+	    num_possible_nodes() > 1) {
+		if (!params->pages_addr)
+			amdgpu_gmc_override_vm_pte_flags(adev, params->vm,
+							 addr, &flags);
+		else
+			dev_dbg(adev->dev,
+				"override_vm_pte_flags skipped: non-contiguous\n");
+	}
+
 	params->vm->update_funcs->update(params, pt, pe, addr, count, incr,
 					 flags);
 }

drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c

@@ -1297,6 +1297,69 @@ static void gmc_v9_0_get_vm_pte(struct amdgpu_device *adev,
 					     mapping, flags);
 }
 
+static void gmc_v9_0_override_vm_pte_flags(struct amdgpu_device *adev,
+					   struct amdgpu_vm *vm,
+					   uint64_t addr, uint64_t *flags)
+{
+	int local_node, nid;
+
+	/* Only GFX 9.4.3 APUs associate GPUs with NUMA nodes. Local system
+	 * memory can use more efficient MTYPEs.
+	 */
+	if (adev->ip_versions[GC_HWIP][0] != IP_VERSION(9, 4, 3))
+		return;
+
+	/* Only direct-mapped memory allows us to determine the NUMA node from
+	 * the DMA address.
+	 */
+	if (!adev->ram_is_direct_mapped) {
+		dev_dbg(adev->dev, "RAM is not direct mapped\n");
+		return;
+	}
+
+	/* Only override mappings with MTYPE_NC, which is the safe default for
+	 * cacheable memory.
+	 */
+	if ((*flags & AMDGPU_PTE_MTYPE_VG10_MASK) !=
+	    AMDGPU_PTE_MTYPE_VG10(MTYPE_NC)) {
+		dev_dbg(adev->dev, "MTYPE is not NC\n");
+		return;
+	}
+
+	/* TODO: memory partitions. mem_id is hard-coded to 0 for now.
+	 * FIXME: Only supported on native mode for now. For carve-out, the
+	 * NUMA affinity of the GPU/VM needs to come from the PCI info because
+	 * memory partitions are not associated with different NUMA nodes.
+	 */
+	if (adev->gmc.is_app_apu) {
+		local_node = adev->gmc.mem_partitions[/*vm->mem_id*/0].numa.node;
+	} else {
+		dev_dbg(adev->dev, "Only native mode APU is supported.\n");
+		return;
+	}
+
+	/* Only handle real RAM. Mappings of PCIe resources don't have struct
+	 * page or NUMA nodes.
+	 */
+	if (!page_is_ram(addr >> PAGE_SHIFT)) {
+		dev_dbg(adev->dev, "Page is not RAM.\n");
+		return;
+	}
+	nid = pfn_to_nid(addr >> PAGE_SHIFT);
+	dev_dbg(adev->dev, "vm->mem_id=%d, local_node=%d, nid=%d\n",
+		/*vm->mem_id*/0, local_node, nid);
+	if (nid == local_node) {
+		unsigned int mtype_local =
+			amdgpu_use_mtype_cc_wa ? MTYPE_CC : MTYPE_RW;
+		uint64_t old_flags = *flags;
+
+		*flags = (*flags & ~AMDGPU_PTE_MTYPE_VG10_MASK) |
+			 AMDGPU_PTE_MTYPE_VG10(mtype_local);
+		dev_dbg(adev->dev, "flags updated from %llx to %llx\n",
+			old_flags, *flags);
+	}
+}
+
 static unsigned gmc_v9_0_get_vbios_fb_size(struct amdgpu_device *adev)
 {
 	u32 d1vga_control = RREG32_SOC15(DCE, 0, mmD1VGA_CONTROL);
@@ -1368,6 +1431,7 @@ static const struct amdgpu_gmc_funcs gmc_v9_0_gmc_funcs = {
 	.map_mtype = gmc_v9_0_map_mtype,
 	.get_vm_pde = gmc_v9_0_get_vm_pde,
 	.get_vm_pte = gmc_v9_0_get_vm_pte,
+	.override_vm_pte_flags = gmc_v9_0_override_vm_pte_flags,
 	.get_vbios_fb_size = gmc_v9_0_get_vbios_fb_size,
 	.query_mem_partition_mode = &gmc_v9_0_query_memory_partition,
 };