[RFC PATCH v2 4/8] drm/amdkfd: add SPM support for SVM
From: Alex Sierra <hidden>
Date: 2021-06-07 20:43:04
Also in:
amd-gfx, dri-devel
Subsystem:
amd kfd, drm drivers, radeon and amdgpu drm drivers, the rest · Maintainers:
Felix Kuehling, David Airlie, Simona Vetter, Alex Deucher, Christian König, Linus Torvalds
When CPU is connected throug XGMI, it has coherent access to VRAM resource. In this case that resource is taken from a table in the device gmc aperture base. This resource is used along with the device type, which could be DEVICE_PRIVATE or DEVICE_GENERIC to create the device page map region. Signed-off-by: Alex Sierra <redacted> Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com> --- drivers/gpu/drm/amd/amdkfd/kfd_migrate.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
index c8ca3252cbc2..f5939449a99f 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_migrate.c@@ -895,6 +895,7 @@ int svm_migrate_init(struct amdgpu_device *adev) struct resource *res; unsigned long size; void *r; + bool xgmi_connected_to_cpu = adev->gmc.xgmi.connected_to_cpu; /* Page migration works on Vega10 or newer */ if (kfddev->device_info->asic_family < CHIP_VEGA10)
@@ -907,17 +908,22 @@ int svm_migrate_init(struct amdgpu_device *adev) * should remove reserved size */ size = ALIGN(adev->gmc.real_vram_size, 2ULL << 20); - res = devm_request_free_mem_region(adev->dev, &iomem_resource, size); + if (xgmi_connected_to_cpu) + res = lookup_resource(&iomem_resource, adev->gmc.aper_base); + else + res = devm_request_free_mem_region(adev->dev, &iomem_resource, size); + if (IS_ERR(res)) return -ENOMEM; - pgmap->type = MEMORY_DEVICE_PRIVATE; pgmap->nr_range = 1; pgmap->range.start = res->start; pgmap->range.end = res->end; + pgmap->type = xgmi_connected_to_cpu ? + MEMORY_DEVICE_GENERIC : MEMORY_DEVICE_PRIVATE; pgmap->ops = &svm_migrate_pgmap_ops; pgmap->owner = SVM_ADEV_PGMAP_OWNER(adev); - pgmap->flags = MIGRATE_VMA_SELECT_DEVICE_PRIVATE; + pgmap->flags = 0; r = devm_memremap_pages(adev->dev, pgmap); if (IS_ERR(r)) { pr_err("failed to register HMM device memory\n");
--
2.17.1