diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst
index a3b6850895128b02a3343d336b08dd84a187f9a8..eba50afbda424a1f240c9b9bff33ecdb4688c7c3 100644
--- a/Documentation/gpu/drm-mm.rst
+++ b/Documentation/gpu/drm-mm.rst
@@ -79,7 +79,6 @@ count for the TTM, which will call your initialization function.
See the radeon_ttm.c file for an example of usage.
-
The Graphics Execution Manager (GEM)
====================================
@@ -395,6 +394,18 @@ GEM VRAM Helper Functions Reference
.. kernel-doc:: drivers/gpu/drm/drm_gem_vram_helper.c
:export:
+VRAM MM Helper Functions Reference
+----------------------------------
+
+.. kernel-doc:: drivers/gpu/drm/drm_vram_mm_helper.c
+ :doc: overview
+
+.. kernel-doc:: include/drm/drm_vram_mm_helper.h
+ :internal:
+
+.. kernel-doc:: drivers/gpu/drm/drm_vram_mm_helper.c
+ :export:
+
VMA Offset Manager
==================
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index ed49b24807664e08ab7d79cde0e728160785aad1..4c3dc4268b652c0a1b07e4c0455ad798585987b6 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -33,7 +33,8 @@ drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o
drm-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
drm_vram_helper-y := drm_gem_vram_helper.o \
- drm_vram_helper_common.o
+ drm_vram_helper_common.o \
+ drm_vram_mm_helper.o
obj-$(CONFIG_DRM_VRAM_HELPER) += drm_vram_helper.o
drm_kms_helper-y := drm_crtc_helper.o drm_dp_helper.o drm_dsc.o drm_probe_helper.o \
diff --git a/drivers/gpu/drm/drm_vram_mm_helper.c b/drivers/gpu/drm/drm_vram_mm_helper.c
new file mode 100644
index 0000000000000000000000000000000000000000..d17c5169b018ae9a14aed68b01cfedab39e89d94
--- /dev/null
+++ b/drivers/gpu/drm/drm_vram_mm_helper.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <drm/drm_vram_mm_helper.h>
+#include <drm/drmP.h>
+#include <drm/ttm/ttm_page_alloc.h>
+
+/**
+ * DOC: overview
+ *
+ * The data structure &struct drm_vram_mm and its helpers implement a memory
+ * manager for simple framebuffer devices with dedicated video memory. Buffer
+ * objects are either placed in video RAM or evicted to system memory. These
+ * helper functions work well with &struct drm_gem_vram_object.
+ */
+
+/*
+ * TTM TT
+ */
+
+static void backend_func_destroy(struct ttm_tt *tt)
+{
+ ttm_tt_fini(tt);
+ kfree(tt);
+}
+
+static struct ttm_backend_func backend_func = {
+ .destroy = backend_func_destroy
+};
+
+/*
+ * TTM BO device
+ */
+
+static struct ttm_tt *bo_driver_ttm_tt_create(struct ttm_buffer_object *bo,
+ uint32_t page_flags)
+{
+ struct ttm_tt *tt;
+ int ret;
+
+ tt = kzalloc(sizeof(*tt), GFP_KERNEL);
+ if (!tt)
+ return NULL;
+
+ tt->func = &backend_func;
+
+ ret = ttm_tt_init(tt, bo, page_flags);
+ if (ret < 0)
+ goto err_ttm_tt_init;
+
+ return tt;
+
+err_ttm_tt_init:
+ kfree(tt);
+ return NULL;
+}
+
+static int bo_driver_init_mem_type(struct ttm_bo_device *bdev, uint32_t type,
+ struct ttm_mem_type_manager *man)
+{
+ switch (type) {
+ case TTM_PL_SYSTEM:
+ man->flags = TTM_MEMTYPE_FLAG_MAPPABLE;
+ man->available_caching = TTM_PL_MASK_CACHING;
+ man->default_caching = TTM_PL_FLAG_CACHED;
+ break;
+ case TTM_PL_VRAM:
+ man->func = &ttm_bo_manager_func;
+ man->flags = TTM_MEMTYPE_FLAG_FIXED |
+ TTM_MEMTYPE_FLAG_MAPPABLE;
+ man->available_caching = TTM_PL_FLAG_UNCACHED |
+ TTM_PL_FLAG_WC;
+ man->default_caching = TTM_PL_FLAG_WC;
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static void bo_driver_evict_flags(struct ttm_buffer_object *bo,
+ struct ttm_placement *placement)
+{
+ struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bo->bdev);
+
+ if (vmm->funcs && vmm->funcs->evict_flags)
+ vmm->funcs->evict_flags(bo, placement);
+}
+
+static int bo_driver_verify_access(struct ttm_buffer_object *bo,
+ struct file *filp)
+{
+ struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bo->bdev);
+
+ if (!vmm->funcs || !vmm->funcs->verify_access)
+ return 0;
+ return vmm->funcs->verify_access(bo, filp);
+}
+
+static int bo_driver_io_mem_reserve(struct ttm_bo_device *bdev,
+ struct ttm_mem_reg *mem)
+{
+ struct ttm_mem_type_manager *man = bdev->man + mem->mem_type;
+ struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bdev);
+
+ if (!(man->flags & TTM_MEMTYPE_FLAG_MAPPABLE))
+ return -EINVAL;
+
+ mem->bus.addr = NULL;
+ mem->bus.size = mem->num_pages << PAGE_SHIFT;
+
+ switch (mem->mem_type) {
+ case TTM_PL_SYSTEM: /* nothing to do */
+ mem->bus.offset = 0;
+ mem->bus.base = 0;
+ mem->bus.is_iomem = false;
+ break;
+ case TTM_PL_VRAM:
+ mem->bus.offset = mem->start << PAGE_SHIFT;
+ mem->bus.base = vmm->vram_base;
+ mem->bus.is_iomem = true;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void bo_driver_io_mem_free(struct ttm_bo_device *bdev,
+ struct ttm_mem_reg *mem)
+{ }
+
+static struct ttm_bo_driver bo_driver = {
+ .ttm_tt_create = bo_driver_ttm_tt_create,
+ .ttm_tt_populate = ttm_pool_populate,
+ .ttm_tt_unpopulate = ttm_pool_unpopulate,
+ .init_mem_type = bo_driver_init_mem_type,
+ .eviction_valuable = ttm_bo_eviction_valuable,
+ .evict_flags = bo_driver_evict_flags,
+ .verify_access = bo_driver_verify_access,
+ .io_mem_reserve = bo_driver_io_mem_reserve,
+ .io_mem_free = bo_driver_io_mem_free,
+};
+
+/*
+ * struct drm_vram_mm
+ */
+
+/**
+ * drm_vram_mm_init() - Initialize an instance of VRAM MM.
+ * @vmm: the VRAM MM instance to initialize
+ * @dev: the DRM device
+ * @vram_base: the base address of the video memory
+ * @vram_size: the size of the video memory in bytes
+ * @funcs: callback functions for buffer objects
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise.
+ */
+int drm_vram_mm_init(struct drm_vram_mm *vmm, struct drm_device *dev,
+ uint64_t vram_base, size_t vram_size,
+ const struct drm_vram_mm_funcs *funcs)
+{
+ int ret;
+
+ vmm->vram_base = vram_base;
+ vmm->vram_size = vram_size;
+ vmm->funcs = funcs;
+
+ ret = ttm_bo_device_init(&vmm->bdev, &bo_driver,
+ dev->anon_inode->i_mapping,
+ true);
+ if (ret)
+ return ret;
+
+ ret = ttm_bo_init_mm(&vmm->bdev, TTM_PL_VRAM, vram_size >> PAGE_SHIFT);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_vram_mm_init);
+
+/**
+ * drm_vram_mm_cleanup() - Cleans up an initialized instance of VRAM MM.
+ * @vmm: the VRAM MM instance to clean up
+ */
+void drm_vram_mm_cleanup(struct drm_vram_mm *vmm)
+{
+ ttm_bo_device_release(&vmm->bdev);
+}
+EXPORT_SYMBOL(drm_vram_mm_cleanup);
+
+/**
+ * drm_vram_mm_mmap() - Helper for implementing &struct file_operations.mmap()
+ * @filp: the mapping's file structure
+ * @vma: the mapping's memory area
+ * @vmm: the VRAM MM instance
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise.
+ */
+int drm_vram_mm_mmap(struct file *filp, struct vm_area_struct *vma,
+ struct drm_vram_mm *vmm)
+{
+ return ttm_bo_mmap(filp, vma, &vmm->bdev);
+}
+EXPORT_SYMBOL(drm_vram_mm_mmap);
diff --git a/include/drm/drm_vram_mm_helper.h b/include/drm/drm_vram_mm_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..5d45c6447fa4ec13557bee68c34a7f491898fb87
--- /dev/null
+++ b/include/drm/drm_vram_mm_helper.h
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef DRM_VRAM_MM_HELPER_H
+#define DRM_VRAM_MM_HELPER_H
+
+#include <drm/ttm/ttm_bo_driver.h>
+
+struct drm_device;
+
+/**
+ * struct drm_vram_mm_funcs - Callback functions for &struct drm_vram_mm
+ * @evict_flags: Provides an implementation for struct \
+ &ttm_bo_driver.evict_flags
+ * @verify_access: Provides an implementation for \
+ struct &ttm_bo_driver.verify_access
+ *
+ * These callback function integrate VRAM MM with TTM buffer objects. New
+ * functions can be added if necessary.
+ */
+struct drm_vram_mm_funcs {
+ void (*evict_flags)(struct ttm_buffer_object *bo,
+ struct ttm_placement *placement);
+ int (*verify_access)(struct ttm_buffer_object *bo, struct file *filp);
+};
+
+/**
+ * struct drm_vram_mm - An instance of VRAM MM
+ * @vram_base: Base address of the managed video memory
+ * @vram_size: Size of the managed video memory in bytes
+ * @bdev: The TTM BO device.
+ * @funcs: TTM BO functions
+ *
+ * The fields &struct drm_vram_mm.vram_base and
+ * &struct drm_vram_mm.vrm_size are managed by VRAM MM, but are
+ * available for public read access. Use the field
+ * &struct drm_vram_mm.bdev to access the TTM BO device.
+ */
+struct drm_vram_mm {
+ uint64_t vram_base;
+ size_t vram_size;
+
+ struct ttm_bo_device bdev;
+
+ const struct drm_vram_mm_funcs *funcs;
+};
+
+/**
+ * drm_vram_mm_of_bdev() - \
+ Returns the container of type &struct ttm_bo_device for field bdev.
+ * @bdev: the TTM BO device
+ *
+ * Returns:
+ * The containing instance of &struct drm_vram_mm
+ */
+static inline struct drm_vram_mm *drm_vram_mm_of_bdev(
+ struct ttm_bo_device *bdev)
+{
+ return container_of(bdev, struct drm_vram_mm, bdev);
+}
+
+int drm_vram_mm_init(struct drm_vram_mm *vmm, struct drm_device *dev,
+ uint64_t vram_base, size_t vram_size,
+ const struct drm_vram_mm_funcs *funcs);
+void drm_vram_mm_cleanup(struct drm_vram_mm *vmm);
+
+int drm_vram_mm_mmap(struct file *filp, struct vm_area_struct *vma,
+ struct drm_vram_mm *vmm);
+
+#endif