diff --git a/Documentation/gpu/drm-mm.rst b/Documentation/gpu/drm-mm.rst
index 54a696d961a7c923761c0765f985039d575e32e7..a3b6850895128b02a3343d336b08dd84a187f9a8 100644
--- a/Documentation/gpu/drm-mm.rst
+++ b/Documentation/gpu/drm-mm.rst
@@ -380,6 +380,21 @@ GEM CMA Helper Functions Reference
.. kernel-doc:: drivers/gpu/drm/drm_gem_cma_helper.c
:export:
+VRAM Helper Function Reference
+==============================
+
+GEM VRAM Helper Functions Reference
+-----------------------------------
+
+.. kernel-doc:: drivers/gpu/drm/drm_gem_vram_helper.c
+ :doc: overview
+
+.. kernel-doc:: include/drm/drm_gem_vram_helper.h
+ :internal:
+
+.. kernel-doc:: drivers/gpu/drm/drm_gem_vram_helper.c
+ :export:
+
VMA Offset Manager
==================
diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 2267e84d5cb43be062384afd76dc1b6c77adca75..13d7b321db0d619983aa5ad4b34fdfa6fdb2e4b0 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -160,6 +160,13 @@ config DRM_TTM
GPU memory types. Will be enabled automatically if a device driver
uses it.
+config DRM_VRAM_HELPER
+ tristate
+ depends on DRM
+ select DRM_TTM
+ help
+ Helpers for VRAM memory management
+
config DRM_GEM_CMA_HELPER
bool
depends on DRM
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 72f5036d9bfabe0291bf3062f2272dea6a130606..ed49b24807664e08ab7d79cde0e728160785aad1 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -32,6 +32,10 @@ drm-$(CONFIG_AGP) += drm_agpsupport.o
drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o
drm-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o
+drm_vram_helper-y := drm_gem_vram_helper.o \
+ drm_vram_helper_common.o
+obj-$(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 \
drm_plane_helper.o drm_dp_mst_topology.o drm_atomic_helper.o \
drm_kms_helper_common.o drm_dp_dual_mode_helper.o \
diff --git a/drivers/gpu/drm/drm_gem_vram_helper.c b/drivers/gpu/drm/drm_gem_vram_helper.c
new file mode 100644
index 0000000000000000000000000000000000000000..761a546412f85872787f504cf95c0a1f0c5bebed
--- /dev/null
+++ b/drivers/gpu/drm/drm_gem_vram_helper.c
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <drm/drm_gem_vram_helper.h>
+#include <drm/ttm/ttm_page_alloc.h>
+
+/**
+ * DOC: overview
+ *
+ * This library provides a GEM buffer object that is backed by video RAM
+ * (VRAM). It can be used for framebuffer devices with dedicated memory.
+ */
+
+/*
+ * Buffer-objects helpers
+ */
+
+static void drm_gem_vram_cleanup(struct drm_gem_vram_object *gbo)
+{
+ /* We got here via ttm_bo_put(), which means that the
+ * TTM buffer object in 'bo' has already been cleaned
+ * up; only release the GEM object.
+ */
+ drm_gem_object_release(&gbo->gem);
+}
+
+static void drm_gem_vram_destroy(struct drm_gem_vram_object *gbo)
+{
+ drm_gem_vram_cleanup(gbo);
+ kfree(gbo);
+}
+
+static void ttm_buffer_object_destroy(struct ttm_buffer_object *bo)
+{
+ struct drm_gem_vram_object *gbo = drm_gem_vram_of_bo(bo);
+
+ drm_gem_vram_destroy(gbo);
+}
+
+static void drm_gem_vram_placement(struct drm_gem_vram_object *gbo,
+ unsigned long pl_flag)
+{
+ unsigned int i;
+ unsigned int c = 0;
+
+ gbo->placement.placement = gbo->placements;
+ gbo->placement.busy_placement = gbo->placements;
+
+ if (pl_flag & TTM_PL_FLAG_VRAM)
+ gbo->placements[c++].flags = TTM_PL_FLAG_WC |
+ TTM_PL_FLAG_UNCACHED |
+ TTM_PL_FLAG_VRAM;
+
+ if (pl_flag & TTM_PL_FLAG_SYSTEM)
+ gbo->placements[c++].flags = TTM_PL_MASK_CACHING |
+ TTM_PL_FLAG_SYSTEM;
+
+ if (!c)
+ gbo->placements[c++].flags = TTM_PL_MASK_CACHING |
+ TTM_PL_FLAG_SYSTEM;
+
+ gbo->placement.num_placement = c;
+ gbo->placement.num_busy_placement = c;
+
+ for (i = 0; i < c; ++i) {
+ gbo->placements[i].fpfn = 0;
+ gbo->placements[i].lpfn = 0;
+ }
+}
+
+static int drm_gem_vram_init(struct drm_device *dev,
+ struct ttm_bo_device *bdev,
+ struct drm_gem_vram_object *gbo,
+ size_t size, unsigned long pg_align,
+ bool interruptible)
+{
+ int ret;
+ size_t acc_size;
+
+ ret = drm_gem_object_init(dev, &gbo->gem, size);
+ if (ret)
+ return ret;
+
+ acc_size = ttm_bo_dma_acc_size(bdev, size, sizeof(*gbo));
+
+ gbo->bo.bdev = bdev;
+ drm_gem_vram_placement(gbo, TTM_PL_FLAG_VRAM | TTM_PL_FLAG_SYSTEM);
+
+ ret = ttm_bo_init(bdev, &gbo->bo, size, ttm_bo_type_device,
+ &gbo->placement, pg_align, interruptible, acc_size,
+ NULL, NULL, ttm_buffer_object_destroy);
+ if (ret)
+ goto err_drm_gem_object_release;
+
+ return 0;
+
+err_drm_gem_object_release:
+ drm_gem_object_release(&gbo->gem);
+ return ret;
+}
+
+/**
+ * drm_gem_vram_create() - Creates a VRAM-backed GEM object
+ * @dev: the DRM device
+ * @bdev: the TTM BO device backing the object
+ * @size: the buffer size in bytes
+ * @pg_align: the buffer's alignment in multiples of the page size
+ * @interruptible: sleep interruptible if waiting for memory
+ *
+ * Returns:
+ * A new instance of &struct drm_gem_vram_object on success, or
+ * an ERR_PTR()-encoded error code otherwise.
+ */
+struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
+ struct ttm_bo_device *bdev,
+ size_t size,
+ unsigned long pg_align,
+ bool interruptible)
+{
+ struct drm_gem_vram_object *gbo;
+ int ret;
+
+ gbo = kzalloc(sizeof(*gbo), GFP_KERNEL);
+ if (!gbo)
+ return ERR_PTR(-ENOMEM);
+
+ ret = drm_gem_vram_init(dev, bdev, gbo, size, pg_align, interruptible);
+ if (ret < 0)
+ goto err_kfree;
+
+ return gbo;
+
+err_kfree:
+ kfree(gbo);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(drm_gem_vram_create);
+
+/**
+ * drm_gem_vram_put() - Releases a reference to a VRAM-backed GEM object
+ * @gbo: the GEM VRAM object
+ *
+ * See ttm_bo_put() for more information.
+ */
+void drm_gem_vram_put(struct drm_gem_vram_object *gbo)
+{
+ ttm_bo_put(&gbo->bo);
+}
+EXPORT_SYMBOL(drm_gem_vram_put);
+
+/**
+ * drm_gem_vram_reserve() - Reserves a VRAM-backed GEM object
+ * @gbo: the GEM VRAM object
+ * @no_wait: don't wait for buffer object to become available
+ *
+ * See ttm_bo_reserve() for more information.
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise
+ */
+int drm_gem_vram_reserve(struct drm_gem_vram_object *gbo, bool no_wait)
+{
+ return ttm_bo_reserve(&gbo->bo, true, no_wait, NULL);
+}
+EXPORT_SYMBOL(drm_gem_vram_reserve);
+
+/**
+ * drm_gem_vram_unreserve() - \
+ Release a reservation acquired by drm_gem_vram_reserve()
+ * @gbo: the GEM VRAM object
+ *
+ * See ttm_bo_unreserve() for more information.
+ */
+void drm_gem_vram_unreserve(struct drm_gem_vram_object *gbo)
+{
+ ttm_bo_unreserve(&gbo->bo);
+}
+EXPORT_SYMBOL(drm_gem_vram_unreserve);
+
+/**
+ * drm_gem_vram_mmap_offset() - Returns a GEM VRAM object's mmap offset
+ * @gbo: the GEM VRAM object
+ *
+ * See drm_vma_node_offset_addr() for more information.
+ *
+ * Returns:
+ * The buffer object's offset for userspace mappings on success, or
+ * 0 if no offset is allocated.
+ */
+u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo)
+{
+ return drm_vma_node_offset_addr(&gbo->bo.vma_node);
+}
+EXPORT_SYMBOL(drm_gem_vram_mmap_offset);
+
+/**
+ * drm_gem_vram_offset() - \
+ Returns a GEM VRAM object's offset in video memory
+ * @gbo: the GEM VRAM object
+ *
+ * This function returns the buffer object's offset in the device's video
+ * memory. The buffer object has to be pinned to %TTM_PL_VRAM.
+ *
+ * Returns:
+ * The buffer object's offset in video memory on success, or
+ * a negative errno code otherwise.
+ */
+s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo)
+{
+ if (WARN_ON_ONCE(!gbo->pin_count))
+ return (s64)-ENODEV;
+ return gbo->bo.offset;
+}
+EXPORT_SYMBOL(drm_gem_vram_offset);
+
+/**
+ * drm_gem_vram_pin() - Pins a GEM VRAM object in a region.
+ * @gbo: the GEM VRAM object
+ * @pl_flag: a bitmask of possible memory regions
+ *
+ * Pinning a buffer object ensures that it is not evicted from
+ * a memory region. A pinned buffer object has to be unpinned before
+ * it can be pinned to another region.
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise.
+ */
+int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag)
+{
+ int i, ret;
+ struct ttm_operation_ctx ctx = { false, false };
+
+ if (gbo->pin_count) {
+ ++gbo->pin_count;
+ return 0;
+ }
+
+ drm_gem_vram_placement(gbo, pl_flag);
+ for (i = 0; i < gbo->placement.num_placement; ++i)
+ gbo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;
+
+ ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
+ if (ret < 0)
+ return ret;
+
+ gbo->pin_count = 1;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_gem_vram_pin);
+
+/**
+ * drm_gem_vram_unpin() - Unpins a GEM VRAM object
+ * @gbo: the GEM VRAM object
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise.
+ */
+int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo)
+{
+ int i, ret;
+ struct ttm_operation_ctx ctx = { false, false };
+
+ if (WARN_ON_ONCE(!gbo->pin_count))
+ return 0;
+
+ --gbo->pin_count;
+ if (gbo->pin_count)
+ return 0;
+
+ for (i = 0; i < gbo->placement.num_placement ; ++i)
+ gbo->placements[i].flags &= ~TTM_PL_FLAG_NO_EVICT;
+
+ ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_gem_vram_unpin);
+
+/**
+ * drm_gem_vram_push_to_system() - \
+ Unpins a GEM VRAM object and moves it to system memory
+ * @gbo: the GEM VRAM object
+ *
+ * This operation only works if the caller holds the final pin on the
+ * buffer object.
+ *
+ * Returns:
+ * 0 on success, or
+ * a negative error code otherwise.
+ */
+int drm_gem_vram_push_to_system(struct drm_gem_vram_object *gbo)
+{
+ int i, ret;
+ struct ttm_operation_ctx ctx = { false, false };
+
+ if (WARN_ON_ONCE(!gbo->pin_count))
+ return 0;
+
+ --gbo->pin_count;
+ if (gbo->pin_count)
+ return 0;
+
+ if (gbo->kmap.virtual)
+ ttm_bo_kunmap(&gbo->kmap);
+
+ drm_gem_vram_placement(gbo, TTM_PL_FLAG_SYSTEM);
+ for (i = 0; i < gbo->placement.num_placement ; ++i)
+ gbo->placements[i].flags |= TTM_PL_FLAG_NO_EVICT;
+
+ ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_gem_vram_push_to_system);
+
+/**
+ * drm_gem_vram_kmap_at() - Maps a GEM VRAM object into kernel address space
+ * @gbo: the GEM VRAM object
+ * @map: establish a mapping if necessary
+ * @is_iomem: returns true if the mapped memory is I/O memory, or false \
+ otherwise; can be NULL
+ * @kmap: the mapping's kmap object
+ *
+ * This function maps the buffer object into the kernel's address space
+ * or returns the current mapping. If the parameter map is false, the
+ * function only queries the current mapping, but does not establish a
+ * new one.
+ *
+ * Returns:
+ * The buffers virtual address if mapped, or
+ * NULL if not mapped, or
+ * an ERR_PTR()-encoded error code otherwise.
+ */
+void *drm_gem_vram_kmap_at(struct drm_gem_vram_object *gbo, bool map,
+ bool *is_iomem, struct ttm_bo_kmap_obj *kmap)
+{
+ int ret;
+
+ if (kmap->virtual || !map)
+ goto out;
+
+ ret = ttm_bo_kmap(&gbo->bo, 0, gbo->bo.num_pages, kmap);
+ if (ret)
+ return ERR_PTR(ret);
+
+out:
+ if (!is_iomem)
+ return kmap->virtual;
+ if (!kmap->virtual) {
+ *is_iomem = false;
+ return NULL;
+ }
+ return ttm_kmap_obj_virtual(kmap, is_iomem);
+}
+EXPORT_SYMBOL(drm_gem_vram_kmap_at);
+
+/**
+ * drm_gem_vram_kmap() - Maps a GEM VRAM object into kernel address space
+ * @gbo: the GEM VRAM object
+ * @map: establish a mapping if necessary
+ * @is_iomem: returns true if the mapped memory is I/O memory, or false \
+ otherwise; can be NULL
+ *
+ * This function maps the buffer object into the kernel's address space
+ * or returns the current mapping. If the parameter map is false, the
+ * function only queries the current mapping, but does not establish a
+ * new one.
+ *
+ * Returns:
+ * The buffers virtual address if mapped, or
+ * NULL if not mapped, or
+ * an ERR_PTR()-encoded error code otherwise.
+ */
+void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map,
+ bool *is_iomem)
+{
+ return drm_gem_vram_kmap_at(gbo, map, is_iomem, &gbo->kmap);
+}
+EXPORT_SYMBOL(drm_gem_vram_kmap);
+
+/**
+ * drm_gem_vram_kunmap_at() - Unmaps a GEM VRAM object
+ * @gbo: the GEM VRAM object
+ * @kmap: the mapping's kmap object
+ */
+void drm_gem_vram_kunmap_at(struct drm_gem_vram_object *gbo,
+ struct ttm_bo_kmap_obj *kmap)
+{
+ if (!kmap->virtual)
+ return;
+
+ ttm_bo_kunmap(kmap);
+ kmap->virtual = NULL;
+}
+EXPORT_SYMBOL(drm_gem_vram_kunmap_at);
+
+/**
+ * drm_gem_vram_kunmap() - Unmaps a GEM VRAM object
+ * @gbo: the GEM VRAM object
+ */
+void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo)
+{
+ drm_gem_vram_kunmap_at(gbo, &gbo->kmap);
+}
+EXPORT_SYMBOL(drm_gem_vram_kunmap);
diff --git a/drivers/gpu/drm/drm_vram_helper_common.c b/drivers/gpu/drm/drm_vram_helper_common.c
new file mode 100644
index 0000000000000000000000000000000000000000..7c25daca18d074ef80db82de8a87da788031ba76
--- /dev/null
+++ b/drivers/gpu/drm/drm_vram_helper_common.c
@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include <linux/module.h>
+
+MODULE_DESCRIPTION("DRM VRAM memory-management helpers");
+MODULE_LICENSE("GPL");
diff --git a/include/drm/drm_gem_vram_helper.h b/include/drm/drm_gem_vram_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..5802dd6949397ccdf957c9591943f9bfa352d254
--- /dev/null
+++ b/include/drm/drm_gem_vram_helper.h
@@ -0,0 +1,92 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef DRM_GEM_VRAM_HELPER_H
+#define DRM_GEM_VRAM_HELPER_H
+
+#include <drm/drm_gem.h>
+#include <drm/ttm/ttm_bo_api.h>
+#include <drm/ttm/ttm_placement.h>
+#include <linux/kernel.h> /* for container_of() */
+
+struct filp;
+
+#define DRM_GEM_VRAM_PL_FLAG_VRAM TTM_PL_FLAG_VRAM
+#define DRM_GEM_VRAM_PL_FLAG_SYSTEM TTM_PL_FLAG_SYSTEM
+
+/*
+ * Buffer-object helpers
+ */
+
+/**
+ * struct drm_gem_vram_object - GEM object backed by VRAM
+ * @gem: GEM object
+ * @bo: TTM buffer object
+ * @kmap: Mapping information for @bo
+ * @placement: TTM placement information. Supported placements are \
+ %TTM_PL_VRAM and %TTM_PL_SYSTEM
+ * @placements: TTM placement information.
+ * @pin_count: Pin counter
+ *
+ * The type struct drm_gem_vram_object represents a GEM object that is
+ * backed by VRAM. It can be used for simple framebuffer devices with
+ * dedicated memory. The buffer object can be evicted to system memory if
+ * video memory becomes scarce.
+ */
+struct drm_gem_vram_object {
+ struct drm_gem_object gem;
+ struct ttm_buffer_object bo;
+ struct ttm_bo_kmap_obj kmap;
+
+ /* Supported placements are %TTM_PL_VRAM and %TTM_PL_SYSTEM */
+ struct ttm_placement placement;
+ struct ttm_place placements[2];
+
+ int pin_count;
+};
+
+/**
+ * Returns the container of type &struct drm_gem_vram_object
+ * for field bo.
+ * @bo: the VRAM buffer object
+ * Returns: The containing GEM VRAM object
+ */
+static inline struct drm_gem_vram_object *drm_gem_vram_of_bo(
+ struct ttm_buffer_object *bo)
+{
+ return container_of(bo, struct drm_gem_vram_object, bo);
+}
+
+/**
+ * Returns the container of type &struct drm_gem_vram_object
+ * for field gem.
+ * @gem: the GEM object
+ * Returns: The containing GEM VRAM object
+ */
+static inline struct drm_gem_vram_object *drm_gem_vram_of_gem(
+ struct drm_gem_object *gem)
+{
+ return container_of(gem, struct drm_gem_vram_object, gem);
+}
+
+struct drm_gem_vram_object *drm_gem_vram_create(struct drm_device *dev,
+ struct ttm_bo_device *bdev,
+ size_t size,
+ unsigned long pg_align,
+ bool interruptible);
+void drm_gem_vram_put(struct drm_gem_vram_object *gbo);
+int drm_gem_vram_reserve(struct drm_gem_vram_object *gbo, bool no_wait);
+void drm_gem_vram_unreserve(struct drm_gem_vram_object *gbo);
+u64 drm_gem_vram_mmap_offset(struct drm_gem_vram_object *gbo);
+s64 drm_gem_vram_offset(struct drm_gem_vram_object *gbo);
+int drm_gem_vram_pin(struct drm_gem_vram_object *gbo, unsigned long pl_flag);
+int drm_gem_vram_unpin(struct drm_gem_vram_object *gbo);
+int drm_gem_vram_push_to_system(struct drm_gem_vram_object *gbo);
+void *drm_gem_vram_kmap_at(struct drm_gem_vram_object *gbo, bool map,
+ bool *is_iomem, struct ttm_bo_kmap_obj *kmap);
+void *drm_gem_vram_kmap(struct drm_gem_vram_object *gbo, bool map,
+ bool *is_iomem);
+void drm_gem_vram_kunmap_at(struct drm_gem_vram_object *gbo,
+ struct ttm_bo_kmap_obj *kmap);
+void drm_gem_vram_kunmap(struct drm_gem_vram_object *gbo);
+
+#endif