// SPDX-License-Identifier: GPL-2.0-or-later
#include <linux/iosys-map.h>
#include <linux/module.h>
#include <drm/drm_debugfs.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_gem_ttm_helper.h>
#include <drm/drm_gem_vram_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_mode.h>
#include <drm/drm_plane.h>
#include <drm/drm_prime.h>
#include <drm/drm_simple_kms_helper.h>
#include <drm/ttm/ttm_range_manager.h>
#include <drm/ttm/ttm_tt.h>
static const struct drm_gem_object_funcs drm_gem_vram_object_funcs;
/**
* DOC: overview
*
* This library provides &struct drm_gem_vram_object (GEM VRAM), a GEM
* buffer object that is backed by video RAM (VRAM). It can be used for
* framebuffer devices with dedicated memory.
*
* The data structure &struct drm_vram_mm and its helpers implement a memory
* manager for simple framebuffer devices with dedicated video memory. GEM
* VRAM buffer objects are either placed in the video memory or remain evicted
* to system memory.
*
* With the GEM interface userspace applications create, manage and destroy
* graphics buffers, such as an on-screen framebuffer. GEM does not provide
* an implementation of these interfaces. It's up to the DRM driver to
* provide an implementation that suits the hardware. If the hardware device
* contains dedicated video memory, the DRM driver can use the VRAM helper
* library. Each active buffer object is stored in video RAM. Active
* buffer are used for drawing the current frame, typically something like
* the frame's scanout buffer or the cursor image. If there's no more space
* left in VRAM, inactive GEM objects can be moved to system memory.
*
* To initialize the VRAM helper library call drmm_vram_helper_init().
* The function allocates and initializes an instance of &struct drm_vram_mm
* in &struct drm_device.vram_mm . Use &DRM_GEM_VRAM_DRIVER to initialize
* &struct drm_driver and &DRM_VRAM_MM_FILE_OPERATIONS to initialize
* &struct file_operations; as illustrated below.
*
* .. code-block:: c
*
* struct file_operations fops ={
* .owner = THIS_MODULE,
* DRM_VRAM_MM_FILE_OPERATION
* };
* struct drm_driver drv = {
* .driver_feature = DRM_ ... ,
* .fops = &fops,
* DRM_GEM_VRAM_DRIVER
* };
*
* int init_drm_driver()
* {
* struct drm_device *dev;
* uint64_t vram_base;
* unsigned long vram_size;
* int ret;
*
* // setup device, vram base and size
* // ...
*
* ret = drmm_vram_helper_init(dev, vram_base, vram_size);
* if (ret)
* return ret;
* return 0;
* }
*
* This creates an instance of &struct drm_vram_mm, exports DRM userspace
* interfaces for GEM buffer management and initializes file operations to
* allow for accessing created GEM buffers. With this setup, the DRM driver
* manages an area of video RAM with VRAM MM and provides GEM VRAM objects
* to userspace.
*
* You don't have to clean up the instance of VRAM MM.
* drmm_vram_helper_init() is a managed interface that installs a
* clean-up handler to run during the DRM device's release.
*
* For drawing or scanout operations, rsp. buffer objects have to be pinned
* in video RAM. Call drm_gem_vram_pin() with &DRM_GEM_VRAM_PL_FLAG_VRAM or
* &DRM_GEM_VRAM_PL_FLAG_SYSTEM to pin a buffer object in video RAM or system
* memory. Call drm_gem_vram_unpin() to release the pinned object afterwards.
*
* A buffer object that is pinned in video RAM has a fixed address within that
* memory region. Call drm_gem_vram_offset() to retrieve this value. Typically
* it's used to program the hardware's scanout engine for framebuffers, set
* the cursor overlay's image for a mouse cursor, or use it as input to the
* hardware's drawing engine.
*
* To access a buffer object's memory from the DRM driver, call
* drm_gem_vram_vmap(). It maps the buffer into kernel address
* space and returns the memory address. Use drm_gem_vram_vunmap() to
* release the mapping.
*/
/*
* 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.
*/
WARN_ON(gbo->vmap_use_count);
WARN_ON(iosys_map_is_set(&gbo->map));
drm_gem_object_release(&gbo->bo.base);
}
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)
{
u32 invariant_flags = 0;
unsigned int i;
unsigned int c = 0;
if (pl_flag & DRM_GEM_VRAM_PL_FLAG_TOPDOWN)
invariant_flags = TTM_PL_FLAG_TOPDOWN;
gbo->placement.placement = gbo->placements;
if (pl_flag & DRM_GEM_VRAM_PL_FLAG_VRAM) {
gbo->placements[c].mem_type = TTM_PL_VRAM;
gbo->placements[c++].flags = invariant_flags;
}
if (pl_flag & DRM_GEM_VRAM_PL_FLAG_SYSTEM || !c) {
gbo->placements[c].mem_type = TTM_PL_SYSTEM;
gbo->placements[c++].flags = invariant_flags;
}
gbo->placement.num_placement = c;
for (i = 0; i < c; ++i) {
gbo->placements[i].fpfn = 0;
gbo->placements[i].lpfn = 0;
}
}
/**
* drm_gem_vram_create() - Creates a VRAM-backed GEM object
* @dev: the DRM device
* @size: the buffer size in bytes
* @pg_align: the buffer's alignment in multiples of the page size
*
* GEM objects are allocated by calling struct drm_driver.gem_create_object,
* if set. Otherwise kzalloc() will be used. Drivers can set their own GEM
* object functions in struct drm_driver.gem_create_object. If no functions
* are set, the new GEM object will use the default functions from GEM VRAM
* helpers.
*
* 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,
size_t size,
unsigned long pg_align)
{
struct drm_gem_vram_object *gbo;
struct drm_gem_object *gem;
struct drm_vram_mm *vmm = dev->vram_mm;
struct ttm_device *bdev;
int ret;
if (WARN_ONCE(!vmm, "VRAM MM not initialized"))
return ERR_PTR(-EINVAL);
if (dev->driver->gem_create_object) {
gem = dev->driver->gem_create_object(dev, size);
if (IS_ERR(gem))
return ERR_CAST(gem);
gbo = drm_gem_vram_of_gem(gem);
} else {
gbo = kzalloc(sizeof(*gbo), GFP_KERNEL);
if (!gbo)
return ERR_PTR(-ENOMEM);
gem = &gbo->bo.base;
}
if (!gem->funcs)
gem->funcs = &drm_gem_vram_object_funcs;
ret = drm_gem_object_init(dev, gem, size);
if (ret) {
kfree(gbo);
return ERR_PTR(ret);
}
bdev = &vmm->bdev;
gbo->bo.bdev = bdev;
drm_gem_vram_placement(gbo, DRM_GEM_VRAM_PL_FLAG_SYSTEM);
/*
* A failing ttm_bo_init will call ttm_buffer_object_destroy
* to release gbo->bo.base and kfree gbo.
*/
ret = ttm_bo_init_validate(bdev, &gbo->bo, ttm_bo_type_device,
&gbo->placement, pg_align, false, NULL, NULL,
ttm_buffer_object_destroy);
if (ret)
return ERR_PTR(ret);
return gbo;
}
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);
static u64 drm_gem_vram_pg_offset(struct drm_gem_vram_object *gbo)
{
/* Keep TTM behavior for now, remove when drivers are audited */
if (WARN_ON_ONCE(!gbo->bo.resource ||
gbo->bo.resource->mem_type == TTM_PL_SYSTEM))
return 0;
return gbo->bo.resource->start;
}
/**
* 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->bo.pin_count))
return (s64)-ENODEV;
return drm_gem_vram_pg_offset(gbo) << PAGE_SHIFT;
}
EXPORT_SYMBOL(drm_gem_vram_offset);
static int drm_gem_vram_pin_locked(struct drm_gem_vram_object *gbo,
unsigned long pl_flag)
{
struct ttm_operation_ctx ctx = { false, false };
int ret;
dma_resv_assert_held(gbo->bo.base.resv);
if (gbo->bo.pin_count)
goto out;
if (pl_flag)
drm_gem_vram_placement(gbo, pl_flag);
ret = ttm_bo_validate(&gbo->bo, &gbo->placement, &ctx);
if (ret < 0)
return ret;
out:
ttm_bo_pin(&gbo->bo);
return 0;
}
/**
* 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. If the pl_flag argument is 0,
* the buffer is pinned at its current location (video RAM or system
* memory).
*
* Small buffer objects, such as cursor images, can lead to memory
* fragmentation if they are pinned in the middle of video RAM. This
* is especially a problem on devices with only a small amount of
* video RAM. Fragmentation can prevent the primary framebuffer from
* fitting in, even though there's enough memory overall. The modifier
* DRM_GEM_VRAM_PL_FLAG_TOPDOWN marks the buffer object to be pinned
* at the high end of the memory region to avoid fragmentation.
*
* 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 ret;
ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
if (ret)
return ret;
ret = drm_gem_vram_pin_locked(gbo, pl_flag);
ttm_bo_unreserve(&gbo->bo);
return ret;
}
EXPORT_SYMBOL(drm_gem_vram_pin);
static void drm_gem_vram_unpin_locked(struct drm_gem_vram_object *gbo)
{
dma_resv_assert_held(gbo->bo.base.resv);
ttm_bo_unpin(&gbo->bo);
}
/**
* 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 ret;
ret = ttm_bo_reserve(&gbo->bo, true, false, NULL);
if (ret)
return ret;
drm_gem_vram_unpin_locked(gbo);
ttm_bo_unreserve(&gbo->bo);
return 0;
}
EXPORT_SYMBOL(drm_gem_vram_unpin);
/**
* drm_gem_vram_vmap() - Pins and maps a GEM VRAM object into kernel address
* space
* @gbo: The GEM VRAM object to map
* @map: Returns the kernel virtual address of the VRAM GEM object's backing
* store.
*
* The vmap function pins a GEM VRAM object to its current location, either
* system or video memory, and maps its buffer into kernel address space.
* As pinned object cannot be relocated, you should avoid pinning objects
* permanently. Call drm_gem_vram_vunmap() with the returned address to
* unmap and unpin the GEM VRAM object.
*
* Returns:
* 0 on success, or a negative error code otherwise.
*/
int drm_gem_vram_vmap(struct drm_gem_vram_object *gbo, struct iosys_map *map)
{
int ret;
dma_resv_assert_held(gbo->bo.base.resv);
if (gbo->vmap_use_count > 0)
goto out;
/*
* VRAM helpers unmap the BO only on demand. So the previous
* page mapping might still be around. Only vmap if the there's
* no mapping present.
*/
if (iosys_map_is_null(&gbo->map)) {
ret = ttm_bo_vmap(&gbo->bo, &gbo->map);
if (ret)
return ret;
}
out:
++gbo->vmap_use_count;
*map = gbo->map;
return 0;
}
EXPORT_SYMBOL(drm_gem_vram_vmap);
/**
* drm_gem_vram_vunmap() - Unmaps and unpins a GEM VRAM object
* @gbo: The GEM VRAM object to unmap
* @map: Kernel virtual address where the VRAM GEM object was mapped
*
* A call to drm_gem_vram_vunmap() unmaps and unpins a GEM VRAM buffer. See
* the documentation for drm_gem_vram_vmap() for more information.
*/
void drm_gem_vram_vunmap(struct drm_gem_vram_object *gbo,
struct iosys_map *map)
{
struct drm_device *dev = gbo->bo.base.dev;
dma_resv_assert_held(gbo->bo.base.resv);
if (drm_WARN_ON_ONCE(dev, !gbo->vmap_use_count))
return;
if (drm_WARN_ON_ONCE(dev, !iosys_map_is_equal(&gbo->map, map)))
return; /* BUG: map not mapped from this BO */
if (--gbo->vmap_use_count > 0)
return;
/*
* Permanently mapping and unmapping buffers adds overhead from
* updating the page tables and creates debugging output. Therefore,
* we delay the actual unmap operation until the BO gets evicted
* from memory. See drm_gem_vram_bo_driver_move_notify().
*/
}
EXPORT_SYMBOL(drm_gem_vram_vunmap);
/**
* drm_gem_vram_fill_create_dumb() - Helper for implementing
* &struct drm_driver.dumb_create
*
* @file: the DRM file
* @dev: the DRM device
* @pg_align: the buffer's alignment in multiples of the page size
* @pitch_align: the scanline's alignment in powers of 2
* @args: the arguments as provided to
* &struct drm_driver.dumb_create
*
* This helper function fills &struct drm_mode_create_dumb, which is used
* by &struct drm_driver.dumb_create. Implementations of this interface
* should forwards their arguments to this helper, plus the driver-specific
* parameters.
*
* Returns:
* 0 on success, or
* a negative error code otherwise.
*/
int drm_gem_vram_fill_create_dumb(struct drm_file *file,
struct drm_device *dev,
unsigned long pg_align,
unsigned long pitch_align,
struct drm_mode_create_dumb *args)
{
size_t pitch, size;
struct drm_gem_vram_object *gbo;
int ret;
u32 handle;
pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
if (pitch_align) {
if (WARN_ON_ONCE(!is_power_of_2(pitch_align)))
return -EINVAL;
pitch = ALIGN(pitch, pitch_align);
}
size = pitch * args->height;
size = roundup(size, PAGE_SIZE);
if (!size)
return -EINVAL;
gbo = drm_gem_vram_create(dev, size, pg_align);
if (IS_ERR(gbo))
return PTR_ERR(gbo);
ret = drm_gem_handle_create(file, &gbo->bo.base, &handle);
if (ret)
goto err_drm_gem_object_put;
drm_gem_object_put(&gbo->bo.base);
args->pitch = pitch;
args->size = size;
args->handle = handle;
return 0;
err_drm_gem_object_put:
drm_gem_object_put(&gbo->bo.base);
return ret;
}
EXPORT_SYMBOL(drm_gem_vram_fill_create_dumb);
/*
* Helpers for struct ttm_device_funcs
*/
static bool drm_is_gem_vram(struct ttm_buffer_object *bo)
{
return (bo->destroy == ttm_buffer_object_destroy);
}
static void drm_gem_vram_bo_driver_evict_flags(struct drm_gem_vram_object *gbo,
struct ttm_placement *pl)
{
drm_gem_vram_placement(gbo, DRM_GEM_VRAM_PL_FLAG_SYSTEM);
*pl = gbo->placement;
}
static void drm_gem_vram_bo_driver_move_notify(struct drm_gem_vram_object *gbo)
{
struct ttm_buffer_object *bo = &gbo->bo;
struct drm_device *dev = bo->base.dev;
if (drm_WARN_ON_ONCE(dev, gbo->vmap_use_count))
return;
ttm_bo_vunmap(bo, &gbo->map);
iosys_map_clear(&gbo->map); /* explicitly clear mapping for next vmap call */
}
static int drm_gem_vram_bo_driver_move(struct drm_gem_vram_object *gbo,
bool evict,
struct ttm_operation_ctx *ctx,
struct ttm_resource *new_mem)
{
drm_gem_vram_bo_driver_move_notify(gbo);
return ttm_bo_move_memcpy(&gbo->bo, ctx, new_mem);
}
/*
* Helpers for struct drm_gem_object_funcs
*/
/**
* drm_gem_vram_object_free() - Implements &struct drm_gem_object_funcs.free
* @gem: GEM object. Refers to &struct drm_gem_vram_object.gem
*/
static void drm_gem_vram_object_free(struct drm_gem_object *gem)
{
struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
drm_gem_vram_put(gbo);
}
/*
* Helpers for dump buffers
*/
/**
* drm_gem_vram_driver_dumb_create() - Implements &struct drm_driver.dumb_create
* @file: the DRM file
* @dev: the DRM device
* @args: the arguments as provided to
* &struct drm_driver.dumb_create
*
* This function requires the driver to use @drm_device.vram_mm for its
* instance of VRAM MM.
*
* Returns:
* 0 on success, or
* a negative error code otherwise.
*/
int drm_gem_vram_driver_dumb_create(struct drm_file *file,
struct drm_device *dev,
struct drm_mode_create_dumb *args)
{
if (WARN_ONCE(!dev->vram_mm, "VRAM MM not initialized"))
return -EINVAL;
return drm_gem_vram_fill_create_dumb(file, dev, 0, 0, args);
}
EXPORT_SYMBOL(drm_gem_vram_driver_dumb_create);
/*
* Helpers for struct drm_plane_helper_funcs
*/
static void __drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
struct drm_plane_state *state,
unsigned int num_planes)
{
struct drm_gem_object *obj;
struct drm_gem_vram_object *gbo;
struct drm_framebuffer *fb = state->fb;
while (num_planes) {
--num_planes;
obj = drm_gem_fb_get_obj(fb, num_planes);
if (!obj)
continue;
gbo = drm_gem_vram_of_gem(obj);
drm_gem_vram_unpin(gbo);
}
}
/**
* drm_gem_vram_plane_helper_prepare_fb() - Implements &struct
* drm_plane_helper_funcs.prepare_fb
* @plane: a DRM plane
* @new_state: the plane's new state
*
* During plane updates, this function sets the plane's fence and
* pins the GEM VRAM objects of the plane's new framebuffer to VRAM.
* Call drm_gem_vram_plane_helper_cleanup_fb() to unpin them.
*
* Returns:
* 0 on success, or
* a negative errno code otherwise.
*/
int
drm_gem_vram_plane_helper_prepare_fb(struct drm_plane *plane,
struct drm_plane_state *new_state)
{
struct drm_framebuffer *fb = new_state->fb;
struct drm_gem_vram_object *gbo;
struct drm_gem_object *obj;
unsigned int i;
int ret;
if (!fb)
return 0;
for (i = 0; i < fb->format->num_planes; ++i) {
obj = drm_gem_fb_get_obj(fb, i);
if (!obj) {
ret = -EINVAL;
goto err_drm_gem_vram_unpin;
}
gbo = drm_gem_vram_of_gem(obj);
ret = drm_gem_vram_pin(gbo, DRM_GEM_VRAM_PL_FLAG_VRAM);
if (ret)
goto err_drm_gem_vram_unpin;
}
ret = drm_gem_plane_helper_prepare_fb(plane, new_state);
if (ret)
goto err_drm_gem_vram_unpin;
return 0;
err_drm_gem_vram_unpin:
__drm_gem_vram_plane_helper_cleanup_fb(plane, new_state, i);
return ret;
}
EXPORT_SYMBOL(drm_gem_vram_plane_helper_prepare_fb);
/**
* drm_gem_vram_plane_helper_cleanup_fb() - Implements &struct
* drm_plane_helper_funcs.cleanup_fb
* @plane: a DRM plane
* @old_state: the plane's old state
*
* During plane updates, this function unpins the GEM VRAM
* objects of the plane's old framebuffer from VRAM. Complements
* drm_gem_vram_plane_helper_prepare_fb().
*/
void
drm_gem_vram_plane_helper_cleanup_fb(struct drm_plane *plane,
struct drm_plane_state *old_state)
{
struct drm_framebuffer *fb = old_state->fb;
if (!fb)
return;
__drm_gem_vram_plane_helper_cleanup_fb(plane, old_state, fb->format->num_planes);
}
EXPORT_SYMBOL(drm_gem_vram_plane_helper_cleanup_fb);
/*
* Helpers for struct drm_simple_display_pipe_funcs
*/
/**
* drm_gem_vram_simple_display_pipe_prepare_fb() - Implements &struct
* drm_simple_display_pipe_funcs.prepare_fb
* @pipe: a simple display pipe
* @new_state: the plane's new state
*
* During plane updates, this function pins the GEM VRAM
* objects of the plane's new framebuffer to VRAM. Call
* drm_gem_vram_simple_display_pipe_cleanup_fb() to unpin them.
*
* Returns:
* 0 on success, or
* a negative errno code otherwise.
*/
int drm_gem_vram_simple_display_pipe_prepare_fb(
struct drm_simple_display_pipe *pipe,
struct drm_plane_state *new_state)
{
return drm_gem_vram_plane_helper_prepare_fb(&pipe->plane, new_state);
}
EXPORT_SYMBOL(drm_gem_vram_simple_display_pipe_prepare_fb);
/**
* drm_gem_vram_simple_display_pipe_cleanup_fb() - Implements &struct
* drm_simple_display_pipe_funcs.cleanup_fb
* @pipe: a simple display pipe
* @old_state: the plane's old state
*
* During plane updates, this function unpins the GEM VRAM
* objects of the plane's old framebuffer from VRAM. Complements
* drm_gem_vram_simple_display_pipe_prepare_fb().
*/
void drm_gem_vram_simple_display_pipe_cleanup_fb(
struct drm_simple_display_pipe *pipe,
struct drm_plane_state *old_state)
{
drm_gem_vram_plane_helper_cleanup_fb(&pipe->plane, old_state);
}
EXPORT_SYMBOL(drm_gem_vram_simple_display_pipe_cleanup_fb);
/*
* PRIME helpers
*/
/**
* drm_gem_vram_object_pin() - Implements &struct drm_gem_object_funcs.pin
* @gem: The GEM object to pin
*
* Returns:
* 0 on success, or
* a negative errno code otherwise.
*/
static int drm_gem_vram_object_pin(struct drm_gem_object *gem)
{
struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
/*
* Fbdev console emulation is the use case of these PRIME
* helpers. This may involve updating a hardware buffer from
* a shadow FB. We pin the buffer to it's current location
* (either video RAM or system memory) to prevent it from
* being relocated during the update operation. If you require
* the buffer to be pinned to VRAM, implement a callback that
* sets the flags accordingly.
*/
return drm_gem_vram_pin_locked(gbo, 0);
}
/**
* drm_gem_vram_object_unpin() - Implements &struct drm_gem_object_funcs.unpin
* @gem: The GEM object to unpin
*/
static void drm_gem_vram_object_unpin(struct drm_gem_object *gem)
{
struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
drm_gem_vram_unpin_locked(gbo);
}
/**
* drm_gem_vram_object_vmap() -
* Implements &struct drm_gem_object_funcs.vmap
* @gem: The GEM object to map
* @map: Returns the kernel virtual address of the VRAM GEM object's backing
* store.
*
* Returns:
* 0 on success, or a negative error code otherwise.
*/
static int drm_gem_vram_object_vmap(struct drm_gem_object *gem,
struct iosys_map *map)
{
struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
return drm_gem_vram_vmap(gbo, map);
}
/**
* drm_gem_vram_object_vunmap() -
* Implements &struct drm_gem_object_funcs.vunmap
* @gem: The GEM object to unmap
* @map: Kernel virtual address where the VRAM GEM object was mapped
*/
static void drm_gem_vram_object_vunmap(struct drm_gem_object *gem,
struct iosys_map *map)
{
struct drm_gem_vram_object *gbo = drm_gem_vram_of_gem(gem);
drm_gem_vram_vunmap(gbo, map);
}
/*
* GEM object funcs
*/
static const struct drm_gem_object_funcs drm_gem_vram_object_funcs = {
.free = drm_gem_vram_object_free,
.pin = drm_gem_vram_object_pin,
.unpin = drm_gem_vram_object_unpin,
.vmap = drm_gem_vram_object_vmap,
.vunmap = drm_gem_vram_object_vunmap,
.mmap = drm_gem_ttm_mmap,
.print_info = drm_gem_ttm_print_info,
};
/*
* VRAM memory manager
*/
/*
* TTM TT
*/
static void bo_driver_ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *tt)
{
ttm_tt_fini(tt);
kfree(tt);
}
/*
* 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;
ret = ttm_tt_init(tt, bo, page_flags, ttm_cached, 0);
if (ret < 0)
goto err_ttm_tt_init;
return tt;
err_ttm_tt_init:
kfree(tt);
return NULL;
}
static void bo_driver_evict_flags(struct ttm_buffer_object *bo,
struct ttm_placement *placement)
{
struct drm_gem_vram_object *gbo;
/* TTM may pass BOs that are not GEM VRAM BOs. */
if (!drm_is_gem_vram(bo))
return;
gbo = drm_gem_vram_of_bo(bo);
drm_gem_vram_bo_driver_evict_flags(gbo, placement);
}
static void bo_driver_delete_mem_notify(struct ttm_buffer_object *bo)
{
struct drm_gem_vram_object *gbo;
/* TTM may pass BOs that are not GEM VRAM BOs. */
if (!drm_is_gem_vram(bo))
return;
gbo = drm_gem_vram_of_bo(bo);
drm_gem_vram_bo_driver_move_notify(gbo);
}
static int bo_driver_move(struct ttm_buffer_object *bo,
bool evict,
struct ttm_operation_ctx *ctx,
struct ttm_resource *new_mem,
struct ttm_place *hop)
{
struct drm_gem_vram_object *gbo;
if (!bo->resource) {
if (new_mem->mem_type != TTM_PL_SYSTEM) {
hop->mem_type = TTM_PL_SYSTEM;
hop->flags = TTM_PL_FLAG_TEMPORARY;
return -EMULTIHOP;
}
ttm_bo_move_null(bo, new_mem);
return 0;
}
gbo = drm_gem_vram_of_bo(bo);
return drm_gem_vram_bo_driver_move(gbo, evict, ctx, new_mem);
}
static int bo_driver_io_mem_reserve(struct ttm_device *bdev,
struct ttm_resource *mem)
{
struct drm_vram_mm *vmm = drm_vram_mm_of_bdev(bdev);
switch (mem->mem_type) {
case TTM_PL_SYSTEM: /* nothing to do */
break;
case TTM_PL_VRAM:
mem->bus.offset = (mem->start << PAGE_SHIFT) + vmm->vram_base;
mem->bus.is_iomem = true;
mem->bus.caching = ttm_write_combined;
break;
default:
return -EINVAL;
}
return 0;
}
static struct ttm_device_funcs bo_driver = {
.ttm_tt_create = bo_driver_ttm_tt_create,
.ttm_tt_destroy = bo_driver_ttm_tt_destroy,
.eviction_valuable = ttm_bo_eviction_valuable,
.evict_flags = bo_driver_evict_flags,
.move = bo_driver_move,
.delete_mem_notify = bo_driver_delete_mem_notify,
.io_mem_reserve = bo_driver_io_mem_reserve,
};
/*
* struct drm_vram_mm
*/
static int drm_vram_mm_debugfs(struct seq_file *m, void *data)
{
struct drm_debugfs_entry *entry = m->private;
struct drm_vram_mm *vmm = entry->dev->vram_mm;
struct ttm_resource_manager *man = ttm_manager_type(&vmm->bdev, TTM_PL_VRAM);
struct drm_printer p = drm_seq_file_printer(m);
ttm_resource_manager_debug(man, &p);
return 0;
}
static const struct drm_debugfs_info drm_vram_mm_debugfs_list[] = {
{ "vram-mm", drm_vram_mm_debugfs, 0, NULL },
};
/**
* drm_vram_mm_debugfs_init() - Register VRAM MM debugfs file.
*
* @minor: drm minor device.
*
*/
void drm_vram_mm_debugfs_init(struct drm_minor *minor)
{
drm_debugfs_add_files(minor->dev, drm_vram_mm_debugfs_list,
ARRAY_SIZE(drm_vram_mm_debugfs_list));
}
EXPORT_SYMBOL(drm_vram_mm_debugfs_init);
static int drm_vram_mm_init(struct drm_vram_mm *vmm, struct drm_device *dev,
uint64_t vram_base, size_t vram_size)
{
int ret;
vmm->vram_base = vram_base;
vmm->vram_size = vram_size;
ret = ttm_device_init(&vmm->bdev, &bo_driver, dev->dev,
dev->anon_inode->i_mapping,
dev->vma_offset_manager,
false, true);
if (ret)
return ret;
ret = ttm_range_man_init(&vmm->bdev, TTM_PL_VRAM,
false, vram_size >> PAGE_SHIFT);
if (ret)
return ret;
return 0;
}
static void drm_vram_mm_cleanup(struct drm_vram_mm *vmm)
{
ttm_range_man_fini(&vmm->bdev, TTM_PL_VRAM);
ttm_device_fini(&vmm->bdev);
}
/*
* Helpers for integration with struct drm_device
*/
static struct drm_vram_mm *drm_vram_helper_alloc_mm(struct drm_device *dev, uint64_t vram_base,
size_t vram_size)
{
int ret;
if (WARN_ON(dev->vram_mm))
return dev->vram_mm;
dev->vram_mm = kzalloc(sizeof(*dev->vram_mm), GFP_KERNEL);
if (!dev->vram_mm)
return ERR_PTR(-ENOMEM);
ret = drm_vram_mm_init(dev->vram_mm, dev, vram_base, vram_size);
if (ret)
goto err_kfree;
return dev->vram_mm;
err_kfree:
kfree(dev->vram_mm);
dev->vram_mm = NULL;
return ERR_PTR(ret);
}
static void drm_vram_helper_release_mm(struct drm_device *dev)
{
if (!dev->vram_mm)
return;
drm_vram_mm_cleanup(dev->vram_mm);
kfree(dev->vram_mm);
dev->vram_mm = NULL;
}
static void drm_vram_mm_release(struct drm_device *dev, void *ptr)
{
drm_vram_helper_release_mm(dev);
}
/**
* drmm_vram_helper_init - Initializes a device's instance of
* &struct drm_vram_mm
* @dev: the DRM device
* @vram_base: the base address of the video memory
* @vram_size: the size of the video memory in bytes
*
* Creates a new instance of &struct drm_vram_mm and stores it in
* struct &drm_device.vram_mm. The instance is auto-managed and cleaned
* up as part of device cleanup. Calling this function multiple times
* will generate an error message.
*
* Returns:
* 0 on success, or a negative errno code otherwise.
*/
int drmm_vram_helper_init(struct drm_device *dev, uint64_t vram_base,
size_t vram_size)
{
struct drm_vram_mm *vram_mm;
if (drm_WARN_ON_ONCE(dev, dev->vram_mm))
return 0;
vram_mm = drm_vram_helper_alloc_mm(dev, vram_base, vram_size);
if (IS_ERR(vram_mm))
return PTR_ERR(vram_mm);
return drmm_add_action_or_reset(dev, drm_vram_mm_release, NULL);
}
EXPORT_SYMBOL(drmm_vram_helper_init);
/*
* Mode-config helpers
*/
static enum drm_mode_status
drm_vram_helper_mode_valid_internal(struct drm_device *dev,
const struct drm_display_mode *mode,
unsigned long max_bpp)
{
struct drm_vram_mm *vmm = dev->vram_mm;
unsigned long fbsize, fbpages, max_fbpages;
if (WARN_ON(!dev->vram_mm))
return MODE_BAD;
max_fbpages = (vmm->vram_size / 2) >> PAGE_SHIFT;
fbsize = mode->hdisplay * mode->vdisplay * max_bpp;
fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE);
if (fbpages > max_fbpages)
return MODE_MEM;
return MODE_OK;
}
/**
* drm_vram_helper_mode_valid - Tests if a display mode's
* framebuffer fits into the available video memory.
* @dev: the DRM device
* @mode: the mode to test
*
* This function tests if enough video memory is available for using the
* specified display mode. Atomic modesetting requires importing the
* designated framebuffer into video memory before evicting the active
* one. Hence, any framebuffer may consume at most half of the available
* VRAM. Display modes that require a larger framebuffer can not be used,
* even if the CRTC does support them. Each framebuffer is assumed to
* have 32-bit color depth.
*
* Note:
* The function can only test if the display mode is supported in
* general. If there are too many framebuffers pinned to video memory,
* a display mode may still not be usable in practice. The color depth of
* 32-bit fits all current use case. A more flexible test can be added
* when necessary.
*
* Returns:
* MODE_OK if the display mode is supported, or an error code of type
* enum drm_mode_status otherwise.
*/
enum drm_mode_status
drm_vram_helper_mode_valid(struct drm_device *dev,
const struct drm_display_mode *mode)
{
static const unsigned long max_bpp = 4; /* DRM_FORMAT_XRGB8888 */
return drm_vram_helper_mode_valid_internal(dev, mode, max_bpp);
}
EXPORT_SYMBOL(drm_vram_helper_mode_valid);
MODULE_DESCRIPTION("DRM VRAM memory-management helpers");
MODULE_LICENSE("GPL");
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