drm/vram-helpers: Merge code into a single file (b22b51a0) · Commits · EulixOS / Software / Kernel

Documentation/gpu/drm-mm.rst

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		@@ -373,15 +373,6 @@ GEM CMA Helper Functions Reference
		.. kernel-doc:: drivers/gpu/drm/drm_gem_cma_helper.c
		:export:

		VRAM Helper Function Reference
		==============================

		.. kernel-doc:: drivers/gpu/drm/drm_vram_helper_common.c
		:doc: overview

		.. kernel-doc:: include/drm/drm_gem_vram_helper.h
		:internal:

		GEM VRAM Helper Functions Reference
		-----------------------------------

drivers/gpu/drm/Makefile

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		@@ -33,8 +33,7 @@ drm-$(CONFIG_PCI) += drm_pci.o
		drm-$(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
		drm_vram_helper-y := drm_gem_vram_helper.o
		obj-$(CONFIG_DRM_VRAM_HELPER) += drm_vram_helper.o

		drm_ttm_helper-y := drm_gem_ttm_helper.o

drivers/gpu/drm/drm_gem_vram_helper.c

+90 −5

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		// SPDX-License-Identifier: GPL-2.0-or-later

		#include <linux/module.h>

		#include <drm/drm_debugfs.h>
		#include <drm/drm_device.h>
		#include <drm/drm_drv.h>
		@@ -19,13 +21,93 @@ static const struct drm_gem_object_funcs drm_gem_vram_object_funcs;
		/**
		* 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.
		* 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. Buffer
		* objects are either placed in video RAM or evicted to system memory. The rsp.
		* buffer object is provided by &struct drm_gem_vram_object.
		* 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.
		*
		* The easiest way to use the VRAM helper library is to call
		* drm_vram_helper_alloc_mm(). 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 = drm_vram_helper_alloc_mm(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.
		*
		* To clean up the VRAM memory management, call drm_vram_helper_release_mm()
		* in the driver's clean-up code.
		*
		* .. code-block:: c
		*
		* void fini_drm_driver()
		* {
		* struct drm_device *dev = ...;
		*
		* drm_vram_helper_release_mm(dev);
		* }
		*
		* For drawing or scanout operations, buffer object 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 draing engine.
		*
		* To access a buffer object's memory from the DRM driver, call
		* drm_gem_vram_kmap(). It (optionally) maps the buffer into kernel address
		* space and returns the memory address. Use drm_gem_vram_kunmap() to
		* release the mapping.
		*/

		/*
		@@ -1197,3 +1279,6 @@ drm_vram_helper_mode_valid(struct drm_device *dev,
		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");

drivers/gpu/drm/drm_vram_helper_common.c

deleted100644 → 0

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		// SPDX-License-Identifier: GPL-2.0-or-later

		#include <linux/module.h>

		/**
		* DOC: overview
		*
		* This library provides &struct drm_gem_vram_object (GEM VRAM), a GEM
		* buffer object that is backed by video RAM. It can be used for
		* framebuffer devices with dedicated memory. The video RAM is managed
		* by &struct drm_vram_mm (VRAM MM).
		*
		* 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.
		*
		* The easiest way to use the VRAM helper library is to call
		* drm_vram_helper_alloc_mm(). 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 = drm_vram_helper_alloc_mm(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.
		*
		* To clean up the VRAM memory management, call drm_vram_helper_release_mm()
		* in the driver's clean-up code.
		*
		* .. code-block:: c
		*
		* void fini_drm_driver()
		* {
		* struct drm_device *dev = ...;
		*
		* drm_vram_helper_release_mm(dev);
		* }
		*
		* For drawing or scanout operations, buffer object 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 draing engine.
		*
		* To access a buffer object's memory from the DRM driver, call
		* drm_gem_vram_kmap(). It (optionally) maps the buffer into kernel address
		* space and returns the memory address. Use drm_gem_vram_kunmap() to
		* release the mapping.
		*/

		MODULE_DESCRIPTION("DRM VRAM memory-management helpers");
		MODULE_LICENSE("GPL");