drm/vram-helpers: Merge code into a single file

Most of the documentation was in an otherwise empty file, which was
probably just left from a previous clean-up effort. So move code and
documentation into a single file.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200331081238.24749-1-tzimmermann@suse.de

1 files changed, 0 insertions, 94 deletions

diff --git a/drivers/gpu/drm/drm_vram_helper_common.c b/drivers/gpu/drm/drm_vram_helper_common.c
deleted file mode 100644
index 2000d9b33fd5..000000000000
--- a/drivers/gpu/drm/drm_vram_helper_common.c
+++ /dev/null
@@ -1,94 +0,0 @@
-// 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");