1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2013 Red Hat
  4 * Author: Rob Clark <robdclark@gmail.com>
  5 */
  6
  7#include <drm/drm_crtc.h>
  8#include <drm/drm_fb_helper.h>
  9#include <drm/drm_fourcc.h>
 10
 11#include "msm_drv.h"
 12#include "msm_kms.h"
 13
 14extern int msm_gem_mmap_obj(struct drm_gem_object *obj,
 15					struct vm_area_struct *vma);
 16static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma);
 17
 18/*
 19 * fbdev funcs, to implement legacy fbdev interface on top of drm driver
 20 */
 21
 22#define to_msm_fbdev(x) container_of(x, struct msm_fbdev, base)
 23
 24struct msm_fbdev {
 25	struct drm_fb_helper base;
 26	struct drm_framebuffer *fb;
 27};
 28
 29static const struct fb_ops msm_fb_ops = {
 30	.owner = THIS_MODULE,
 31	DRM_FB_HELPER_DEFAULT_OPS,
 32
 33	/* Note: to properly handle manual update displays, we wrap the
 34	 * basic fbdev ops which write to the framebuffer
 35	 */
 36	.fb_read = drm_fb_helper_sys_read,
 37	.fb_write = drm_fb_helper_sys_write,
 38	.fb_fillrect = drm_fb_helper_sys_fillrect,
 39	.fb_copyarea = drm_fb_helper_sys_copyarea,
 40	.fb_imageblit = drm_fb_helper_sys_imageblit,
 41	.fb_mmap = msm_fbdev_mmap,
 42};
 43
 44static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
 45{
 46	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
 47	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
 48	struct drm_gem_object *bo = msm_framebuffer_bo(fbdev->fb, 0);
 49	int ret = 0;
 50
 51	ret = drm_gem_mmap_obj(bo, bo->size, vma);
 52	if (ret) {
 53		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
 54		return ret;
 55	}
 56
 57	return msm_gem_mmap_obj(bo, vma);
 58}
 59
 60static int msm_fbdev_create(struct drm_fb_helper *helper,
 61		struct drm_fb_helper_surface_size *sizes)
 62{
 63	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
 64	struct drm_device *dev = helper->dev;
 65	struct msm_drm_private *priv = dev->dev_private;
 66	struct drm_framebuffer *fb = NULL;
 67	struct drm_gem_object *bo;
 68	struct fb_info *fbi = NULL;
 69	uint64_t paddr;
 70	uint32_t format;
 71	int ret, pitch;
 72
 73	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
 74
 75	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
 76			sizes->surface_height, sizes->surface_bpp,
 77			sizes->fb_width, sizes->fb_height);
 78
 79	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
 80	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
 81			sizes->surface_height, pitch, format);
 82
 83	if (IS_ERR(fb)) {
 84		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
 85		return PTR_ERR(fb);
 86	}
 87
 88	bo = msm_framebuffer_bo(fb, 0);
 89
 90	mutex_lock(&dev->struct_mutex);
 91
 92	/*
 93	 * NOTE: if we can be guaranteed to be able to map buffer
 94	 * in panic (ie. lock-safe, etc) we could avoid pinning the
 95	 * buffer now:
 96	 */
 97	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
 98	if (ret) {
 99		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
100		goto fail_unlock;
101	}
102
103	fbi = drm_fb_helper_alloc_fbi(helper);
104	if (IS_ERR(fbi)) {
105		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
106		ret = PTR_ERR(fbi);
107		goto fail_unlock;
108	}
109
110	DBG("fbi=%p, dev=%p", fbi, dev);
111
112	fbdev->fb = fb;
113	helper->fb = fb;
114
115	fbi->fbops = &msm_fb_ops;
116
117	drm_fb_helper_fill_info(fbi, helper, sizes);
118
119	dev->mode_config.fb_base = paddr;
120
121	fbi->screen_base = msm_gem_get_vaddr(bo);
122	if (IS_ERR(fbi->screen_base)) {
123		ret = PTR_ERR(fbi->screen_base);
124		goto fail_unlock;
125	}
126	fbi->screen_size = bo->size;
127	fbi->fix.smem_start = paddr;
128	fbi->fix.smem_len = bo->size;
129
130	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
131	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
132
133	mutex_unlock(&dev->struct_mutex);
134
135	return 0;
136
137fail_unlock:
138	mutex_unlock(&dev->struct_mutex);
139	drm_framebuffer_remove(fb);
140	return ret;
141}
142
143static const struct drm_fb_helper_funcs msm_fb_helper_funcs = {
144	.fb_probe = msm_fbdev_create,
145};
146
147/* initialize fbdev helper */
148struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
149{
150	struct msm_drm_private *priv = dev->dev_private;
151	struct msm_fbdev *fbdev = NULL;
152	struct drm_fb_helper *helper;
153	int ret;
154
155	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
156	if (!fbdev)
157		goto fail;
158
159	helper = &fbdev->base;
160
161	drm_fb_helper_prepare(dev, helper, &msm_fb_helper_funcs);
162
163	ret = drm_fb_helper_init(dev, helper);
164	if (ret) {
165		DRM_DEV_ERROR(dev->dev, "could not init fbdev: ret=%d\n", ret);
166		goto fail;
167	}
168
169	/* the fw fb could be anywhere in memory */
170	drm_fb_helper_remove_conflicting_framebuffers(NULL, "msm", false);
171
172	ret = drm_fb_helper_initial_config(helper, 32);
173	if (ret)
174		goto fini;
175
176	priv->fbdev = helper;
177
178	return helper;
179
180fini:
181	drm_fb_helper_fini(helper);
182fail:
183	kfree(fbdev);
184	return NULL;
185}
186
187void msm_fbdev_free(struct drm_device *dev)
188{
189	struct msm_drm_private *priv = dev->dev_private;
190	struct drm_fb_helper *helper = priv->fbdev;
191	struct msm_fbdev *fbdev;
192
193	DBG();
194
195	drm_fb_helper_unregister_fbi(helper);
196
197	drm_fb_helper_fini(helper);
198
199	fbdev = to_msm_fbdev(priv->fbdev);
200
201	/* this will free the backing object */
202	if (fbdev->fb) {
203		struct drm_gem_object *bo =
204			msm_framebuffer_bo(fbdev->fb, 0);
205		msm_gem_put_vaddr(bo);
206		drm_framebuffer_remove(fbdev->fb);
207	}
208
209	kfree(fbdev);
210
211	priv->fbdev = NULL;
212}