xref: /openbmc/linux/drivers/gpu/drm/msm/msm_fbdev.c (revision e481ff3f)
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_aperture.h>
8 #include <drm/drm_crtc.h>
9 #include <drm/drm_fb_helper.h>
10 #include <drm/drm_fourcc.h>
11 
12 #include "msm_drv.h"
13 #include "msm_gem.h"
14 #include "msm_kms.h"
15 
16 extern int msm_gem_mmap_obj(struct drm_gem_object *obj,
17 					struct vm_area_struct *vma);
18 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma);
19 
20 /*
21  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
22  */
23 
24 #define to_msm_fbdev(x) container_of(x, struct msm_fbdev, base)
25 
26 struct msm_fbdev {
27 	struct drm_fb_helper base;
28 	struct drm_framebuffer *fb;
29 };
30 
31 static const struct fb_ops msm_fb_ops = {
32 	.owner = THIS_MODULE,
33 	DRM_FB_HELPER_DEFAULT_OPS,
34 
35 	/* Note: to properly handle manual update displays, we wrap the
36 	 * basic fbdev ops which write to the framebuffer
37 	 */
38 	.fb_read = drm_fb_helper_sys_read,
39 	.fb_write = drm_fb_helper_sys_write,
40 	.fb_fillrect = drm_fb_helper_sys_fillrect,
41 	.fb_copyarea = drm_fb_helper_sys_copyarea,
42 	.fb_imageblit = drm_fb_helper_sys_imageblit,
43 	.fb_mmap = msm_fbdev_mmap,
44 };
45 
46 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
47 {
48 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
49 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
50 	struct drm_gem_object *bo = msm_framebuffer_bo(fbdev->fb, 0);
51 	int ret = 0;
52 
53 	ret = drm_gem_mmap_obj(bo, bo->size, vma);
54 	if (ret) {
55 		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
56 		return ret;
57 	}
58 
59 	return msm_gem_mmap_obj(bo, vma);
60 }
61 
62 static int msm_fbdev_create(struct drm_fb_helper *helper,
63 		struct drm_fb_helper_surface_size *sizes)
64 {
65 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
66 	struct drm_device *dev = helper->dev;
67 	struct msm_drm_private *priv = dev->dev_private;
68 	struct drm_framebuffer *fb = NULL;
69 	struct drm_gem_object *bo;
70 	struct fb_info *fbi = NULL;
71 	uint64_t paddr;
72 	uint32_t format;
73 	int ret, pitch;
74 
75 	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
76 
77 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
78 			sizes->surface_height, sizes->surface_bpp,
79 			sizes->fb_width, sizes->fb_height);
80 
81 	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
82 	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
83 			sizes->surface_height, pitch, format);
84 
85 	if (IS_ERR(fb)) {
86 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
87 		return PTR_ERR(fb);
88 	}
89 
90 	bo = msm_framebuffer_bo(fb, 0);
91 
92 	mutex_lock(&dev->struct_mutex);
93 
94 	/*
95 	 * NOTE: if we can be guaranteed to be able to map buffer
96 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
97 	 * buffer now:
98 	 */
99 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
100 	if (ret) {
101 		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
102 		goto fail_unlock;
103 	}
104 
105 	fbi = drm_fb_helper_alloc_fbi(helper);
106 	if (IS_ERR(fbi)) {
107 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
108 		ret = PTR_ERR(fbi);
109 		goto fail_unlock;
110 	}
111 
112 	DBG("fbi=%p, dev=%p", fbi, dev);
113 
114 	fbdev->fb = fb;
115 	helper->fb = fb;
116 
117 	fbi->fbops = &msm_fb_ops;
118 
119 	drm_fb_helper_fill_info(fbi, helper, sizes);
120 
121 	dev->mode_config.fb_base = paddr;
122 
123 	fbi->screen_base = msm_gem_get_vaddr(bo);
124 	if (IS_ERR(fbi->screen_base)) {
125 		ret = PTR_ERR(fbi->screen_base);
126 		goto fail_unlock;
127 	}
128 	fbi->screen_size = bo->size;
129 	fbi->fix.smem_start = paddr;
130 	fbi->fix.smem_len = bo->size;
131 
132 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
133 	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
134 
135 	mutex_unlock(&dev->struct_mutex);
136 
137 	return 0;
138 
139 fail_unlock:
140 	mutex_unlock(&dev->struct_mutex);
141 	drm_framebuffer_remove(fb);
142 	return ret;
143 }
144 
145 static const struct drm_fb_helper_funcs msm_fb_helper_funcs = {
146 	.fb_probe = msm_fbdev_create,
147 };
148 
149 /* initialize fbdev helper */
150 struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
151 {
152 	struct msm_drm_private *priv = dev->dev_private;
153 	struct msm_fbdev *fbdev = NULL;
154 	struct drm_fb_helper *helper;
155 	int ret;
156 
157 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
158 	if (!fbdev)
159 		goto fail;
160 
161 	helper = &fbdev->base;
162 
163 	drm_fb_helper_prepare(dev, helper, &msm_fb_helper_funcs);
164 
165 	ret = drm_fb_helper_init(dev, helper);
166 	if (ret) {
167 		DRM_DEV_ERROR(dev->dev, "could not init fbdev: ret=%d\n", ret);
168 		goto fail;
169 	}
170 
171 	/* the fw fb could be anywhere in memory */
172 	ret = drm_aperture_remove_framebuffers(false, "msm");
173 	if (ret)
174 		goto fini;
175 
176 	ret = drm_fb_helper_initial_config(helper, 32);
177 	if (ret)
178 		goto fini;
179 
180 	priv->fbdev = helper;
181 
182 	return helper;
183 
184 fini:
185 	drm_fb_helper_fini(helper);
186 fail:
187 	kfree(fbdev);
188 	return NULL;
189 }
190 
191 void msm_fbdev_free(struct drm_device *dev)
192 {
193 	struct msm_drm_private *priv = dev->dev_private;
194 	struct drm_fb_helper *helper = priv->fbdev;
195 	struct msm_fbdev *fbdev;
196 
197 	DBG();
198 
199 	drm_fb_helper_unregister_fbi(helper);
200 
201 	drm_fb_helper_fini(helper);
202 
203 	fbdev = to_msm_fbdev(priv->fbdev);
204 
205 	/* this will free the backing object */
206 	if (fbdev->fb) {
207 		struct drm_gem_object *bo =
208 			msm_framebuffer_bo(fbdev->fb, 0);
209 		msm_gem_put_vaddr(bo);
210 		drm_framebuffer_remove(fbdev->fb);
211 	}
212 
213 	kfree(fbdev);
214 
215 	priv->fbdev = NULL;
216 }
217