xref: /openbmc/linux/drivers/gpu/drm/msm/msm_fbdev.c (revision 842ed298)
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_gem.h"
13 #include "msm_kms.h"
14 
15 extern int msm_gem_mmap_obj(struct drm_gem_object *obj,
16 					struct vm_area_struct *vma);
17 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma);
18 
19 /*
20  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
21  */
22 
23 #define to_msm_fbdev(x) container_of(x, struct msm_fbdev, base)
24 
25 struct msm_fbdev {
26 	struct drm_fb_helper base;
27 	struct drm_framebuffer *fb;
28 };
29 
30 static const struct fb_ops msm_fb_ops = {
31 	.owner = THIS_MODULE,
32 	DRM_FB_HELPER_DEFAULT_OPS,
33 
34 	/* Note: to properly handle manual update displays, we wrap the
35 	 * basic fbdev ops which write to the framebuffer
36 	 */
37 	.fb_read = drm_fb_helper_sys_read,
38 	.fb_write = drm_fb_helper_sys_write,
39 	.fb_fillrect = drm_fb_helper_sys_fillrect,
40 	.fb_copyarea = drm_fb_helper_sys_copyarea,
41 	.fb_imageblit = drm_fb_helper_sys_imageblit,
42 	.fb_mmap = msm_fbdev_mmap,
43 };
44 
45 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
46 {
47 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
48 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
49 	struct drm_gem_object *bo = msm_framebuffer_bo(fbdev->fb, 0);
50 	int ret = 0;
51 
52 	ret = drm_gem_mmap_obj(bo, bo->size, vma);
53 	if (ret) {
54 		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
55 		return ret;
56 	}
57 
58 	return msm_gem_mmap_obj(bo, vma);
59 }
60 
61 static int msm_fbdev_create(struct drm_fb_helper *helper,
62 		struct drm_fb_helper_surface_size *sizes)
63 {
64 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
65 	struct drm_device *dev = helper->dev;
66 	struct msm_drm_private *priv = dev->dev_private;
67 	struct drm_framebuffer *fb = NULL;
68 	struct drm_gem_object *bo;
69 	struct fb_info *fbi = NULL;
70 	uint64_t paddr;
71 	uint32_t format;
72 	int ret, pitch;
73 
74 	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
75 
76 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
77 			sizes->surface_height, sizes->surface_bpp,
78 			sizes->fb_width, sizes->fb_height);
79 
80 	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
81 	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
82 			sizes->surface_height, pitch, format);
83 
84 	if (IS_ERR(fb)) {
85 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
86 		return PTR_ERR(fb);
87 	}
88 
89 	bo = msm_framebuffer_bo(fb, 0);
90 
91 	mutex_lock(&dev->struct_mutex);
92 
93 	/*
94 	 * NOTE: if we can be guaranteed to be able to map buffer
95 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
96 	 * buffer now:
97 	 */
98 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
99 	if (ret) {
100 		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
101 		goto fail_unlock;
102 	}
103 
104 	fbi = drm_fb_helper_alloc_fbi(helper);
105 	if (IS_ERR(fbi)) {
106 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
107 		ret = PTR_ERR(fbi);
108 		goto fail_unlock;
109 	}
110 
111 	DBG("fbi=%p, dev=%p", fbi, dev);
112 
113 	fbdev->fb = fb;
114 	helper->fb = fb;
115 
116 	fbi->fbops = &msm_fb_ops;
117 
118 	drm_fb_helper_fill_info(fbi, helper, sizes);
119 
120 	dev->mode_config.fb_base = paddr;
121 
122 	fbi->screen_base = msm_gem_get_vaddr(bo);
123 	if (IS_ERR(fbi->screen_base)) {
124 		ret = PTR_ERR(fbi->screen_base);
125 		goto fail_unlock;
126 	}
127 	fbi->screen_size = bo->size;
128 	fbi->fix.smem_start = paddr;
129 	fbi->fix.smem_len = bo->size;
130 
131 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
132 	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
133 
134 	mutex_unlock(&dev->struct_mutex);
135 
136 	return 0;
137 
138 fail_unlock:
139 	mutex_unlock(&dev->struct_mutex);
140 	drm_framebuffer_remove(fb);
141 	return ret;
142 }
143 
144 static const struct drm_fb_helper_funcs msm_fb_helper_funcs = {
145 	.fb_probe = msm_fbdev_create,
146 };
147 
148 /* initialize fbdev helper */
149 struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
150 {
151 	struct msm_drm_private *priv = dev->dev_private;
152 	struct msm_fbdev *fbdev = NULL;
153 	struct drm_fb_helper *helper;
154 	int ret;
155 
156 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
157 	if (!fbdev)
158 		goto fail;
159 
160 	helper = &fbdev->base;
161 
162 	drm_fb_helper_prepare(dev, helper, &msm_fb_helper_funcs);
163 
164 	ret = drm_fb_helper_init(dev, helper);
165 	if (ret) {
166 		DRM_DEV_ERROR(dev->dev, "could not init fbdev: ret=%d\n", ret);
167 		goto fail;
168 	}
169 
170 	/* the fw fb could be anywhere in memory */
171 	drm_fb_helper_remove_conflicting_framebuffers(NULL, "msm", false);
172 
173 	ret = drm_fb_helper_initial_config(helper, 32);
174 	if (ret)
175 		goto fini;
176 
177 	priv->fbdev = helper;
178 
179 	return helper;
180 
181 fini:
182 	drm_fb_helper_fini(helper);
183 fail:
184 	kfree(fbdev);
185 	return NULL;
186 }
187 
188 void msm_fbdev_free(struct drm_device *dev)
189 {
190 	struct msm_drm_private *priv = dev->dev_private;
191 	struct drm_fb_helper *helper = priv->fbdev;
192 	struct msm_fbdev *fbdev;
193 
194 	DBG();
195 
196 	drm_fb_helper_unregister_fbi(helper);
197 
198 	drm_fb_helper_fini(helper);
199 
200 	fbdev = to_msm_fbdev(priv->fbdev);
201 
202 	/* this will free the backing object */
203 	if (fbdev->fb) {
204 		struct drm_gem_object *bo =
205 			msm_framebuffer_bo(fbdev->fb, 0);
206 		msm_gem_put_vaddr(bo);
207 		drm_framebuffer_remove(fbdev->fb);
208 	}
209 
210 	kfree(fbdev);
211 
212 	priv->fbdev = NULL;
213 }
214