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 #include <drm/drm_prime.h>
12 
13 #include "msm_drv.h"
14 #include "msm_gem.h"
15 #include "msm_kms.h"
16 
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 
msm_fbdev_mmap(struct fb_info * info,struct vm_area_struct * vma)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 
51 	return drm_gem_prime_mmap(bo, vma);
52 }
53 
msm_fbdev_create(struct drm_fb_helper * helper,struct drm_fb_helper_surface_size * sizes)54 static int msm_fbdev_create(struct drm_fb_helper *helper,
55 		struct drm_fb_helper_surface_size *sizes)
56 {
57 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
58 	struct drm_device *dev = helper->dev;
59 	struct msm_drm_private *priv = dev->dev_private;
60 	struct drm_framebuffer *fb = NULL;
61 	struct drm_gem_object *bo;
62 	struct fb_info *fbi = NULL;
63 	uint64_t paddr;
64 	uint32_t format;
65 	int ret, pitch;
66 
67 	format = drm_mode_legacy_fb_format(sizes->surface_bpp, sizes->surface_depth);
68 
69 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
70 			sizes->surface_height, sizes->surface_bpp,
71 			sizes->fb_width, sizes->fb_height);
72 
73 	pitch = align_pitch(sizes->surface_width, sizes->surface_bpp);
74 	fb = msm_alloc_stolen_fb(dev, sizes->surface_width,
75 			sizes->surface_height, pitch, format);
76 
77 	if (IS_ERR(fb)) {
78 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb\n");
79 		return PTR_ERR(fb);
80 	}
81 
82 	bo = msm_framebuffer_bo(fb, 0);
83 
84 	mutex_lock(&dev->struct_mutex);
85 
86 	/*
87 	 * NOTE: if we can be guaranteed to be able to map buffer
88 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
89 	 * buffer now:
90 	 */
91 	ret = msm_gem_get_and_pin_iova(bo, priv->kms->aspace, &paddr);
92 	if (ret) {
93 		DRM_DEV_ERROR(dev->dev, "failed to get buffer obj iova: %d\n", ret);
94 		goto fail_unlock;
95 	}
96 
97 	fbi = drm_fb_helper_alloc_fbi(helper);
98 	if (IS_ERR(fbi)) {
99 		DRM_DEV_ERROR(dev->dev, "failed to allocate fb info\n");
100 		ret = PTR_ERR(fbi);
101 		goto fail_unlock;
102 	}
103 
104 	DBG("fbi=%p, dev=%p", fbi, dev);
105 
106 	fbdev->fb = fb;
107 	helper->fb = fb;
108 
109 	fbi->fbops = &msm_fb_ops;
110 
111 	drm_fb_helper_fill_info(fbi, helper, sizes);
112 
113 	dev->mode_config.fb_base = paddr;
114 
115 	fbi->screen_base = msm_gem_get_vaddr(bo);
116 	if (IS_ERR(fbi->screen_base)) {
117 		ret = PTR_ERR(fbi->screen_base);
118 		goto fail_unlock;
119 	}
120 	fbi->screen_size = bo->size;
121 	fbi->fix.smem_start = paddr;
122 	fbi->fix.smem_len = bo->size;
123 
124 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
125 	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
126 
127 	mutex_unlock(&dev->struct_mutex);
128 
129 	return 0;
130 
131 fail_unlock:
132 	mutex_unlock(&dev->struct_mutex);
133 	drm_framebuffer_remove(fb);
134 	return ret;
135 }
136 
137 static const struct drm_fb_helper_funcs msm_fb_helper_funcs = {
138 	.fb_probe = msm_fbdev_create,
139 };
140 
141 /* initialize fbdev helper */
msm_fbdev_init(struct drm_device * dev)142 struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
143 {
144 	struct msm_drm_private *priv = dev->dev_private;
145 	struct msm_fbdev *fbdev = NULL;
146 	struct drm_fb_helper *helper;
147 	int ret;
148 
149 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
150 	if (!fbdev)
151 		goto fail;
152 
153 	helper = &fbdev->base;
154 
155 	drm_fb_helper_prepare(dev, helper, &msm_fb_helper_funcs);
156 
157 	ret = drm_fb_helper_init(dev, helper);
158 	if (ret) {
159 		DRM_DEV_ERROR(dev->dev, "could not init fbdev: ret=%d\n", ret);
160 		goto fail;
161 	}
162 
163 	/* the fw fb could be anywhere in memory */
164 	ret = drm_aperture_remove_framebuffers(false, dev->driver);
165 	if (ret)
166 		goto fini;
167 
168 	ret = drm_fb_helper_initial_config(helper, 32);
169 	if (ret)
170 		goto fini;
171 
172 	priv->fbdev = helper;
173 
174 	return helper;
175 
176 fini:
177 	drm_fb_helper_fini(helper);
178 fail:
179 	kfree(fbdev);
180 	return NULL;
181 }
182 
msm_fbdev_free(struct drm_device * dev)183 void msm_fbdev_free(struct drm_device *dev)
184 {
185 	struct msm_drm_private *priv = dev->dev_private;
186 	struct drm_fb_helper *helper = priv->fbdev;
187 	struct msm_fbdev *fbdev;
188 
189 	DBG();
190 
191 	drm_fb_helper_unregister_fbi(helper);
192 
193 	drm_fb_helper_fini(helper);
194 
195 	fbdev = to_msm_fbdev(priv->fbdev);
196 
197 	/* this will free the backing object */
198 	if (fbdev->fb) {
199 		struct drm_gem_object *bo =
200 			msm_framebuffer_bo(fbdev->fb, 0);
201 		msm_gem_put_vaddr(bo);
202 		drm_framebuffer_remove(fbdev->fb);
203 	}
204 
205 	kfree(fbdev);
206 
207 	priv->fbdev = NULL;
208 }
209