1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012 Russell King
4  *  Written from the i915 driver.
5  */
6 
7 #include <linux/errno.h>
8 #include <linux/fb.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 
12 #include <drm/drm_crtc_helper.h>
13 #include <drm/drm_drv.h>
14 #include <drm/drm_fb_helper.h>
15 #include <drm/drm_fourcc.h>
16 
17 #include "armada_crtc.h"
18 #include "armada_drm.h"
19 #include "armada_fb.h"
20 #include "armada_gem.h"
21 
22 static void armada_fbdev_fb_destroy(struct fb_info *info)
23 {
24 	struct drm_fb_helper *fbh = info->par;
25 
26 	drm_fb_helper_fini(fbh);
27 
28 	fbh->fb->funcs->destroy(fbh->fb);
29 
30 	drm_client_release(&fbh->client);
31 	drm_fb_helper_unprepare(fbh);
32 	kfree(fbh);
33 }
34 
35 static const struct fb_ops armada_fb_ops = {
36 	.owner		= THIS_MODULE,
37 	FB_DEFAULT_IOMEM_OPS,
38 	DRM_FB_HELPER_DEFAULT_OPS,
39 	.fb_destroy	= armada_fbdev_fb_destroy,
40 };
41 
42 static int armada_fbdev_create(struct drm_fb_helper *fbh,
43 	struct drm_fb_helper_surface_size *sizes)
44 {
45 	struct drm_device *dev = fbh->dev;
46 	struct drm_mode_fb_cmd2 mode;
47 	struct armada_framebuffer *dfb;
48 	struct armada_gem_object *obj;
49 	struct fb_info *info;
50 	int size, ret;
51 	void *ptr;
52 
53 	memset(&mode, 0, sizeof(mode));
54 	mode.width = sizes->surface_width;
55 	mode.height = sizes->surface_height;
56 	mode.pitches[0] = armada_pitch(mode.width, sizes->surface_bpp);
57 	mode.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
58 					sizes->surface_depth);
59 
60 	size = mode.pitches[0] * mode.height;
61 	obj = armada_gem_alloc_private_object(dev, size);
62 	if (!obj) {
63 		DRM_ERROR("failed to allocate fb memory\n");
64 		return -ENOMEM;
65 	}
66 
67 	ret = armada_gem_linear_back(dev, obj);
68 	if (ret) {
69 		drm_gem_object_put(&obj->obj);
70 		return ret;
71 	}
72 
73 	ptr = armada_gem_map_object(dev, obj);
74 	if (!ptr) {
75 		drm_gem_object_put(&obj->obj);
76 		return -ENOMEM;
77 	}
78 
79 	dfb = armada_framebuffer_create(dev, &mode, obj);
80 
81 	/*
82 	 * A reference is now held by the framebuffer object if
83 	 * successful, otherwise this drops the ref for the error path.
84 	 */
85 	drm_gem_object_put(&obj->obj);
86 
87 	if (IS_ERR(dfb))
88 		return PTR_ERR(dfb);
89 
90 	info = drm_fb_helper_alloc_info(fbh);
91 	if (IS_ERR(info)) {
92 		ret = PTR_ERR(info);
93 		goto err_fballoc;
94 	}
95 
96 	info->fbops = &armada_fb_ops;
97 	info->fix.smem_start = obj->phys_addr;
98 	info->fix.smem_len = obj->obj.size;
99 	info->screen_size = obj->obj.size;
100 	info->screen_base = ptr;
101 	fbh->fb = &dfb->fb;
102 
103 	drm_fb_helper_fill_info(info, fbh, sizes);
104 
105 	DRM_DEBUG_KMS("allocated %dx%d %dbpp fb: 0x%08llx\n",
106 		dfb->fb.width, dfb->fb.height, dfb->fb.format->cpp[0] * 8,
107 		(unsigned long long)obj->phys_addr);
108 
109 	return 0;
110 
111  err_fballoc:
112 	dfb->fb.funcs->destroy(&dfb->fb);
113 	return ret;
114 }
115 
116 static int armada_fb_probe(struct drm_fb_helper *fbh,
117 	struct drm_fb_helper_surface_size *sizes)
118 {
119 	int ret = 0;
120 
121 	if (!fbh->fb) {
122 		ret = armada_fbdev_create(fbh, sizes);
123 		if (ret == 0)
124 			ret = 1;
125 	}
126 	return ret;
127 }
128 
129 static const struct drm_fb_helper_funcs armada_fb_helper_funcs = {
130 	.fb_probe	= armada_fb_probe,
131 };
132 
133 /*
134  * Fbdev client and struct drm_client_funcs
135  */
136 
137 static void armada_fbdev_client_unregister(struct drm_client_dev *client)
138 {
139 	struct drm_fb_helper *fbh = drm_fb_helper_from_client(client);
140 
141 	if (fbh->info) {
142 		drm_fb_helper_unregister_info(fbh);
143 	} else {
144 		drm_client_release(&fbh->client);
145 		drm_fb_helper_unprepare(fbh);
146 		kfree(fbh);
147 	}
148 }
149 
150 static int armada_fbdev_client_restore(struct drm_client_dev *client)
151 {
152 	drm_fb_helper_lastclose(client->dev);
153 
154 	return 0;
155 }
156 
157 static int armada_fbdev_client_hotplug(struct drm_client_dev *client)
158 {
159 	struct drm_fb_helper *fbh = drm_fb_helper_from_client(client);
160 	struct drm_device *dev = client->dev;
161 	int ret;
162 
163 	if (dev->fb_helper)
164 		return drm_fb_helper_hotplug_event(dev->fb_helper);
165 
166 	ret = drm_fb_helper_init(dev, fbh);
167 	if (ret)
168 		goto err_drm_err;
169 
170 	if (!drm_drv_uses_atomic_modeset(dev))
171 		drm_helper_disable_unused_functions(dev);
172 
173 	ret = drm_fb_helper_initial_config(fbh);
174 	if (ret)
175 		goto err_drm_fb_helper_fini;
176 
177 	return 0;
178 
179 err_drm_fb_helper_fini:
180 	drm_fb_helper_fini(fbh);
181 err_drm_err:
182 	drm_err(dev, "armada: Failed to setup fbdev emulation (ret=%d)\n", ret);
183 	return ret;
184 }
185 
186 static const struct drm_client_funcs armada_fbdev_client_funcs = {
187 	.owner		= THIS_MODULE,
188 	.unregister	= armada_fbdev_client_unregister,
189 	.restore	= armada_fbdev_client_restore,
190 	.hotplug	= armada_fbdev_client_hotplug,
191 };
192 
193 void armada_fbdev_setup(struct drm_device *dev)
194 {
195 	struct drm_fb_helper *fbh;
196 	int ret;
197 
198 	drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
199 	drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
200 
201 	fbh = kzalloc(sizeof(*fbh), GFP_KERNEL);
202 	if (!fbh)
203 		return;
204 	drm_fb_helper_prepare(dev, fbh, 32, &armada_fb_helper_funcs);
205 
206 	ret = drm_client_init(dev, &fbh->client, "fbdev", &armada_fbdev_client_funcs);
207 	if (ret) {
208 		drm_err(dev, "Failed to register client: %d\n", ret);
209 		goto err_drm_client_init;
210 	}
211 
212 	drm_client_register(&fbh->client);
213 
214 	return;
215 
216 err_drm_client_init:
217 	drm_fb_helper_unprepare(fbh);
218 	kfree(fbh);
219 	return;
220 }
221