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/kernel.h>
9 #include <linux/module.h>
10 
11 #include <drm/drm_fb_helper.h>
12 #include <drm/drm_fourcc.h>
13 
14 #include "armada_crtc.h"
15 #include "armada_drm.h"
16 #include "armada_fb.h"
17 #include "armada_gem.h"
18 
19 static const struct fb_ops armada_fb_ops = {
20 	.owner		= THIS_MODULE,
21 	DRM_FB_HELPER_DEFAULT_OPS,
22 	.fb_read	= drm_fb_helper_cfb_read,
23 	.fb_write	= drm_fb_helper_cfb_write,
24 	.fb_fillrect	= drm_fb_helper_cfb_fillrect,
25 	.fb_copyarea	= drm_fb_helper_cfb_copyarea,
26 	.fb_imageblit	= drm_fb_helper_cfb_imageblit,
27 };
28 
29 static int armada_fbdev_create(struct drm_fb_helper *fbh,
30 	struct drm_fb_helper_surface_size *sizes)
31 {
32 	struct drm_device *dev = fbh->dev;
33 	struct drm_mode_fb_cmd2 mode;
34 	struct armada_framebuffer *dfb;
35 	struct armada_gem_object *obj;
36 	struct fb_info *info;
37 	int size, ret;
38 	void *ptr;
39 
40 	memset(&mode, 0, sizeof(mode));
41 	mode.width = sizes->surface_width;
42 	mode.height = sizes->surface_height;
43 	mode.pitches[0] = armada_pitch(mode.width, sizes->surface_bpp);
44 	mode.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
45 					sizes->surface_depth);
46 
47 	size = mode.pitches[0] * mode.height;
48 	obj = armada_gem_alloc_private_object(dev, size);
49 	if (!obj) {
50 		DRM_ERROR("failed to allocate fb memory\n");
51 		return -ENOMEM;
52 	}
53 
54 	ret = armada_gem_linear_back(dev, obj);
55 	if (ret) {
56 		drm_gem_object_put(&obj->obj);
57 		return ret;
58 	}
59 
60 	ptr = armada_gem_map_object(dev, obj);
61 	if (!ptr) {
62 		drm_gem_object_put(&obj->obj);
63 		return -ENOMEM;
64 	}
65 
66 	dfb = armada_framebuffer_create(dev, &mode, obj);
67 
68 	/*
69 	 * A reference is now held by the framebuffer object if
70 	 * successful, otherwise this drops the ref for the error path.
71 	 */
72 	drm_gem_object_put(&obj->obj);
73 
74 	if (IS_ERR(dfb))
75 		return PTR_ERR(dfb);
76 
77 	info = drm_fb_helper_alloc_info(fbh);
78 	if (IS_ERR(info)) {
79 		ret = PTR_ERR(info);
80 		goto err_fballoc;
81 	}
82 
83 	info->fbops = &armada_fb_ops;
84 	info->fix.smem_start = obj->phys_addr;
85 	info->fix.smem_len = obj->obj.size;
86 	info->screen_size = obj->obj.size;
87 	info->screen_base = ptr;
88 	fbh->fb = &dfb->fb;
89 
90 	drm_fb_helper_fill_info(info, fbh, sizes);
91 
92 	DRM_DEBUG_KMS("allocated %dx%d %dbpp fb: 0x%08llx\n",
93 		dfb->fb.width, dfb->fb.height, dfb->fb.format->cpp[0] * 8,
94 		(unsigned long long)obj->phys_addr);
95 
96 	return 0;
97 
98  err_fballoc:
99 	dfb->fb.funcs->destroy(&dfb->fb);
100 	return ret;
101 }
102 
103 static int armada_fb_probe(struct drm_fb_helper *fbh,
104 	struct drm_fb_helper_surface_size *sizes)
105 {
106 	int ret = 0;
107 
108 	if (!fbh->fb) {
109 		ret = armada_fbdev_create(fbh, sizes);
110 		if (ret == 0)
111 			ret = 1;
112 	}
113 	return ret;
114 }
115 
116 static const struct drm_fb_helper_funcs armada_fb_helper_funcs = {
117 	.fb_probe	= armada_fb_probe,
118 };
119 
120 int armada_fbdev_init(struct drm_device *dev)
121 {
122 	struct armada_private *priv = drm_to_armada_dev(dev);
123 	struct drm_fb_helper *fbh;
124 	int ret;
125 
126 	fbh = devm_kzalloc(dev->dev, sizeof(*fbh), GFP_KERNEL);
127 	if (!fbh)
128 		return -ENOMEM;
129 
130 	priv->fbdev = fbh;
131 
132 	drm_fb_helper_prepare(dev, fbh, &armada_fb_helper_funcs);
133 
134 	ret = drm_fb_helper_init(dev, fbh);
135 	if (ret) {
136 		DRM_ERROR("failed to initialize drm fb helper\n");
137 		goto err_fb_helper;
138 	}
139 
140 	ret = drm_fb_helper_initial_config(fbh, 32);
141 	if (ret) {
142 		DRM_ERROR("failed to set initial config\n");
143 		goto err_fb_setup;
144 	}
145 
146 	return 0;
147  err_fb_setup:
148 	drm_fb_helper_fini(fbh);
149  err_fb_helper:
150 	priv->fbdev = NULL;
151 	return ret;
152 }
153 
154 void armada_fbdev_fini(struct drm_device *dev)
155 {
156 	struct armada_private *priv = drm_to_armada_dev(dev);
157 	struct drm_fb_helper *fbh = priv->fbdev;
158 
159 	if (fbh) {
160 		drm_fb_helper_unregister_info(fbh);
161 
162 		drm_fb_helper_fini(fbh);
163 
164 		if (fbh->fb)
165 			fbh->fb->funcs->destroy(fbh->fb);
166 
167 		priv->fbdev = NULL;
168 	}
169 }
170