1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* exynos_drm_fbdev.c
3  *
4  * Copyright (c) 2011 Samsung Electronics Co., Ltd.
5  * Authors:
6  *	Inki Dae <inki.dae@samsung.com>
7  *	Joonyoung Shim <jy0922.shim@samsung.com>
8  *	Seung-Woo Kim <sw0312.kim@samsung.com>
9  */
10 
11 #include <linux/console.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/vmalloc.h>
14 
15 #include <drm/drm_crtc.h>
16 #include <drm/drm_fb_helper.h>
17 #include <drm/drm_fourcc.h>
18 #include <drm/drm_probe_helper.h>
19 #include <drm/exynos_drm.h>
20 
21 #include "exynos_drm_drv.h"
22 #include "exynos_drm_fb.h"
23 #include "exynos_drm_fbdev.h"
24 
25 #define MAX_CONNECTOR		4
26 #define PREFERRED_BPP		32
27 
28 #define to_exynos_fbdev(x)	container_of(x, struct exynos_drm_fbdev,\
29 				drm_fb_helper)
30 
31 struct exynos_drm_fbdev {
32 	struct drm_fb_helper	drm_fb_helper;
33 	struct exynos_drm_gem	*exynos_gem;
34 };
35 
36 static int exynos_drm_fb_mmap(struct fb_info *info,
37 			struct vm_area_struct *vma)
38 {
39 	struct drm_fb_helper *helper = info->par;
40 	struct exynos_drm_fbdev *exynos_fbd = to_exynos_fbdev(helper);
41 	struct exynos_drm_gem *exynos_gem = exynos_fbd->exynos_gem;
42 	unsigned long vm_size;
43 	int ret;
44 
45 	vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
46 
47 	vm_size = vma->vm_end - vma->vm_start;
48 
49 	if (vm_size > exynos_gem->size)
50 		return -EINVAL;
51 
52 	ret = dma_mmap_attrs(to_dma_dev(helper->dev), vma, exynos_gem->cookie,
53 			     exynos_gem->dma_addr, exynos_gem->size,
54 			     exynos_gem->dma_attrs);
55 	if (ret < 0) {
56 		DRM_DEV_ERROR(to_dma_dev(helper->dev), "failed to mmap.\n");
57 		return ret;
58 	}
59 
60 	return 0;
61 }
62 
63 static const struct fb_ops exynos_drm_fb_ops = {
64 	.owner		= THIS_MODULE,
65 	DRM_FB_HELPER_DEFAULT_OPS,
66 	.fb_mmap        = exynos_drm_fb_mmap,
67 	.fb_fillrect	= drm_fb_helper_cfb_fillrect,
68 	.fb_copyarea	= drm_fb_helper_cfb_copyarea,
69 	.fb_imageblit	= drm_fb_helper_cfb_imageblit,
70 };
71 
72 static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
73 				   struct drm_fb_helper_surface_size *sizes,
74 				   struct exynos_drm_gem *exynos_gem)
75 {
76 	struct fb_info *fbi;
77 	struct drm_framebuffer *fb = helper->fb;
78 	unsigned int size = fb->width * fb->height * fb->format->cpp[0];
79 	unsigned int nr_pages;
80 	unsigned long offset;
81 
82 	fbi = drm_fb_helper_alloc_fbi(helper);
83 	if (IS_ERR(fbi)) {
84 		DRM_DEV_ERROR(to_dma_dev(helper->dev),
85 			      "failed to allocate fb info.\n");
86 		return PTR_ERR(fbi);
87 	}
88 
89 	fbi->fbops = &exynos_drm_fb_ops;
90 
91 	drm_fb_helper_fill_info(fbi, helper, sizes);
92 
93 	nr_pages = exynos_gem->size >> PAGE_SHIFT;
94 
95 	exynos_gem->kvaddr = (void __iomem *) vmap(exynos_gem->pages, nr_pages,
96 				VM_MAP, pgprot_writecombine(PAGE_KERNEL));
97 	if (!exynos_gem->kvaddr) {
98 		DRM_DEV_ERROR(to_dma_dev(helper->dev),
99 			      "failed to map pages to kernel space.\n");
100 		return -EIO;
101 	}
102 
103 	offset = fbi->var.xoffset * fb->format->cpp[0];
104 	offset += fbi->var.yoffset * fb->pitches[0];
105 
106 	fbi->screen_base = exynos_gem->kvaddr + offset;
107 	fbi->screen_size = size;
108 	fbi->fix.smem_len = size;
109 
110 	return 0;
111 }
112 
113 static int exynos_drm_fbdev_create(struct drm_fb_helper *helper,
114 				    struct drm_fb_helper_surface_size *sizes)
115 {
116 	struct exynos_drm_fbdev *exynos_fbdev = to_exynos_fbdev(helper);
117 	struct exynos_drm_gem *exynos_gem;
118 	struct drm_device *dev = helper->dev;
119 	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
120 	unsigned long size;
121 	int ret;
122 
123 	DRM_DEV_DEBUG_KMS(dev->dev,
124 			  "surface width(%d), height(%d) and bpp(%d\n",
125 			  sizes->surface_width, sizes->surface_height,
126 			  sizes->surface_bpp);
127 
128 	mode_cmd.width = sizes->surface_width;
129 	mode_cmd.height = sizes->surface_height;
130 	mode_cmd.pitches[0] = sizes->surface_width * (sizes->surface_bpp >> 3);
131 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
132 							  sizes->surface_depth);
133 
134 	size = mode_cmd.pitches[0] * mode_cmd.height;
135 
136 	exynos_gem = exynos_drm_gem_create(dev, EXYNOS_BO_CONTIG, size);
137 	/*
138 	 * If physically contiguous memory allocation fails and if IOMMU is
139 	 * supported then try to get buffer from non physically contiguous
140 	 * memory area.
141 	 */
142 	if (IS_ERR(exynos_gem) && is_drm_iommu_supported(dev)) {
143 		dev_warn(dev->dev, "contiguous FB allocation failed, falling back to non-contiguous\n");
144 		exynos_gem = exynos_drm_gem_create(dev, EXYNOS_BO_NONCONTIG,
145 						   size);
146 	}
147 
148 	if (IS_ERR(exynos_gem))
149 		return PTR_ERR(exynos_gem);
150 
151 	exynos_fbdev->exynos_gem = exynos_gem;
152 
153 	helper->fb =
154 		exynos_drm_framebuffer_init(dev, &mode_cmd, &exynos_gem, 1);
155 	if (IS_ERR(helper->fb)) {
156 		DRM_DEV_ERROR(dev->dev, "failed to create drm framebuffer.\n");
157 		ret = PTR_ERR(helper->fb);
158 		goto err_destroy_gem;
159 	}
160 
161 	ret = exynos_drm_fbdev_update(helper, sizes, exynos_gem);
162 	if (ret < 0)
163 		goto err_destroy_framebuffer;
164 
165 	return ret;
166 
167 err_destroy_framebuffer:
168 	drm_framebuffer_cleanup(helper->fb);
169 err_destroy_gem:
170 	exynos_drm_gem_destroy(exynos_gem);
171 
172 	/*
173 	 * if failed, all resources allocated above would be released by
174 	 * drm_mode_config_cleanup() when drm_load() had been called prior
175 	 * to any specific driver such as fimd or hdmi driver.
176 	 */
177 
178 	return ret;
179 }
180 
181 static const struct drm_fb_helper_funcs exynos_drm_fb_helper_funcs = {
182 	.fb_probe =	exynos_drm_fbdev_create,
183 };
184 
185 int exynos_drm_fbdev_init(struct drm_device *dev)
186 {
187 	struct exynos_drm_fbdev *fbdev;
188 	struct exynos_drm_private *private = dev->dev_private;
189 	struct drm_fb_helper *helper;
190 	int ret;
191 
192 	if (!dev->mode_config.num_crtc)
193 		return 0;
194 
195 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
196 	if (!fbdev)
197 		return -ENOMEM;
198 
199 	private->fb_helper = helper = &fbdev->drm_fb_helper;
200 
201 	drm_fb_helper_prepare(dev, helper, &exynos_drm_fb_helper_funcs);
202 
203 	ret = drm_fb_helper_init(dev, helper);
204 	if (ret < 0) {
205 		DRM_DEV_ERROR(dev->dev,
206 			      "failed to initialize drm fb helper.\n");
207 		goto err_init;
208 	}
209 
210 	ret = drm_fb_helper_initial_config(helper, PREFERRED_BPP);
211 	if (ret < 0) {
212 		DRM_DEV_ERROR(dev->dev,
213 			      "failed to set up hw configuration.\n");
214 		goto err_setup;
215 	}
216 
217 	return 0;
218 
219 err_setup:
220 	drm_fb_helper_fini(helper);
221 
222 err_init:
223 	private->fb_helper = NULL;
224 	kfree(fbdev);
225 
226 	return ret;
227 }
228 
229 static void exynos_drm_fbdev_destroy(struct drm_device *dev,
230 				      struct drm_fb_helper *fb_helper)
231 {
232 	struct exynos_drm_fbdev *exynos_fbd = to_exynos_fbdev(fb_helper);
233 	struct exynos_drm_gem *exynos_gem = exynos_fbd->exynos_gem;
234 	struct drm_framebuffer *fb;
235 
236 	vunmap(exynos_gem->kvaddr);
237 
238 	/* release drm framebuffer and real buffer */
239 	if (fb_helper->fb && fb_helper->fb->funcs) {
240 		fb = fb_helper->fb;
241 		if (fb)
242 			drm_framebuffer_remove(fb);
243 	}
244 
245 	drm_fb_helper_unregister_fbi(fb_helper);
246 
247 	drm_fb_helper_fini(fb_helper);
248 }
249 
250 void exynos_drm_fbdev_fini(struct drm_device *dev)
251 {
252 	struct exynos_drm_private *private = dev->dev_private;
253 	struct exynos_drm_fbdev *fbdev;
254 
255 	if (!private || !private->fb_helper)
256 		return;
257 
258 	fbdev = to_exynos_fbdev(private->fb_helper);
259 
260 	exynos_drm_fbdev_destroy(dev, private->fb_helper);
261 	kfree(fbdev);
262 	private->fb_helper = NULL;
263 }
264 
265