xref: /openbmc/linux/drivers/video/fbdev/sbuslib.c (revision b8d312aa)
1 // SPDX-License-Identifier: GPL-2.0
2 /* sbuslib.c: Helper library for SBUS framebuffer drivers.
3  *
4  * Copyright (C) 2003 David S. Miller (davem@redhat.com)
5  */
6 
7 #include <linux/compat.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/string.h>
11 #include <linux/fb.h>
12 #include <linux/mm.h>
13 #include <linux/uaccess.h>
14 #include <linux/of_device.h>
15 
16 #include <asm/fbio.h>
17 
18 #include "sbuslib.h"
19 
20 void sbusfb_fill_var(struct fb_var_screeninfo *var, struct device_node *dp,
21 		     int bpp)
22 {
23 	memset(var, 0, sizeof(*var));
24 
25 	var->xres = of_getintprop_default(dp, "width", 1152);
26 	var->yres = of_getintprop_default(dp, "height", 900);
27 	var->xres_virtual = var->xres;
28 	var->yres_virtual = var->yres;
29 	var->bits_per_pixel = bpp;
30 }
31 
32 EXPORT_SYMBOL(sbusfb_fill_var);
33 
34 static unsigned long sbusfb_mmapsize(long size, unsigned long fbsize)
35 {
36 	if (size == SBUS_MMAP_EMPTY) return 0;
37 	if (size >= 0) return size;
38 	return fbsize * (-size);
39 }
40 
41 int sbusfb_mmap_helper(struct sbus_mmap_map *map,
42 		       unsigned long physbase,
43 		       unsigned long fbsize,
44 		       unsigned long iospace,
45 		       struct vm_area_struct *vma)
46 {
47 	unsigned int size, page, r, map_size;
48 	unsigned long map_offset = 0;
49 	unsigned long off;
50 	int i;
51 
52 	if (!(vma->vm_flags & (VM_SHARED | VM_MAYSHARE)))
53 		return -EINVAL;
54 
55 	size = vma->vm_end - vma->vm_start;
56 	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT))
57 		return -EINVAL;
58 
59 	off = vma->vm_pgoff << PAGE_SHIFT;
60 
61 	/* VM_IO | VM_DONTEXPAND | VM_DONTDUMP are set by remap_pfn_range() */
62 
63 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
64 
65 	/* Each page, see which map applies */
66 	for (page = 0; page < size; ){
67 		map_size = 0;
68 		for (i = 0; map[i].size; i++)
69 			if (map[i].voff == off+page) {
70 				map_size = sbusfb_mmapsize(map[i].size, fbsize);
71 #ifdef __sparc_v9__
72 #define POFF_MASK	(PAGE_MASK|0x1UL)
73 #else
74 #define POFF_MASK	(PAGE_MASK)
75 #endif
76 				map_offset = (physbase + map[i].poff) & POFF_MASK;
77 				break;
78 			}
79 		if (!map_size) {
80 			page += PAGE_SIZE;
81 			continue;
82 		}
83 		if (page + map_size > size)
84 			map_size = size - page;
85 		r = io_remap_pfn_range(vma,
86 					vma->vm_start + page,
87 					MK_IOSPACE_PFN(iospace,
88 						map_offset >> PAGE_SHIFT),
89 					map_size,
90 					vma->vm_page_prot);
91 		if (r)
92 			return -EAGAIN;
93 		page += map_size;
94 	}
95 
96 	return 0;
97 }
98 EXPORT_SYMBOL(sbusfb_mmap_helper);
99 
100 int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg,
101 			struct fb_info *info,
102 			int type, int fb_depth, unsigned long fb_size)
103 {
104 	switch(cmd) {
105 	case FBIOGTYPE: {
106 		struct fbtype __user *f = (struct fbtype __user *) arg;
107 
108 		if (put_user(type, &f->fb_type) ||
109 		    put_user(info->var.yres, &f->fb_height) ||
110 		    put_user(info->var.xres, &f->fb_width) ||
111 		    put_user(fb_depth, &f->fb_depth) ||
112 		    put_user(0, &f->fb_cmsize) ||
113 		    put_user(fb_size, &f->fb_cmsize))
114 			return -EFAULT;
115 		return 0;
116 	}
117 	case FBIOPUTCMAP_SPARC: {
118 		struct fbcmap __user *c = (struct fbcmap __user *) arg;
119 		struct fb_cmap cmap;
120 		u16 red, green, blue;
121 		u8 red8, green8, blue8;
122 		unsigned char __user *ured;
123 		unsigned char __user *ugreen;
124 		unsigned char __user *ublue;
125 		unsigned int index, count, i;
126 
127 		if (get_user(index, &c->index) ||
128 		    get_user(count, &c->count) ||
129 		    get_user(ured, &c->red) ||
130 		    get_user(ugreen, &c->green) ||
131 		    get_user(ublue, &c->blue))
132 			return -EFAULT;
133 
134 		cmap.len = 1;
135 		cmap.red = &red;
136 		cmap.green = &green;
137 		cmap.blue = &blue;
138 		cmap.transp = NULL;
139 		for (i = 0; i < count; i++) {
140 			int err;
141 
142 			if (get_user(red8, &ured[i]) ||
143 			    get_user(green8, &ugreen[i]) ||
144 			    get_user(blue8, &ublue[i]))
145 				return -EFAULT;
146 
147 			red = red8 << 8;
148 			green = green8 << 8;
149 			blue = blue8 << 8;
150 
151 			cmap.start = index + i;
152 			err = fb_set_cmap(&cmap, info);
153 			if (err)
154 				return err;
155 		}
156 		return 0;
157 	}
158 	case FBIOGETCMAP_SPARC: {
159 		struct fbcmap __user *c = (struct fbcmap __user *) arg;
160 		unsigned char __user *ured;
161 		unsigned char __user *ugreen;
162 		unsigned char __user *ublue;
163 		struct fb_cmap *cmap = &info->cmap;
164 		unsigned int index, count, i;
165 		u8 red, green, blue;
166 
167 		if (get_user(index, &c->index) ||
168 		    get_user(count, &c->count) ||
169 		    get_user(ured, &c->red) ||
170 		    get_user(ugreen, &c->green) ||
171 		    get_user(ublue, &c->blue))
172 			return -EFAULT;
173 
174 		if (index > cmap->len || count > cmap->len - index)
175 			return -EINVAL;
176 
177 		for (i = 0; i < count; i++) {
178 			red = cmap->red[index + i] >> 8;
179 			green = cmap->green[index + i] >> 8;
180 			blue = cmap->blue[index + i] >> 8;
181 			if (put_user(red, &ured[i]) ||
182 			    put_user(green, &ugreen[i]) ||
183 			    put_user(blue, &ublue[i]))
184 				return -EFAULT;
185 		}
186 		return 0;
187 	}
188 	default:
189 		return -EINVAL;
190 	}
191 }
192 EXPORT_SYMBOL(sbusfb_ioctl_helper);
193 
194 #ifdef CONFIG_COMPAT
195 static int fbiogetputcmap(struct fb_info *info, unsigned int cmd, unsigned long arg)
196 {
197 	struct fbcmap32 __user *argp = (void __user *)arg;
198 	struct fbcmap __user *p = compat_alloc_user_space(sizeof(*p));
199 	u32 addr;
200 	int ret;
201 
202 	ret = copy_in_user(p, argp, 2 * sizeof(int));
203 	ret |= get_user(addr, &argp->red);
204 	ret |= put_user(compat_ptr(addr), &p->red);
205 	ret |= get_user(addr, &argp->green);
206 	ret |= put_user(compat_ptr(addr), &p->green);
207 	ret |= get_user(addr, &argp->blue);
208 	ret |= put_user(compat_ptr(addr), &p->blue);
209 	if (ret)
210 		return -EFAULT;
211 	return info->fbops->fb_ioctl(info,
212 			(cmd == FBIOPUTCMAP32) ?
213 			FBIOPUTCMAP_SPARC : FBIOGETCMAP_SPARC,
214 			(unsigned long)p);
215 }
216 
217 static int fbiogscursor(struct fb_info *info, unsigned long arg)
218 {
219 	struct fbcursor __user *p = compat_alloc_user_space(sizeof(*p));
220 	struct fbcursor32 __user *argp =  (void __user *)arg;
221 	compat_uptr_t addr;
222 	int ret;
223 
224 	ret = copy_in_user(p, argp,
225 			      2 * sizeof (short) + 2 * sizeof(struct fbcurpos));
226 	ret |= copy_in_user(&p->size, &argp->size, sizeof(struct fbcurpos));
227 	ret |= copy_in_user(&p->cmap, &argp->cmap, 2 * sizeof(int));
228 	ret |= get_user(addr, &argp->cmap.red);
229 	ret |= put_user(compat_ptr(addr), &p->cmap.red);
230 	ret |= get_user(addr, &argp->cmap.green);
231 	ret |= put_user(compat_ptr(addr), &p->cmap.green);
232 	ret |= get_user(addr, &argp->cmap.blue);
233 	ret |= put_user(compat_ptr(addr), &p->cmap.blue);
234 	ret |= get_user(addr, &argp->mask);
235 	ret |= put_user(compat_ptr(addr), &p->mask);
236 	ret |= get_user(addr, &argp->image);
237 	ret |= put_user(compat_ptr(addr), &p->image);
238 	if (ret)
239 		return -EFAULT;
240 	return info->fbops->fb_ioctl(info, FBIOSCURSOR, (unsigned long)p);
241 }
242 
243 int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
244 {
245 	switch (cmd) {
246 	case FBIOGTYPE:
247 	case FBIOSATTR:
248 	case FBIOGATTR:
249 	case FBIOSVIDEO:
250 	case FBIOGVIDEO:
251 	case FBIOGCURSOR32:	/* This is not implemented yet.
252 				   Later it should be converted... */
253 	case FBIOSCURPOS:
254 	case FBIOGCURPOS:
255 	case FBIOGCURMAX:
256 		return info->fbops->fb_ioctl(info, cmd, arg);
257 	case FBIOPUTCMAP32:
258 		return fbiogetputcmap(info, cmd, arg);
259 	case FBIOGETCMAP32:
260 		return fbiogetputcmap(info, cmd, arg);
261 	case FBIOSCURSOR32:
262 		return fbiogscursor(info, arg);
263 	default:
264 		return -ENOIOCTLCMD;
265 	}
266 }
267 EXPORT_SYMBOL(sbusfb_compat_ioctl);
268 #endif
269