1 // SPDX-License-Identifier: GPL-2.0 or MIT
2 /*
3 * Copyright (C) 2016 Noralf Trønnes
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 */
10
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/io.h>
14
15 #include <drm/drm_format_helper.h>
16 #include <drm/drm_framebuffer.h>
17 #include <drm/drm_fourcc.h>
18 #include <drm/drm_rect.h>
19
clip_offset(struct drm_rect * clip,unsigned int pitch,unsigned int cpp)20 static unsigned int clip_offset(struct drm_rect *clip,
21 unsigned int pitch, unsigned int cpp)
22 {
23 return clip->y1 * pitch + clip->x1 * cpp;
24 }
25
26 /**
27 * drm_fb_memcpy - Copy clip buffer
28 * @dst: Destination buffer
29 * @vaddr: Source buffer
30 * @fb: DRM framebuffer
31 * @clip: Clip rectangle area to copy
32 *
33 * This function does not apply clipping on dst, i.e. the destination
34 * is a small buffer containing the clip rect only.
35 */
drm_fb_memcpy(void * dst,void * vaddr,struct drm_framebuffer * fb,struct drm_rect * clip)36 void drm_fb_memcpy(void *dst, void *vaddr, struct drm_framebuffer *fb,
37 struct drm_rect *clip)
38 {
39 unsigned int cpp = fb->format->cpp[0];
40 size_t len = (clip->x2 - clip->x1) * cpp;
41 unsigned int y, lines = clip->y2 - clip->y1;
42
43 vaddr += clip_offset(clip, fb->pitches[0], cpp);
44 for (y = 0; y < lines; y++) {
45 memcpy(dst, vaddr, len);
46 vaddr += fb->pitches[0];
47 dst += len;
48 }
49 }
50 EXPORT_SYMBOL(drm_fb_memcpy);
51
52 /**
53 * drm_fb_memcpy_dstclip - Copy clip buffer
54 * @dst: Destination buffer (iomem)
55 * @vaddr: Source buffer
56 * @fb: DRM framebuffer
57 * @clip: Clip rectangle area to copy
58 *
59 * This function applies clipping on dst, i.e. the destination is a
60 * full (iomem) framebuffer but only the clip rect content is copied over.
61 */
drm_fb_memcpy_dstclip(void __iomem * dst,void * vaddr,struct drm_framebuffer * fb,struct drm_rect * clip)62 void drm_fb_memcpy_dstclip(void __iomem *dst, void *vaddr,
63 struct drm_framebuffer *fb,
64 struct drm_rect *clip)
65 {
66 unsigned int cpp = fb->format->cpp[0];
67 unsigned int offset = clip_offset(clip, fb->pitches[0], cpp);
68 size_t len = (clip->x2 - clip->x1) * cpp;
69 unsigned int y, lines = clip->y2 - clip->y1;
70
71 vaddr += offset;
72 dst += offset;
73 for (y = 0; y < lines; y++) {
74 memcpy_toio(dst, vaddr, len);
75 vaddr += fb->pitches[0];
76 dst += fb->pitches[0];
77 }
78 }
79 EXPORT_SYMBOL(drm_fb_memcpy_dstclip);
80
81 /**
82 * drm_fb_swab - Swap bytes into clip buffer
83 * @dst: Destination buffer
84 * @src: Source buffer
85 * @fb: DRM framebuffer
86 * @clip: Clip rectangle area to copy
87 * @cached: Source buffer is mapped cached (eg. not write-combined)
88 *
89 * If @cached is false a temporary buffer is used to cache one pixel line at a
90 * time to speed up slow uncached reads.
91 *
92 * This function does not apply clipping on dst, i.e. the destination
93 * is a small buffer containing the clip rect only.
94 */
drm_fb_swab(void * dst,void * src,struct drm_framebuffer * fb,struct drm_rect * clip,bool cached)95 void drm_fb_swab(void *dst, void *src, struct drm_framebuffer *fb,
96 struct drm_rect *clip, bool cached)
97 {
98 u8 cpp = fb->format->cpp[0];
99 size_t len = drm_rect_width(clip) * cpp;
100 u16 *src16, *dst16 = dst;
101 u32 *src32, *dst32 = dst;
102 unsigned int x, y;
103 void *buf = NULL;
104
105 if (WARN_ON_ONCE(cpp != 2 && cpp != 4))
106 return;
107
108 if (!cached)
109 buf = kmalloc(len, GFP_KERNEL);
110
111 src += clip_offset(clip, fb->pitches[0], cpp);
112
113 for (y = clip->y1; y < clip->y2; y++) {
114 if (buf) {
115 memcpy(buf, src, len);
116 src16 = buf;
117 src32 = buf;
118 } else {
119 src16 = src;
120 src32 = src;
121 }
122
123 for (x = clip->x1; x < clip->x2; x++) {
124 if (cpp == 4)
125 *dst32++ = swab32(*src32++);
126 else
127 *dst16++ = swab16(*src16++);
128 }
129
130 src += fb->pitches[0];
131 }
132
133 kfree(buf);
134 }
135 EXPORT_SYMBOL(drm_fb_swab);
136
drm_fb_xrgb8888_to_rgb565_line(u16 * dbuf,u32 * sbuf,unsigned int pixels,bool swab)137 static void drm_fb_xrgb8888_to_rgb565_line(u16 *dbuf, u32 *sbuf,
138 unsigned int pixels,
139 bool swab)
140 {
141 unsigned int x;
142 u16 val16;
143
144 for (x = 0; x < pixels; x++) {
145 val16 = ((sbuf[x] & 0x00F80000) >> 8) |
146 ((sbuf[x] & 0x0000FC00) >> 5) |
147 ((sbuf[x] & 0x000000F8) >> 3);
148 if (swab)
149 dbuf[x] = swab16(val16);
150 else
151 dbuf[x] = val16;
152 }
153 }
154
155 /**
156 * drm_fb_xrgb8888_to_rgb565 - Convert XRGB8888 to RGB565 clip buffer
157 * @dst: RGB565 destination buffer
158 * @vaddr: XRGB8888 source buffer
159 * @fb: DRM framebuffer
160 * @clip: Clip rectangle area to copy
161 * @swab: Swap bytes
162 *
163 * Drivers can use this function for RGB565 devices that don't natively
164 * support XRGB8888.
165 *
166 * This function does not apply clipping on dst, i.e. the destination
167 * is a small buffer containing the clip rect only.
168 */
drm_fb_xrgb8888_to_rgb565(void * dst,void * vaddr,struct drm_framebuffer * fb,struct drm_rect * clip,bool swab)169 void drm_fb_xrgb8888_to_rgb565(void *dst, void *vaddr,
170 struct drm_framebuffer *fb,
171 struct drm_rect *clip, bool swab)
172 {
173 size_t linepixels = clip->x2 - clip->x1;
174 size_t src_len = linepixels * sizeof(u32);
175 size_t dst_len = linepixels * sizeof(u16);
176 unsigned y, lines = clip->y2 - clip->y1;
177 void *sbuf;
178
179 /*
180 * The cma memory is write-combined so reads are uncached.
181 * Speed up by fetching one line at a time.
182 */
183 sbuf = kmalloc(src_len, GFP_KERNEL);
184 if (!sbuf)
185 return;
186
187 vaddr += clip_offset(clip, fb->pitches[0], sizeof(u32));
188 for (y = 0; y < lines; y++) {
189 memcpy(sbuf, vaddr, src_len);
190 drm_fb_xrgb8888_to_rgb565_line(dst, sbuf, linepixels, swab);
191 vaddr += fb->pitches[0];
192 dst += dst_len;
193 }
194
195 kfree(sbuf);
196 }
197 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565);
198
199 /**
200 * drm_fb_xrgb8888_to_rgb565_dstclip - Convert XRGB8888 to RGB565 clip buffer
201 * @dst: RGB565 destination buffer (iomem)
202 * @dst_pitch: destination buffer pitch
203 * @vaddr: XRGB8888 source buffer
204 * @fb: DRM framebuffer
205 * @clip: Clip rectangle area to copy
206 * @swab: Swap bytes
207 *
208 * Drivers can use this function for RGB565 devices that don't natively
209 * support XRGB8888.
210 *
211 * This function applies clipping on dst, i.e. the destination is a
212 * full (iomem) framebuffer but only the clip rect content is copied over.
213 */
drm_fb_xrgb8888_to_rgb565_dstclip(void __iomem * dst,unsigned int dst_pitch,void * vaddr,struct drm_framebuffer * fb,struct drm_rect * clip,bool swab)214 void drm_fb_xrgb8888_to_rgb565_dstclip(void __iomem *dst, unsigned int dst_pitch,
215 void *vaddr, struct drm_framebuffer *fb,
216 struct drm_rect *clip, bool swab)
217 {
218 size_t linepixels = clip->x2 - clip->x1;
219 size_t dst_len = linepixels * sizeof(u16);
220 unsigned y, lines = clip->y2 - clip->y1;
221 void *dbuf;
222
223 dbuf = kmalloc(dst_len, GFP_KERNEL);
224 if (!dbuf)
225 return;
226
227 vaddr += clip_offset(clip, fb->pitches[0], sizeof(u32));
228 dst += clip_offset(clip, dst_pitch, sizeof(u16));
229 for (y = 0; y < lines; y++) {
230 drm_fb_xrgb8888_to_rgb565_line(dbuf, vaddr, linepixels, swab);
231 memcpy_toio(dst, dbuf, dst_len);
232 vaddr += fb->pitches[0];
233 dst += dst_len;
234 }
235
236 kfree(dbuf);
237 }
238 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb565_dstclip);
239
drm_fb_xrgb8888_to_rgb888_line(u8 * dbuf,u32 * sbuf,unsigned int pixels)240 static void drm_fb_xrgb8888_to_rgb888_line(u8 *dbuf, u32 *sbuf,
241 unsigned int pixels)
242 {
243 unsigned int x;
244
245 for (x = 0; x < pixels; x++) {
246 *dbuf++ = (sbuf[x] & 0x000000FF) >> 0;
247 *dbuf++ = (sbuf[x] & 0x0000FF00) >> 8;
248 *dbuf++ = (sbuf[x] & 0x00FF0000) >> 16;
249 }
250 }
251
252 /**
253 * drm_fb_xrgb8888_to_rgb888_dstclip - Convert XRGB8888 to RGB888 clip buffer
254 * @dst: RGB565 destination buffer (iomem)
255 * @dst_pitch: destination buffer pitch
256 * @vaddr: XRGB8888 source buffer
257 * @fb: DRM framebuffer
258 * @clip: Clip rectangle area to copy
259 *
260 * Drivers can use this function for RGB888 devices that don't natively
261 * support XRGB8888.
262 *
263 * This function applies clipping on dst, i.e. the destination is a
264 * full (iomem) framebuffer but only the clip rect content is copied over.
265 */
drm_fb_xrgb8888_to_rgb888_dstclip(void __iomem * dst,unsigned int dst_pitch,void * vaddr,struct drm_framebuffer * fb,struct drm_rect * clip)266 void drm_fb_xrgb8888_to_rgb888_dstclip(void __iomem *dst, unsigned int dst_pitch,
267 void *vaddr, struct drm_framebuffer *fb,
268 struct drm_rect *clip)
269 {
270 size_t linepixels = clip->x2 - clip->x1;
271 size_t dst_len = linepixels * 3;
272 unsigned y, lines = clip->y2 - clip->y1;
273 void *dbuf;
274
275 dbuf = kmalloc(dst_len, GFP_KERNEL);
276 if (!dbuf)
277 return;
278
279 vaddr += clip_offset(clip, fb->pitches[0], sizeof(u32));
280 dst += clip_offset(clip, dst_pitch, sizeof(u16));
281 for (y = 0; y < lines; y++) {
282 drm_fb_xrgb8888_to_rgb888_line(dbuf, vaddr, linepixels);
283 memcpy_toio(dst, dbuf, dst_len);
284 vaddr += fb->pitches[0];
285 dst += dst_len;
286 }
287
288 kfree(dbuf);
289 }
290 EXPORT_SYMBOL(drm_fb_xrgb8888_to_rgb888_dstclip);
291
292 /**
293 * drm_fb_xrgb8888_to_gray8 - Convert XRGB8888 to grayscale
294 * @dst: 8-bit grayscale destination buffer
295 * @vaddr: XRGB8888 source buffer
296 * @fb: DRM framebuffer
297 * @clip: Clip rectangle area to copy
298 *
299 * Drm doesn't have native monochrome or grayscale support.
300 * Such drivers can announce the commonly supported XR24 format to userspace
301 * and use this function to convert to the native format.
302 *
303 * Monochrome drivers will use the most significant bit,
304 * where 1 means foreground color and 0 background color.
305 *
306 * ITU BT.601 is used for the RGB -> luma (brightness) conversion.
307 */
drm_fb_xrgb8888_to_gray8(u8 * dst,void * vaddr,struct drm_framebuffer * fb,struct drm_rect * clip)308 void drm_fb_xrgb8888_to_gray8(u8 *dst, void *vaddr, struct drm_framebuffer *fb,
309 struct drm_rect *clip)
310 {
311 unsigned int len = (clip->x2 - clip->x1) * sizeof(u32);
312 unsigned int x, y;
313 void *buf;
314 u32 *src;
315
316 if (WARN_ON(fb->format->format != DRM_FORMAT_XRGB8888))
317 return;
318 /*
319 * The cma memory is write-combined so reads are uncached.
320 * Speed up by fetching one line at a time.
321 */
322 buf = kmalloc(len, GFP_KERNEL);
323 if (!buf)
324 return;
325
326 for (y = clip->y1; y < clip->y2; y++) {
327 src = vaddr + (y * fb->pitches[0]);
328 src += clip->x1;
329 memcpy(buf, src, len);
330 src = buf;
331 for (x = clip->x1; x < clip->x2; x++) {
332 u8 r = (*src & 0x00ff0000) >> 16;
333 u8 g = (*src & 0x0000ff00) >> 8;
334 u8 b = *src & 0x000000ff;
335
336 /* ITU BT.601: Y = 0.299 R + 0.587 G + 0.114 B */
337 *dst++ = (3 * r + 6 * g + b) / 10;
338 src++;
339 }
340 }
341
342 kfree(buf);
343 }
344 EXPORT_SYMBOL(drm_fb_xrgb8888_to_gray8);
345
346
