1/*
2 *  Generic BitBLT function for frame buffer with packed pixels of any depth.
3 *
4 *      Copyright (C)  June 1999 James Simmons
5 *
6 *  This file is subject to the terms and conditions of the GNU General Public
7 *  License.  See the file COPYING in the main directory of this archive for
8 *  more details.
9 *
10 * NOTES:
11 *
12 *    This function copys a image from system memory to video memory. The
13 *  image can be a bitmap where each 0 represents the background color and
14 *  each 1 represents the foreground color. Great for font handling. It can
15 *  also be a color image. This is determined by image_depth. The color image
16 *  must be laid out exactly in the same format as the framebuffer. Yes I know
17 *  their are cards with hardware that coverts images of various depths to the
18 *  framebuffer depth. But not every card has this. All images must be rounded
19 *  up to the nearest byte. For example a bitmap 12 bits wide must be two
20 *  bytes width.
21 *
22 *  Tony:
23 *  Incorporate mask tables similar to fbcon-cfb*.c in 2.4 API.  This speeds
24 *  up the code significantly.
25 *
26 *  Code for depths not multiples of BITS_PER_LONG is still kludgy, which is
27 *  still processed a bit at a time.
28 *
29 *  Also need to add code to deal with cards endians that are different than
30 *  the native cpu endians. I also need to deal with MSB position in the word.
31 */
32#include <linux/module.h>
33#include <linux/string.h>
34#include <linux/fb.h>
35#include <asm/types.h>
36#include "fb_draw.h"
37
38#define DEBUG
39
40#ifdef DEBUG
41#define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt,__func__,## args)
42#else
43#define DPRINTK(fmt, args...)
44#endif
45
46static const u32 cfb_tab8_be[] = {
47    0x00000000,0x000000ff,0x0000ff00,0x0000ffff,
48    0x00ff0000,0x00ff00ff,0x00ffff00,0x00ffffff,
49    0xff000000,0xff0000ff,0xff00ff00,0xff00ffff,
50    0xffff0000,0xffff00ff,0xffffff00,0xffffffff
51};
52
53static const u32 cfb_tab8_le[] = {
54    0x00000000,0xff000000,0x00ff0000,0xffff0000,
55    0x0000ff00,0xff00ff00,0x00ffff00,0xffffff00,
56    0x000000ff,0xff0000ff,0x00ff00ff,0xffff00ff,
57    0x0000ffff,0xff00ffff,0x00ffffff,0xffffffff
58};
59
60static const u32 cfb_tab16_be[] = {
61    0x00000000, 0x0000ffff, 0xffff0000, 0xffffffff
62};
63
64static const u32 cfb_tab16_le[] = {
65    0x00000000, 0xffff0000, 0x0000ffff, 0xffffffff
66};
67
68static const u32 cfb_tab32[] = {
69	0x00000000, 0xffffffff
70};
71
72#define FB_WRITEL fb_writel
73#define FB_READL  fb_readl
74
75static inline void color_imageblit(const struct fb_image *image,
76				   struct fb_info *p, u8 __iomem *dst1,
77				   u32 start_index,
78				   u32 pitch_index)
79{
80	/* Draw the penguin */
81	u32 __iomem *dst, *dst2;
82	u32 color = 0, val, shift;
83	int i, n, bpp = p->var.bits_per_pixel;
84	u32 null_bits = 32 - bpp;
85	u32 *palette = (u32 *) p->pseudo_palette;
86	const u8 *src = image->data;
87	u32 bswapmask = fb_compute_bswapmask(p);
88
89	dst2 = (u32 __iomem *) dst1;
90	for (i = image->height; i--; ) {
91		n = image->width;
92		dst = (u32 __iomem *) dst1;
93		shift = 0;
94		val = 0;
95
96		if (start_index) {
97			u32 start_mask = ~fb_shifted_pixels_mask_u32(p,
98						start_index, bswapmask);
99			val = FB_READL(dst) & start_mask;
100			shift = start_index;
101		}
102		while (n--) {
103			if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
104			    p->fix.visual == FB_VISUAL_DIRECTCOLOR )
105				color = palette[*src];
106			else
107				color = *src;
108			color <<= FB_LEFT_POS(p, bpp);
109			val |= FB_SHIFT_HIGH(p, color, shift ^ bswapmask);
110			if (shift >= null_bits) {
111				FB_WRITEL(val, dst++);
112
113				val = (shift == null_bits) ? 0 :
114					FB_SHIFT_LOW(p, color, 32 - shift);
115			}
116			shift += bpp;
117			shift &= (32 - 1);
118			src++;
119		}
120		if (shift) {
121			u32 end_mask = fb_shifted_pixels_mask_u32(p, shift,
122						bswapmask);
123
124			FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
125		}
126		dst1 += p->fix.line_length;
127		if (pitch_index) {
128			dst2 += p->fix.line_length;
129			dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
130
131			start_index += pitch_index;
132			start_index &= 32 - 1;
133		}
134	}
135}
136
137static inline void slow_imageblit(const struct fb_image *image, struct fb_info *p,
138				  u8 __iomem *dst1, u32 fgcolor,
139				  u32 bgcolor,
140				  u32 start_index,
141				  u32 pitch_index)
142{
143	u32 shift, color = 0, bpp = p->var.bits_per_pixel;
144	u32 __iomem *dst, *dst2;
145	u32 val, pitch = p->fix.line_length;
146	u32 null_bits = 32 - bpp;
147	u32 spitch = (image->width+7)/8;
148	const u8 *src = image->data, *s;
149	u32 i, j, l;
150	u32 bswapmask = fb_compute_bswapmask(p);
151
152	dst2 = (u32 __iomem *) dst1;
153	fgcolor <<= FB_LEFT_POS(p, bpp);
154	bgcolor <<= FB_LEFT_POS(p, bpp);
155
156	for (i = image->height; i--; ) {
157		shift = val = 0;
158		l = 8;
159		j = image->width;
160		dst = (u32 __iomem *) dst1;
161		s = src;
162
163		/* write leading bits */
164		if (start_index) {
165			u32 start_mask = ~fb_shifted_pixels_mask_u32(p,
166						start_index, bswapmask);
167			val = FB_READL(dst) & start_mask;
168			shift = start_index;
169		}
170
171		while (j--) {
172			l--;
173			color = (*s & (1 << l)) ? fgcolor : bgcolor;
174			val |= FB_SHIFT_HIGH(p, color, shift ^ bswapmask);
175
176			/* Did the bitshift spill bits to the next long? */
177			if (shift >= null_bits) {
178				FB_WRITEL(val, dst++);
179				val = (shift == null_bits) ? 0 :
180					FB_SHIFT_LOW(p, color, 32 - shift);
181			}
182			shift += bpp;
183			shift &= (32 - 1);
184			if (!l) { l = 8; s++; }
185		}
186
187		/* write trailing bits */
188 		if (shift) {
189			u32 end_mask = fb_shifted_pixels_mask_u32(p, shift,
190						bswapmask);
191
192			FB_WRITEL((FB_READL(dst) & end_mask) | val, dst);
193		}
194
195		dst1 += pitch;
196		src += spitch;
197		if (pitch_index) {
198			dst2 += pitch;
199			dst1 = (u8 __iomem *)((long __force)dst2 & ~(sizeof(u32) - 1));
200			start_index += pitch_index;
201			start_index &= 32 - 1;
202		}
203
204	}
205}
206
207/*
208 * fast_imageblit - optimized monochrome color expansion
209 *
210 * Only if:  bits_per_pixel == 8, 16, or 32
211 *           image->width is divisible by pixel/dword (ppw);
212 *           fix->line_legth is divisible by 4;
213 *           beginning and end of a scanline is dword aligned
214 */
215static inline void fast_imageblit(const struct fb_image *image, struct fb_info *p,
216				  u8 __iomem *dst1, u32 fgcolor,
217				  u32 bgcolor)
218{
219	u32 fgx = fgcolor, bgx = bgcolor, bpp = p->var.bits_per_pixel;
220	u32 ppw = 32/bpp, spitch = (image->width + 7)/8;
221	u32 bit_mask, eorx, shift;
222	const char *s = image->data, *src;
223	u32 __iomem *dst;
224	const u32 *tab = NULL;
225	size_t tablen;
226	u32 colortab[16];
227	int i, j, k;
228
229	switch (bpp) {
230	case 8:
231		tab = fb_be_math(p) ? cfb_tab8_be : cfb_tab8_le;
232		tablen = 16;
233		break;
234	case 16:
235		tab = fb_be_math(p) ? cfb_tab16_be : cfb_tab16_le;
236		tablen = 4;
237		break;
238	case 32:
239		tab = cfb_tab32;
240		tablen = 2;
241		break;
242	default:
243		return;
244	}
245
246	for (i = ppw-1; i--; ) {
247		fgx <<= bpp;
248		bgx <<= bpp;
249		fgx |= fgcolor;
250		bgx |= bgcolor;
251	}
252
253	bit_mask = (1 << ppw) - 1;
254	eorx = fgx ^ bgx;
255	k = image->width/ppw;
256
257	for (i = 0; i < tablen; ++i)
258		colortab[i] = (tab[i] & eorx) ^ bgx;
259
260	for (i = image->height; i--; ) {
261		dst = (u32 __iomem *)dst1;
262		shift = 8;
263		src = s;
264
265		/*
266		 * Manually unroll the per-line copying loop for better
267		 * performance. This works until we processed the last
268		 * completely filled source byte (inclusive).
269		 */
270		switch (ppw) {
271		case 4: /* 8 bpp */
272			for (j = k; j >= 2; j -= 2, ++src) {
273				FB_WRITEL(colortab[(*src >> 4) & bit_mask], dst++);
274				FB_WRITEL(colortab[(*src >> 0) & bit_mask], dst++);
275			}
276			break;
277		case 2: /* 16 bpp */
278			for (j = k; j >= 4; j -= 4, ++src) {
279				FB_WRITEL(colortab[(*src >> 6) & bit_mask], dst++);
280				FB_WRITEL(colortab[(*src >> 4) & bit_mask], dst++);
281				FB_WRITEL(colortab[(*src >> 2) & bit_mask], dst++);
282				FB_WRITEL(colortab[(*src >> 0) & bit_mask], dst++);
283			}
284			break;
285		case 1: /* 32 bpp */
286			for (j = k; j >= 8; j -= 8, ++src) {
287				FB_WRITEL(colortab[(*src >> 7) & bit_mask], dst++);
288				FB_WRITEL(colortab[(*src >> 6) & bit_mask], dst++);
289				FB_WRITEL(colortab[(*src >> 5) & bit_mask], dst++);
290				FB_WRITEL(colortab[(*src >> 4) & bit_mask], dst++);
291				FB_WRITEL(colortab[(*src >> 3) & bit_mask], dst++);
292				FB_WRITEL(colortab[(*src >> 2) & bit_mask], dst++);
293				FB_WRITEL(colortab[(*src >> 1) & bit_mask], dst++);
294				FB_WRITEL(colortab[(*src >> 0) & bit_mask], dst++);
295			}
296			break;
297		}
298
299		/*
300		 * For image widths that are not a multiple of 8, there
301		 * are trailing pixels left on the current line. Print
302		 * them as well.
303		 */
304		for (; j--; ) {
305			shift -= ppw;
306			FB_WRITEL(colortab[(*src >> shift) & bit_mask], dst++);
307			if (!shift) {
308				shift = 8;
309				++src;
310			}
311		}
312
313		dst1 += p->fix.line_length;
314		s += spitch;
315	}
316}
317
318void cfb_imageblit(struct fb_info *p, const struct fb_image *image)
319{
320	u32 fgcolor, bgcolor, start_index, bitstart, pitch_index = 0;
321	u32 bpl = sizeof(u32), bpp = p->var.bits_per_pixel;
322	u32 width = image->width;
323	u32 dx = image->dx, dy = image->dy;
324	u8 __iomem *dst1;
325
326	if (p->state != FBINFO_STATE_RUNNING)
327		return;
328
329	if (p->flags & FBINFO_VIRTFB)
330		fb_warn_once(p, "Framebuffer is not in I/O address space.");
331
332	bitstart = (dy * p->fix.line_length * 8) + (dx * bpp);
333	start_index = bitstart & (32 - 1);
334	pitch_index = (p->fix.line_length & (bpl - 1)) * 8;
335
336	bitstart /= 8;
337	bitstart &= ~(bpl - 1);
338	dst1 = p->screen_base + bitstart;
339
340	if (p->fbops->fb_sync)
341		p->fbops->fb_sync(p);
342
343	if (image->depth == 1) {
344		if (p->fix.visual == FB_VISUAL_TRUECOLOR ||
345		    p->fix.visual == FB_VISUAL_DIRECTCOLOR) {
346			fgcolor = ((u32*)(p->pseudo_palette))[image->fg_color];
347			bgcolor = ((u32*)(p->pseudo_palette))[image->bg_color];
348		} else {
349			fgcolor = image->fg_color;
350			bgcolor = image->bg_color;
351		}
352
353		if (32 % bpp == 0 && !start_index && !pitch_index &&
354		    ((width & (32/bpp-1)) == 0) &&
355		    bpp >= 8 && bpp <= 32)
356			fast_imageblit(image, p, dst1, fgcolor, bgcolor);
357		else
358			slow_imageblit(image, p, dst1, fgcolor, bgcolor,
359					start_index, pitch_index);
360	} else
361		color_imageblit(image, p, dst1, start_index, pitch_index);
362}
363
364EXPORT_SYMBOL(cfb_imageblit);
365
366MODULE_AUTHOR("James Simmons <jsimmons@users.sf.net>");
367MODULE_DESCRIPTION("Generic software accelerated imaging drawing");
368MODULE_LICENSE("GPL");
369
370