xref: /openbmc/linux/drivers/video/fbdev/offb.c (revision 293d5b43)
1 /*
2  *  linux/drivers/video/offb.c -- Open Firmware based frame buffer device
3  *
4  *	Copyright (C) 1997 Geert Uytterhoeven
5  *
6  *  This driver is partly based on the PowerMac console driver:
7  *
8  *	Copyright (C) 1996 Paul Mackerras
9  *
10  *  This file is subject to the terms and conditions of the GNU General Public
11  *  License. See the file COPYING in the main directory of this archive for
12  *  more details.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/errno.h>
18 #include <linux/string.h>
19 #include <linux/mm.h>
20 #include <linux/vmalloc.h>
21 #include <linux/delay.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/interrupt.h>
25 #include <linux/fb.h>
26 #include <linux/init.h>
27 #include <linux/ioport.h>
28 #include <linux/pci.h>
29 #include <asm/io.h>
30 
31 #ifdef CONFIG_PPC32
32 #include <asm/bootx.h>
33 #endif
34 
35 #include "macmodes.h"
36 
37 /* Supported palette hacks */
38 enum {
39 	cmap_unknown,
40 	cmap_simple,		/* ATI Mach64 */
41 	cmap_r128,		/* ATI Rage128 */
42 	cmap_M3A,		/* ATI Rage Mobility M3 Head A */
43 	cmap_M3B,		/* ATI Rage Mobility M3 Head B */
44 	cmap_radeon,		/* ATI Radeon */
45 	cmap_gxt2000,		/* IBM GXT2000 */
46 	cmap_avivo,		/* ATI R5xx */
47 	cmap_qemu,		/* qemu vga */
48 };
49 
50 struct offb_par {
51 	volatile void __iomem *cmap_adr;
52 	volatile void __iomem *cmap_data;
53 	int cmap_type;
54 	int blanked;
55 };
56 
57 struct offb_par default_par;
58 
59 #ifdef CONFIG_PPC32
60 extern boot_infos_t *boot_infos;
61 #endif
62 
63 /* Definitions used by the Avivo palette hack */
64 #define AVIVO_DC_LUT_RW_SELECT                  0x6480
65 #define AVIVO_DC_LUT_RW_MODE                    0x6484
66 #define AVIVO_DC_LUT_RW_INDEX                   0x6488
67 #define AVIVO_DC_LUT_SEQ_COLOR                  0x648c
68 #define AVIVO_DC_LUT_PWL_DATA                   0x6490
69 #define AVIVO_DC_LUT_30_COLOR                   0x6494
70 #define AVIVO_DC_LUT_READ_PIPE_SELECT           0x6498
71 #define AVIVO_DC_LUT_WRITE_EN_MASK              0x649c
72 #define AVIVO_DC_LUT_AUTOFILL                   0x64a0
73 
74 #define AVIVO_DC_LUTA_CONTROL                   0x64c0
75 #define AVIVO_DC_LUTA_BLACK_OFFSET_BLUE         0x64c4
76 #define AVIVO_DC_LUTA_BLACK_OFFSET_GREEN        0x64c8
77 #define AVIVO_DC_LUTA_BLACK_OFFSET_RED          0x64cc
78 #define AVIVO_DC_LUTA_WHITE_OFFSET_BLUE         0x64d0
79 #define AVIVO_DC_LUTA_WHITE_OFFSET_GREEN        0x64d4
80 #define AVIVO_DC_LUTA_WHITE_OFFSET_RED          0x64d8
81 
82 #define AVIVO_DC_LUTB_CONTROL                   0x6cc0
83 #define AVIVO_DC_LUTB_BLACK_OFFSET_BLUE         0x6cc4
84 #define AVIVO_DC_LUTB_BLACK_OFFSET_GREEN        0x6cc8
85 #define AVIVO_DC_LUTB_BLACK_OFFSET_RED          0x6ccc
86 #define AVIVO_DC_LUTB_WHITE_OFFSET_BLUE         0x6cd0
87 #define AVIVO_DC_LUTB_WHITE_OFFSET_GREEN        0x6cd4
88 #define AVIVO_DC_LUTB_WHITE_OFFSET_RED          0x6cd8
89 
90     /*
91      *  Set a single color register. The values supplied are already
92      *  rounded down to the hardware's capabilities (according to the
93      *  entries in the var structure). Return != 0 for invalid regno.
94      */
95 
96 static int offb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
97 			  u_int transp, struct fb_info *info)
98 {
99 	struct offb_par *par = (struct offb_par *) info->par;
100 
101 	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
102 		u32 *pal = info->pseudo_palette;
103 		u32 cr = red >> (16 - info->var.red.length);
104 		u32 cg = green >> (16 - info->var.green.length);
105 		u32 cb = blue >> (16 - info->var.blue.length);
106 		u32 value;
107 
108 		if (regno >= 16)
109 			return -EINVAL;
110 
111 		value = (cr << info->var.red.offset) |
112 			(cg << info->var.green.offset) |
113 			(cb << info->var.blue.offset);
114 		if (info->var.transp.length > 0) {
115 			u32 mask = (1 << info->var.transp.length) - 1;
116 			mask <<= info->var.transp.offset;
117 			value |= mask;
118 		}
119 		pal[regno] = value;
120 		return 0;
121 	}
122 
123 	if (regno > 255)
124 		return -EINVAL;
125 
126 	red >>= 8;
127 	green >>= 8;
128 	blue >>= 8;
129 
130 	if (!par->cmap_adr)
131 		return 0;
132 
133 	switch (par->cmap_type) {
134 	case cmap_simple:
135 		writeb(regno, par->cmap_adr);
136 		writeb(red, par->cmap_data);
137 		writeb(green, par->cmap_data);
138 		writeb(blue, par->cmap_data);
139 		break;
140 	case cmap_M3A:
141 		/* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
142 		out_le32(par->cmap_adr + 0x58,
143 			 in_le32(par->cmap_adr + 0x58) & ~0x20);
144 	case cmap_r128:
145 		/* Set palette index & data */
146 		out_8(par->cmap_adr + 0xb0, regno);
147 		out_le32(par->cmap_adr + 0xb4,
148 			 (red << 16 | green << 8 | blue));
149 		break;
150 	case cmap_M3B:
151 		/* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
152 		out_le32(par->cmap_adr + 0x58,
153 			 in_le32(par->cmap_adr + 0x58) | 0x20);
154 		/* Set palette index & data */
155 		out_8(par->cmap_adr + 0xb0, regno);
156 		out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
157 		break;
158 	case cmap_radeon:
159 		/* Set palette index & data (could be smarter) */
160 		out_8(par->cmap_adr + 0xb0, regno);
161 		out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
162 		break;
163 	case cmap_gxt2000:
164 		out_le32(((unsigned __iomem *) par->cmap_adr) + regno,
165 			 (red << 16 | green << 8 | blue));
166 		break;
167 	case cmap_avivo:
168 		/* Write to both LUTs for now */
169 		writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
170 		writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
171 		writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
172 		       par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
173 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
174 		writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
175 		writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
176 		       par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
177 		break;
178 	}
179 
180 	return 0;
181 }
182 
183     /*
184      *  Blank the display.
185      */
186 
187 static int offb_blank(int blank, struct fb_info *info)
188 {
189 	struct offb_par *par = (struct offb_par *) info->par;
190 	int i, j;
191 
192 	if (!par->cmap_adr)
193 		return 0;
194 
195 	if (!par->blanked)
196 		if (!blank)
197 			return 0;
198 
199 	par->blanked = blank;
200 
201 	if (blank)
202 		for (i = 0; i < 256; i++) {
203 			switch (par->cmap_type) {
204 			case cmap_simple:
205 				writeb(i, par->cmap_adr);
206 				for (j = 0; j < 3; j++)
207 					writeb(0, par->cmap_data);
208 				break;
209 			case cmap_M3A:
210 				/* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
211 				out_le32(par->cmap_adr + 0x58,
212 					 in_le32(par->cmap_adr + 0x58) & ~0x20);
213 			case cmap_r128:
214 				/* Set palette index & data */
215 				out_8(par->cmap_adr + 0xb0, i);
216 				out_le32(par->cmap_adr + 0xb4, 0);
217 				break;
218 			case cmap_M3B:
219 				/* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
220 				out_le32(par->cmap_adr + 0x58,
221 					 in_le32(par->cmap_adr + 0x58) | 0x20);
222 				/* Set palette index & data */
223 				out_8(par->cmap_adr + 0xb0, i);
224 				out_le32(par->cmap_adr + 0xb4, 0);
225 				break;
226 			case cmap_radeon:
227 				out_8(par->cmap_adr + 0xb0, i);
228 				out_le32(par->cmap_adr + 0xb4, 0);
229 				break;
230 			case cmap_gxt2000:
231 				out_le32(((unsigned __iomem *) par->cmap_adr) + i,
232 					 0);
233 				break;
234 			case cmap_avivo:
235 				writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
236 				writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
237 				writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
238 				writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
239 				writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
240 				writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
241 				break;
242 			}
243 	} else
244 		fb_set_cmap(&info->cmap, info);
245 	return 0;
246 }
247 
248 static int offb_set_par(struct fb_info *info)
249 {
250 	struct offb_par *par = (struct offb_par *) info->par;
251 
252 	/* On avivo, initialize palette control */
253 	if (par->cmap_type == cmap_avivo) {
254 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_CONTROL);
255 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_BLUE);
256 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_GREEN);
257 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_RED);
258 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_BLUE);
259 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_GREEN);
260 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_RED);
261 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_CONTROL);
262 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_BLUE);
263 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_GREEN);
264 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_RED);
265 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_BLUE);
266 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_GREEN);
267 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_RED);
268 		writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
269 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
270 		writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
271 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
272 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
273 		writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
274 	}
275 	return 0;
276 }
277 
278 static void offb_destroy(struct fb_info *info)
279 {
280 	if (info->screen_base)
281 		iounmap(info->screen_base);
282 	release_mem_region(info->apertures->ranges[0].base, info->apertures->ranges[0].size);
283 	framebuffer_release(info);
284 }
285 
286 static struct fb_ops offb_ops = {
287 	.owner		= THIS_MODULE,
288 	.fb_destroy	= offb_destroy,
289 	.fb_setcolreg	= offb_setcolreg,
290 	.fb_set_par	= offb_set_par,
291 	.fb_blank	= offb_blank,
292 	.fb_fillrect	= cfb_fillrect,
293 	.fb_copyarea	= cfb_copyarea,
294 	.fb_imageblit	= cfb_imageblit,
295 };
296 
297 static void __iomem *offb_map_reg(struct device_node *np, int index,
298 				  unsigned long offset, unsigned long size)
299 {
300 	const __be32 *addrp;
301 	u64 asize, taddr;
302 	unsigned int flags;
303 
304 	addrp = of_get_pci_address(np, index, &asize, &flags);
305 	if (addrp == NULL)
306 		addrp = of_get_address(np, index, &asize, &flags);
307 	if (addrp == NULL)
308 		return NULL;
309 	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
310 		return NULL;
311 	if ((offset + size) > asize)
312 		return NULL;
313 	taddr = of_translate_address(np, addrp);
314 	if (taddr == OF_BAD_ADDR)
315 		return NULL;
316 	return ioremap(taddr + offset, size);
317 }
318 
319 static void offb_init_palette_hacks(struct fb_info *info, struct device_node *dp,
320 				    const char *name, unsigned long address)
321 {
322 	struct offb_par *par = (struct offb_par *) info->par;
323 
324 	if (dp && !strncmp(name, "ATY,Rage128", 11)) {
325 		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
326 		if (par->cmap_adr)
327 			par->cmap_type = cmap_r128;
328 	} else if (dp && (!strncmp(name, "ATY,RageM3pA", 12)
329 			  || !strncmp(name, "ATY,RageM3p12A", 14))) {
330 		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
331 		if (par->cmap_adr)
332 			par->cmap_type = cmap_M3A;
333 	} else if (dp && !strncmp(name, "ATY,RageM3pB", 12)) {
334 		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
335 		if (par->cmap_adr)
336 			par->cmap_type = cmap_M3B;
337 	} else if (dp && !strncmp(name, "ATY,Rage6", 9)) {
338 		par->cmap_adr = offb_map_reg(dp, 1, 0, 0x1fff);
339 		if (par->cmap_adr)
340 			par->cmap_type = cmap_radeon;
341 	} else if (!strncmp(name, "ATY,", 4)) {
342 		unsigned long base = address & 0xff000000UL;
343 		par->cmap_adr =
344 			ioremap(base + 0x7ff000, 0x1000) + 0xcc0;
345 		par->cmap_data = par->cmap_adr + 1;
346 		par->cmap_type = cmap_simple;
347 	} else if (dp && (of_device_is_compatible(dp, "pci1014,b7") ||
348 			  of_device_is_compatible(dp, "pci1014,21c"))) {
349 		par->cmap_adr = offb_map_reg(dp, 0, 0x6000, 0x1000);
350 		if (par->cmap_adr)
351 			par->cmap_type = cmap_gxt2000;
352 	} else if (dp && !strncmp(name, "vga,Display-", 12)) {
353 		/* Look for AVIVO initialized by SLOF */
354 		struct device_node *pciparent = of_get_parent(dp);
355 		const u32 *vid, *did;
356 		vid = of_get_property(pciparent, "vendor-id", NULL);
357 		did = of_get_property(pciparent, "device-id", NULL);
358 		/* This will match most R5xx */
359 		if (vid && did && *vid == 0x1002 &&
360 		    ((*did >= 0x7100 && *did < 0x7800) ||
361 		     (*did >= 0x9400))) {
362 			par->cmap_adr = offb_map_reg(pciparent, 2, 0, 0x10000);
363 			if (par->cmap_adr)
364 				par->cmap_type = cmap_avivo;
365 		}
366 		of_node_put(pciparent);
367 	} else if (dp && of_device_is_compatible(dp, "qemu,std-vga")) {
368 #ifdef __BIG_ENDIAN
369 		const __be32 io_of_addr[3] = { 0x01000000, 0x0, 0x0 };
370 #else
371 		const __be32 io_of_addr[3] = { 0x00000001, 0x0, 0x0 };
372 #endif
373 		u64 io_addr = of_translate_address(dp, io_of_addr);
374 		if (io_addr != OF_BAD_ADDR) {
375 			par->cmap_adr = ioremap(io_addr + 0x3c8, 2);
376 			if (par->cmap_adr) {
377 				par->cmap_type = cmap_simple;
378 				par->cmap_data = par->cmap_adr + 1;
379 			}
380 		}
381 	}
382 	info->fix.visual = (par->cmap_type != cmap_unknown) ?
383 		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_STATIC_PSEUDOCOLOR;
384 }
385 
386 static void __init offb_init_fb(const char *name, const char *full_name,
387 				int width, int height, int depth,
388 				int pitch, unsigned long address,
389 				int foreign_endian, struct device_node *dp)
390 {
391 	unsigned long res_size = pitch * height;
392 	struct offb_par *par = &default_par;
393 	unsigned long res_start = address;
394 	struct fb_fix_screeninfo *fix;
395 	struct fb_var_screeninfo *var;
396 	struct fb_info *info;
397 
398 	if (!request_mem_region(res_start, res_size, "offb"))
399 		return;
400 
401 	printk(KERN_INFO
402 	       "Using unsupported %dx%d %s at %lx, depth=%d, pitch=%d\n",
403 	       width, height, name, address, depth, pitch);
404 	if (depth != 8 && depth != 15 && depth != 16 && depth != 32) {
405 		printk(KERN_ERR "%s: can't use depth = %d\n", full_name,
406 		       depth);
407 		release_mem_region(res_start, res_size);
408 		return;
409 	}
410 
411 	info = framebuffer_alloc(sizeof(u32) * 16, NULL);
412 
413 	if (info == 0) {
414 		release_mem_region(res_start, res_size);
415 		return;
416 	}
417 
418 	fix = &info->fix;
419 	var = &info->var;
420 	info->par = par;
421 
422 	strcpy(fix->id, "OFfb ");
423 	strncat(fix->id, name, sizeof(fix->id) - sizeof("OFfb "));
424 	fix->id[sizeof(fix->id) - 1] = '\0';
425 
426 	var->xres = var->xres_virtual = width;
427 	var->yres = var->yres_virtual = height;
428 	fix->line_length = pitch;
429 
430 	fix->smem_start = address;
431 	fix->smem_len = pitch * height;
432 	fix->type = FB_TYPE_PACKED_PIXELS;
433 	fix->type_aux = 0;
434 
435 	par->cmap_type = cmap_unknown;
436 	if (depth == 8)
437 		offb_init_palette_hacks(info, dp, name, address);
438 	else
439 		fix->visual = FB_VISUAL_TRUECOLOR;
440 
441 	var->xoffset = var->yoffset = 0;
442 	switch (depth) {
443 	case 8:
444 		var->bits_per_pixel = 8;
445 		var->red.offset = 0;
446 		var->red.length = 8;
447 		var->green.offset = 0;
448 		var->green.length = 8;
449 		var->blue.offset = 0;
450 		var->blue.length = 8;
451 		var->transp.offset = 0;
452 		var->transp.length = 0;
453 		break;
454 	case 15:		/* RGB 555 */
455 		var->bits_per_pixel = 16;
456 		var->red.offset = 10;
457 		var->red.length = 5;
458 		var->green.offset = 5;
459 		var->green.length = 5;
460 		var->blue.offset = 0;
461 		var->blue.length = 5;
462 		var->transp.offset = 0;
463 		var->transp.length = 0;
464 		break;
465 	case 16:		/* RGB 565 */
466 		var->bits_per_pixel = 16;
467 		var->red.offset = 11;
468 		var->red.length = 5;
469 		var->green.offset = 5;
470 		var->green.length = 6;
471 		var->blue.offset = 0;
472 		var->blue.length = 5;
473 		var->transp.offset = 0;
474 		var->transp.length = 0;
475 		break;
476 	case 32:		/* RGB 888 */
477 		var->bits_per_pixel = 32;
478 		var->red.offset = 16;
479 		var->red.length = 8;
480 		var->green.offset = 8;
481 		var->green.length = 8;
482 		var->blue.offset = 0;
483 		var->blue.length = 8;
484 		var->transp.offset = 24;
485 		var->transp.length = 8;
486 		break;
487 	}
488 	var->red.msb_right = var->green.msb_right = var->blue.msb_right =
489 	    var->transp.msb_right = 0;
490 	var->grayscale = 0;
491 	var->nonstd = 0;
492 	var->activate = 0;
493 	var->height = var->width = -1;
494 	var->pixclock = 10000;
495 	var->left_margin = var->right_margin = 16;
496 	var->upper_margin = var->lower_margin = 16;
497 	var->hsync_len = var->vsync_len = 8;
498 	var->sync = 0;
499 	var->vmode = FB_VMODE_NONINTERLACED;
500 
501 	/* set offb aperture size for generic probing */
502 	info->apertures = alloc_apertures(1);
503 	if (!info->apertures)
504 		goto out_aper;
505 	info->apertures->ranges[0].base = address;
506 	info->apertures->ranges[0].size = fix->smem_len;
507 
508 	info->fbops = &offb_ops;
509 	info->screen_base = ioremap(address, fix->smem_len);
510 	info->pseudo_palette = (void *) (info + 1);
511 	info->flags = FBINFO_DEFAULT | FBINFO_MISC_FIRMWARE | foreign_endian;
512 
513 	fb_alloc_cmap(&info->cmap, 256, 0);
514 
515 	if (register_framebuffer(info) < 0)
516 		goto out_err;
517 
518 	fb_info(info, "Open Firmware frame buffer device on %s\n", full_name);
519 	return;
520 
521 out_err:
522 	iounmap(info->screen_base);
523 out_aper:
524 	iounmap(par->cmap_adr);
525 	par->cmap_adr = NULL;
526 	framebuffer_release(info);
527 	release_mem_region(res_start, res_size);
528 }
529 
530 
531 static void __init offb_init_nodriver(struct device_node *dp, int no_real_node)
532 {
533 	unsigned int len;
534 	int i, width = 640, height = 480, depth = 8, pitch = 640;
535 	unsigned int flags, rsize, addr_prop = 0;
536 	unsigned long max_size = 0;
537 	u64 rstart, address = OF_BAD_ADDR;
538 	const __be32 *pp, *addrp, *up;
539 	u64 asize;
540 	int foreign_endian = 0;
541 
542 #ifdef __BIG_ENDIAN
543 	if (of_get_property(dp, "little-endian", NULL))
544 		foreign_endian = FBINFO_FOREIGN_ENDIAN;
545 #else
546 	if (of_get_property(dp, "big-endian", NULL))
547 		foreign_endian = FBINFO_FOREIGN_ENDIAN;
548 #endif
549 
550 	pp = of_get_property(dp, "linux,bootx-depth", &len);
551 	if (pp == NULL)
552 		pp = of_get_property(dp, "depth", &len);
553 	if (pp && len == sizeof(u32))
554 		depth = be32_to_cpup(pp);
555 
556 	pp = of_get_property(dp, "linux,bootx-width", &len);
557 	if (pp == NULL)
558 		pp = of_get_property(dp, "width", &len);
559 	if (pp && len == sizeof(u32))
560 		width = be32_to_cpup(pp);
561 
562 	pp = of_get_property(dp, "linux,bootx-height", &len);
563 	if (pp == NULL)
564 		pp = of_get_property(dp, "height", &len);
565 	if (pp && len == sizeof(u32))
566 		height = be32_to_cpup(pp);
567 
568 	pp = of_get_property(dp, "linux,bootx-linebytes", &len);
569 	if (pp == NULL)
570 		pp = of_get_property(dp, "linebytes", &len);
571 	if (pp && len == sizeof(u32) && (*pp != 0xffffffffu))
572 		pitch = be32_to_cpup(pp);
573 	else
574 		pitch = width * ((depth + 7) / 8);
575 
576 	rsize = (unsigned long)pitch * (unsigned long)height;
577 
578 	/* Ok, now we try to figure out the address of the framebuffer.
579 	 *
580 	 * Unfortunately, Open Firmware doesn't provide a standard way to do
581 	 * so. All we can do is a dodgy heuristic that happens to work in
582 	 * practice. On most machines, the "address" property contains what
583 	 * we need, though not on Matrox cards found in IBM machines. What I've
584 	 * found that appears to give good results is to go through the PCI
585 	 * ranges and pick one that is both big enough and if possible encloses
586 	 * the "address" property. If none match, we pick the biggest
587 	 */
588 	up = of_get_property(dp, "linux,bootx-addr", &len);
589 	if (up == NULL)
590 		up = of_get_property(dp, "address", &len);
591 	if (up && len == sizeof(u32))
592 		addr_prop = *up;
593 
594 	/* Hack for when BootX is passing us */
595 	if (no_real_node)
596 		goto skip_addr;
597 
598 	for (i = 0; (addrp = of_get_address(dp, i, &asize, &flags))
599 		     != NULL; i++) {
600 		int match_addrp = 0;
601 
602 		if (!(flags & IORESOURCE_MEM))
603 			continue;
604 		if (asize < rsize)
605 			continue;
606 		rstart = of_translate_address(dp, addrp);
607 		if (rstart == OF_BAD_ADDR)
608 			continue;
609 		if (addr_prop && (rstart <= addr_prop) &&
610 		    ((rstart + asize) >= (addr_prop + rsize)))
611 			match_addrp = 1;
612 		if (match_addrp) {
613 			address = addr_prop;
614 			break;
615 		}
616 		if (rsize > max_size) {
617 			max_size = rsize;
618 			address = OF_BAD_ADDR;
619  		}
620 
621 		if (address == OF_BAD_ADDR)
622 			address = rstart;
623 	}
624  skip_addr:
625 	if (address == OF_BAD_ADDR && addr_prop)
626 		address = (u64)addr_prop;
627 	if (address != OF_BAD_ADDR) {
628 		/* kludge for valkyrie */
629 		if (strcmp(dp->name, "valkyrie") == 0)
630 			address += 0x1000;
631 		offb_init_fb(no_real_node ? "bootx" : dp->name,
632 			     no_real_node ? "display" : dp->full_name,
633 			     width, height, depth, pitch, address,
634 			     foreign_endian, no_real_node ? NULL : dp);
635 	}
636 }
637 
638 static int __init offb_init(void)
639 {
640 	struct device_node *dp = NULL, *boot_disp = NULL;
641 
642 	if (fb_get_options("offb", NULL))
643 		return -ENODEV;
644 
645 	/* Check if we have a MacOS display without a node spec */
646 	if (of_get_property(of_chosen, "linux,bootx-noscreen", NULL) != NULL) {
647 		/* The old code tried to work out which node was the MacOS
648 		 * display based on the address. I'm dropping that since the
649 		 * lack of a node spec only happens with old BootX versions
650 		 * (users can update) and with this code, they'll still get
651 		 * a display (just not the palette hacks).
652 		 */
653 		offb_init_nodriver(of_chosen, 1);
654 	}
655 
656 	for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
657 		if (of_get_property(dp, "linux,opened", NULL) &&
658 		    of_get_property(dp, "linux,boot-display", NULL)) {
659 			boot_disp = dp;
660 			offb_init_nodriver(dp, 0);
661 		}
662 	}
663 	for (dp = NULL; (dp = of_find_node_by_type(dp, "display"));) {
664 		if (of_get_property(dp, "linux,opened", NULL) &&
665 		    dp != boot_disp)
666 			offb_init_nodriver(dp, 0);
667 	}
668 
669 	return 0;
670 }
671 
672 
673 module_init(offb_init);
674 MODULE_LICENSE("GPL");
675