xref: /linux/drivers/video/fbdev/offb.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
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/aperture.h>
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/string.h>
20 #include <linux/mm.h>
21 #include <linux/vmalloc.h>
22 #include <linux/delay.h>
23 #include <linux/of.h>
24 #include <linux/of_address.h>
25 #include <linux/interrupt.h>
26 #include <linux/fb.h>
27 #include <linux/init.h>
28 #include <linux/ioport.h>
29 #include <linux/pci.h>
30 #include <linux/platform_device.h>
31 #include <asm/io.h>
32 
33 #ifdef CONFIG_PPC32
34 #include <asm/bootx.h>
35 #endif
36 
37 #include "macmodes.h"
38 
39 /* Supported palette hacks */
40 enum {
41 	cmap_unknown,
42 	cmap_simple,		/* ATI Mach64 */
43 	cmap_r128,		/* ATI Rage128 */
44 	cmap_M3A,		/* ATI Rage Mobility M3 Head A */
45 	cmap_M3B,		/* ATI Rage Mobility M3 Head B */
46 	cmap_radeon,		/* ATI Radeon */
47 	cmap_gxt2000,		/* IBM GXT2000 */
48 	cmap_avivo,		/* ATI R5xx */
49 	cmap_qemu,		/* qemu vga */
50 };
51 
52 struct offb_par {
53 	volatile void __iomem *cmap_adr;
54 	volatile void __iomem *cmap_data;
55 	int cmap_type;
56 	int blanked;
57 	u32 pseudo_palette[16];
58 	resource_size_t base;
59 	resource_size_t size;
60 };
61 
62 #ifdef CONFIG_PPC32
63 extern boot_infos_t *boot_infos;
64 #endif
65 
66 /* Definitions used by the Avivo palette hack */
67 #define AVIVO_DC_LUT_RW_SELECT                  0x6480
68 #define AVIVO_DC_LUT_RW_MODE                    0x6484
69 #define AVIVO_DC_LUT_RW_INDEX                   0x6488
70 #define AVIVO_DC_LUT_SEQ_COLOR                  0x648c
71 #define AVIVO_DC_LUT_PWL_DATA                   0x6490
72 #define AVIVO_DC_LUT_30_COLOR                   0x6494
73 #define AVIVO_DC_LUT_READ_PIPE_SELECT           0x6498
74 #define AVIVO_DC_LUT_WRITE_EN_MASK              0x649c
75 #define AVIVO_DC_LUT_AUTOFILL                   0x64a0
76 
77 #define AVIVO_DC_LUTA_CONTROL                   0x64c0
78 #define AVIVO_DC_LUTA_BLACK_OFFSET_BLUE         0x64c4
79 #define AVIVO_DC_LUTA_BLACK_OFFSET_GREEN        0x64c8
80 #define AVIVO_DC_LUTA_BLACK_OFFSET_RED          0x64cc
81 #define AVIVO_DC_LUTA_WHITE_OFFSET_BLUE         0x64d0
82 #define AVIVO_DC_LUTA_WHITE_OFFSET_GREEN        0x64d4
83 #define AVIVO_DC_LUTA_WHITE_OFFSET_RED          0x64d8
84 
85 #define AVIVO_DC_LUTB_CONTROL                   0x6cc0
86 #define AVIVO_DC_LUTB_BLACK_OFFSET_BLUE         0x6cc4
87 #define AVIVO_DC_LUTB_BLACK_OFFSET_GREEN        0x6cc8
88 #define AVIVO_DC_LUTB_BLACK_OFFSET_RED          0x6ccc
89 #define AVIVO_DC_LUTB_WHITE_OFFSET_BLUE         0x6cd0
90 #define AVIVO_DC_LUTB_WHITE_OFFSET_GREEN        0x6cd4
91 #define AVIVO_DC_LUTB_WHITE_OFFSET_RED          0x6cd8
92 
93     /*
94      *  Set a single color register. The values supplied are already
95      *  rounded down to the hardware's capabilities (according to the
96      *  entries in the var structure). Return != 0 for invalid regno.
97      */
98 
99 static int offb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
100 			  u_int transp, struct fb_info *info)
101 {
102 	struct offb_par *par = (struct offb_par *) info->par;
103 
104 	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
105 		u32 *pal = info->pseudo_palette;
106 		u32 cr = red >> (16 - info->var.red.length);
107 		u32 cg = green >> (16 - info->var.green.length);
108 		u32 cb = blue >> (16 - info->var.blue.length);
109 		u32 value;
110 
111 		if (regno >= 16)
112 			return -EINVAL;
113 
114 		value = (cr << info->var.red.offset) |
115 			(cg << info->var.green.offset) |
116 			(cb << info->var.blue.offset);
117 		if (info->var.transp.length > 0) {
118 			u32 mask = (1 << info->var.transp.length) - 1;
119 			mask <<= info->var.transp.offset;
120 			value |= mask;
121 		}
122 		pal[regno] = value;
123 		return 0;
124 	}
125 
126 	if (regno > 255)
127 		return -EINVAL;
128 
129 	red >>= 8;
130 	green >>= 8;
131 	blue >>= 8;
132 
133 	if (!par->cmap_adr)
134 		return 0;
135 
136 	switch (par->cmap_type) {
137 	case cmap_simple:
138 		writeb(regno, par->cmap_adr);
139 		writeb(red, par->cmap_data);
140 		writeb(green, par->cmap_data);
141 		writeb(blue, par->cmap_data);
142 		break;
143 	case cmap_M3A:
144 		/* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
145 		out_le32(par->cmap_adr + 0x58,
146 			 in_le32(par->cmap_adr + 0x58) & ~0x20);
147 		fallthrough;
148 	case cmap_r128:
149 		/* Set palette index & data */
150 		out_8(par->cmap_adr + 0xb0, regno);
151 		out_le32(par->cmap_adr + 0xb4,
152 			 (red << 16 | green << 8 | blue));
153 		break;
154 	case cmap_M3B:
155 		/* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
156 		out_le32(par->cmap_adr + 0x58,
157 			 in_le32(par->cmap_adr + 0x58) | 0x20);
158 		/* Set palette index & data */
159 		out_8(par->cmap_adr + 0xb0, regno);
160 		out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
161 		break;
162 	case cmap_radeon:
163 		/* Set palette index & data (could be smarter) */
164 		out_8(par->cmap_adr + 0xb0, regno);
165 		out_le32(par->cmap_adr + 0xb4, (red << 16 | green << 8 | blue));
166 		break;
167 	case cmap_gxt2000:
168 		out_le32(((unsigned __iomem *) par->cmap_adr) + regno,
169 			 (red << 16 | green << 8 | blue));
170 		break;
171 	case cmap_avivo:
172 		/* Write to both LUTs for now */
173 		writel(1, 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 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
178 		writeb(regno, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
179 		writel(((red) << 22) | ((green) << 12) | ((blue) << 2),
180 		       par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
181 		break;
182 	}
183 
184 	return 0;
185 }
186 
187     /*
188      *  Blank the display.
189      */
190 
191 static int offb_blank(int blank, struct fb_info *info)
192 {
193 	struct offb_par *par = (struct offb_par *) info->par;
194 	int i, j;
195 
196 	if (!par->cmap_adr)
197 		return 0;
198 
199 	if (!par->blanked)
200 		if (!blank)
201 			return 0;
202 
203 	par->blanked = blank;
204 
205 	if (blank)
206 		for (i = 0; i < 256; i++) {
207 			switch (par->cmap_type) {
208 			case cmap_simple:
209 				writeb(i, par->cmap_adr);
210 				for (j = 0; j < 3; j++)
211 					writeb(0, par->cmap_data);
212 				break;
213 			case cmap_M3A:
214 				/* Clear PALETTE_ACCESS_CNTL in DAC_CNTL */
215 				out_le32(par->cmap_adr + 0x58,
216 					 in_le32(par->cmap_adr + 0x58) & ~0x20);
217 				fallthrough;
218 			case cmap_r128:
219 				/* Set palette index & data */
220 				out_8(par->cmap_adr + 0xb0, i);
221 				out_le32(par->cmap_adr + 0xb4, 0);
222 				break;
223 			case cmap_M3B:
224 				/* Set PALETTE_ACCESS_CNTL in DAC_CNTL */
225 				out_le32(par->cmap_adr + 0x58,
226 					 in_le32(par->cmap_adr + 0x58) | 0x20);
227 				/* Set palette index & data */
228 				out_8(par->cmap_adr + 0xb0, i);
229 				out_le32(par->cmap_adr + 0xb4, 0);
230 				break;
231 			case cmap_radeon:
232 				out_8(par->cmap_adr + 0xb0, i);
233 				out_le32(par->cmap_adr + 0xb4, 0);
234 				break;
235 			case cmap_gxt2000:
236 				out_le32(((unsigned __iomem *) par->cmap_adr) + i,
237 					 0);
238 				break;
239 			case cmap_avivo:
240 				writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
241 				writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
242 				writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
243 				writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
244 				writeb(i, par->cmap_adr + AVIVO_DC_LUT_RW_INDEX);
245 				writel(0, par->cmap_adr + AVIVO_DC_LUT_30_COLOR);
246 				break;
247 			}
248 	} else
249 		fb_set_cmap(&info->cmap, info);
250 	return 0;
251 }
252 
253 static int offb_set_par(struct fb_info *info)
254 {
255 	struct offb_par *par = (struct offb_par *) info->par;
256 
257 	/* On avivo, initialize palette control */
258 	if (par->cmap_type == cmap_avivo) {
259 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_CONTROL);
260 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_BLUE);
261 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_GREEN);
262 		writel(0, par->cmap_adr + AVIVO_DC_LUTA_BLACK_OFFSET_RED);
263 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_BLUE);
264 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_GREEN);
265 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTA_WHITE_OFFSET_RED);
266 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_CONTROL);
267 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_BLUE);
268 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_GREEN);
269 		writel(0, par->cmap_adr + AVIVO_DC_LUTB_BLACK_OFFSET_RED);
270 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_BLUE);
271 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_GREEN);
272 		writel(0x0000ffff, par->cmap_adr + AVIVO_DC_LUTB_WHITE_OFFSET_RED);
273 		writel(1, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
274 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
275 		writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
276 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_SELECT);
277 		writel(0, par->cmap_adr + AVIVO_DC_LUT_RW_MODE);
278 		writel(0x0000003f, par->cmap_adr + AVIVO_DC_LUT_WRITE_EN_MASK);
279 	}
280 	return 0;
281 }
282 
283 static void offb_destroy(struct fb_info *info)
284 {
285 	struct offb_par *par = info->par;
286 
287 	if (info->screen_base)
288 		iounmap(info->screen_base);
289 	release_mem_region(par->base, par->size);
290 	fb_dealloc_cmap(&info->cmap);
291 	framebuffer_release(info);
292 }
293 
294 static const struct fb_ops offb_ops = {
295 	.owner		= THIS_MODULE,
296 	FB_DEFAULT_IOMEM_OPS,
297 	.fb_destroy	= offb_destroy,
298 	.fb_setcolreg	= offb_setcolreg,
299 	.fb_set_par	= offb_set_par,
300 	.fb_blank	= offb_blank,
301 };
302 
303 static void __iomem *offb_map_reg(struct device_node *np, int index,
304 				  unsigned long offset, unsigned long size)
305 {
306 	const __be32 *addrp;
307 	u64 asize, taddr;
308 	unsigned int flags;
309 
310 	addrp = of_get_pci_address(np, index, &asize, &flags);
311 	if (addrp == NULL)
312 		addrp = of_get_address(np, index, &asize, &flags);
313 	if (addrp == NULL)
314 		return NULL;
315 	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
316 		return NULL;
317 	if ((offset + size) > asize)
318 		return NULL;
319 	taddr = of_translate_address(np, addrp);
320 	if (taddr == OF_BAD_ADDR)
321 		return NULL;
322 	return ioremap(taddr + offset, size);
323 }
324 
325 static void offb_init_palette_hacks(struct fb_info *info, struct device_node *dp,
326 				    unsigned long address)
327 {
328 	struct offb_par *par = (struct offb_par *) info->par;
329 
330 	if (of_node_name_prefix(dp, "ATY,Rage128")) {
331 		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
332 		if (par->cmap_adr)
333 			par->cmap_type = cmap_r128;
334 	} else if (of_node_name_prefix(dp, "ATY,RageM3pA") ||
335 		   of_node_name_prefix(dp, "ATY,RageM3p12A")) {
336 		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
337 		if (par->cmap_adr)
338 			par->cmap_type = cmap_M3A;
339 	} else if (of_node_name_prefix(dp, "ATY,RageM3pB")) {
340 		par->cmap_adr = offb_map_reg(dp, 2, 0, 0x1fff);
341 		if (par->cmap_adr)
342 			par->cmap_type = cmap_M3B;
343 	} else if (of_node_name_prefix(dp, "ATY,Rage6")) {
344 		par->cmap_adr = offb_map_reg(dp, 1, 0, 0x1fff);
345 		if (par->cmap_adr)
346 			par->cmap_type = cmap_radeon;
347 	} else if (of_node_name_prefix(dp, "ATY,")) {
348 		unsigned long base = address & 0xff000000UL;
349 		par->cmap_adr =
350 			ioremap(base + 0x7ff000, 0x1000) + 0xcc0;
351 		par->cmap_data = par->cmap_adr + 1;
352 		par->cmap_type = cmap_simple;
353 	} else if (dp && (of_device_is_compatible(dp, "pci1014,b7") ||
354 			  of_device_is_compatible(dp, "pci1014,21c"))) {
355 		par->cmap_adr = offb_map_reg(dp, 0, 0x6000, 0x1000);
356 		if (par->cmap_adr)
357 			par->cmap_type = cmap_gxt2000;
358 	} else if (of_node_name_prefix(dp, "vga,Display-")) {
359 		/* Look for AVIVO initialized by SLOF */
360 		struct device_node *pciparent __free(device_node) = of_get_parent(dp);
361 		const u32 *vid, *did;
362 		vid = of_get_property(pciparent, "vendor-id", NULL);
363 		did = of_get_property(pciparent, "device-id", NULL);
364 		/* This will match most R5xx */
365 		if (vid && did && *vid == 0x1002 &&
366 		    ((*did >= 0x7100 && *did < 0x7800) ||
367 		     (*did >= 0x9400))) {
368 			par->cmap_adr = offb_map_reg(pciparent, 2, 0, 0x10000);
369 			if (par->cmap_adr)
370 				par->cmap_type = cmap_avivo;
371 		}
372 	} else if (dp && of_device_is_compatible(dp, "qemu,std-vga")) {
373 #ifdef __BIG_ENDIAN
374 		const __be32 io_of_addr[3] = { 0x01000000, 0x0, 0x0 };
375 #else
376 		const __be32 io_of_addr[3] = { 0x00000001, 0x0, 0x0 };
377 #endif
378 		u64 io_addr = of_translate_address(dp, io_of_addr);
379 		if (io_addr != OF_BAD_ADDR) {
380 			par->cmap_adr = ioremap(io_addr + 0x3c8, 2);
381 			if (par->cmap_adr) {
382 				par->cmap_type = cmap_simple;
383 				par->cmap_data = par->cmap_adr + 1;
384 			}
385 		}
386 	}
387 	info->fix.visual = (par->cmap_type != cmap_unknown) ?
388 		FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_STATIC_PSEUDOCOLOR;
389 }
390 
391 static void offb_init_fb(struct platform_device *parent, const char *name,
392 			 int width, int height, int depth,
393 			 int pitch, unsigned long address,
394 			 int foreign_endian, struct device_node *dp)
395 {
396 	unsigned long res_size = pitch * height;
397 	unsigned long res_start = address;
398 	struct fb_fix_screeninfo *fix;
399 	struct fb_var_screeninfo *var;
400 	struct fb_info *info;
401 	struct offb_par *par;
402 
403 	if (!request_mem_region(res_start, res_size, "offb"))
404 		return;
405 
406 	printk(KERN_INFO
407 	       "Using unsupported %dx%d %s at %lx, depth=%d, pitch=%d\n",
408 	       width, height, name, address, depth, pitch);
409 	if (depth != 8 && depth != 15 && depth != 16 && depth != 32) {
410 		printk(KERN_ERR "%pOF: can't use depth = %d\n", dp, depth);
411 		release_mem_region(res_start, res_size);
412 		return;
413 	}
414 
415 	info = framebuffer_alloc(sizeof(*par), &parent->dev);
416 	if (!info) {
417 		release_mem_region(res_start, res_size);
418 		return;
419 	}
420 	platform_set_drvdata(parent, info);
421 	par = info->par;
422 	fix = &info->fix;
423 	var = &info->var;
424 
425 	if (name)
426 		snprintf(fix->id, sizeof(fix->id), "OFfb %s", name);
427 	else
428 		snprintf(fix->id, sizeof(fix->id), "OFfb %pOFn", dp);
429 
430 
431 	var->xres = var->xres_virtual = width;
432 	var->yres = var->yres_virtual = height;
433 	fix->line_length = pitch;
434 
435 	fix->smem_start = address;
436 	fix->smem_len = pitch * height;
437 	fix->type = FB_TYPE_PACKED_PIXELS;
438 	fix->type_aux = 0;
439 
440 	par->cmap_type = cmap_unknown;
441 	if (depth == 8)
442 		offb_init_palette_hacks(info, dp, address);
443 	else
444 		fix->visual = FB_VISUAL_TRUECOLOR;
445 
446 	var->xoffset = var->yoffset = 0;
447 	switch (depth) {
448 	case 8:
449 		var->bits_per_pixel = 8;
450 		var->red.offset = 0;
451 		var->red.length = 8;
452 		var->green.offset = 0;
453 		var->green.length = 8;
454 		var->blue.offset = 0;
455 		var->blue.length = 8;
456 		var->transp.offset = 0;
457 		var->transp.length = 0;
458 		break;
459 	case 15:		/* RGB 555 */
460 		var->bits_per_pixel = 16;
461 		var->red.offset = 10;
462 		var->red.length = 5;
463 		var->green.offset = 5;
464 		var->green.length = 5;
465 		var->blue.offset = 0;
466 		var->blue.length = 5;
467 		var->transp.offset = 0;
468 		var->transp.length = 0;
469 		break;
470 	case 16:		/* RGB 565 */
471 		var->bits_per_pixel = 16;
472 		var->red.offset = 11;
473 		var->red.length = 5;
474 		var->green.offset = 5;
475 		var->green.length = 6;
476 		var->blue.offset = 0;
477 		var->blue.length = 5;
478 		var->transp.offset = 0;
479 		var->transp.length = 0;
480 		break;
481 	case 32:		/* RGB 888 */
482 		var->bits_per_pixel = 32;
483 		var->red.offset = 16;
484 		var->red.length = 8;
485 		var->green.offset = 8;
486 		var->green.length = 8;
487 		var->blue.offset = 0;
488 		var->blue.length = 8;
489 		var->transp.offset = 24;
490 		var->transp.length = 8;
491 		break;
492 	}
493 	var->red.msb_right = var->green.msb_right = var->blue.msb_right =
494 	    var->transp.msb_right = 0;
495 	var->grayscale = 0;
496 	var->nonstd = 0;
497 	var->activate = 0;
498 	var->height = var->width = -1;
499 	var->pixclock = 10000;
500 	var->left_margin = var->right_margin = 16;
501 	var->upper_margin = var->lower_margin = 16;
502 	var->hsync_len = var->vsync_len = 8;
503 	var->sync = 0;
504 	var->vmode = FB_VMODE_NONINTERLACED;
505 
506 	par->base = address;
507 	par->size = fix->smem_len;
508 
509 	info->fbops = &offb_ops;
510 	info->screen_base = ioremap(address, fix->smem_len);
511 	info->pseudo_palette = par->pseudo_palette;
512 	info->flags = foreign_endian;
513 
514 	fb_alloc_cmap(&info->cmap, 256, 0);
515 
516 	if (devm_aperture_acquire_for_platform_device(parent, par->base, par->size) < 0)
517 		goto out_err;
518 	if (register_framebuffer(info) < 0)
519 		goto out_err;
520 
521 	fb_info(info, "Open Firmware frame buffer device on %pOF\n", dp);
522 	return;
523 
524 out_err:
525 	fb_dealloc_cmap(&info->cmap);
526 	iounmap(info->screen_base);
527 	iounmap(par->cmap_adr);
528 	par->cmap_adr = NULL;
529 	framebuffer_release(info);
530 	release_mem_region(res_start, res_size);
531 }
532 
533 
534 static void offb_init_nodriver(struct platform_device *parent, struct device_node *dp,
535 			       int no_real_node)
536 {
537 	unsigned int len;
538 	int i, width = 640, height = 480, depth = 8, pitch = 640;
539 	unsigned int flags, rsize, addr_prop = 0;
540 	unsigned long max_size = 0;
541 	u64 rstart, address = OF_BAD_ADDR;
542 	const __be32 *pp, *addrp, *up;
543 	u64 asize;
544 	int foreign_endian = 0;
545 
546 #ifdef __BIG_ENDIAN
547 	if (of_property_read_bool(dp, "little-endian"))
548 		foreign_endian = FBINFO_FOREIGN_ENDIAN;
549 #else
550 	if (of_property_read_bool(dp, "big-endian"))
551 		foreign_endian = FBINFO_FOREIGN_ENDIAN;
552 #endif
553 
554 	pp = of_get_property(dp, "linux,bootx-depth", &len);
555 	if (pp == NULL)
556 		pp = of_get_property(dp, "depth", &len);
557 	if (pp && len == sizeof(u32))
558 		depth = be32_to_cpup(pp);
559 
560 	pp = of_get_property(dp, "linux,bootx-width", &len);
561 	if (pp == NULL)
562 		pp = of_get_property(dp, "width", &len);
563 	if (pp && len == sizeof(u32))
564 		width = be32_to_cpup(pp);
565 
566 	pp = of_get_property(dp, "linux,bootx-height", &len);
567 	if (pp == NULL)
568 		pp = of_get_property(dp, "height", &len);
569 	if (pp && len == sizeof(u32))
570 		height = be32_to_cpup(pp);
571 
572 	pp = of_get_property(dp, "linux,bootx-linebytes", &len);
573 	if (pp == NULL)
574 		pp = of_get_property(dp, "linebytes", &len);
575 	if (pp && len == sizeof(u32) && (*pp != 0xffffffffu))
576 		pitch = be32_to_cpup(pp);
577 	else
578 		pitch = width * ((depth + 7) / 8);
579 
580 	rsize = (unsigned long)pitch * (unsigned long)height;
581 
582 	/* Ok, now we try to figure out the address of the framebuffer.
583 	 *
584 	 * Unfortunately, Open Firmware doesn't provide a standard way to do
585 	 * so. All we can do is a dodgy heuristic that happens to work in
586 	 * practice. On most machines, the "address" property contains what
587 	 * we need, though not on Matrox cards found in IBM machines. What I've
588 	 * found that appears to give good results is to go through the PCI
589 	 * ranges and pick one that is both big enough and if possible encloses
590 	 * the "address" property. If none match, we pick the biggest
591 	 */
592 	up = of_get_property(dp, "linux,bootx-addr", &len);
593 	if (up == NULL)
594 		up = of_get_property(dp, "address", &len);
595 	if (up && len == sizeof(u32))
596 		addr_prop = *up;
597 
598 	/* Hack for when BootX is passing us */
599 	if (no_real_node)
600 		goto skip_addr;
601 
602 	for (i = 0; (addrp = of_get_address(dp, i, &asize, &flags))
603 		     != NULL; i++) {
604 		int match_addrp = 0;
605 
606 		if (!(flags & IORESOURCE_MEM))
607 			continue;
608 		if (asize < rsize)
609 			continue;
610 		rstart = of_translate_address(dp, addrp);
611 		if (rstart == OF_BAD_ADDR)
612 			continue;
613 		if (addr_prop && (rstart <= addr_prop) &&
614 		    ((rstart + asize) >= (addr_prop + rsize)))
615 			match_addrp = 1;
616 		if (match_addrp) {
617 			address = addr_prop;
618 			break;
619 		}
620 		if (rsize > max_size) {
621 			max_size = rsize;
622 			address = OF_BAD_ADDR;
623  		}
624 
625 		if (address == OF_BAD_ADDR)
626 			address = rstart;
627 	}
628  skip_addr:
629 	if (address == OF_BAD_ADDR && addr_prop)
630 		address = (u64)addr_prop;
631 	if (address != OF_BAD_ADDR) {
632 #ifdef CONFIG_PCI
633 		const __be32 *vidp, *didp;
634 		u32 vid, did;
635 		struct pci_dev *pdev;
636 
637 		vidp = of_get_property(dp, "vendor-id", NULL);
638 		didp = of_get_property(dp, "device-id", NULL);
639 		if (vidp && didp) {
640 			vid = be32_to_cpup(vidp);
641 			did = be32_to_cpup(didp);
642 			pdev = pci_get_device(vid, did, NULL);
643 			if (!pdev || pci_enable_device(pdev))
644 				return;
645 		}
646 #endif
647 		/* kludge for valkyrie */
648 		if (of_node_name_eq(dp, "valkyrie"))
649 			address += 0x1000;
650 		offb_init_fb(parent, no_real_node ? "bootx" : NULL,
651 			     width, height, depth, pitch, address,
652 			     foreign_endian, no_real_node ? NULL : dp);
653 	}
654 }
655 
656 static void offb_remove(struct platform_device *pdev)
657 {
658 	struct fb_info *info = platform_get_drvdata(pdev);
659 
660 	if (info)
661 		unregister_framebuffer(info);
662 }
663 
664 static int offb_probe_bootx_noscreen(struct platform_device *pdev)
665 {
666 	offb_init_nodriver(pdev, of_chosen, 1);
667 
668 	return 0;
669 }
670 
671 static struct platform_driver offb_driver_bootx_noscreen = {
672 	.driver = {
673 		.name = "bootx-noscreen",
674 	},
675 	.probe = offb_probe_bootx_noscreen,
676 	.remove_new = offb_remove,
677 };
678 
679 static int offb_probe_display(struct platform_device *pdev)
680 {
681 	offb_init_nodriver(pdev, pdev->dev.of_node, 0);
682 
683 	return 0;
684 }
685 
686 static const struct of_device_id offb_of_match_display[] = {
687 	{ .compatible = "display", },
688 	{ },
689 };
690 MODULE_DEVICE_TABLE(of, offb_of_match_display);
691 
692 static struct platform_driver offb_driver_display = {
693 	.driver = {
694 		.name = "of-display",
695 		.of_match_table = offb_of_match_display,
696 	},
697 	.probe = offb_probe_display,
698 	.remove_new = offb_remove,
699 };
700 
701 static int __init offb_init(void)
702 {
703 	if (fb_get_options("offb", NULL))
704 		return -ENODEV;
705 
706 	platform_driver_register(&offb_driver_bootx_noscreen);
707 	platform_driver_register(&offb_driver_display);
708 
709 	return 0;
710 }
711 module_init(offb_init);
712 
713 static void __exit offb_exit(void)
714 {
715 	platform_driver_unregister(&offb_driver_display);
716 	platform_driver_unregister(&offb_driver_bootx_noscreen);
717 }
718 module_exit(offb_exit);
719 
720 MODULE_DESCRIPTION("Open Firmware frame buffer device driver");
721 MODULE_LICENSE("GPL");
722