xref: /openbmc/linux/drivers/video/fbdev/cg3.c (revision 2fa49589)
1 /* cg3.c: CGTHREE frame buffer driver
2  *
3  * Copyright (C) 2003, 2006 David S. Miller (davem@davemloft.net)
4  * Copyright (C) 1996,1998 Jakub Jelinek (jj@ultra.linux.cz)
5  * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
6  * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
7  *
8  * Driver layout based loosely on tgafb.c, see that file for credits.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/errno.h>
14 #include <linux/string.h>
15 #include <linux/delay.h>
16 #include <linux/init.h>
17 #include <linux/fb.h>
18 #include <linux/mm.h>
19 #include <linux/of_device.h>
20 
21 #include <asm/io.h>
22 #include <asm/fbio.h>
23 
24 #include "sbuslib.h"
25 
26 /*
27  * Local functions.
28  */
29 
30 static int cg3_setcolreg(unsigned, unsigned, unsigned, unsigned,
31 			 unsigned, struct fb_info *);
32 static int cg3_blank(int, struct fb_info *);
33 
34 static int cg3_mmap(struct fb_info *, struct vm_area_struct *);
35 static int cg3_ioctl(struct fb_info *, unsigned int, unsigned long);
36 
37 /*
38  *  Frame buffer operations
39  */
40 
41 static struct fb_ops cg3_ops = {
42 	.owner			= THIS_MODULE,
43 	.fb_setcolreg		= cg3_setcolreg,
44 	.fb_blank		= cg3_blank,
45 	.fb_fillrect		= cfb_fillrect,
46 	.fb_copyarea		= cfb_copyarea,
47 	.fb_imageblit		= cfb_imageblit,
48 	.fb_mmap		= cg3_mmap,
49 	.fb_ioctl		= cg3_ioctl,
50 #ifdef CONFIG_COMPAT
51 	.fb_compat_ioctl	= sbusfb_compat_ioctl,
52 #endif
53 };
54 
55 
56 /* Control Register Constants */
57 #define CG3_CR_ENABLE_INTS      0x80
58 #define CG3_CR_ENABLE_VIDEO     0x40
59 #define CG3_CR_ENABLE_TIMING    0x20
60 #define CG3_CR_ENABLE_CURCMP    0x10
61 #define CG3_CR_XTAL_MASK        0x0c
62 #define CG3_CR_DIVISOR_MASK     0x03
63 
64 /* Status Register Constants */
65 #define CG3_SR_PENDING_INT      0x80
66 #define CG3_SR_RES_MASK         0x70
67 #define CG3_SR_1152_900_76_A    0x40
68 #define CG3_SR_1152_900_76_B    0x60
69 #define CG3_SR_ID_MASK          0x0f
70 #define CG3_SR_ID_COLOR         0x01
71 #define CG3_SR_ID_MONO          0x02
72 #define CG3_SR_ID_MONO_ECL      0x03
73 
74 enum cg3_type {
75 	CG3_AT_66HZ = 0,
76 	CG3_AT_76HZ,
77 	CG3_RDI
78 };
79 
80 struct bt_regs {
81 	u32 addr;
82 	u32 color_map;
83 	u32 control;
84 	u32 cursor;
85 };
86 
87 struct cg3_regs {
88 	struct bt_regs	cmap;
89 	u8	control;
90 	u8	status;
91 	u8	cursor_start;
92 	u8	cursor_end;
93 	u8	h_blank_start;
94 	u8	h_blank_end;
95 	u8	h_sync_start;
96 	u8	h_sync_end;
97 	u8	comp_sync_end;
98 	u8	v_blank_start_high;
99 	u8	v_blank_start_low;
100 	u8	v_blank_end;
101 	u8	v_sync_start;
102 	u8	v_sync_end;
103 	u8	xfer_holdoff_start;
104 	u8	xfer_holdoff_end;
105 };
106 
107 /* Offset of interesting structures in the OBIO space */
108 #define CG3_REGS_OFFSET	     0x400000UL
109 #define CG3_RAM_OFFSET	     0x800000UL
110 
111 struct cg3_par {
112 	spinlock_t		lock;
113 	struct cg3_regs		__iomem *regs;
114 	u32			sw_cmap[((256 * 3) + 3) / 4];
115 
116 	u32			flags;
117 #define CG3_FLAG_BLANKED	0x00000001
118 #define CG3_FLAG_RDI		0x00000002
119 
120 	unsigned long		which_io;
121 };
122 
123 /**
124  *      cg3_setcolreg - Optional function. Sets a color register.
125  *      @regno: boolean, 0 copy local, 1 get_user() function
126  *      @red: frame buffer colormap structure
127  *      @green: The green value which can be up to 16 bits wide
128  *      @blue:  The blue value which can be up to 16 bits wide.
129  *      @transp: If supported the alpha value which can be up to 16 bits wide.
130  *      @info: frame buffer info structure
131  *
132  * The cg3 palette is loaded with 4 color values at each time
133  * so you end up with: (rgb)(r), (gb)(rg), (b)(rgb), and so on.
134  * We keep a sw copy of the hw cmap to assist us in this esoteric
135  * loading procedure.
136  */
137 static int cg3_setcolreg(unsigned regno,
138 			 unsigned red, unsigned green, unsigned blue,
139 			 unsigned transp, struct fb_info *info)
140 {
141 	struct cg3_par *par = (struct cg3_par *) info->par;
142 	struct bt_regs __iomem *bt = &par->regs->cmap;
143 	unsigned long flags;
144 	u32 *p32;
145 	u8 *p8;
146 	int count;
147 
148 	if (regno >= 256)
149 		return 1;
150 
151 	red >>= 8;
152 	green >>= 8;
153 	blue >>= 8;
154 
155 	spin_lock_irqsave(&par->lock, flags);
156 
157 	p8 = (u8 *)par->sw_cmap + (regno * 3);
158 	p8[0] = red;
159 	p8[1] = green;
160 	p8[2] = blue;
161 
162 #define D4M3(x) ((((x)>>2)<<1) + ((x)>>2))      /* (x/4)*3 */
163 #define D4M4(x) ((x)&~0x3)                      /* (x/4)*4 */
164 
165 	count = 3;
166 	p32 = &par->sw_cmap[D4M3(regno)];
167 	sbus_writel(D4M4(regno), &bt->addr);
168 	while (count--)
169 		sbus_writel(*p32++, &bt->color_map);
170 
171 #undef D4M3
172 #undef D4M4
173 
174 	spin_unlock_irqrestore(&par->lock, flags);
175 
176 	return 0;
177 }
178 
179 /**
180  *      cg3_blank - Optional function.  Blanks the display.
181  *      @blank_mode: the blank mode we want.
182  *      @info: frame buffer structure that represents a single frame buffer
183  */
184 static int cg3_blank(int blank, struct fb_info *info)
185 {
186 	struct cg3_par *par = (struct cg3_par *) info->par;
187 	struct cg3_regs __iomem *regs = par->regs;
188 	unsigned long flags;
189 	u8 val;
190 
191 	spin_lock_irqsave(&par->lock, flags);
192 
193 	switch (blank) {
194 	case FB_BLANK_UNBLANK: /* Unblanking */
195 		val = sbus_readb(&regs->control);
196 		val |= CG3_CR_ENABLE_VIDEO;
197 		sbus_writeb(val, &regs->control);
198 		par->flags &= ~CG3_FLAG_BLANKED;
199 		break;
200 
201 	case FB_BLANK_NORMAL: /* Normal blanking */
202 	case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
203 	case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
204 	case FB_BLANK_POWERDOWN: /* Poweroff */
205 		val = sbus_readb(&regs->control);
206 		val &= ~CG3_CR_ENABLE_VIDEO;
207 		sbus_writeb(val, &regs->control);
208 		par->flags |= CG3_FLAG_BLANKED;
209 		break;
210 	}
211 
212 	spin_unlock_irqrestore(&par->lock, flags);
213 
214 	return 0;
215 }
216 
217 static struct sbus_mmap_map cg3_mmap_map[] = {
218 	{
219 		.voff	= CG3_MMAP_OFFSET,
220 		.poff	= CG3_RAM_OFFSET,
221 		.size	= SBUS_MMAP_FBSIZE(1)
222 	},
223 	{ .size = 0 }
224 };
225 
226 static int cg3_mmap(struct fb_info *info, struct vm_area_struct *vma)
227 {
228 	struct cg3_par *par = (struct cg3_par *)info->par;
229 
230 	return sbusfb_mmap_helper(cg3_mmap_map,
231 				  info->fix.smem_start, info->fix.smem_len,
232 				  par->which_io,
233 				  vma);
234 }
235 
236 static int cg3_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
237 {
238 	return sbusfb_ioctl_helper(cmd, arg, info,
239 				   FBTYPE_SUN3COLOR, 8, info->fix.smem_len);
240 }
241 
242 /*
243  *  Initialisation
244  */
245 
246 static void cg3_init_fix(struct fb_info *info, int linebytes,
247 			 struct device_node *dp)
248 {
249 	snprintf(info->fix.id, sizeof(info->fix.id), "%pOFn", dp);
250 
251 	info->fix.type = FB_TYPE_PACKED_PIXELS;
252 	info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
253 
254 	info->fix.line_length = linebytes;
255 
256 	info->fix.accel = FB_ACCEL_SUN_CGTHREE;
257 }
258 
259 static void cg3_rdi_maybe_fixup_var(struct fb_var_screeninfo *var,
260 				    struct device_node *dp)
261 {
262 	const char *params;
263 	char *p;
264 	int ww, hh;
265 
266 	params = of_get_property(dp, "params", NULL);
267 	if (params) {
268 		ww = simple_strtoul(params, &p, 10);
269 		if (ww && *p == 'x') {
270 			hh = simple_strtoul(p + 1, &p, 10);
271 			if (hh && *p == '-') {
272 				if (var->xres != ww ||
273 				    var->yres != hh) {
274 					var->xres = var->xres_virtual = ww;
275 					var->yres = var->yres_virtual = hh;
276 				}
277 			}
278 		}
279 	}
280 }
281 
282 static u8 cg3regvals_66hz[] = {	/* 1152 x 900, 66 Hz */
283 	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x04,	0x17, 0x14,
284 	0x18, 0xae,	0x19, 0x03,	0x1a, 0xa8,	0x1b, 0x24,
285 	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
286 	0x10, 0x20,	0
287 };
288 
289 static u8 cg3regvals_76hz[] = {	/* 1152 x 900, 76 Hz */
290 	0x14, 0xb7,	0x15, 0x27,	0x16, 0x03,	0x17, 0x0f,
291 	0x18, 0xae,	0x19, 0x03,	0x1a, 0xae,	0x1b, 0x2a,
292 	0x1c, 0x01,	0x1d, 0x09,	0x1e, 0xff,	0x1f, 0x01,
293 	0x10, 0x24,	0
294 };
295 
296 static u8 cg3regvals_rdi[] = {	/* 640 x 480, cgRDI */
297 	0x14, 0x70,	0x15, 0x20,	0x16, 0x08,	0x17, 0x10,
298 	0x18, 0x06,	0x19, 0x02,	0x1a, 0x31,	0x1b, 0x51,
299 	0x1c, 0x06,	0x1d, 0x0c,	0x1e, 0xff,	0x1f, 0x01,
300 	0x10, 0x22,	0
301 };
302 
303 static u8 *cg3_regvals[] = {
304 	cg3regvals_66hz, cg3regvals_76hz, cg3regvals_rdi
305 };
306 
307 static u_char cg3_dacvals[] = {
308 	4, 0xff,	5, 0x00,	6, 0x70,	7, 0x00,	0
309 };
310 
311 static int cg3_do_default_mode(struct cg3_par *par)
312 {
313 	enum cg3_type type;
314 	u8 *p;
315 
316 	if (par->flags & CG3_FLAG_RDI)
317 		type = CG3_RDI;
318 	else {
319 		u8 status = sbus_readb(&par->regs->status), mon;
320 		if ((status & CG3_SR_ID_MASK) == CG3_SR_ID_COLOR) {
321 			mon = status & CG3_SR_RES_MASK;
322 			if (mon == CG3_SR_1152_900_76_A ||
323 			    mon == CG3_SR_1152_900_76_B)
324 				type = CG3_AT_76HZ;
325 			else
326 				type = CG3_AT_66HZ;
327 		} else {
328 			printk(KERN_ERR "cgthree: can't handle SR %02x\n",
329 			       status);
330 			return -EINVAL;
331 		}
332 	}
333 
334 	for (p = cg3_regvals[type]; *p; p += 2) {
335 		u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
336 		sbus_writeb(p[1], regp);
337 	}
338 	for (p = cg3_dacvals; *p; p += 2) {
339 		u8 __iomem *regp;
340 
341 		regp = (u8 __iomem *)&par->regs->cmap.addr;
342 		sbus_writeb(p[0], regp);
343 		regp = (u8 __iomem *)&par->regs->cmap.control;
344 		sbus_writeb(p[1], regp);
345 	}
346 	return 0;
347 }
348 
349 static int cg3_probe(struct platform_device *op)
350 {
351 	struct device_node *dp = op->dev.of_node;
352 	struct fb_info *info;
353 	struct cg3_par *par;
354 	int linebytes, err;
355 
356 	info = framebuffer_alloc(sizeof(struct cg3_par), &op->dev);
357 
358 	err = -ENOMEM;
359 	if (!info)
360 		goto out_err;
361 	par = info->par;
362 
363 	spin_lock_init(&par->lock);
364 
365 	info->fix.smem_start = op->resource[0].start;
366 	par->which_io = op->resource[0].flags & IORESOURCE_BITS;
367 
368 	sbusfb_fill_var(&info->var, dp, 8);
369 	info->var.red.length = 8;
370 	info->var.green.length = 8;
371 	info->var.blue.length = 8;
372 	if (!strcmp(dp->name, "cgRDI"))
373 		par->flags |= CG3_FLAG_RDI;
374 	if (par->flags & CG3_FLAG_RDI)
375 		cg3_rdi_maybe_fixup_var(&info->var, dp);
376 
377 	linebytes = of_getintprop_default(dp, "linebytes",
378 					  info->var.xres);
379 	info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
380 
381 	par->regs = of_ioremap(&op->resource[0], CG3_REGS_OFFSET,
382 			       sizeof(struct cg3_regs), "cg3 regs");
383 	if (!par->regs)
384 		goto out_release_fb;
385 
386 	info->flags = FBINFO_DEFAULT;
387 	info->fbops = &cg3_ops;
388 	info->screen_base = of_ioremap(&op->resource[0], CG3_RAM_OFFSET,
389 				       info->fix.smem_len, "cg3 ram");
390 	if (!info->screen_base)
391 		goto out_unmap_regs;
392 
393 	cg3_blank(FB_BLANK_UNBLANK, info);
394 
395 	if (!of_find_property(dp, "width", NULL)) {
396 		err = cg3_do_default_mode(par);
397 		if (err)
398 			goto out_unmap_screen;
399 	}
400 
401 	err = fb_alloc_cmap(&info->cmap, 256, 0);
402 	if (err)
403 		goto out_unmap_screen;
404 
405 	fb_set_cmap(&info->cmap, info);
406 
407 	cg3_init_fix(info, linebytes, dp);
408 
409 	err = register_framebuffer(info);
410 	if (err < 0)
411 		goto out_dealloc_cmap;
412 
413 	dev_set_drvdata(&op->dev, info);
414 
415 	printk(KERN_INFO "%pOF: cg3 at %lx:%lx\n",
416 	       dp, par->which_io, info->fix.smem_start);
417 
418 	return 0;
419 
420 out_dealloc_cmap:
421 	fb_dealloc_cmap(&info->cmap);
422 
423 out_unmap_screen:
424 	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
425 
426 out_unmap_regs:
427 	of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
428 
429 out_release_fb:
430 	framebuffer_release(info);
431 
432 out_err:
433 	return err;
434 }
435 
436 static int cg3_remove(struct platform_device *op)
437 {
438 	struct fb_info *info = dev_get_drvdata(&op->dev);
439 	struct cg3_par *par = info->par;
440 
441 	unregister_framebuffer(info);
442 	fb_dealloc_cmap(&info->cmap);
443 
444 	of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
445 	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
446 
447 	framebuffer_release(info);
448 
449 	return 0;
450 }
451 
452 static const struct of_device_id cg3_match[] = {
453 	{
454 		.name = "cgthree",
455 	},
456 	{
457 		.name = "cgRDI",
458 	},
459 	{},
460 };
461 MODULE_DEVICE_TABLE(of, cg3_match);
462 
463 static struct platform_driver cg3_driver = {
464 	.driver = {
465 		.name = "cg3",
466 		.of_match_table = cg3_match,
467 	},
468 	.probe		= cg3_probe,
469 	.remove		= cg3_remove,
470 };
471 
472 static int __init cg3_init(void)
473 {
474 	if (fb_get_options("cg3fb", NULL))
475 		return -ENODEV;
476 
477 	return platform_driver_register(&cg3_driver);
478 }
479 
480 static void __exit cg3_exit(void)
481 {
482 	platform_driver_unregister(&cg3_driver);
483 }
484 
485 module_init(cg3_init);
486 module_exit(cg3_exit);
487 
488 MODULE_DESCRIPTION("framebuffer driver for CGthree chipsets");
489 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
490 MODULE_VERSION("2.0");
491 MODULE_LICENSE("GPL");
492