1 // SPDX-License-Identifier: GPL-2.0-only
2 /* cg3.c: CGTHREE frame buffer driver
3 *
4 * Copyright (C) 2003, 2006 David S. Miller (davem@davemloft.net)
5 * Copyright (C) 1996,1998 Jakub Jelinek (jj@ultra.linux.cz)
6 * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
7 * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
8 *
9 * Driver layout based loosely on tgafb.c, see that file for credits.
10 */
11
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/errno.h>
15 #include <linux/string.h>
16 #include <linux/delay.h>
17 #include <linux/init.h>
18 #include <linux/fb.h>
19 #include <linux/mm.h>
20 #include <linux/of_device.h>
21
22 #include <asm/io.h>
23 #include <asm/fbio.h>
24
25 #include "sbuslib.h"
26
27 /*
28 * Local functions.
29 */
30
31 static int cg3_setcolreg(unsigned, unsigned, unsigned, unsigned,
32 unsigned, struct fb_info *);
33 static int cg3_blank(int, struct fb_info *);
34
35 static int cg3_mmap(struct fb_info *, struct vm_area_struct *);
36 static int cg3_ioctl(struct fb_info *, unsigned int, unsigned long);
37
38 /*
39 * Frame buffer operations
40 */
41
42 static const struct fb_ops cg3_ops = {
43 .owner = THIS_MODULE,
44 .fb_setcolreg = cg3_setcolreg,
45 .fb_blank = cg3_blank,
46 .fb_fillrect = cfb_fillrect,
47 .fb_copyarea = cfb_copyarea,
48 .fb_imageblit = cfb_imageblit,
49 .fb_mmap = cg3_mmap,
50 .fb_ioctl = cg3_ioctl,
51 #ifdef CONFIG_COMPAT
52 .fb_compat_ioctl = sbusfb_compat_ioctl,
53 #endif
54 };
55
56
57 /* Control Register Constants */
58 #define CG3_CR_ENABLE_INTS 0x80
59 #define CG3_CR_ENABLE_VIDEO 0x40
60 #define CG3_CR_ENABLE_TIMING 0x20
61 #define CG3_CR_ENABLE_CURCMP 0x10
62 #define CG3_CR_XTAL_MASK 0x0c
63 #define CG3_CR_DIVISOR_MASK 0x03
64
65 /* Status Register Constants */
66 #define CG3_SR_PENDING_INT 0x80
67 #define CG3_SR_RES_MASK 0x70
68 #define CG3_SR_1152_900_76_A 0x40
69 #define CG3_SR_1152_900_76_B 0x60
70 #define CG3_SR_ID_MASK 0x0f
71 #define CG3_SR_ID_COLOR 0x01
72 #define CG3_SR_ID_MONO 0x02
73 #define CG3_SR_ID_MONO_ECL 0x03
74
75 enum cg3_type {
76 CG3_AT_66HZ = 0,
77 CG3_AT_76HZ,
78 CG3_RDI
79 };
80
81 struct bt_regs {
82 u32 addr;
83 u32 color_map;
84 u32 control;
85 u32 cursor;
86 };
87
88 struct cg3_regs {
89 struct bt_regs cmap;
90 u8 control;
91 u8 status;
92 u8 cursor_start;
93 u8 cursor_end;
94 u8 h_blank_start;
95 u8 h_blank_end;
96 u8 h_sync_start;
97 u8 h_sync_end;
98 u8 comp_sync_end;
99 u8 v_blank_start_high;
100 u8 v_blank_start_low;
101 u8 v_blank_end;
102 u8 v_sync_start;
103 u8 v_sync_end;
104 u8 xfer_holdoff_start;
105 u8 xfer_holdoff_end;
106 };
107
108 /* Offset of interesting structures in the OBIO space */
109 #define CG3_REGS_OFFSET 0x400000UL
110 #define CG3_RAM_OFFSET 0x800000UL
111
112 struct cg3_par {
113 spinlock_t lock;
114 struct cg3_regs __iomem *regs;
115 u32 sw_cmap[((256 * 3) + 3) / 4];
116
117 u32 flags;
118 #define CG3_FLAG_BLANKED 0x00000001
119 #define CG3_FLAG_RDI 0x00000002
120
121 unsigned long which_io;
122 };
123
124 /**
125 * cg3_setcolreg - Optional function. Sets a color register.
126 * @regno: boolean, 0 copy local, 1 get_user() function
127 * @red: frame buffer colormap structure
128 * @green: The green value which can be up to 16 bits wide
129 * @blue: The blue value which can be up to 16 bits wide.
130 * @transp: If supported the alpha value which can be up to 16 bits wide.
131 * @info: frame buffer info structure
132 *
133 * The cg3 palette is loaded with 4 color values at each time
134 * so you end up with: (rgb)(r), (gb)(rg), (b)(rgb), and so on.
135 * We keep a sw copy of the hw cmap to assist us in this esoteric
136 * loading procedure.
137 */
cg3_setcolreg(unsigned regno,unsigned red,unsigned green,unsigned blue,unsigned transp,struct fb_info * info)138 static int cg3_setcolreg(unsigned regno,
139 unsigned red, unsigned green, unsigned blue,
140 unsigned transp, struct fb_info *info)
141 {
142 struct cg3_par *par = (struct cg3_par *) info->par;
143 struct bt_regs __iomem *bt = &par->regs->cmap;
144 unsigned long flags;
145 u32 *p32;
146 u8 *p8;
147 int count;
148
149 if (regno >= 256)
150 return 1;
151
152 red >>= 8;
153 green >>= 8;
154 blue >>= 8;
155
156 spin_lock_irqsave(&par->lock, flags);
157
158 p8 = (u8 *)par->sw_cmap + (regno * 3);
159 p8[0] = red;
160 p8[1] = green;
161 p8[2] = blue;
162
163 #define D4M3(x) ((((x)>>2)<<1) + ((x)>>2)) /* (x/4)*3 */
164 #define D4M4(x) ((x)&~0x3) /* (x/4)*4 */
165
166 count = 3;
167 p32 = &par->sw_cmap[D4M3(regno)];
168 sbus_writel(D4M4(regno), &bt->addr);
169 while (count--)
170 sbus_writel(*p32++, &bt->color_map);
171
172 #undef D4M3
173 #undef D4M4
174
175 spin_unlock_irqrestore(&par->lock, flags);
176
177 return 0;
178 }
179
180 /**
181 * cg3_blank - Optional function. Blanks the display.
182 * @blank_mode: the blank mode we want.
183 * @info: frame buffer structure that represents a single frame buffer
184 */
cg3_blank(int blank,struct fb_info * info)185 static int cg3_blank(int blank, struct fb_info *info)
186 {
187 struct cg3_par *par = (struct cg3_par *) info->par;
188 struct cg3_regs __iomem *regs = par->regs;
189 unsigned long flags;
190 u8 val;
191
192 spin_lock_irqsave(&par->lock, flags);
193
194 switch (blank) {
195 case FB_BLANK_UNBLANK: /* Unblanking */
196 val = sbus_readb(®s->control);
197 val |= CG3_CR_ENABLE_VIDEO;
198 sbus_writeb(val, ®s->control);
199 par->flags &= ~CG3_FLAG_BLANKED;
200 break;
201
202 case FB_BLANK_NORMAL: /* Normal blanking */
203 case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
204 case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
205 case FB_BLANK_POWERDOWN: /* Poweroff */
206 val = sbus_readb(®s->control);
207 val &= ~CG3_CR_ENABLE_VIDEO;
208 sbus_writeb(val, ®s->control);
209 par->flags |= CG3_FLAG_BLANKED;
210 break;
211 }
212
213 spin_unlock_irqrestore(&par->lock, flags);
214
215 return 0;
216 }
217
218 static struct sbus_mmap_map cg3_mmap_map[] = {
219 {
220 .voff = CG3_MMAP_OFFSET,
221 .poff = CG3_RAM_OFFSET,
222 .size = SBUS_MMAP_FBSIZE(1)
223 },
224 { .size = 0 }
225 };
226
cg3_mmap(struct fb_info * info,struct vm_area_struct * vma)227 static int cg3_mmap(struct fb_info *info, struct vm_area_struct *vma)
228 {
229 struct cg3_par *par = (struct cg3_par *)info->par;
230
231 return sbusfb_mmap_helper(cg3_mmap_map,
232 info->fix.smem_start, info->fix.smem_len,
233 par->which_io,
234 vma);
235 }
236
cg3_ioctl(struct fb_info * info,unsigned int cmd,unsigned long arg)237 static int cg3_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
238 {
239 return sbusfb_ioctl_helper(cmd, arg, info,
240 FBTYPE_SUN3COLOR, 8, info->fix.smem_len);
241 }
242
243 /*
244 * Initialisation
245 */
246
cg3_init_fix(struct fb_info * info,int linebytes,struct device_node * dp)247 static void cg3_init_fix(struct fb_info *info, int linebytes,
248 struct device_node *dp)
249 {
250 snprintf(info->fix.id, sizeof(info->fix.id), "%pOFn", dp);
251
252 info->fix.type = FB_TYPE_PACKED_PIXELS;
253 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
254
255 info->fix.line_length = linebytes;
256
257 info->fix.accel = FB_ACCEL_SUN_CGTHREE;
258 }
259
cg3_rdi_maybe_fixup_var(struct fb_var_screeninfo * var,struct device_node * dp)260 static void cg3_rdi_maybe_fixup_var(struct fb_var_screeninfo *var,
261 struct device_node *dp)
262 {
263 const char *params;
264 char *p;
265 int ww, hh;
266
267 params = of_get_property(dp, "params", NULL);
268 if (params) {
269 ww = simple_strtoul(params, &p, 10);
270 if (ww && *p == 'x') {
271 hh = simple_strtoul(p + 1, &p, 10);
272 if (hh && *p == '-') {
273 if (var->xres != ww ||
274 var->yres != hh) {
275 var->xres = var->xres_virtual = ww;
276 var->yres = var->yres_virtual = hh;
277 }
278 }
279 }
280 }
281 }
282
283 static u8 cg3regvals_66hz[] = { /* 1152 x 900, 66 Hz */
284 0x14, 0xbb, 0x15, 0x2b, 0x16, 0x04, 0x17, 0x14,
285 0x18, 0xae, 0x19, 0x03, 0x1a, 0xa8, 0x1b, 0x24,
286 0x1c, 0x01, 0x1d, 0x05, 0x1e, 0xff, 0x1f, 0x01,
287 0x10, 0x20, 0
288 };
289
290 static u8 cg3regvals_76hz[] = { /* 1152 x 900, 76 Hz */
291 0x14, 0xb7, 0x15, 0x27, 0x16, 0x03, 0x17, 0x0f,
292 0x18, 0xae, 0x19, 0x03, 0x1a, 0xae, 0x1b, 0x2a,
293 0x1c, 0x01, 0x1d, 0x09, 0x1e, 0xff, 0x1f, 0x01,
294 0x10, 0x24, 0
295 };
296
297 static u8 cg3regvals_rdi[] = { /* 640 x 480, cgRDI */
298 0x14, 0x70, 0x15, 0x20, 0x16, 0x08, 0x17, 0x10,
299 0x18, 0x06, 0x19, 0x02, 0x1a, 0x31, 0x1b, 0x51,
300 0x1c, 0x06, 0x1d, 0x0c, 0x1e, 0xff, 0x1f, 0x01,
301 0x10, 0x22, 0
302 };
303
304 static u8 *cg3_regvals[] = {
305 cg3regvals_66hz, cg3regvals_76hz, cg3regvals_rdi
306 };
307
308 static u_char cg3_dacvals[] = {
309 4, 0xff, 5, 0x00, 6, 0x70, 7, 0x00, 0
310 };
311
cg3_do_default_mode(struct cg3_par * par)312 static int cg3_do_default_mode(struct cg3_par *par)
313 {
314 enum cg3_type type;
315 u8 *p;
316
317 if (par->flags & CG3_FLAG_RDI)
318 type = CG3_RDI;
319 else {
320 u8 status = sbus_readb(&par->regs->status), mon;
321 if ((status & CG3_SR_ID_MASK) == CG3_SR_ID_COLOR) {
322 mon = status & CG3_SR_RES_MASK;
323 if (mon == CG3_SR_1152_900_76_A ||
324 mon == CG3_SR_1152_900_76_B)
325 type = CG3_AT_76HZ;
326 else
327 type = CG3_AT_66HZ;
328 } else {
329 printk(KERN_ERR "cgthree: can't handle SR %02x\n",
330 status);
331 return -EINVAL;
332 }
333 }
334
335 for (p = cg3_regvals[type]; *p; p += 2) {
336 u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
337 sbus_writeb(p[1], regp);
338 }
339 for (p = cg3_dacvals; *p; p += 2) {
340 u8 __iomem *regp;
341
342 regp = (u8 __iomem *)&par->regs->cmap.addr;
343 sbus_writeb(p[0], regp);
344 regp = (u8 __iomem *)&par->regs->cmap.control;
345 sbus_writeb(p[1], regp);
346 }
347 return 0;
348 }
349
cg3_probe(struct platform_device * op)350 static int cg3_probe(struct platform_device *op)
351 {
352 struct device_node *dp = op->dev.of_node;
353 struct fb_info *info;
354 struct cg3_par *par;
355 int linebytes, err;
356
357 info = framebuffer_alloc(sizeof(struct cg3_par), &op->dev);
358
359 err = -ENOMEM;
360 if (!info)
361 goto out_err;
362 par = info->par;
363
364 spin_lock_init(&par->lock);
365
366 info->fix.smem_start = op->resource[0].start;
367 par->which_io = op->resource[0].flags & IORESOURCE_BITS;
368
369 sbusfb_fill_var(&info->var, dp, 8);
370 info->var.red.length = 8;
371 info->var.green.length = 8;
372 info->var.blue.length = 8;
373 if (of_node_name_eq(dp, "cgRDI"))
374 par->flags |= CG3_FLAG_RDI;
375 if (par->flags & CG3_FLAG_RDI)
376 cg3_rdi_maybe_fixup_var(&info->var, dp);
377
378 linebytes = of_getintprop_default(dp, "linebytes",
379 info->var.xres);
380 info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
381
382 par->regs = of_ioremap(&op->resource[0], CG3_REGS_OFFSET,
383 sizeof(struct cg3_regs), "cg3 regs");
384 if (!par->regs)
385 goto out_release_fb;
386
387 info->flags = FBINFO_DEFAULT;
388 info->fbops = &cg3_ops;
389 info->screen_base = of_ioremap(&op->resource[0], CG3_RAM_OFFSET,
390 info->fix.smem_len, "cg3 ram");
391 if (!info->screen_base)
392 goto out_unmap_regs;
393
394 cg3_blank(FB_BLANK_UNBLANK, info);
395
396 if (!of_find_property(dp, "width", NULL)) {
397 err = cg3_do_default_mode(par);
398 if (err)
399 goto out_unmap_screen;
400 }
401
402 err = fb_alloc_cmap(&info->cmap, 256, 0);
403 if (err)
404 goto out_unmap_screen;
405
406 fb_set_cmap(&info->cmap, info);
407
408 cg3_init_fix(info, linebytes, dp);
409
410 err = register_framebuffer(info);
411 if (err < 0)
412 goto out_dealloc_cmap;
413
414 dev_set_drvdata(&op->dev, info);
415
416 printk(KERN_INFO "%pOF: cg3 at %lx:%lx\n",
417 dp, par->which_io, info->fix.smem_start);
418
419 return 0;
420
421 out_dealloc_cmap:
422 fb_dealloc_cmap(&info->cmap);
423
424 out_unmap_screen:
425 of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
426
427 out_unmap_regs:
428 of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
429
430 out_release_fb:
431 framebuffer_release(info);
432
433 out_err:
434 return err;
435 }
436
cg3_remove(struct platform_device * op)437 static int cg3_remove(struct platform_device *op)
438 {
439 struct fb_info *info = dev_get_drvdata(&op->dev);
440 struct cg3_par *par = info->par;
441
442 unregister_framebuffer(info);
443 fb_dealloc_cmap(&info->cmap);
444
445 of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
446 of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
447
448 framebuffer_release(info);
449
450 return 0;
451 }
452
453 static const struct of_device_id cg3_match[] = {
454 {
455 .name = "cgthree",
456 },
457 {
458 .name = "cgRDI",
459 },
460 {},
461 };
462 MODULE_DEVICE_TABLE(of, cg3_match);
463
464 static struct platform_driver cg3_driver = {
465 .driver = {
466 .name = "cg3",
467 .of_match_table = cg3_match,
468 },
469 .probe = cg3_probe,
470 .remove = cg3_remove,
471 };
472
cg3_init(void)473 static int __init cg3_init(void)
474 {
475 if (fb_get_options("cg3fb", NULL))
476 return -ENODEV;
477
478 return platform_driver_register(&cg3_driver);
479 }
480
cg3_exit(void)481 static void __exit cg3_exit(void)
482 {
483 platform_driver_unregister(&cg3_driver);
484 }
485
486 module_init(cg3_init);
487 module_exit(cg3_exit);
488
489 MODULE_DESCRIPTION("framebuffer driver for CGthree chipsets");
490 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
491 MODULE_VERSION("2.0");
492 MODULE_LICENSE("GPL");
493