xref: /linux/drivers/video/fbdev/bw2.c (revision 7a92fc8b4d20680e4c20289a670d8fca2d1f2c1b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* bw2.c: BWTWO 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.h>
21 #include <linux/platform_device.h>
22 
23 #include <asm/io.h>
24 #include <asm/fbio.h>
25 
26 #include "sbuslib.h"
27 
28 /*
29  * Local functions.
30  */
31 
32 static int bw2_blank(int, struct fb_info *);
33 
34 static int bw2_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma);
35 static int bw2_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg);
36 
37 /*
38  *  Frame buffer operations
39  */
40 
41 static const struct fb_ops bw2_ops = {
42 	.owner			= THIS_MODULE,
43 	FB_DEFAULT_SBUS_OPS(bw2),
44 	.fb_blank		= bw2_blank,
45 };
46 
47 /* OBio addresses for the bwtwo registers */
48 #define BWTWO_REGISTER_OFFSET 0x400000
49 
50 struct bt_regs {
51 	u32 addr;
52 	u32 color_map;
53 	u32 control;
54 	u32 cursor;
55 };
56 
57 struct bw2_regs {
58 	struct bt_regs	cmap;
59 	u8	control;
60 	u8	status;
61 	u8	cursor_start;
62 	u8	cursor_end;
63 	u8	h_blank_start;
64 	u8	h_blank_end;
65 	u8	h_sync_start;
66 	u8	h_sync_end;
67 	u8	comp_sync_end;
68 	u8	v_blank_start_high;
69 	u8	v_blank_start_low;
70 	u8	v_blank_end;
71 	u8	v_sync_start;
72 	u8	v_sync_end;
73 	u8	xfer_holdoff_start;
74 	u8	xfer_holdoff_end;
75 };
76 
77 /* Status Register Constants */
78 #define BWTWO_SR_RES_MASK	0x70
79 #define BWTWO_SR_1600_1280	0x50
80 #define BWTWO_SR_1152_900_76_A	0x40
81 #define BWTWO_SR_1152_900_76_B	0x60
82 #define BWTWO_SR_ID_MASK	0x0f
83 #define BWTWO_SR_ID_MONO	0x02
84 #define BWTWO_SR_ID_MONO_ECL	0x03
85 #define BWTWO_SR_ID_MSYNC	0x04
86 #define BWTWO_SR_ID_NOCONN	0x0a
87 
88 /* Control Register Constants */
89 #define BWTWO_CTL_ENABLE_INTS   0x80
90 #define BWTWO_CTL_ENABLE_VIDEO  0x40
91 #define BWTWO_CTL_ENABLE_TIMING 0x20
92 #define BWTWO_CTL_ENABLE_CURCMP 0x10
93 #define BWTWO_CTL_XTAL_MASK     0x0C
94 #define BWTWO_CTL_DIVISOR_MASK  0x03
95 
96 /* Status Register Constants */
97 #define BWTWO_STAT_PENDING_INT  0x80
98 #define BWTWO_STAT_MSENSE_MASK  0x70
99 #define BWTWO_STAT_ID_MASK      0x0f
100 
101 struct bw2_par {
102 	spinlock_t		lock;
103 	struct bw2_regs		__iomem *regs;
104 
105 	u32			flags;
106 #define BW2_FLAG_BLANKED	0x00000001
107 
108 	unsigned long		which_io;
109 };
110 
111 /**
112  *      bw2_blank - Optional function.  Blanks the display.
113  *      @blank: the blank mode we want.
114  *      @info: frame buffer structure that represents a single frame buffer
115  */
116 static int
117 bw2_blank(int blank, struct fb_info *info)
118 {
119 	struct bw2_par *par = (struct bw2_par *) info->par;
120 	struct bw2_regs __iomem *regs = par->regs;
121 	unsigned long flags;
122 	u8 val;
123 
124 	spin_lock_irqsave(&par->lock, flags);
125 
126 	switch (blank) {
127 	case FB_BLANK_UNBLANK: /* Unblanking */
128 		val = sbus_readb(&regs->control);
129 		val |= BWTWO_CTL_ENABLE_VIDEO;
130 		sbus_writeb(val, &regs->control);
131 		par->flags &= ~BW2_FLAG_BLANKED;
132 		break;
133 
134 	case FB_BLANK_NORMAL: /* Normal blanking */
135 	case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
136 	case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
137 	case FB_BLANK_POWERDOWN: /* Poweroff */
138 		val = sbus_readb(&regs->control);
139 		val &= ~BWTWO_CTL_ENABLE_VIDEO;
140 		sbus_writeb(val, &regs->control);
141 		par->flags |= BW2_FLAG_BLANKED;
142 		break;
143 	}
144 
145 	spin_unlock_irqrestore(&par->lock, flags);
146 
147 	return 0;
148 }
149 
150 static struct sbus_mmap_map bw2_mmap_map[] = {
151 	{
152 		.size = SBUS_MMAP_FBSIZE(1)
153 	},
154 	{ .size = 0 }
155 };
156 
157 static int bw2_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
158 {
159 	struct bw2_par *par = (struct bw2_par *)info->par;
160 
161 	return sbusfb_mmap_helper(bw2_mmap_map,
162 				  info->fix.smem_start, info->fix.smem_len,
163 				  par->which_io,
164 				  vma);
165 }
166 
167 static int bw2_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
168 {
169 	return sbusfb_ioctl_helper(cmd, arg, info,
170 				   FBTYPE_SUN2BW, 1, info->fix.smem_len);
171 }
172 
173 /*
174  *  Initialisation
175  */
176 
177 static void bw2_init_fix(struct fb_info *info, int linebytes)
178 {
179 	strscpy(info->fix.id, "bwtwo", sizeof(info->fix.id));
180 
181 	info->fix.type = FB_TYPE_PACKED_PIXELS;
182 	info->fix.visual = FB_VISUAL_MONO01;
183 
184 	info->fix.line_length = linebytes;
185 
186 	info->fix.accel = FB_ACCEL_SUN_BWTWO;
187 }
188 
189 static u8 bw2regs_1600[] = {
190 	0x14, 0x8b,	0x15, 0x28,	0x16, 0x03,	0x17, 0x13,
191 	0x18, 0x7b,	0x19, 0x05,	0x1a, 0x34,	0x1b, 0x2e,
192 	0x1c, 0x00,	0x1d, 0x0a,	0x1e, 0xff,	0x1f, 0x01,
193 	0x10, 0x21,	0
194 };
195 
196 static u8 bw2regs_ecl[] = {
197 	0x14, 0x65,	0x15, 0x1e,	0x16, 0x04,	0x17, 0x0c,
198 	0x18, 0x5e,	0x19, 0x03,	0x1a, 0xa7,	0x1b, 0x23,
199 	0x1c, 0x00,	0x1d, 0x08,	0x1e, 0xff,	0x1f, 0x01,
200 	0x10, 0x20,	0
201 };
202 
203 static u8 bw2regs_analog[] = {
204 	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x03,	0x17, 0x13,
205 	0x18, 0xb0,	0x19, 0x03,	0x1a, 0xa6,	0x1b, 0x22,
206 	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
207 	0x10, 0x20,	0
208 };
209 
210 static u8 bw2regs_76hz[] = {
211 	0x14, 0xb7,	0x15, 0x27,	0x16, 0x03,	0x17, 0x0f,
212 	0x18, 0xae,	0x19, 0x03,	0x1a, 0xae,	0x1b, 0x2a,
213 	0x1c, 0x01,	0x1d, 0x09,	0x1e, 0xff,	0x1f, 0x01,
214 	0x10, 0x24,	0
215 };
216 
217 static u8 bw2regs_66hz[] = {
218 	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x04,	0x17, 0x14,
219 	0x18, 0xae,	0x19, 0x03,	0x1a, 0xa8,	0x1b, 0x24,
220 	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
221 	0x10, 0x20,	0
222 };
223 
224 static int bw2_do_default_mode(struct bw2_par *par, struct fb_info *info,
225 			       int *linebytes)
226 {
227 	u8 status, mon;
228 	u8 *p;
229 
230 	status = sbus_readb(&par->regs->status);
231 	mon = status & BWTWO_SR_RES_MASK;
232 	switch (status & BWTWO_SR_ID_MASK) {
233 	case BWTWO_SR_ID_MONO_ECL:
234 		if (mon == BWTWO_SR_1600_1280) {
235 			p = bw2regs_1600;
236 			info->var.xres = info->var.xres_virtual = 1600;
237 			info->var.yres = info->var.yres_virtual = 1280;
238 			*linebytes = 1600 / 8;
239 		} else
240 			p = bw2regs_ecl;
241 		break;
242 
243 	case BWTWO_SR_ID_MONO:
244 		p = bw2regs_analog;
245 		break;
246 
247 	case BWTWO_SR_ID_MSYNC:
248 		if (mon == BWTWO_SR_1152_900_76_A ||
249 		    mon == BWTWO_SR_1152_900_76_B)
250 			p = bw2regs_76hz;
251 		else
252 			p = bw2regs_66hz;
253 		break;
254 
255 	case BWTWO_SR_ID_NOCONN:
256 		return 0;
257 
258 	default:
259 		printk(KERN_ERR "bw2: can't handle SR %02x\n",
260 		       status);
261 		return -EINVAL;
262 	}
263 	for ( ; *p; p += 2) {
264 		u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
265 		sbus_writeb(p[1], regp);
266 	}
267 	return 0;
268 }
269 
270 static int bw2_probe(struct platform_device *op)
271 {
272 	struct device_node *dp = op->dev.of_node;
273 	struct fb_info *info;
274 	struct bw2_par *par;
275 	int linebytes, err;
276 
277 	info = framebuffer_alloc(sizeof(struct bw2_par), &op->dev);
278 
279 	err = -ENOMEM;
280 	if (!info)
281 		goto out_err;
282 	par = info->par;
283 
284 	spin_lock_init(&par->lock);
285 
286 	info->fix.smem_start = op->resource[0].start;
287 	par->which_io = op->resource[0].flags & IORESOURCE_BITS;
288 
289 	sbusfb_fill_var(&info->var, dp, 1);
290 	linebytes = of_getintprop_default(dp, "linebytes",
291 					  info->var.xres);
292 
293 	info->var.red.length = info->var.green.length =
294 		info->var.blue.length = info->var.bits_per_pixel;
295 	info->var.red.offset = info->var.green.offset =
296 		info->var.blue.offset = 0;
297 
298 	par->regs = of_ioremap(&op->resource[0], BWTWO_REGISTER_OFFSET,
299 			       sizeof(struct bw2_regs), "bw2 regs");
300 	if (!par->regs)
301 		goto out_release_fb;
302 
303 	if (!of_property_present(dp, "width")) {
304 		err = bw2_do_default_mode(par, info, &linebytes);
305 		if (err)
306 			goto out_unmap_regs;
307 	}
308 
309 	info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
310 
311 	info->fbops = &bw2_ops;
312 
313 	info->screen_base = of_ioremap(&op->resource[0], 0,
314 				       info->fix.smem_len, "bw2 ram");
315 	if (!info->screen_base) {
316 		err = -ENOMEM;
317 		goto out_unmap_regs;
318 	}
319 
320 	bw2_blank(FB_BLANK_UNBLANK, info);
321 
322 	bw2_init_fix(info, linebytes);
323 
324 	err = register_framebuffer(info);
325 	if (err < 0)
326 		goto out_unmap_screen;
327 
328 	dev_set_drvdata(&op->dev, info);
329 
330 	printk(KERN_INFO "%pOF: bwtwo at %lx:%lx\n",
331 	       dp, par->which_io, info->fix.smem_start);
332 
333 	return 0;
334 
335 out_unmap_screen:
336 	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
337 
338 out_unmap_regs:
339 	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
340 
341 out_release_fb:
342 	framebuffer_release(info);
343 
344 out_err:
345 	return err;
346 }
347 
348 static void bw2_remove(struct platform_device *op)
349 {
350 	struct fb_info *info = dev_get_drvdata(&op->dev);
351 	struct bw2_par *par = info->par;
352 
353 	unregister_framebuffer(info);
354 
355 	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
356 	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
357 
358 	framebuffer_release(info);
359 }
360 
361 static const struct of_device_id bw2_match[] = {
362 	{
363 		.name = "bwtwo",
364 	},
365 	{},
366 };
367 MODULE_DEVICE_TABLE(of, bw2_match);
368 
369 static struct platform_driver bw2_driver = {
370 	.driver = {
371 		.name = "bw2",
372 		.of_match_table = bw2_match,
373 	},
374 	.probe		= bw2_probe,
375 	.remove_new	= bw2_remove,
376 };
377 
378 static int __init bw2_init(void)
379 {
380 	if (fb_get_options("bw2fb", NULL))
381 		return -ENODEV;
382 
383 	return platform_driver_register(&bw2_driver);
384 }
385 
386 static void __exit bw2_exit(void)
387 {
388 	platform_driver_unregister(&bw2_driver);
389 }
390 
391 module_init(bw2_init);
392 module_exit(bw2_exit);
393 
394 MODULE_DESCRIPTION("framebuffer driver for BWTWO chipsets");
395 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
396 MODULE_VERSION("2.0");
397 MODULE_LICENSE("GPL");
398