xref: /openbmc/linux/drivers/video/fbdev/bw2.c (revision 6db6b729)
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_mmap(struct fb_info *, struct vm_area_struct *);
35 static int bw2_ioctl(struct fb_info *, unsigned int, unsigned long);
36 
37 /*
38  *  Frame buffer operations
39  */
40 
41 static const struct fb_ops bw2_ops = {
42 	.owner			= THIS_MODULE,
43 	.fb_blank		= bw2_blank,
44 	.fb_fillrect		= cfb_fillrect,
45 	.fb_copyarea		= cfb_copyarea,
46 	.fb_imageblit		= cfb_imageblit,
47 	.fb_mmap		= bw2_mmap,
48 	.fb_ioctl		= bw2_ioctl,
49 #ifdef CONFIG_COMPAT
50 	.fb_compat_ioctl	= sbusfb_compat_ioctl,
51 #endif
52 };
53 
54 /* OBio addresses for the bwtwo registers */
55 #define BWTWO_REGISTER_OFFSET 0x400000
56 
57 struct bt_regs {
58 	u32 addr;
59 	u32 color_map;
60 	u32 control;
61 	u32 cursor;
62 };
63 
64 struct bw2_regs {
65 	struct bt_regs	cmap;
66 	u8	control;
67 	u8	status;
68 	u8	cursor_start;
69 	u8	cursor_end;
70 	u8	h_blank_start;
71 	u8	h_blank_end;
72 	u8	h_sync_start;
73 	u8	h_sync_end;
74 	u8	comp_sync_end;
75 	u8	v_blank_start_high;
76 	u8	v_blank_start_low;
77 	u8	v_blank_end;
78 	u8	v_sync_start;
79 	u8	v_sync_end;
80 	u8	xfer_holdoff_start;
81 	u8	xfer_holdoff_end;
82 };
83 
84 /* Status Register Constants */
85 #define BWTWO_SR_RES_MASK	0x70
86 #define BWTWO_SR_1600_1280	0x50
87 #define BWTWO_SR_1152_900_76_A	0x40
88 #define BWTWO_SR_1152_900_76_B	0x60
89 #define BWTWO_SR_ID_MASK	0x0f
90 #define BWTWO_SR_ID_MONO	0x02
91 #define BWTWO_SR_ID_MONO_ECL	0x03
92 #define BWTWO_SR_ID_MSYNC	0x04
93 #define BWTWO_SR_ID_NOCONN	0x0a
94 
95 /* Control Register Constants */
96 #define BWTWO_CTL_ENABLE_INTS   0x80
97 #define BWTWO_CTL_ENABLE_VIDEO  0x40
98 #define BWTWO_CTL_ENABLE_TIMING 0x20
99 #define BWTWO_CTL_ENABLE_CURCMP 0x10
100 #define BWTWO_CTL_XTAL_MASK     0x0C
101 #define BWTWO_CTL_DIVISOR_MASK  0x03
102 
103 /* Status Register Constants */
104 #define BWTWO_STAT_PENDING_INT  0x80
105 #define BWTWO_STAT_MSENSE_MASK  0x70
106 #define BWTWO_STAT_ID_MASK      0x0f
107 
108 struct bw2_par {
109 	spinlock_t		lock;
110 	struct bw2_regs		__iomem *regs;
111 
112 	u32			flags;
113 #define BW2_FLAG_BLANKED	0x00000001
114 
115 	unsigned long		which_io;
116 };
117 
118 /**
119  *      bw2_blank - Optional function.  Blanks the display.
120  *      @blank: the blank mode we want.
121  *      @info: frame buffer structure that represents a single frame buffer
122  */
123 static int
124 bw2_blank(int blank, struct fb_info *info)
125 {
126 	struct bw2_par *par = (struct bw2_par *) info->par;
127 	struct bw2_regs __iomem *regs = par->regs;
128 	unsigned long flags;
129 	u8 val;
130 
131 	spin_lock_irqsave(&par->lock, flags);
132 
133 	switch (blank) {
134 	case FB_BLANK_UNBLANK: /* Unblanking */
135 		val = sbus_readb(&regs->control);
136 		val |= BWTWO_CTL_ENABLE_VIDEO;
137 		sbus_writeb(val, &regs->control);
138 		par->flags &= ~BW2_FLAG_BLANKED;
139 		break;
140 
141 	case FB_BLANK_NORMAL: /* Normal blanking */
142 	case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
143 	case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
144 	case FB_BLANK_POWERDOWN: /* Poweroff */
145 		val = sbus_readb(&regs->control);
146 		val &= ~BWTWO_CTL_ENABLE_VIDEO;
147 		sbus_writeb(val, &regs->control);
148 		par->flags |= BW2_FLAG_BLANKED;
149 		break;
150 	}
151 
152 	spin_unlock_irqrestore(&par->lock, flags);
153 
154 	return 0;
155 }
156 
157 static struct sbus_mmap_map bw2_mmap_map[] = {
158 	{
159 		.size = SBUS_MMAP_FBSIZE(1)
160 	},
161 	{ .size = 0 }
162 };
163 
164 static int bw2_mmap(struct fb_info *info, struct vm_area_struct *vma)
165 {
166 	struct bw2_par *par = (struct bw2_par *)info->par;
167 
168 	return sbusfb_mmap_helper(bw2_mmap_map,
169 				  info->fix.smem_start, info->fix.smem_len,
170 				  par->which_io,
171 				  vma);
172 }
173 
174 static int bw2_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
175 {
176 	return sbusfb_ioctl_helper(cmd, arg, info,
177 				   FBTYPE_SUN2BW, 1, info->fix.smem_len);
178 }
179 
180 /*
181  *  Initialisation
182  */
183 
184 static void bw2_init_fix(struct fb_info *info, int linebytes)
185 {
186 	strscpy(info->fix.id, "bwtwo", sizeof(info->fix.id));
187 
188 	info->fix.type = FB_TYPE_PACKED_PIXELS;
189 	info->fix.visual = FB_VISUAL_MONO01;
190 
191 	info->fix.line_length = linebytes;
192 
193 	info->fix.accel = FB_ACCEL_SUN_BWTWO;
194 }
195 
196 static u8 bw2regs_1600[] = {
197 	0x14, 0x8b,	0x15, 0x28,	0x16, 0x03,	0x17, 0x13,
198 	0x18, 0x7b,	0x19, 0x05,	0x1a, 0x34,	0x1b, 0x2e,
199 	0x1c, 0x00,	0x1d, 0x0a,	0x1e, 0xff,	0x1f, 0x01,
200 	0x10, 0x21,	0
201 };
202 
203 static u8 bw2regs_ecl[] = {
204 	0x14, 0x65,	0x15, 0x1e,	0x16, 0x04,	0x17, 0x0c,
205 	0x18, 0x5e,	0x19, 0x03,	0x1a, 0xa7,	0x1b, 0x23,
206 	0x1c, 0x00,	0x1d, 0x08,	0x1e, 0xff,	0x1f, 0x01,
207 	0x10, 0x20,	0
208 };
209 
210 static u8 bw2regs_analog[] = {
211 	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x03,	0x17, 0x13,
212 	0x18, 0xb0,	0x19, 0x03,	0x1a, 0xa6,	0x1b, 0x22,
213 	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
214 	0x10, 0x20,	0
215 };
216 
217 static u8 bw2regs_76hz[] = {
218 	0x14, 0xb7,	0x15, 0x27,	0x16, 0x03,	0x17, 0x0f,
219 	0x18, 0xae,	0x19, 0x03,	0x1a, 0xae,	0x1b, 0x2a,
220 	0x1c, 0x01,	0x1d, 0x09,	0x1e, 0xff,	0x1f, 0x01,
221 	0x10, 0x24,	0
222 };
223 
224 static u8 bw2regs_66hz[] = {
225 	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x04,	0x17, 0x14,
226 	0x18, 0xae,	0x19, 0x03,	0x1a, 0xa8,	0x1b, 0x24,
227 	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
228 	0x10, 0x20,	0
229 };
230 
231 static int bw2_do_default_mode(struct bw2_par *par, struct fb_info *info,
232 			       int *linebytes)
233 {
234 	u8 status, mon;
235 	u8 *p;
236 
237 	status = sbus_readb(&par->regs->status);
238 	mon = status & BWTWO_SR_RES_MASK;
239 	switch (status & BWTWO_SR_ID_MASK) {
240 	case BWTWO_SR_ID_MONO_ECL:
241 		if (mon == BWTWO_SR_1600_1280) {
242 			p = bw2regs_1600;
243 			info->var.xres = info->var.xres_virtual = 1600;
244 			info->var.yres = info->var.yres_virtual = 1280;
245 			*linebytes = 1600 / 8;
246 		} else
247 			p = bw2regs_ecl;
248 		break;
249 
250 	case BWTWO_SR_ID_MONO:
251 		p = bw2regs_analog;
252 		break;
253 
254 	case BWTWO_SR_ID_MSYNC:
255 		if (mon == BWTWO_SR_1152_900_76_A ||
256 		    mon == BWTWO_SR_1152_900_76_B)
257 			p = bw2regs_76hz;
258 		else
259 			p = bw2regs_66hz;
260 		break;
261 
262 	case BWTWO_SR_ID_NOCONN:
263 		return 0;
264 
265 	default:
266 		printk(KERN_ERR "bw2: can't handle SR %02x\n",
267 		       status);
268 		return -EINVAL;
269 	}
270 	for ( ; *p; p += 2) {
271 		u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
272 		sbus_writeb(p[1], regp);
273 	}
274 	return 0;
275 }
276 
277 static int bw2_probe(struct platform_device *op)
278 {
279 	struct device_node *dp = op->dev.of_node;
280 	struct fb_info *info;
281 	struct bw2_par *par;
282 	int linebytes, err;
283 
284 	info = framebuffer_alloc(sizeof(struct bw2_par), &op->dev);
285 
286 	err = -ENOMEM;
287 	if (!info)
288 		goto out_err;
289 	par = info->par;
290 
291 	spin_lock_init(&par->lock);
292 
293 	info->fix.smem_start = op->resource[0].start;
294 	par->which_io = op->resource[0].flags & IORESOURCE_BITS;
295 
296 	sbusfb_fill_var(&info->var, dp, 1);
297 	linebytes = of_getintprop_default(dp, "linebytes",
298 					  info->var.xres);
299 
300 	info->var.red.length = info->var.green.length =
301 		info->var.blue.length = info->var.bits_per_pixel;
302 	info->var.red.offset = info->var.green.offset =
303 		info->var.blue.offset = 0;
304 
305 	par->regs = of_ioremap(&op->resource[0], BWTWO_REGISTER_OFFSET,
306 			       sizeof(struct bw2_regs), "bw2 regs");
307 	if (!par->regs)
308 		goto out_release_fb;
309 
310 	if (!of_property_present(dp, "width")) {
311 		err = bw2_do_default_mode(par, info, &linebytes);
312 		if (err)
313 			goto out_unmap_regs;
314 	}
315 
316 	info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
317 
318 	info->fbops = &bw2_ops;
319 
320 	info->screen_base = of_ioremap(&op->resource[0], 0,
321 				       info->fix.smem_len, "bw2 ram");
322 	if (!info->screen_base) {
323 		err = -ENOMEM;
324 		goto out_unmap_regs;
325 	}
326 
327 	bw2_blank(FB_BLANK_UNBLANK, info);
328 
329 	bw2_init_fix(info, linebytes);
330 
331 	err = register_framebuffer(info);
332 	if (err < 0)
333 		goto out_unmap_screen;
334 
335 	dev_set_drvdata(&op->dev, info);
336 
337 	printk(KERN_INFO "%pOF: bwtwo at %lx:%lx\n",
338 	       dp, par->which_io, info->fix.smem_start);
339 
340 	return 0;
341 
342 out_unmap_screen:
343 	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
344 
345 out_unmap_regs:
346 	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
347 
348 out_release_fb:
349 	framebuffer_release(info);
350 
351 out_err:
352 	return err;
353 }
354 
355 static void bw2_remove(struct platform_device *op)
356 {
357 	struct fb_info *info = dev_get_drvdata(&op->dev);
358 	struct bw2_par *par = info->par;
359 
360 	unregister_framebuffer(info);
361 
362 	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
363 	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
364 
365 	framebuffer_release(info);
366 }
367 
368 static const struct of_device_id bw2_match[] = {
369 	{
370 		.name = "bwtwo",
371 	},
372 	{},
373 };
374 MODULE_DEVICE_TABLE(of, bw2_match);
375 
376 static struct platform_driver bw2_driver = {
377 	.driver = {
378 		.name = "bw2",
379 		.of_match_table = bw2_match,
380 	},
381 	.probe		= bw2_probe,
382 	.remove_new	= bw2_remove,
383 };
384 
385 static int __init bw2_init(void)
386 {
387 	if (fb_get_options("bw2fb", NULL))
388 		return -ENODEV;
389 
390 	return platform_driver_register(&bw2_driver);
391 }
392 
393 static void __exit bw2_exit(void)
394 {
395 	platform_driver_unregister(&bw2_driver);
396 }
397 
398 module_init(bw2_init);
399 module_exit(bw2_exit);
400 
401 MODULE_DESCRIPTION("framebuffer driver for BWTWO chipsets");
402 MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
403 MODULE_VERSION("2.0");
404 MODULE_LICENSE("GPL");
405