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
32static int bw2_blank(int, struct fb_info *);
33
34static int bw2_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma);
35static int bw2_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg);
36
37/*
38 *  Frame buffer operations
39 */
40
41static 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
50struct bt_regs {
51	u32 addr;
52	u32 color_map;
53	u32 control;
54	u32 cursor;
55};
56
57struct 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
101struct 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 */
116static int
117bw2_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
150static struct sbus_mmap_map bw2_mmap_map[] = {
151	{
152		.size = SBUS_MMAP_FBSIZE(1)
153	},
154	{ .size = 0 }
155};
156
157static 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
167static 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
177static 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
189static 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
196static 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
203static 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
210static 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
217static 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
224static 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
270static 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
335out_unmap_screen:
336	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
337
338out_unmap_regs:
339	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
340
341out_release_fb:
342	framebuffer_release(info);
343
344out_err:
345	return err;
346}
347
348static 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
361static const struct of_device_id bw2_match[] = {
362	{
363		.name = "bwtwo",
364	},
365	{},
366};
367MODULE_DEVICE_TABLE(of, bw2_match);
368
369static 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
378static 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
386static void __exit bw2_exit(void)
387{
388	platform_driver_unregister(&bw2_driver);
389}
390
391module_init(bw2_init);
392module_exit(bw2_exit);
393
394MODULE_DESCRIPTION("framebuffer driver for BWTWO chipsets");
395MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
396MODULE_VERSION("2.0");
397MODULE_LICENSE("GPL");
398