xref: /kernel/linux/linux-6.6/drivers/video/fbdev/cg3.c (revision 62306a36)
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.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 cg3_setcolreg(unsigned, unsigned, unsigned, unsigned,
33			 unsigned, struct fb_info *);
34static int cg3_blank(int, struct fb_info *);
35
36static int cg3_mmap(struct fb_info *, struct vm_area_struct *);
37static int cg3_ioctl(struct fb_info *, unsigned int, unsigned long);
38
39/*
40 *  Frame buffer operations
41 */
42
43static const struct fb_ops cg3_ops = {
44	.owner			= THIS_MODULE,
45	.fb_setcolreg		= cg3_setcolreg,
46	.fb_blank		= cg3_blank,
47	.fb_fillrect		= cfb_fillrect,
48	.fb_copyarea		= cfb_copyarea,
49	.fb_imageblit		= cfb_imageblit,
50	.fb_mmap		= cg3_mmap,
51	.fb_ioctl		= cg3_ioctl,
52#ifdef CONFIG_COMPAT
53	.fb_compat_ioctl	= sbusfb_compat_ioctl,
54#endif
55};
56
57
58/* Control Register Constants */
59#define CG3_CR_ENABLE_INTS      0x80
60#define CG3_CR_ENABLE_VIDEO     0x40
61#define CG3_CR_ENABLE_TIMING    0x20
62#define CG3_CR_ENABLE_CURCMP    0x10
63#define CG3_CR_XTAL_MASK        0x0c
64#define CG3_CR_DIVISOR_MASK     0x03
65
66/* Status Register Constants */
67#define CG3_SR_PENDING_INT      0x80
68#define CG3_SR_RES_MASK         0x70
69#define CG3_SR_1152_900_76_A    0x40
70#define CG3_SR_1152_900_76_B    0x60
71#define CG3_SR_ID_MASK          0x0f
72#define CG3_SR_ID_COLOR         0x01
73#define CG3_SR_ID_MONO          0x02
74#define CG3_SR_ID_MONO_ECL      0x03
75
76enum cg3_type {
77	CG3_AT_66HZ = 0,
78	CG3_AT_76HZ,
79	CG3_RDI
80};
81
82struct bt_regs {
83	u32 addr;
84	u32 color_map;
85	u32 control;
86	u32 cursor;
87};
88
89struct cg3_regs {
90	struct bt_regs	cmap;
91	u8	control;
92	u8	status;
93	u8	cursor_start;
94	u8	cursor_end;
95	u8	h_blank_start;
96	u8	h_blank_end;
97	u8	h_sync_start;
98	u8	h_sync_end;
99	u8	comp_sync_end;
100	u8	v_blank_start_high;
101	u8	v_blank_start_low;
102	u8	v_blank_end;
103	u8	v_sync_start;
104	u8	v_sync_end;
105	u8	xfer_holdoff_start;
106	u8	xfer_holdoff_end;
107};
108
109/* Offset of interesting structures in the OBIO space */
110#define CG3_REGS_OFFSET	     0x400000UL
111#define CG3_RAM_OFFSET	     0x800000UL
112
113struct cg3_par {
114	spinlock_t		lock;
115	struct cg3_regs		__iomem *regs;
116	u32			sw_cmap[((256 * 3) + 3) / 4];
117
118	u32			flags;
119#define CG3_FLAG_BLANKED	0x00000001
120#define CG3_FLAG_RDI		0x00000002
121
122	unsigned long		which_io;
123};
124
125/**
126 *      cg3_setcolreg - Optional function. Sets a color register.
127 *      @regno: boolean, 0 copy local, 1 get_user() function
128 *      @red: frame buffer colormap structure
129 *      @green: The green value which can be up to 16 bits wide
130 *      @blue:  The blue value which can be up to 16 bits wide.
131 *      @transp: If supported the alpha value which can be up to 16 bits wide.
132 *      @info: frame buffer info structure
133 *
134 * The cg3 palette is loaded with 4 color values at each time
135 * so you end up with: (rgb)(r), (gb)(rg), (b)(rgb), and so on.
136 * We keep a sw copy of the hw cmap to assist us in this esoteric
137 * loading procedure.
138 */
139static int cg3_setcolreg(unsigned regno,
140			 unsigned red, unsigned green, unsigned blue,
141			 unsigned transp, struct fb_info *info)
142{
143	struct cg3_par *par = (struct cg3_par *) info->par;
144	struct bt_regs __iomem *bt = &par->regs->cmap;
145	unsigned long flags;
146	u32 *p32;
147	u8 *p8;
148	int count;
149
150	if (regno >= 256)
151		return 1;
152
153	red >>= 8;
154	green >>= 8;
155	blue >>= 8;
156
157	spin_lock_irqsave(&par->lock, flags);
158
159	p8 = (u8 *)par->sw_cmap + (regno * 3);
160	p8[0] = red;
161	p8[1] = green;
162	p8[2] = blue;
163
164#define D4M3(x) ((((x)>>2)<<1) + ((x)>>2))      /* (x/4)*3 */
165#define D4M4(x) ((x)&~0x3)                      /* (x/4)*4 */
166
167	count = 3;
168	p32 = &par->sw_cmap[D4M3(regno)];
169	sbus_writel(D4M4(regno), &bt->addr);
170	while (count--)
171		sbus_writel(*p32++, &bt->color_map);
172
173#undef D4M3
174#undef D4M4
175
176	spin_unlock_irqrestore(&par->lock, flags);
177
178	return 0;
179}
180
181/**
182 *      cg3_blank - Optional function.  Blanks the display.
183 *      @blank: the blank mode we want.
184 *      @info: frame buffer structure that represents a single frame buffer
185 */
186static int cg3_blank(int blank, struct fb_info *info)
187{
188	struct cg3_par *par = (struct cg3_par *) info->par;
189	struct cg3_regs __iomem *regs = par->regs;
190	unsigned long flags;
191	u8 val;
192
193	spin_lock_irqsave(&par->lock, flags);
194
195	switch (blank) {
196	case FB_BLANK_UNBLANK: /* Unblanking */
197		val = sbus_readb(&regs->control);
198		val |= CG3_CR_ENABLE_VIDEO;
199		sbus_writeb(val, &regs->control);
200		par->flags &= ~CG3_FLAG_BLANKED;
201		break;
202
203	case FB_BLANK_NORMAL: /* Normal blanking */
204	case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
205	case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
206	case FB_BLANK_POWERDOWN: /* Poweroff */
207		val = sbus_readb(&regs->control);
208		val &= ~CG3_CR_ENABLE_VIDEO;
209		sbus_writeb(val, &regs->control);
210		par->flags |= CG3_FLAG_BLANKED;
211		break;
212	}
213
214	spin_unlock_irqrestore(&par->lock, flags);
215
216	return 0;
217}
218
219static struct sbus_mmap_map cg3_mmap_map[] = {
220	{
221		.voff	= CG3_MMAP_OFFSET,
222		.poff	= CG3_RAM_OFFSET,
223		.size	= SBUS_MMAP_FBSIZE(1)
224	},
225	{ .size = 0 }
226};
227
228static int cg3_mmap(struct fb_info *info, struct vm_area_struct *vma)
229{
230	struct cg3_par *par = (struct cg3_par *)info->par;
231
232	return sbusfb_mmap_helper(cg3_mmap_map,
233				  info->fix.smem_start, info->fix.smem_len,
234				  par->which_io,
235				  vma);
236}
237
238static int cg3_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
239{
240	return sbusfb_ioctl_helper(cmd, arg, info,
241				   FBTYPE_SUN3COLOR, 8, info->fix.smem_len);
242}
243
244/*
245 *  Initialisation
246 */
247
248static void cg3_init_fix(struct fb_info *info, int linebytes,
249			 struct device_node *dp)
250{
251	snprintf(info->fix.id, sizeof(info->fix.id), "%pOFn", dp);
252
253	info->fix.type = FB_TYPE_PACKED_PIXELS;
254	info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
255
256	info->fix.line_length = linebytes;
257
258	info->fix.accel = FB_ACCEL_SUN_CGTHREE;
259}
260
261static void cg3_rdi_maybe_fixup_var(struct fb_var_screeninfo *var,
262				    struct device_node *dp)
263{
264	const char *params;
265	char *p;
266	int ww, hh;
267
268	params = of_get_property(dp, "params", NULL);
269	if (params) {
270		ww = simple_strtoul(params, &p, 10);
271		if (ww && *p == 'x') {
272			hh = simple_strtoul(p + 1, &p, 10);
273			if (hh && *p == '-') {
274				if (var->xres != ww ||
275				    var->yres != hh) {
276					var->xres = var->xres_virtual = ww;
277					var->yres = var->yres_virtual = hh;
278				}
279			}
280		}
281	}
282}
283
284static u8 cg3regvals_66hz[] = {	/* 1152 x 900, 66 Hz */
285	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x04,	0x17, 0x14,
286	0x18, 0xae,	0x19, 0x03,	0x1a, 0xa8,	0x1b, 0x24,
287	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
288	0x10, 0x20,	0
289};
290
291static u8 cg3regvals_76hz[] = {	/* 1152 x 900, 76 Hz */
292	0x14, 0xb7,	0x15, 0x27,	0x16, 0x03,	0x17, 0x0f,
293	0x18, 0xae,	0x19, 0x03,	0x1a, 0xae,	0x1b, 0x2a,
294	0x1c, 0x01,	0x1d, 0x09,	0x1e, 0xff,	0x1f, 0x01,
295	0x10, 0x24,	0
296};
297
298static u8 cg3regvals_rdi[] = {	/* 640 x 480, cgRDI */
299	0x14, 0x70,	0x15, 0x20,	0x16, 0x08,	0x17, 0x10,
300	0x18, 0x06,	0x19, 0x02,	0x1a, 0x31,	0x1b, 0x51,
301	0x1c, 0x06,	0x1d, 0x0c,	0x1e, 0xff,	0x1f, 0x01,
302	0x10, 0x22,	0
303};
304
305static u8 *cg3_regvals[] = {
306	cg3regvals_66hz, cg3regvals_76hz, cg3regvals_rdi
307};
308
309static u_char cg3_dacvals[] = {
310	4, 0xff,	5, 0x00,	6, 0x70,	7, 0x00,	0
311};
312
313static int cg3_do_default_mode(struct cg3_par *par)
314{
315	enum cg3_type type;
316	u8 *p;
317
318	if (par->flags & CG3_FLAG_RDI)
319		type = CG3_RDI;
320	else {
321		u8 status = sbus_readb(&par->regs->status), mon;
322		if ((status & CG3_SR_ID_MASK) == CG3_SR_ID_COLOR) {
323			mon = status & CG3_SR_RES_MASK;
324			if (mon == CG3_SR_1152_900_76_A ||
325			    mon == CG3_SR_1152_900_76_B)
326				type = CG3_AT_76HZ;
327			else
328				type = CG3_AT_66HZ;
329		} else {
330			printk(KERN_ERR "cgthree: can't handle SR %02x\n",
331			       status);
332			return -EINVAL;
333		}
334	}
335
336	for (p = cg3_regvals[type]; *p; p += 2) {
337		u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
338		sbus_writeb(p[1], regp);
339	}
340	for (p = cg3_dacvals; *p; p += 2) {
341		u8 __iomem *regp;
342
343		regp = (u8 __iomem *)&par->regs->cmap.addr;
344		sbus_writeb(p[0], regp);
345		regp = (u8 __iomem *)&par->regs->cmap.control;
346		sbus_writeb(p[1], regp);
347	}
348	return 0;
349}
350
351static int cg3_probe(struct platform_device *op)
352{
353	struct device_node *dp = op->dev.of_node;
354	struct fb_info *info;
355	struct cg3_par *par;
356	int linebytes, err;
357
358	info = framebuffer_alloc(sizeof(struct cg3_par), &op->dev);
359
360	err = -ENOMEM;
361	if (!info)
362		goto out_err;
363	par = info->par;
364
365	spin_lock_init(&par->lock);
366
367	info->fix.smem_start = op->resource[0].start;
368	par->which_io = op->resource[0].flags & IORESOURCE_BITS;
369
370	sbusfb_fill_var(&info->var, dp, 8);
371	info->var.red.length = 8;
372	info->var.green.length = 8;
373	info->var.blue.length = 8;
374	if (of_node_name_eq(dp, "cgRDI"))
375		par->flags |= CG3_FLAG_RDI;
376	if (par->flags & CG3_FLAG_RDI)
377		cg3_rdi_maybe_fixup_var(&info->var, dp);
378
379	linebytes = of_getintprop_default(dp, "linebytes",
380					  info->var.xres);
381	info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
382
383	par->regs = of_ioremap(&op->resource[0], CG3_REGS_OFFSET,
384			       sizeof(struct cg3_regs), "cg3 regs");
385	if (!par->regs)
386		goto out_release_fb;
387
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_property_present(dp, "width")) {
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
421out_dealloc_cmap:
422	fb_dealloc_cmap(&info->cmap);
423
424out_unmap_screen:
425	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
426
427out_unmap_regs:
428	of_iounmap(&op->resource[0], par->regs, sizeof(struct cg3_regs));
429
430out_release_fb:
431	framebuffer_release(info);
432
433out_err:
434	return err;
435}
436
437static void 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
451static const struct of_device_id cg3_match[] = {
452	{
453		.name = "cgthree",
454	},
455	{
456		.name = "cgRDI",
457	},
458	{},
459};
460MODULE_DEVICE_TABLE(of, cg3_match);
461
462static struct platform_driver cg3_driver = {
463	.driver = {
464		.name = "cg3",
465		.of_match_table = cg3_match,
466	},
467	.probe		= cg3_probe,
468	.remove_new	= cg3_remove,
469};
470
471static int __init cg3_init(void)
472{
473	if (fb_get_options("cg3fb", NULL))
474		return -ENODEV;
475
476	return platform_driver_register(&cg3_driver);
477}
478
479static void __exit cg3_exit(void)
480{
481	platform_driver_unregister(&cg3_driver);
482}
483
484module_init(cg3_init);
485module_exit(cg3_exit);
486
487MODULE_DESCRIPTION("framebuffer driver for CGthree chipsets");
488MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
489MODULE_VERSION("2.0");
490MODULE_LICENSE("GPL");
491