maxinefb.c

  1/*
  2 *      linux/drivers/video/maxinefb.c
  3 *
  4 *	DECstation 5000/xx onboard framebuffer support ... derived from:
  5 *	"HP300 Topcat framebuffer support (derived from macfb of all things)
  6 *	Phil Blundell <philb@gnu.org> 1998", the original code can be
  7 *      found in the file hpfb.c in the same directory.
  8 *
  9 *      DECstation related code Copyright (C) 1999,2000,2001 by
 10 *      Michael Engel <engel@unix-ag.org> and
 11 *      Karsten Merker <merker@linuxtag.org>.
 12 *      This file is subject to the terms and conditions of the GNU General
 13 *      Public License.  See the file COPYING in the main directory of this
 14 *      archive for more details.
 15 *
 16 */
 17
 18/*
 19 * Changes:
 20 * 2001/01/27 removed debugging and testing code, fixed fb_ops
 21 *            initialization which had caused a crash before,
 22 *            general cleanup, first official release (KM)
 23 *
 24 */
 25
 26#include <linux/module.h>
 27#include <linux/kernel.h>
 28#include <linux/errno.h>
 29#include <linux/string.h>
 30#include <linux/mm.h>
 31#include <linux/delay.h>
 32#include <linux/init.h>
 33#include <linux/fb.h>
 34#include <video/maxinefb.h>
 35
 36/* bootinfo.h defines the machine type values, needed when checking */
 37/* whether are really running on a maxine, KM                       */
 38#include <asm/bootinfo.h>
 39
 40static struct fb_info fb_info;
 41
 42static const struct fb_var_screeninfo maxinefb_defined = {
 43	.xres =		1024,
 44	.yres =		768,
 45	.xres_virtual =	1024,
 46	.yres_virtual =	768,
 47	.bits_per_pixel =8,
 48	.activate =	FB_ACTIVATE_NOW,
 49	.height =	-1,
 50	.width =	-1,
 51	.vmode =	FB_VMODE_NONINTERLACED,
 52};
 53
 54static struct fb_fix_screeninfo maxinefb_fix __initdata = {
 55	.id =		"Maxine",
 56	.smem_len =	(1024*768),
 57	.type =		FB_TYPE_PACKED_PIXELS,
 58	.visual =	FB_VISUAL_PSEUDOCOLOR,
 59	.line_length =	1024,
 60};
 61
 62/* Handle the funny Inmos RamDAC/video controller ... */
 63
 64void maxinefb_ims332_write_register(int regno, register unsigned int val)
 65{
 66	register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
 67	unsigned char *wptr;
 68
 69	wptr = regs + 0xa0000 + (regno << 4);
 70	*((volatile unsigned int *) (regs)) = (val >> 8) & 0xff00;
 71	*((volatile unsigned short *) (wptr)) = val;
 72}
 73
 74unsigned int maxinefb_ims332_read_register(int regno)
 75{
 76	register unsigned char *regs = (char *) MAXINEFB_IMS332_ADDRESS;
 77	unsigned char *rptr;
 78	register unsigned int j, k;
 79
 80	rptr = regs + 0x80000 + (regno << 4);
 81	j = *((volatile unsigned short *) rptr);
 82	k = *((volatile unsigned short *) regs);
 83
 84	return (j & 0xffff) | ((k & 0xff00) << 8);
 85}
 86
 87/* Set the palette */
 88static int maxinefb_setcolreg(unsigned regno, unsigned red, unsigned green,
 89			      unsigned blue, unsigned transp, struct fb_info *info)
 90{
 91	/* value to be written into the palette reg. */
 92	unsigned long hw_colorvalue = 0;
 93
 94	if (regno > 255)
 95		return 1;
 96
 97	red   >>= 8;    /* The cmap fields are 16 bits    */
 98	green >>= 8;    /* wide, but the harware colormap */
 99	blue  >>= 8;    /* registers are only 8 bits wide */
100
101	hw_colorvalue = (blue << 16) + (green << 8) + (red);
102
103	maxinefb_ims332_write_register(IMS332_REG_COLOR_PALETTE + regno,
104				       hw_colorvalue);
105	return 0;
106}
107
108static const struct fb_ops maxinefb_ops = {
109	.owner		= THIS_MODULE,
110	FB_DEFAULT_IOMEM_OPS,
111	.fb_setcolreg	= maxinefb_setcolreg,
112};
113
114int __init maxinefb_init(void)
115{
116	unsigned long fboff;
117	unsigned long fb_start;
118	int i;
119
120	if (fb_get_options("maxinefb", NULL))
121		return -ENODEV;
122
123	/* Validate we're on the proper machine type */
124	if (mips_machtype != MACH_DS5000_XX) {
125		return -EINVAL;
126	}
127
128	printk(KERN_INFO "Maxinefb: Personal DECstation detected\n");
129	printk(KERN_INFO "Maxinefb: initializing onboard framebuffer\n");
130
131	/* Framebuffer display memory base address */
132	fb_start = DS5000_xx_ONBOARD_FBMEM_START;
133
134	/* Clear screen */
135	for (fboff = fb_start; fboff < fb_start + 0x1ffff; fboff++)
136		*(volatile unsigned char *)fboff = 0x0;
137
138	maxinefb_fix.smem_start = fb_start;
139
140	/* erase hardware cursor */
141	for (i = 0; i < 512; i++) {
142		maxinefb_ims332_write_register(IMS332_REG_CURSOR_RAM + i,
143					       0);
144		/*
145		   if (i&0x8 == 0)
146		   maxinefb_ims332_write_register (IMS332_REG_CURSOR_RAM + i, 0x0f);
147		   else
148		   maxinefb_ims332_write_register (IMS332_REG_CURSOR_RAM + i, 0xf0);
149		 */
150	}
151
152	fb_info.fbops = &maxinefb_ops;
153	fb_info.screen_base = (char *)maxinefb_fix.smem_start;
154	fb_info.var = maxinefb_defined;
155	fb_info.fix = maxinefb_fix;
156
157	fb_alloc_cmap(&fb_info.cmap, 256, 0);
158
159	if (register_framebuffer(&fb_info) < 0)
160		return 1;
161	return 0;
162}
163
164static void __exit maxinefb_exit(void)
165{
166	unregister_framebuffer(&fb_info);
167}
168
169#ifdef MODULE
170MODULE_LICENSE("GPL");
171#endif
172module_init(maxinefb_init);
173module_exit(maxinefb_exit);
174