xref: /openbmc/linux/drivers/video/fbdev/pmag-ba-fb.c (revision 4f6cce39)
1 /*
2  *	linux/drivers/video/pmag-ba-fb.c
3  *
4  *	PMAG-BA TURBOchannel Color Frame Buffer (CFB) card support,
5  *	derived from:
6  *	"HP300 Topcat framebuffer support (derived from macfb of all things)
7  *	Phil Blundell <philb@gnu.org> 1998", the original code can be
8  *	found in the file hpfb.c in the same directory.
9  *
10  *	Based on digital document:
11  * 	"PMAG-BA TURBOchannel Color Frame Buffer
12  *	 Functional Specification", Revision 1.2, August 27, 1990
13  *
14  *	DECstation related code Copyright (C) 1999, 2000, 2001 by
15  *	Michael Engel <engel@unix-ag.org>,
16  *	Karsten Merker <merker@linuxtag.org> and
17  *	Harald Koerfgen.
18  *	Copyright (c) 2005, 2006  Maciej W. Rozycki
19  *	Copyright (c) 2005  James Simmons
20  *
21  *	This file is subject to the terms and conditions of the GNU General
22  *	Public License.  See the file COPYING in the main directory of this
23  *	archive for more details.
24  */
25 
26 #include <linux/compiler.h>
27 #include <linux/errno.h>
28 #include <linux/fb.h>
29 #include <linux/init.h>
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/tc.h>
33 #include <linux/types.h>
34 
35 #include <asm/io.h>
36 
37 #include <video/pmag-ba-fb.h>
38 
39 
40 struct pmagbafb_par {
41 	volatile void __iomem *mmio;
42 	volatile u32 __iomem *dac;
43 };
44 
45 
46 static struct fb_var_screeninfo pmagbafb_defined = {
47 	.xres		= 1024,
48 	.yres		= 864,
49 	.xres_virtual	= 1024,
50 	.yres_virtual	= 864,
51 	.bits_per_pixel	= 8,
52 	.red.length	= 8,
53 	.green.length	= 8,
54 	.blue.length	= 8,
55 	.activate	= FB_ACTIVATE_NOW,
56 	.height		= -1,
57 	.width		= -1,
58 	.accel_flags	= FB_ACCEL_NONE,
59 	.pixclock	= 14452,
60 	.left_margin	= 116,
61 	.right_margin	= 12,
62 	.upper_margin	= 34,
63 	.lower_margin	= 0,
64 	.hsync_len	= 128,
65 	.vsync_len	= 3,
66 	.sync		= FB_SYNC_ON_GREEN,
67 	.vmode		= FB_VMODE_NONINTERLACED,
68 };
69 
70 static struct fb_fix_screeninfo pmagbafb_fix = {
71 	.id		= "PMAG-BA",
72 	.smem_len	= (1024 * 1024),
73 	.type		= FB_TYPE_PACKED_PIXELS,
74 	.visual		= FB_VISUAL_PSEUDOCOLOR,
75 	.line_length	= 1024,
76 	.mmio_len	= PMAG_BA_SIZE - PMAG_BA_BT459,
77 };
78 
79 
80 static inline void dac_write(struct pmagbafb_par *par, unsigned int reg, u8 v)
81 {
82 	writeb(v, par->dac + reg / 4);
83 }
84 
85 static inline u8 dac_read(struct pmagbafb_par *par, unsigned int reg)
86 {
87 	return readb(par->dac + reg / 4);
88 }
89 
90 
91 /*
92  * Set the palette.
93  */
94 static int pmagbafb_setcolreg(unsigned int regno, unsigned int red,
95 			      unsigned int green, unsigned int blue,
96 			      unsigned int transp, struct fb_info *info)
97 {
98 	struct pmagbafb_par *par = info->par;
99 
100 	if (regno >= info->cmap.len)
101 		return 1;
102 
103 	red   >>= 8;	/* The cmap fields are 16 bits    */
104 	green >>= 8;	/* wide, but the hardware colormap */
105 	blue  >>= 8;	/* registers are only 8 bits wide */
106 
107 	mb();
108 	dac_write(par, BT459_ADDR_LO, regno);
109 	dac_write(par, BT459_ADDR_HI, 0x00);
110 	wmb();
111 	dac_write(par, BT459_CMAP, red);
112 	wmb();
113 	dac_write(par, BT459_CMAP, green);
114 	wmb();
115 	dac_write(par, BT459_CMAP, blue);
116 
117 	return 0;
118 }
119 
120 static struct fb_ops pmagbafb_ops = {
121 	.owner		= THIS_MODULE,
122 	.fb_setcolreg	= pmagbafb_setcolreg,
123 	.fb_fillrect	= cfb_fillrect,
124 	.fb_copyarea	= cfb_copyarea,
125 	.fb_imageblit	= cfb_imageblit,
126 };
127 
128 
129 /*
130  * Turn the hardware cursor off.
131  */
132 static void pmagbafb_erase_cursor(struct fb_info *info)
133 {
134 	struct pmagbafb_par *par = info->par;
135 
136 	mb();
137 	dac_write(par, BT459_ADDR_LO, 0x00);
138 	dac_write(par, BT459_ADDR_HI, 0x03);
139 	wmb();
140 	dac_write(par, BT459_DATA, 0x00);
141 }
142 
143 
144 static int pmagbafb_probe(struct device *dev)
145 {
146 	struct tc_dev *tdev = to_tc_dev(dev);
147 	resource_size_t start, len;
148 	struct fb_info *info;
149 	struct pmagbafb_par *par;
150 	int err;
151 
152 	info = framebuffer_alloc(sizeof(struct pmagbafb_par), dev);
153 	if (!info) {
154 		printk(KERN_ERR "%s: Cannot allocate memory\n", dev_name(dev));
155 		return -ENOMEM;
156 	}
157 
158 	par = info->par;
159 	dev_set_drvdata(dev, info);
160 
161 	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
162 		printk(KERN_ERR "%s: Cannot allocate color map\n",
163 		       dev_name(dev));
164 		err = -ENOMEM;
165 		goto err_alloc;
166 	}
167 
168 	info->fbops = &pmagbafb_ops;
169 	info->fix = pmagbafb_fix;
170 	info->var = pmagbafb_defined;
171 	info->flags = FBINFO_DEFAULT;
172 
173 	/* Request the I/O MEM resource.  */
174 	start = tdev->resource.start;
175 	len = tdev->resource.end - start + 1;
176 	if (!request_mem_region(start, len, dev_name(dev))) {
177 		printk(KERN_ERR "%s: Cannot reserve FB region\n",
178 		       dev_name(dev));
179 		err = -EBUSY;
180 		goto err_cmap;
181 	}
182 
183 	/* MMIO mapping setup.  */
184 	info->fix.mmio_start = start;
185 	par->mmio = ioremap_nocache(info->fix.mmio_start, info->fix.mmio_len);
186 	if (!par->mmio) {
187 		printk(KERN_ERR "%s: Cannot map MMIO\n", dev_name(dev));
188 		err = -ENOMEM;
189 		goto err_resource;
190 	}
191 	par->dac = par->mmio + PMAG_BA_BT459;
192 
193 	/* Frame buffer mapping setup.  */
194 	info->fix.smem_start = start + PMAG_BA_FBMEM;
195 	info->screen_base = ioremap_nocache(info->fix.smem_start,
196 					    info->fix.smem_len);
197 	if (!info->screen_base) {
198 		printk(KERN_ERR "%s: Cannot map FB\n", dev_name(dev));
199 		err = -ENOMEM;
200 		goto err_mmio_map;
201 	}
202 	info->screen_size = info->fix.smem_len;
203 
204 	pmagbafb_erase_cursor(info);
205 
206 	err = register_framebuffer(info);
207 	if (err < 0) {
208 		printk(KERN_ERR "%s: Cannot register framebuffer\n",
209 		       dev_name(dev));
210 		goto err_smem_map;
211 	}
212 
213 	get_device(dev);
214 
215 	fb_info(info, "%s frame buffer device at %s\n",
216 		info->fix.id, dev_name(dev));
217 
218 	return 0;
219 
220 
221 err_smem_map:
222 	iounmap(info->screen_base);
223 
224 err_mmio_map:
225 	iounmap(par->mmio);
226 
227 err_resource:
228 	release_mem_region(start, len);
229 
230 err_cmap:
231 	fb_dealloc_cmap(&info->cmap);
232 
233 err_alloc:
234 	framebuffer_release(info);
235 	return err;
236 }
237 
238 static int __exit pmagbafb_remove(struct device *dev)
239 {
240 	struct tc_dev *tdev = to_tc_dev(dev);
241 	struct fb_info *info = dev_get_drvdata(dev);
242 	struct pmagbafb_par *par = info->par;
243 	resource_size_t start, len;
244 
245 	put_device(dev);
246 	unregister_framebuffer(info);
247 	iounmap(info->screen_base);
248 	iounmap(par->mmio);
249 	start = tdev->resource.start;
250 	len = tdev->resource.end - start + 1;
251 	release_mem_region(start, len);
252 	fb_dealloc_cmap(&info->cmap);
253 	framebuffer_release(info);
254 	return 0;
255 }
256 
257 
258 /*
259  * Initialize the framebuffer.
260  */
261 static const struct tc_device_id pmagbafb_tc_table[] = {
262 	{ "DEC     ", "PMAG-BA " },
263 	{ }
264 };
265 MODULE_DEVICE_TABLE(tc, pmagbafb_tc_table);
266 
267 static struct tc_driver pmagbafb_driver = {
268 	.id_table	= pmagbafb_tc_table,
269 	.driver		= {
270 		.name	= "pmagbafb",
271 		.bus	= &tc_bus_type,
272 		.probe	= pmagbafb_probe,
273 		.remove	= __exit_p(pmagbafb_remove),
274 	},
275 };
276 
277 static int __init pmagbafb_init(void)
278 {
279 #ifndef MODULE
280 	if (fb_get_options("pmagbafb", NULL))
281 		return -ENXIO;
282 #endif
283 	return tc_register_driver(&pmagbafb_driver);
284 }
285 
286 static void __exit pmagbafb_exit(void)
287 {
288 	tc_unregister_driver(&pmagbafb_driver);
289 }
290 
291 
292 module_init(pmagbafb_init);
293 module_exit(pmagbafb_exit);
294 
295 MODULE_LICENSE("GPL");
296