1/*
2 * linux/drivers/video/pmagb-b-fb.c
3 *
4 * PMAGB-B TURBOchannel Smart Frame Buffer (SFB) 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 * DECstation related code Copyright (C) 1999, 2000, 2001 by
11 * Michael Engel <engel@unix-ag.org>,
12 * Karsten Merker <merker@linuxtag.org> and
13 * Harald Koerfgen.
14 * Copyright (c) 2005, 2006 Maciej W. Rozycki
15 *
16 * This file is subject to the terms and conditions of the GNU General
17 * Public License. See the file COPYING in the main directory of this
18 * archive for more details.
19 */
20
21#include <linux/compiler.h>
22#include <linux/delay.h>
23#include <linux/errno.h>
24#include <linux/fb.h>
25#include <linux/init.h>
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/tc.h>
29#include <linux/types.h>
30
31#include <asm/io.h>
32
33#include <video/pmagb-b-fb.h>
34
35
36struct pmagbbfb_par {
37 volatile void __iomem *mmio;
38 volatile void __iomem *smem;
39 volatile u32 __iomem *sfb;
40 volatile u32 __iomem *dac;
41 unsigned int osc0;
42 unsigned int osc1;
43 int slot;
44};
45
46
47static const struct fb_var_screeninfo pmagbbfb_defined = {
48 .bits_per_pixel = 8,
49 .red.length = 8,
50 .green.length = 8,
51 .blue.length = 8,
52 .activate = FB_ACTIVATE_NOW,
53 .height = -1,
54 .width = -1,
55 .accel_flags = FB_ACCEL_NONE,
56 .sync = FB_SYNC_ON_GREEN,
57 .vmode = FB_VMODE_NONINTERLACED,
58};
59
60static const struct fb_fix_screeninfo pmagbbfb_fix = {
61 .id = "PMAGB-BA",
62 .smem_len = (2048 * 1024),
63 .type = FB_TYPE_PACKED_PIXELS,
64 .visual = FB_VISUAL_PSEUDOCOLOR,
65 .mmio_len = PMAGB_B_FBMEM,
66};
67
68
69static inline void sfb_write(struct pmagbbfb_par *par, unsigned int reg, u32 v)
70{
71 writel(val: v, addr: par->sfb + reg / 4);
72}
73
74static inline u32 sfb_read(struct pmagbbfb_par *par, unsigned int reg)
75{
76 return readl(addr: par->sfb + reg / 4);
77}
78
79static inline void dac_write(struct pmagbbfb_par *par, unsigned int reg, u8 v)
80{
81 writeb(val: v, addr: par->dac + reg / 4);
82}
83
84static inline u8 dac_read(struct pmagbbfb_par *par, unsigned int reg)
85{
86 return readb(addr: par->dac + reg / 4);
87}
88
89static inline void gp0_write(struct pmagbbfb_par *par, u32 v)
90{
91 writel(val: v, addr: par->mmio + PMAGB_B_GP0);
92}
93
94
95/*
96 * Set the palette.
97 */
98static int pmagbbfb_setcolreg(unsigned int regno, unsigned int red,
99 unsigned int green, unsigned int blue,
100 unsigned int transp, struct fb_info *info)
101{
102 struct pmagbbfb_par *par = info->par;
103
104 if (regno >= info->cmap.len)
105 return 1;
106
107 red >>= 8; /* The cmap fields are 16 bits */
108 green >>= 8; /* wide, but the hardware colormap */
109 blue >>= 8; /* registers are only 8 bits wide */
110
111 mb();
112 dac_write(par, BT459_ADDR_LO, v: regno);
113 dac_write(par, BT459_ADDR_HI, v: 0x00);
114 wmb();
115 dac_write(par, BT459_CMAP, v: red);
116 wmb();
117 dac_write(par, BT459_CMAP, v: green);
118 wmb();
119 dac_write(par, BT459_CMAP, v: blue);
120
121 return 0;
122}
123
124static const struct fb_ops pmagbbfb_ops = {
125 .owner = THIS_MODULE,
126 FB_DEFAULT_IOMEM_OPS,
127 .fb_setcolreg = pmagbbfb_setcolreg,
128};
129
130
131/*
132 * Turn the hardware cursor off.
133 */
134static void pmagbbfb_erase_cursor(struct fb_info *info)
135{
136 struct pmagbbfb_par *par = info->par;
137
138 mb();
139 dac_write(par, BT459_ADDR_LO, v: 0x00);
140 dac_write(par, BT459_ADDR_HI, v: 0x03);
141 wmb();
142 dac_write(par, BT459_DATA, v: 0x00);
143}
144
145/*
146 * Set up screen parameters.
147 */
148static void pmagbbfb_screen_setup(struct fb_info *info)
149{
150 struct pmagbbfb_par *par = info->par;
151
152 info->var.xres = ((sfb_read(par, SFB_REG_VID_HOR) >>
153 SFB_VID_HOR_PIX_SHIFT) & SFB_VID_HOR_PIX_MASK) * 4;
154 info->var.xres_virtual = info->var.xres;
155 info->var.yres = (sfb_read(par, SFB_REG_VID_VER) >>
156 SFB_VID_VER_SL_SHIFT) & SFB_VID_VER_SL_MASK;
157 info->var.yres_virtual = info->var.yres;
158 info->var.left_margin = ((sfb_read(par, SFB_REG_VID_HOR) >>
159 SFB_VID_HOR_BP_SHIFT) &
160 SFB_VID_HOR_BP_MASK) * 4;
161 info->var.right_margin = ((sfb_read(par, SFB_REG_VID_HOR) >>
162 SFB_VID_HOR_FP_SHIFT) &
163 SFB_VID_HOR_FP_MASK) * 4;
164 info->var.upper_margin = (sfb_read(par, SFB_REG_VID_VER) >>
165 SFB_VID_VER_BP_SHIFT) & SFB_VID_VER_BP_MASK;
166 info->var.lower_margin = (sfb_read(par, SFB_REG_VID_VER) >>
167 SFB_VID_VER_FP_SHIFT) & SFB_VID_VER_FP_MASK;
168 info->var.hsync_len = ((sfb_read(par, SFB_REG_VID_HOR) >>
169 SFB_VID_HOR_SYN_SHIFT) &
170 SFB_VID_HOR_SYN_MASK) * 4;
171 info->var.vsync_len = (sfb_read(par, SFB_REG_VID_VER) >>
172 SFB_VID_VER_SYN_SHIFT) & SFB_VID_VER_SYN_MASK;
173
174 info->fix.line_length = info->var.xres;
175};
176
177/*
178 * Determine oscillator configuration.
179 */
180static void pmagbbfb_osc_setup(struct fb_info *info)
181{
182 static unsigned int pmagbbfb_freqs[] = {
183 130808, 119843, 104000, 92980, 74370, 72800,
184 69197, 66000, 65000, 50350, 36000, 32000, 25175
185 };
186 struct pmagbbfb_par *par = info->par;
187 struct tc_bus *tbus = to_tc_dev(info->device)->bus;
188 u32 count0 = 8, count1 = 8, counttc = 16 * 256 + 8;
189 u32 freq0, freq1, freqtc = tc_get_speed(tbus) / 250;
190 int i, j;
191
192 gp0_write(par, v: 0); /* select Osc0 */
193 for (j = 0; j < 16; j++) {
194 mb();
195 sfb_write(par, SFB_REG_TCCLK_COUNT, v: 0);
196 mb();
197 for (i = 0; i < 100; i++) { /* nominally max. 20.5us */
198 if (sfb_read(par, SFB_REG_TCCLK_COUNT) == 0)
199 break;
200 udelay(1);
201 }
202 count0 += sfb_read(par, SFB_REG_VIDCLK_COUNT);
203 }
204
205 gp0_write(par, v: 1); /* select Osc1 */
206 for (j = 0; j < 16; j++) {
207 mb();
208 sfb_write(par, SFB_REG_TCCLK_COUNT, v: 0);
209
210 for (i = 0; i < 100; i++) { /* nominally max. 20.5us */
211 if (sfb_read(par, SFB_REG_TCCLK_COUNT) == 0)
212 break;
213 udelay(1);
214 }
215 count1 += sfb_read(par, SFB_REG_VIDCLK_COUNT);
216 }
217
218 freq0 = (freqtc * count0 + counttc / 2) / counttc;
219 par->osc0 = freq0;
220 if (freq0 >= pmagbbfb_freqs[0] - (pmagbbfb_freqs[0] + 32) / 64 &&
221 freq0 <= pmagbbfb_freqs[0] + (pmagbbfb_freqs[0] + 32) / 64)
222 par->osc0 = pmagbbfb_freqs[0];
223
224 freq1 = (par->osc0 * count1 + count0 / 2) / count0;
225 par->osc1 = freq1;
226 for (i = 0; i < ARRAY_SIZE(pmagbbfb_freqs); i++)
227 if (freq1 >= pmagbbfb_freqs[i] -
228 (pmagbbfb_freqs[i] + 128) / 256 &&
229 freq1 <= pmagbbfb_freqs[i] +
230 (pmagbbfb_freqs[i] + 128) / 256) {
231 par->osc1 = pmagbbfb_freqs[i];
232 break;
233 }
234
235 if (par->osc0 - par->osc1 <= (par->osc0 + par->osc1 + 256) / 512 ||
236 par->osc1 - par->osc0 <= (par->osc0 + par->osc1 + 256) / 512)
237 par->osc1 = 0;
238
239 gp0_write(par, v: par->osc1 != 0); /* reselect OscX */
240
241 info->var.pixclock = par->osc1 ?
242 (1000000000 + par->osc1 / 2) / par->osc1 :
243 (1000000000 + par->osc0 / 2) / par->osc0;
244};
245
246
247static int pmagbbfb_probe(struct device *dev)
248{
249 struct tc_dev *tdev = to_tc_dev(dev);
250 resource_size_t start, len;
251 struct fb_info *info;
252 struct pmagbbfb_par *par;
253 char freq0[12], freq1[12];
254 u32 vid_base;
255 int err;
256
257 info = framebuffer_alloc(size: sizeof(struct pmagbbfb_par), dev);
258 if (!info)
259 return -ENOMEM;
260
261 par = info->par;
262 dev_set_drvdata(dev, data: info);
263
264 if (fb_alloc_cmap(cmap: &info->cmap, len: 256, transp: 0) < 0) {
265 printk(KERN_ERR "%s: Cannot allocate color map\n",
266 dev_name(dev));
267 err = -ENOMEM;
268 goto err_alloc;
269 }
270
271 info->fbops = &pmagbbfb_ops;
272 info->fix = pmagbbfb_fix;
273 info->var = pmagbbfb_defined;
274
275 /* Request the I/O MEM resource. */
276 start = tdev->resource.start;
277 len = tdev->resource.end - start + 1;
278 if (!request_mem_region(start, len, dev_name(dev))) {
279 printk(KERN_ERR "%s: Cannot reserve FB region\n",
280 dev_name(dev));
281 err = -EBUSY;
282 goto err_cmap;
283 }
284
285 /* MMIO mapping setup. */
286 info->fix.mmio_start = start;
287 par->mmio = ioremap(offset: info->fix.mmio_start, size: info->fix.mmio_len);
288 if (!par->mmio) {
289 printk(KERN_ERR "%s: Cannot map MMIO\n", dev_name(dev));
290 err = -ENOMEM;
291 goto err_resource;
292 }
293 par->sfb = par->mmio + PMAGB_B_SFB;
294 par->dac = par->mmio + PMAGB_B_BT459;
295
296 /* Frame buffer mapping setup. */
297 info->fix.smem_start = start + PMAGB_B_FBMEM;
298 par->smem = ioremap(offset: info->fix.smem_start, size: info->fix.smem_len);
299 if (!par->smem) {
300 printk(KERN_ERR "%s: Cannot map FB\n", dev_name(dev));
301 err = -ENOMEM;
302 goto err_mmio_map;
303 }
304 vid_base = sfb_read(par, SFB_REG_VID_BASE);
305 info->screen_base = (void __iomem *)par->smem + vid_base * 0x1000;
306 info->screen_size = info->fix.smem_len - 2 * vid_base * 0x1000;
307
308 pmagbbfb_erase_cursor(info);
309 pmagbbfb_screen_setup(info);
310 pmagbbfb_osc_setup(info);
311
312 err = register_framebuffer(fb_info: info);
313 if (err < 0) {
314 printk(KERN_ERR "%s: Cannot register framebuffer\n",
315 dev_name(dev));
316 goto err_smem_map;
317 }
318
319 get_device(dev);
320
321 snprintf(buf: freq0, size: sizeof(freq0), fmt: "%u.%03uMHz",
322 par->osc0 / 1000, par->osc0 % 1000);
323 snprintf(buf: freq1, size: sizeof(freq1), fmt: "%u.%03uMHz",
324 par->osc1 / 1000, par->osc1 % 1000);
325
326 fb_info(info, "%s frame buffer device at %s\n",
327 info->fix.id, dev_name(dev));
328 fb_info(info, "Osc0: %s, Osc1: %s, Osc%u selected\n",
329 freq0, par->osc1 ? freq1 : "disabled", par->osc1 != 0);
330
331 return 0;
332
333
334err_smem_map:
335 iounmap(addr: par->smem);
336
337err_mmio_map:
338 iounmap(addr: par->mmio);
339
340err_resource:
341 release_mem_region(start, len);
342
343err_cmap:
344 fb_dealloc_cmap(cmap: &info->cmap);
345
346err_alloc:
347 framebuffer_release(info);
348 return err;
349}
350
351static int pmagbbfb_remove(struct device *dev)
352{
353 struct tc_dev *tdev = to_tc_dev(dev);
354 struct fb_info *info = dev_get_drvdata(dev);
355 struct pmagbbfb_par *par = info->par;
356 resource_size_t start, len;
357
358 put_device(dev);
359 unregister_framebuffer(fb_info: info);
360 iounmap(addr: par->smem);
361 iounmap(addr: par->mmio);
362 start = tdev->resource.start;
363 len = tdev->resource.end - start + 1;
364 release_mem_region(start, len);
365 fb_dealloc_cmap(cmap: &info->cmap);
366 framebuffer_release(info);
367 return 0;
368}
369
370
371/*
372 * Initialize the framebuffer.
373 */
374static const struct tc_device_id pmagbbfb_tc_table[] = {
375 { "DEC ", "PMAGB-BA" },
376 { }
377};
378MODULE_DEVICE_TABLE(tc, pmagbbfb_tc_table);
379
380static struct tc_driver pmagbbfb_driver = {
381 .id_table = pmagbbfb_tc_table,
382 .driver = {
383 .name = "pmagbbfb",
384 .bus = &tc_bus_type,
385 .probe = pmagbbfb_probe,
386 .remove = pmagbbfb_remove,
387 },
388};
389
390static int __init pmagbbfb_init(void)
391{
392#ifndef MODULE
393 if (fb_get_options(name: "pmagbbfb", NULL))
394 return -ENXIO;
395#endif
396 return tc_register_driver(tdrv: &pmagbbfb_driver);
397}
398
399static void __exit pmagbbfb_exit(void)
400{
401 tc_unregister_driver(tdrv: &pmagbbfb_driver);
402}
403
404
405module_init(pmagbbfb_init);
406module_exit(pmagbbfb_exit);
407
408MODULE_LICENSE("GPL");
409

source code of linux/drivers/video/fbdev/pmagb-b-fb.c