xref: /openbmc/linux/drivers/video/fbdev/gxt4500.c (revision 4f6cce39)
1 /*
2  * Frame buffer device for IBM GXT4500P/6500P and GXT4000P/6000P
3  * display adaptors
4  *
5  * Copyright (C) 2006 Paul Mackerras, IBM Corp. <paulus@samba.org>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/fb.h>
11 #include <linux/console.h>
12 #include <linux/pci.h>
13 #include <linux/pci_ids.h>
14 #include <linux/delay.h>
15 #include <linux/string.h>
16 
17 #define PCI_DEVICE_ID_IBM_GXT4500P	0x21c
18 #define PCI_DEVICE_ID_IBM_GXT6500P	0x21b
19 #define PCI_DEVICE_ID_IBM_GXT4000P	0x16e
20 #define PCI_DEVICE_ID_IBM_GXT6000P	0x170
21 
22 /* GXT4500P registers */
23 
24 /* Registers in PCI config space */
25 #define CFG_ENDIAN0		0x40
26 
27 /* Misc control/status registers */
28 #define STATUS			0x1000
29 #define CTRL_REG0		0x1004
30 #define   CR0_HALT_DMA			0x4
31 #define   CR0_RASTER_RESET		0x8
32 #define   CR0_GEOM_RESET		0x10
33 #define   CR0_MEM_CTRLER_RESET		0x20
34 
35 /* Framebuffer control registers */
36 #define FB_AB_CTRL		0x1100
37 #define FB_CD_CTRL		0x1104
38 #define FB_WID_CTRL		0x1108
39 #define FB_Z_CTRL		0x110c
40 #define FB_VGA_CTRL		0x1110
41 #define REFRESH_AB_CTRL		0x1114
42 #define REFRESH_CD_CTRL		0x1118
43 #define FB_OVL_CTRL		0x111c
44 #define   FB_CTRL_TYPE			0x80000000
45 #define   FB_CTRL_WIDTH_MASK		0x007f0000
46 #define   FB_CTRL_WIDTH_SHIFT		16
47 #define   FB_CTRL_START_SEG_MASK	0x00003fff
48 
49 #define REFRESH_START		0x1098
50 #define REFRESH_SIZE		0x109c
51 
52 /* "Direct" framebuffer access registers */
53 #define DFA_FB_A		0x11e0
54 #define DFA_FB_B		0x11e4
55 #define DFA_FB_C		0x11e8
56 #define DFA_FB_D		0x11ec
57 #define   DFA_FB_ENABLE			0x80000000
58 #define   DFA_FB_BASE_MASK		0x03f00000
59 #define   DFA_FB_STRIDE_1k		0x00000000
60 #define   DFA_FB_STRIDE_2k		0x00000010
61 #define   DFA_FB_STRIDE_4k		0x00000020
62 #define   DFA_PIX_8BIT			0x00000000
63 #define   DFA_PIX_16BIT_565		0x00000001
64 #define   DFA_PIX_16BIT_1555		0x00000002
65 #define   DFA_PIX_24BIT			0x00000004
66 #define   DFA_PIX_32BIT			0x00000005
67 
68 /* maps DFA_PIX_* to pixel size in bytes */
69 static const unsigned char pixsize[] = {
70 	1, 2, 2, 2, 4, 4
71 };
72 
73 /* Display timing generator registers */
74 #define DTG_CONTROL		0x1900
75 #define   DTG_CTL_SCREEN_REFRESH	2
76 #define   DTG_CTL_ENABLE		1
77 #define DTG_HORIZ_EXTENT	0x1904
78 #define DTG_HORIZ_DISPLAY	0x1908
79 #define DTG_HSYNC_START		0x190c
80 #define DTG_HSYNC_END		0x1910
81 #define DTG_HSYNC_END_COMP	0x1914
82 #define DTG_VERT_EXTENT		0x1918
83 #define DTG_VERT_DISPLAY	0x191c
84 #define DTG_VSYNC_START		0x1920
85 #define DTG_VSYNC_END		0x1924
86 #define DTG_VERT_SHORT		0x1928
87 
88 /* PLL/RAMDAC registers */
89 #define DISP_CTL		0x402c
90 #define   DISP_CTL_OFF			2
91 #define SYNC_CTL		0x4034
92 #define   SYNC_CTL_SYNC_ON_RGB		1
93 #define   SYNC_CTL_SYNC_OFF		2
94 #define   SYNC_CTL_HSYNC_INV		8
95 #define   SYNC_CTL_VSYNC_INV		0x10
96 #define   SYNC_CTL_HSYNC_OFF		0x20
97 #define   SYNC_CTL_VSYNC_OFF		0x40
98 
99 #define PLL_M			0x4040
100 #define PLL_N			0x4044
101 #define PLL_POSTDIV		0x4048
102 #define PLL_C			0x404c
103 
104 /* Hardware cursor */
105 #define CURSOR_X		0x4078
106 #define CURSOR_Y		0x407c
107 #define CURSOR_HOTSPOT		0x4080
108 #define CURSOR_MODE		0x4084
109 #define   CURSOR_MODE_OFF		0
110 #define   CURSOR_MODE_4BPP		1
111 #define CURSOR_PIXMAP		0x5000
112 #define CURSOR_CMAP		0x7400
113 
114 /* Window attribute table */
115 #define WAT_FMT			0x4100
116 #define   WAT_FMT_24BIT			0
117 #define   WAT_FMT_16BIT_565		1
118 #define   WAT_FMT_16BIT_1555		2
119 #define   WAT_FMT_32BIT			3	/* 0 vs. 3 is a guess */
120 #define   WAT_FMT_8BIT_332		9
121 #define   WAT_FMT_8BIT			0xa
122 #define   WAT_FMT_NO_CMAP		4	/* ORd in to other values */
123 #define WAT_CMAP_OFFSET		0x4104		/* 4-bit value gets << 6 */
124 #define WAT_CTRL		0x4108
125 #define   WAT_CTRL_SEL_B		1	/* select B buffer if 1 */
126 #define   WAT_CTRL_NO_INC		2
127 #define WAT_GAMMA_CTRL		0x410c
128 #define   WAT_GAMMA_DISABLE		1	/* disables gamma cmap */
129 #define WAT_OVL_CTRL		0x430c		/* controls overlay */
130 
131 /* Indexed by DFA_PIX_* values */
132 static const unsigned char watfmt[] = {
133 	WAT_FMT_8BIT, WAT_FMT_16BIT_565, WAT_FMT_16BIT_1555, 0,
134 	WAT_FMT_24BIT, WAT_FMT_32BIT
135 };
136 
137 /* Colormap array; 1k entries of 4 bytes each */
138 #define CMAP			0x6000
139 
140 #define readreg(par, reg)	readl((par)->regs + (reg))
141 #define writereg(par, reg, val)	writel((val), (par)->regs + (reg))
142 
143 struct gxt4500_par {
144 	void __iomem *regs;
145 	int wc_cookie;
146 	int pixfmt;		/* pixel format, see DFA_PIX_* values */
147 
148 	/* PLL parameters */
149 	int refclk_ps;		/* ref clock period in picoseconds */
150 	int pll_m;		/* ref clock divisor */
151 	int pll_n;		/* VCO divisor */
152 	int pll_pd1;		/* first post-divisor */
153 	int pll_pd2;		/* second post-divisor */
154 
155 	u32 pseudo_palette[16];	/* used in color blits */
156 };
157 
158 /* mode requested by user */
159 static char *mode_option;
160 
161 /* default mode: 1280x1024 @ 60 Hz, 8 bpp */
162 static const struct fb_videomode defaultmode = {
163 	.refresh = 60,
164 	.xres = 1280,
165 	.yres = 1024,
166 	.pixclock = 9295,
167 	.left_margin = 248,
168 	.right_margin = 48,
169 	.upper_margin = 38,
170 	.lower_margin = 1,
171 	.hsync_len = 112,
172 	.vsync_len = 3,
173 	.vmode = FB_VMODE_NONINTERLACED
174 };
175 
176 /* List of supported cards */
177 enum gxt_cards {
178 	GXT4500P,
179 	GXT6500P,
180 	GXT4000P,
181 	GXT6000P
182 };
183 
184 /* Card-specific information */
185 static const struct cardinfo {
186 	int	refclk_ps;	/* period of PLL reference clock in ps */
187 	const char *cardname;
188 } cardinfo[] = {
189 	[GXT4500P] = { .refclk_ps = 9259, .cardname = "IBM GXT4500P" },
190 	[GXT6500P] = { .refclk_ps = 9259, .cardname = "IBM GXT6500P" },
191 	[GXT4000P] = { .refclk_ps = 40000, .cardname = "IBM GXT4000P" },
192 	[GXT6000P] = { .refclk_ps = 40000, .cardname = "IBM GXT6000P" },
193 };
194 
195 /*
196  * The refclk and VCO dividers appear to use a linear feedback shift
197  * register, which gets reloaded when it reaches a terminal value, at
198  * which point the divider output is toggled.  Thus one can obtain
199  * whatever divisor is required by putting the appropriate value into
200  * the reload register.  For a divisor of N, one puts the value from
201  * the LFSR sequence that comes N-1 places before the terminal value
202  * into the reload register.
203  */
204 
205 static const unsigned char mdivtab[] = {
206 /* 1 */		      0x3f, 0x00, 0x20, 0x10, 0x28, 0x14, 0x2a, 0x15, 0x0a,
207 /* 10 */	0x25, 0x32, 0x19, 0x0c, 0x26, 0x13, 0x09, 0x04, 0x22, 0x11,
208 /* 20 */	0x08, 0x24, 0x12, 0x29, 0x34, 0x1a, 0x2d, 0x36, 0x1b, 0x0d,
209 /* 30 */	0x06, 0x23, 0x31, 0x38, 0x1c, 0x2e, 0x17, 0x0b, 0x05, 0x02,
210 /* 40 */	0x21, 0x30, 0x18, 0x2c, 0x16, 0x2b, 0x35, 0x3a, 0x1d, 0x0e,
211 /* 50 */	0x27, 0x33, 0x39, 0x3c, 0x1e, 0x2f, 0x37, 0x3b, 0x3d, 0x3e,
212 /* 60 */	0x1f, 0x0f, 0x07, 0x03, 0x01,
213 };
214 
215 static const unsigned char ndivtab[] = {
216 /* 2 */		            0x00, 0x80, 0xc0, 0xe0, 0xf0, 0x78, 0xbc, 0x5e,
217 /* 10 */	0x2f, 0x17, 0x0b, 0x85, 0xc2, 0xe1, 0x70, 0x38, 0x9c, 0x4e,
218 /* 20 */	0xa7, 0xd3, 0xe9, 0xf4, 0xfa, 0xfd, 0xfe, 0x7f, 0xbf, 0xdf,
219 /* 30 */	0xef, 0x77, 0x3b, 0x1d, 0x8e, 0xc7, 0xe3, 0x71, 0xb8, 0xdc,
220 /* 40 */	0x6e, 0xb7, 0x5b, 0x2d, 0x16, 0x8b, 0xc5, 0xe2, 0xf1, 0xf8,
221 /* 50 */	0xfc, 0x7e, 0x3f, 0x9f, 0xcf, 0x67, 0xb3, 0xd9, 0x6c, 0xb6,
222 /* 60 */	0xdb, 0x6d, 0x36, 0x9b, 0x4d, 0x26, 0x13, 0x89, 0xc4, 0x62,
223 /* 70 */	0xb1, 0xd8, 0xec, 0xf6, 0xfb, 0x7d, 0xbe, 0x5f, 0xaf, 0x57,
224 /* 80 */	0x2b, 0x95, 0x4a, 0x25, 0x92, 0x49, 0xa4, 0x52, 0x29, 0x94,
225 /* 90 */	0xca, 0x65, 0xb2, 0x59, 0x2c, 0x96, 0xcb, 0xe5, 0xf2, 0x79,
226 /* 100 */	0x3c, 0x1e, 0x0f, 0x07, 0x83, 0x41, 0x20, 0x90, 0x48, 0x24,
227 /* 110 */	0x12, 0x09, 0x84, 0x42, 0xa1, 0x50, 0x28, 0x14, 0x8a, 0x45,
228 /* 120 */	0xa2, 0xd1, 0xe8, 0x74, 0xba, 0xdd, 0xee, 0xf7, 0x7b, 0x3d,
229 /* 130 */	0x9e, 0x4f, 0x27, 0x93, 0xc9, 0xe4, 0x72, 0x39, 0x1c, 0x0e,
230 /* 140 */	0x87, 0xc3, 0x61, 0x30, 0x18, 0x8c, 0xc6, 0x63, 0x31, 0x98,
231 /* 150 */	0xcc, 0xe6, 0x73, 0xb9, 0x5c, 0x2e, 0x97, 0x4b, 0xa5, 0xd2,
232 /* 160 */	0x69,
233 };
234 
235 static int calc_pll(int period_ps, struct gxt4500_par *par)
236 {
237 	int m, n, pdiv1, pdiv2, postdiv;
238 	int pll_period, best_error, t, intf;
239 
240 	/* only deal with range 5MHz - 300MHz */
241 	if (period_ps < 3333 || period_ps > 200000)
242 		return -1;
243 
244 	best_error = 1000000;
245 	for (pdiv1 = 1; pdiv1 <= 8; ++pdiv1) {
246 		for (pdiv2 = 1; pdiv2 <= pdiv1; ++pdiv2) {
247 			postdiv = pdiv1 * pdiv2;
248 			pll_period = DIV_ROUND_UP(period_ps, postdiv);
249 			/* keep pll in range 350..600 MHz */
250 			if (pll_period < 1666 || pll_period > 2857)
251 				continue;
252 			for (m = 1; m <= 64; ++m) {
253 				intf = m * par->refclk_ps;
254 				if (intf > 500000)
255 					break;
256 				n = intf * postdiv / period_ps;
257 				if (n < 3 || n > 160)
258 					continue;
259 				t = par->refclk_ps * m * postdiv / n;
260 				t -= period_ps;
261 				if (t >= 0 && t < best_error) {
262 					par->pll_m = m;
263 					par->pll_n = n;
264 					par->pll_pd1 = pdiv1;
265 					par->pll_pd2 = pdiv2;
266 					best_error = t;
267 				}
268 			}
269 		}
270 	}
271 	if (best_error == 1000000)
272 		return -1;
273 	return 0;
274 }
275 
276 static int calc_pixclock(struct gxt4500_par *par)
277 {
278 	return par->refclk_ps * par->pll_m * par->pll_pd1 * par->pll_pd2
279 		/ par->pll_n;
280 }
281 
282 static int gxt4500_var_to_par(struct fb_var_screeninfo *var,
283 			      struct gxt4500_par *par)
284 {
285 	if (var->xres + var->xoffset > var->xres_virtual ||
286 	    var->yres + var->yoffset > var->yres_virtual ||
287 	    var->xres_virtual > 4096)
288 		return -EINVAL;
289 	if ((var->vmode & FB_VMODE_MASK) != FB_VMODE_NONINTERLACED)
290 		return -EINVAL;
291 
292 	if (calc_pll(var->pixclock, par) < 0)
293 		return -EINVAL;
294 
295 	switch (var->bits_per_pixel) {
296 	case 32:
297 		if (var->transp.length)
298 			par->pixfmt = DFA_PIX_32BIT;
299 		else
300 			par->pixfmt = DFA_PIX_24BIT;
301 		break;
302 	case 24:
303 		par->pixfmt = DFA_PIX_24BIT;
304 		break;
305 	case 16:
306 		if (var->green.length == 5)
307 			par->pixfmt = DFA_PIX_16BIT_1555;
308 		else
309 			par->pixfmt = DFA_PIX_16BIT_565;
310 		break;
311 	case 8:
312 		par->pixfmt = DFA_PIX_8BIT;
313 		break;
314 	default:
315 		return -EINVAL;
316 	}
317 
318 	return 0;
319 }
320 
321 static const struct fb_bitfield eightbits = {0, 8};
322 static const struct fb_bitfield nobits = {0, 0};
323 
324 static void gxt4500_unpack_pixfmt(struct fb_var_screeninfo *var,
325 				  int pixfmt)
326 {
327 	var->bits_per_pixel = pixsize[pixfmt] * 8;
328 	var->red = eightbits;
329 	var->green = eightbits;
330 	var->blue = eightbits;
331 	var->transp = nobits;
332 
333 	switch (pixfmt) {
334 	case DFA_PIX_16BIT_565:
335 		var->red.length = 5;
336 		var->green.length = 6;
337 		var->blue.length = 5;
338 		break;
339 	case DFA_PIX_16BIT_1555:
340 		var->red.length = 5;
341 		var->green.length = 5;
342 		var->blue.length = 5;
343 		var->transp.length = 1;
344 		break;
345 	case DFA_PIX_32BIT:
346 		var->transp.length = 8;
347 		break;
348 	}
349 	if (pixfmt != DFA_PIX_8BIT) {
350 		var->blue.offset = 0;
351 		var->green.offset = var->blue.length;
352 		var->red.offset = var->green.offset + var->green.length;
353 		if (var->transp.length)
354 			var->transp.offset =
355 				var->red.offset + var->red.length;
356 	}
357 }
358 
359 static int gxt4500_check_var(struct fb_var_screeninfo *var,
360 			     struct fb_info *info)
361 {
362 	struct gxt4500_par par;
363 	int err;
364 
365 	par = *(struct gxt4500_par *)info->par;
366 	err = gxt4500_var_to_par(var, &par);
367 	if (!err) {
368 		var->pixclock = calc_pixclock(&par);
369 		gxt4500_unpack_pixfmt(var, par.pixfmt);
370 	}
371 	return err;
372 }
373 
374 static int gxt4500_set_par(struct fb_info *info)
375 {
376 	struct gxt4500_par *par = info->par;
377 	struct fb_var_screeninfo *var = &info->var;
378 	int err;
379 	u32 ctrlreg, tmp;
380 	unsigned int dfa_ctl, pixfmt, stride;
381 	unsigned int wid_tiles, i;
382 	unsigned int prefetch_pix, htot;
383 	struct gxt4500_par save_par;
384 
385 	save_par = *par;
386 	err = gxt4500_var_to_par(var, par);
387 	if (err) {
388 		*par = save_par;
389 		return err;
390 	}
391 
392 	/* turn off DTG for now */
393 	ctrlreg = readreg(par, DTG_CONTROL);
394 	ctrlreg &= ~(DTG_CTL_ENABLE | DTG_CTL_SCREEN_REFRESH);
395 	writereg(par, DTG_CONTROL, ctrlreg);
396 
397 	/* set PLL registers */
398 	tmp = readreg(par, PLL_C) & ~0x7f;
399 	if (par->pll_n < 38)
400 		tmp |= 0x29;
401 	if (par->pll_n < 69)
402 		tmp |= 0x35;
403 	else if (par->pll_n < 100)
404 		tmp |= 0x76;
405 	else
406 		tmp |= 0x7e;
407 	writereg(par, PLL_C, tmp);
408 	writereg(par, PLL_M, mdivtab[par->pll_m - 1]);
409 	writereg(par, PLL_N, ndivtab[par->pll_n - 2]);
410 	tmp = ((8 - par->pll_pd2) << 3) | (8 - par->pll_pd1);
411 	if (par->pll_pd1 == 8 || par->pll_pd2 == 8) {
412 		/* work around erratum */
413 		writereg(par, PLL_POSTDIV, tmp | 0x9);
414 		udelay(1);
415 	}
416 	writereg(par, PLL_POSTDIV, tmp);
417 	msleep(20);
418 
419 	/* turn off hardware cursor */
420 	writereg(par, CURSOR_MODE, CURSOR_MODE_OFF);
421 
422 	/* reset raster engine */
423 	writereg(par, CTRL_REG0, CR0_RASTER_RESET | (CR0_RASTER_RESET << 16));
424 	udelay(10);
425 	writereg(par, CTRL_REG0, CR0_RASTER_RESET << 16);
426 
427 	/* set display timing generator registers */
428 	htot = var->xres + var->left_margin + var->right_margin +
429 		var->hsync_len;
430 	writereg(par, DTG_HORIZ_EXTENT, htot - 1);
431 	writereg(par, DTG_HORIZ_DISPLAY, var->xres - 1);
432 	writereg(par, DTG_HSYNC_START, var->xres + var->right_margin - 1);
433 	writereg(par, DTG_HSYNC_END,
434 		 var->xres + var->right_margin + var->hsync_len - 1);
435 	writereg(par, DTG_HSYNC_END_COMP,
436 		 var->xres + var->right_margin + var->hsync_len - 1);
437 	writereg(par, DTG_VERT_EXTENT,
438 		 var->yres + var->upper_margin + var->lower_margin +
439 		 var->vsync_len - 1);
440 	writereg(par, DTG_VERT_DISPLAY, var->yres - 1);
441 	writereg(par, DTG_VSYNC_START, var->yres + var->lower_margin - 1);
442 	writereg(par, DTG_VSYNC_END,
443 		 var->yres + var->lower_margin + var->vsync_len - 1);
444 	prefetch_pix = 3300000 / var->pixclock;
445 	if (prefetch_pix >= htot)
446 		prefetch_pix = htot - 1;
447 	writereg(par, DTG_VERT_SHORT, htot - prefetch_pix - 1);
448 	ctrlreg |= DTG_CTL_ENABLE | DTG_CTL_SCREEN_REFRESH;
449 	writereg(par, DTG_CONTROL, ctrlreg);
450 
451 	/* calculate stride in DFA aperture */
452 	if (var->xres_virtual > 2048) {
453 		stride = 4096;
454 		dfa_ctl = DFA_FB_STRIDE_4k;
455 	} else if (var->xres_virtual > 1024) {
456 		stride = 2048;
457 		dfa_ctl = DFA_FB_STRIDE_2k;
458 	} else {
459 		stride = 1024;
460 		dfa_ctl = DFA_FB_STRIDE_1k;
461 	}
462 
463 	/* Set up framebuffer definition */
464 	wid_tiles = (var->xres_virtual + 63) >> 6;
465 
466 	/* XXX add proper FB allocation here someday */
467 	writereg(par, FB_AB_CTRL, FB_CTRL_TYPE | (wid_tiles << 16) | 0);
468 	writereg(par, REFRESH_AB_CTRL, FB_CTRL_TYPE | (wid_tiles << 16) | 0);
469 	writereg(par, FB_CD_CTRL, FB_CTRL_TYPE | (wid_tiles << 16) | 0);
470 	writereg(par, REFRESH_CD_CTRL, FB_CTRL_TYPE | (wid_tiles << 16) | 0);
471 	writereg(par, REFRESH_START, (var->xoffset << 16) | var->yoffset);
472 	writereg(par, REFRESH_SIZE, (var->xres << 16) | var->yres);
473 
474 	/* Set up framebuffer access by CPU */
475 
476 	pixfmt = par->pixfmt;
477 	dfa_ctl |= DFA_FB_ENABLE | pixfmt;
478 	writereg(par, DFA_FB_A, dfa_ctl);
479 
480 	/*
481 	 * Set up window attribute table.
482 	 * We set all WAT entries the same so it doesn't matter what the
483 	 * window ID (WID) plane contains.
484 	 */
485 	for (i = 0; i < 32; ++i) {
486 		writereg(par, WAT_FMT + (i << 4), watfmt[pixfmt]);
487 		writereg(par, WAT_CMAP_OFFSET + (i << 4), 0);
488 		writereg(par, WAT_CTRL + (i << 4), 0);
489 		writereg(par, WAT_GAMMA_CTRL + (i << 4), WAT_GAMMA_DISABLE);
490 	}
491 
492 	/* Set sync polarity etc. */
493 	ctrlreg = readreg(par, SYNC_CTL) &
494 		~(SYNC_CTL_SYNC_ON_RGB | SYNC_CTL_HSYNC_INV |
495 		  SYNC_CTL_VSYNC_INV);
496 	if (var->sync & FB_SYNC_ON_GREEN)
497 		ctrlreg |= SYNC_CTL_SYNC_ON_RGB;
498 	if (!(var->sync & FB_SYNC_HOR_HIGH_ACT))
499 		ctrlreg |= SYNC_CTL_HSYNC_INV;
500 	if (!(var->sync & FB_SYNC_VERT_HIGH_ACT))
501 		ctrlreg |= SYNC_CTL_VSYNC_INV;
502 	writereg(par, SYNC_CTL, ctrlreg);
503 
504 	info->fix.line_length = stride * pixsize[pixfmt];
505 	info->fix.visual = (pixfmt == DFA_PIX_8BIT)? FB_VISUAL_PSEUDOCOLOR:
506 		FB_VISUAL_DIRECTCOLOR;
507 
508 	return 0;
509 }
510 
511 static int gxt4500_setcolreg(unsigned int reg, unsigned int red,
512 			     unsigned int green, unsigned int blue,
513 			     unsigned int transp, struct fb_info *info)
514 {
515 	u32 cmap_entry;
516 	struct gxt4500_par *par = info->par;
517 
518 	if (reg > 1023)
519 		return 1;
520 	cmap_entry = ((transp & 0xff00) << 16) | ((red & 0xff00) << 8) |
521 		(green & 0xff00) | (blue >> 8);
522 	writereg(par, CMAP + reg * 4, cmap_entry);
523 
524 	if (reg < 16 && par->pixfmt != DFA_PIX_8BIT) {
525 		u32 *pal = info->pseudo_palette;
526 		u32 val = reg;
527 		switch (par->pixfmt) {
528 		case DFA_PIX_16BIT_565:
529 			val |= (reg << 11) | (reg << 5);
530 			break;
531 		case DFA_PIX_16BIT_1555:
532 			val |= (reg << 10) | (reg << 5);
533 			break;
534 		case DFA_PIX_32BIT:
535 			val |= (reg << 24);
536 			/* fall through */
537 		case DFA_PIX_24BIT:
538 			val |= (reg << 16) | (reg << 8);
539 			break;
540 		}
541 		pal[reg] = val;
542 	}
543 
544 	return 0;
545 }
546 
547 static int gxt4500_pan_display(struct fb_var_screeninfo *var,
548 			       struct fb_info *info)
549 {
550 	struct gxt4500_par *par = info->par;
551 
552 	if (var->xoffset & 7)
553 		return -EINVAL;
554 	if (var->xoffset + info->var.xres > info->var.xres_virtual ||
555 	    var->yoffset + info->var.yres > info->var.yres_virtual)
556 		return -EINVAL;
557 
558 	writereg(par, REFRESH_START, (var->xoffset << 16) | var->yoffset);
559 	return 0;
560 }
561 
562 static int gxt4500_blank(int blank, struct fb_info *info)
563 {
564 	struct gxt4500_par *par = info->par;
565 	int ctrl, dctl;
566 
567 	ctrl = readreg(par, SYNC_CTL);
568 	ctrl &= ~(SYNC_CTL_SYNC_OFF | SYNC_CTL_HSYNC_OFF | SYNC_CTL_VSYNC_OFF);
569 	dctl = readreg(par, DISP_CTL);
570 	dctl |= DISP_CTL_OFF;
571 	switch (blank) {
572 	case FB_BLANK_UNBLANK:
573 		dctl &= ~DISP_CTL_OFF;
574 		break;
575 	case FB_BLANK_POWERDOWN:
576 		ctrl |= SYNC_CTL_SYNC_OFF;
577 		break;
578 	case FB_BLANK_HSYNC_SUSPEND:
579 		ctrl |= SYNC_CTL_HSYNC_OFF;
580 		break;
581 	case FB_BLANK_VSYNC_SUSPEND:
582 		ctrl |= SYNC_CTL_VSYNC_OFF;
583 		break;
584 	default: ;
585 	}
586 	writereg(par, SYNC_CTL, ctrl);
587 	writereg(par, DISP_CTL, dctl);
588 
589 	return 0;
590 }
591 
592 static const struct fb_fix_screeninfo gxt4500_fix = {
593 	.id = "IBM GXT4500P",
594 	.type = FB_TYPE_PACKED_PIXELS,
595 	.visual = FB_VISUAL_PSEUDOCOLOR,
596 	.xpanstep = 8,
597 	.ypanstep = 1,
598 	.mmio_len = 0x20000,
599 };
600 
601 static struct fb_ops gxt4500_ops = {
602 	.owner = THIS_MODULE,
603 	.fb_check_var = gxt4500_check_var,
604 	.fb_set_par = gxt4500_set_par,
605 	.fb_setcolreg = gxt4500_setcolreg,
606 	.fb_pan_display = gxt4500_pan_display,
607 	.fb_blank = gxt4500_blank,
608 	.fb_fillrect = cfb_fillrect,
609 	.fb_copyarea = cfb_copyarea,
610 	.fb_imageblit = cfb_imageblit,
611 };
612 
613 /* PCI functions */
614 static int gxt4500_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
615 {
616 	int err;
617 	unsigned long reg_phys, fb_phys;
618 	struct gxt4500_par *par;
619 	struct fb_info *info;
620 	struct fb_var_screeninfo var;
621 	enum gxt_cards cardtype;
622 
623 	err = pci_enable_device(pdev);
624 	if (err) {
625 		dev_err(&pdev->dev, "gxt4500: cannot enable PCI device: %d\n",
626 			err);
627 		return err;
628 	}
629 
630 	reg_phys = pci_resource_start(pdev, 0);
631 	if (!request_mem_region(reg_phys, pci_resource_len(pdev, 0),
632 				"gxt4500 regs")) {
633 		dev_err(&pdev->dev, "gxt4500: cannot get registers\n");
634 		goto err_nodev;
635 	}
636 
637 	fb_phys = pci_resource_start(pdev, 1);
638 	if (!request_mem_region(fb_phys, pci_resource_len(pdev, 1),
639 				"gxt4500 FB")) {
640 		dev_err(&pdev->dev, "gxt4500: cannot get framebuffer\n");
641 		goto err_free_regs;
642 	}
643 
644 	info = framebuffer_alloc(sizeof(struct gxt4500_par), &pdev->dev);
645 	if (!info) {
646 		dev_err(&pdev->dev, "gxt4500: cannot alloc FB info record\n");
647 		goto err_free_fb;
648 	}
649 	par = info->par;
650 	cardtype = ent->driver_data;
651 	par->refclk_ps = cardinfo[cardtype].refclk_ps;
652 	info->fix = gxt4500_fix;
653 	strlcpy(info->fix.id, cardinfo[cardtype].cardname,
654 		sizeof(info->fix.id));
655 	info->pseudo_palette = par->pseudo_palette;
656 
657 	info->fix.mmio_start = reg_phys;
658 	par->regs = pci_ioremap_bar(pdev, 0);
659 	if (!par->regs) {
660 		dev_err(&pdev->dev, "gxt4500: cannot map registers\n");
661 		goto err_free_all;
662 	}
663 
664 	info->fix.smem_start = fb_phys;
665 	info->fix.smem_len = pci_resource_len(pdev, 1);
666 	info->screen_base = pci_ioremap_wc_bar(pdev, 1);
667 	if (!info->screen_base) {
668 		dev_err(&pdev->dev, "gxt4500: cannot map framebuffer\n");
669 		goto err_unmap_regs;
670 	}
671 
672 	pci_set_drvdata(pdev, info);
673 
674 	par->wc_cookie = arch_phys_wc_add(info->fix.smem_start,
675 					  info->fix.smem_len);
676 
677 #ifdef __BIG_ENDIAN
678 	/* Set byte-swapping for DFA aperture for all pixel sizes */
679 	pci_write_config_dword(pdev, CFG_ENDIAN0, 0x333300);
680 #else /* __LITTLE_ENDIAN */
681 	/* not sure what this means but fgl23 driver does that */
682 	pci_write_config_dword(pdev, CFG_ENDIAN0, 0x2300);
683 /*	pci_write_config_dword(pdev, CFG_ENDIAN0 + 4, 0x400000);*/
684 	pci_write_config_dword(pdev, CFG_ENDIAN0 + 8, 0x98530000);
685 #endif
686 
687 	info->fbops = &gxt4500_ops;
688 	info->flags = FBINFO_FLAG_DEFAULT | FBINFO_HWACCEL_XPAN |
689 					    FBINFO_HWACCEL_YPAN;
690 
691 	err = fb_alloc_cmap(&info->cmap, 256, 0);
692 	if (err) {
693 		dev_err(&pdev->dev, "gxt4500: cannot allocate cmap\n");
694 		goto err_unmap_all;
695 	}
696 
697 	gxt4500_blank(FB_BLANK_UNBLANK, info);
698 
699 	if (!fb_find_mode(&var, info, mode_option, NULL, 0, &defaultmode, 8)) {
700 		dev_err(&pdev->dev, "gxt4500: cannot find valid video mode\n");
701 		goto err_free_cmap;
702 	}
703 	info->var = var;
704 	if (gxt4500_set_par(info)) {
705 		printk(KERN_ERR "gxt4500: cannot set video mode\n");
706 		goto err_free_cmap;
707 	}
708 
709 	if (register_framebuffer(info) < 0) {
710 		dev_err(&pdev->dev, "gxt4500: cannot register framebuffer\n");
711 		goto err_free_cmap;
712 	}
713 	fb_info(info, "%s frame buffer device\n", info->fix.id);
714 
715 	return 0;
716 
717  err_free_cmap:
718 	fb_dealloc_cmap(&info->cmap);
719  err_unmap_all:
720 	iounmap(info->screen_base);
721  err_unmap_regs:
722 	iounmap(par->regs);
723  err_free_all:
724 	framebuffer_release(info);
725  err_free_fb:
726 	release_mem_region(fb_phys, pci_resource_len(pdev, 1));
727  err_free_regs:
728 	release_mem_region(reg_phys, pci_resource_len(pdev, 0));
729  err_nodev:
730 	return -ENODEV;
731 }
732 
733 static void gxt4500_remove(struct pci_dev *pdev)
734 {
735 	struct fb_info *info = pci_get_drvdata(pdev);
736 	struct gxt4500_par *par;
737 
738 	if (!info)
739 		return;
740 	par = info->par;
741 	unregister_framebuffer(info);
742 	arch_phys_wc_del(par->wc_cookie);
743 	fb_dealloc_cmap(&info->cmap);
744 	iounmap(par->regs);
745 	iounmap(info->screen_base);
746 	release_mem_region(pci_resource_start(pdev, 0),
747 			   pci_resource_len(pdev, 0));
748 	release_mem_region(pci_resource_start(pdev, 1),
749 			   pci_resource_len(pdev, 1));
750 	framebuffer_release(info);
751 }
752 
753 /* supported chipsets */
754 static const struct pci_device_id gxt4500_pci_tbl[] = {
755 	{ PCI_DEVICE(PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_GXT4500P),
756 	  .driver_data = GXT4500P },
757 	{ PCI_DEVICE(PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_GXT6500P),
758 	  .driver_data = GXT6500P },
759 	{ PCI_DEVICE(PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_GXT4000P),
760 	  .driver_data = GXT4000P },
761 	{ PCI_DEVICE(PCI_VENDOR_ID_IBM, PCI_DEVICE_ID_IBM_GXT6000P),
762 	  .driver_data = GXT6000P },
763 	{ 0 }
764 };
765 
766 MODULE_DEVICE_TABLE(pci, gxt4500_pci_tbl);
767 
768 static struct pci_driver gxt4500_driver = {
769 	.name = "gxt4500",
770 	.id_table = gxt4500_pci_tbl,
771 	.probe = gxt4500_probe,
772 	.remove = gxt4500_remove,
773 };
774 
775 static int gxt4500_init(void)
776 {
777 #ifndef MODULE
778 	if (fb_get_options("gxt4500", &mode_option))
779 		return -ENODEV;
780 #endif
781 
782 	return pci_register_driver(&gxt4500_driver);
783 }
784 module_init(gxt4500_init);
785 
786 static void __exit gxt4500_exit(void)
787 {
788 	pci_unregister_driver(&gxt4500_driver);
789 }
790 module_exit(gxt4500_exit);
791 
792 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
793 MODULE_DESCRIPTION("FBDev driver for IBM GXT4500P/6500P and GXT4000P/6000P");
794 MODULE_LICENSE("GPL");
795 module_param(mode_option, charp, 0);
796 MODULE_PARM_DESC(mode_option, "Specify resolution as \"<xres>x<yres>[-<bpp>][@<refresh>]\"");
797