xref: /openbmc/linux/arch/arm/mach-sa1100/assabet.c (revision e7bae9bb)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/arch/arm/mach-sa1100/assabet.c
4  *
5  * Author: Nicolas Pitre
6  *
7  * This file contains all Assabet-specific tweaks.
8  */
9 #include <linux/init.h>
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/errno.h>
13 #include <linux/gpio/gpio-reg.h>
14 #include <linux/gpio/machine.h>
15 #include <linux/gpio_keys.h>
16 #include <linux/ioport.h>
17 #include <linux/platform_data/sa11x0-serial.h>
18 #include <linux/regulator/fixed.h>
19 #include <linux/regulator/machine.h>
20 #include <linux/serial_core.h>
21 #include <linux/platform_device.h>
22 #include <linux/mfd/ucb1x00.h>
23 #include <linux/mtd/mtd.h>
24 #include <linux/mtd/partitions.h>
25 #include <linux/delay.h>
26 #include <linux/mm.h>
27 #include <linux/leds.h>
28 #include <linux/slab.h>
29 
30 #include <video/sa1100fb.h>
31 
32 #include <mach/hardware.h>
33 #include <asm/mach-types.h>
34 #include <asm/setup.h>
35 #include <asm/page.h>
36 #include <asm/pgtable-hwdef.h>
37 #include <asm/tlbflush.h>
38 
39 #include <asm/mach/arch.h>
40 #include <asm/mach/flash.h>
41 #include <linux/platform_data/irda-sa11x0.h>
42 #include <asm/mach/map.h>
43 #include <mach/assabet.h>
44 #include <linux/platform_data/mfd-mcp-sa11x0.h>
45 #include <mach/irqs.h>
46 
47 #include "generic.h"
48 
49 #define ASSABET_BCR_DB1110 \
50 	(ASSABET_BCR_SPK_OFF    | \
51 	 ASSABET_BCR_LED_GREEN  | ASSABET_BCR_LED_RED   | \
52 	 ASSABET_BCR_RS232EN    | ASSABET_BCR_LCD_12RGB | \
53 	 ASSABET_BCR_IRDA_MD0)
54 
55 #define ASSABET_BCR_DB1111 \
56 	(ASSABET_BCR_SPK_OFF    | \
57 	 ASSABET_BCR_LED_GREEN  | ASSABET_BCR_LED_RED   | \
58 	 ASSABET_BCR_RS232EN    | ASSABET_BCR_LCD_12RGB | \
59 	 ASSABET_BCR_CF_BUS_OFF | ASSABET_BCR_STEREO_LB | \
60 	 ASSABET_BCR_IRDA_MD0   | ASSABET_BCR_CF_RST)
61 
62 unsigned long SCR_value = ASSABET_SCR_INIT;
63 EXPORT_SYMBOL(SCR_value);
64 
65 static struct gpio_chip *assabet_bcr_gc;
66 
67 static const char *assabet_names[] = {
68 	"cf_pwr", "cf_gfx_reset", "nsoft_reset", "irda_fsel",
69 	"irda_md0", "irda_md1", "stereo_loopback", "ncf_bus_on",
70 	"audio_pwr_on", "light_pwr_on", "lcd16data", "lcd_pwr_on",
71 	"rs232_on", "nred_led", "ngreen_led", "vib_on",
72 	"com_dtr", "com_rts", "radio_wake_mod", "i2c_enab",
73 	"tvir_enab", "qmute", "radio_pwr_on", "spkr_off",
74 	"rs232_valid", "com_dcd", "com_cts", "com_dsr",
75 	"radio_cts", "radio_dsr", "radio_dcd", "radio_ri",
76 };
77 
78 /* The old deprecated interface */
79 void ASSABET_BCR_frob(unsigned int mask, unsigned int val)
80 {
81 	unsigned long m = mask, v = val;
82 
83 	assabet_bcr_gc->set_multiple(assabet_bcr_gc, &m, &v);
84 }
85 EXPORT_SYMBOL(ASSABET_BCR_frob);
86 
87 static int __init assabet_init_gpio(void __iomem *reg, u32 def_val)
88 {
89 	struct gpio_chip *gc;
90 
91 	writel_relaxed(def_val, reg);
92 
93 	gc = gpio_reg_init(NULL, reg, -1, 32, "assabet", 0xff000000, def_val,
94 			   assabet_names, NULL, NULL);
95 
96 	if (IS_ERR(gc))
97 		return PTR_ERR(gc);
98 
99 	assabet_bcr_gc = gc;
100 
101 	return gc->base;
102 }
103 
104 /*
105  * The codec reset goes to three devices, so we need to release
106  * the rest when any one of these requests it.  However, that
107  * causes the ADV7171 to consume around 100mA - more than half
108  * the LCD-blanked power.
109  *
110  * With the ADV7171, LCD and backlight enabled, we go over
111  * budget on the MAX846 Li-Ion charger, and if no Li-Ion battery
112  * is connected, the Assabet crashes.
113  */
114 #define RST_UCB1X00 (1 << 0)
115 #define RST_UDA1341 (1 << 1)
116 #define RST_ADV7171 (1 << 2)
117 
118 #define SDA GPIO_GPIO(15)
119 #define SCK GPIO_GPIO(18)
120 #define MOD GPIO_GPIO(17)
121 
122 static void adv7171_start(void)
123 {
124 	GPSR = SCK;
125 	udelay(1);
126 	GPSR = SDA;
127 	udelay(2);
128 	GPCR = SDA;
129 }
130 
131 static void adv7171_stop(void)
132 {
133 	GPSR = SCK;
134 	udelay(2);
135 	GPSR = SDA;
136 	udelay(1);
137 }
138 
139 static void adv7171_send(unsigned byte)
140 {
141 	unsigned i;
142 
143 	for (i = 0; i < 8; i++, byte <<= 1) {
144 		GPCR = SCK;
145 		udelay(1);
146 		if (byte & 0x80)
147 			GPSR = SDA;
148 		else
149 			GPCR = SDA;
150 		udelay(1);
151 		GPSR = SCK;
152 		udelay(1);
153 	}
154 	GPCR = SCK;
155 	udelay(1);
156 	GPSR = SDA;
157 	udelay(1);
158 	GPDR &= ~SDA;
159 	GPSR = SCK;
160 	udelay(1);
161 	if (GPLR & SDA)
162 		printk(KERN_WARNING "No ACK from ADV7171\n");
163 	udelay(1);
164 	GPCR = SCK | SDA;
165 	udelay(1);
166 	GPDR |= SDA;
167 	udelay(1);
168 }
169 
170 static void adv7171_write(unsigned reg, unsigned val)
171 {
172 	unsigned gpdr = GPDR;
173 	unsigned gplr = GPLR;
174 
175 	ASSABET_BCR_frob(ASSABET_BCR_AUDIO_ON, ASSABET_BCR_AUDIO_ON);
176 	udelay(100);
177 
178 	GPCR = SDA | SCK | MOD; /* clear L3 mode to ensure UDA1341 doesn't respond */
179 	GPDR = (GPDR | SCK | MOD) & ~SDA;
180 	udelay(10);
181 	if (!(GPLR & SDA))
182 		printk(KERN_WARNING "Something dragging SDA down?\n");
183 	GPDR |= SDA;
184 
185 	adv7171_start();
186 	adv7171_send(0x54);
187 	adv7171_send(reg);
188 	adv7171_send(val);
189 	adv7171_stop();
190 
191 	/* Restore GPIO state for L3 bus */
192 	GPSR = gplr & (SDA | SCK | MOD);
193 	GPCR = (~gplr) & (SDA | SCK | MOD);
194 	GPDR = gpdr;
195 }
196 
197 static void adv7171_sleep(void)
198 {
199 	/* Put the ADV7171 into sleep mode */
200 	adv7171_write(0x04, 0x40);
201 }
202 
203 static unsigned codec_nreset;
204 
205 static void assabet_codec_reset(unsigned mask, int set)
206 {
207 	unsigned long flags;
208 	bool old;
209 
210 	local_irq_save(flags);
211 	old = !codec_nreset;
212 	if (set)
213 		codec_nreset &= ~mask;
214 	else
215 		codec_nreset |= mask;
216 
217 	if (old != !codec_nreset) {
218 		if (codec_nreset) {
219 			ASSABET_BCR_set(ASSABET_BCR_NCODEC_RST);
220 			adv7171_sleep();
221 		} else {
222 			ASSABET_BCR_clear(ASSABET_BCR_NCODEC_RST);
223 		}
224 	}
225 	local_irq_restore(flags);
226 }
227 
228 static void assabet_ucb1x00_reset(enum ucb1x00_reset state)
229 {
230 	int set = state == UCB_RST_REMOVE || state == UCB_RST_SUSPEND ||
231 		state == UCB_RST_PROBE_FAIL;
232 	assabet_codec_reset(RST_UCB1X00, set);
233 }
234 
235 void assabet_uda1341_reset(int set)
236 {
237 	assabet_codec_reset(RST_UDA1341, set);
238 }
239 EXPORT_SYMBOL(assabet_uda1341_reset);
240 
241 
242 /*
243  * Assabet flash support code.
244  */
245 
246 #ifdef ASSABET_REV_4
247 /*
248  * Phase 4 Assabet has two 28F160B3 flash parts in bank 0:
249  */
250 static struct mtd_partition assabet_partitions[] = {
251 	{
252 		.name		= "bootloader",
253 		.size		= 0x00020000,
254 		.offset		= 0,
255 		.mask_flags	= MTD_WRITEABLE,
256 	}, {
257 		.name		= "bootloader params",
258 		.size		= 0x00020000,
259 		.offset		= MTDPART_OFS_APPEND,
260 		.mask_flags	= MTD_WRITEABLE,
261 	}, {
262 		.name		= "jffs",
263 		.size		= MTDPART_SIZ_FULL,
264 		.offset		= MTDPART_OFS_APPEND,
265 	}
266 };
267 #else
268 /*
269  * Phase 5 Assabet has two 28F128J3A flash parts in bank 0:
270  */
271 static struct mtd_partition assabet_partitions[] = {
272 	{
273 		.name		= "bootloader",
274 		.size		= 0x00040000,
275 		.offset		= 0,
276 		.mask_flags	= MTD_WRITEABLE,
277 	}, {
278 		.name		= "bootloader params",
279 		.size		= 0x00040000,
280 		.offset		= MTDPART_OFS_APPEND,
281 		.mask_flags	= MTD_WRITEABLE,
282 	}, {
283 		.name		= "jffs",
284 		.size		= MTDPART_SIZ_FULL,
285 		.offset		= MTDPART_OFS_APPEND,
286 	}
287 };
288 #endif
289 
290 static struct flash_platform_data assabet_flash_data = {
291 	.map_name	= "cfi_probe",
292 	.parts		= assabet_partitions,
293 	.nr_parts	= ARRAY_SIZE(assabet_partitions),
294 };
295 
296 static struct resource assabet_flash_resources[] = {
297 	DEFINE_RES_MEM(SA1100_CS0_PHYS, SZ_32M),
298 	DEFINE_RES_MEM(SA1100_CS1_PHYS, SZ_32M),
299 };
300 
301 
302 /*
303  * Assabet IrDA support code.
304  */
305 
306 static int assabet_irda_set_power(struct device *dev, unsigned int state)
307 {
308 	static unsigned int bcr_state[4] = {
309 		ASSABET_BCR_IRDA_MD0,
310 		ASSABET_BCR_IRDA_MD1|ASSABET_BCR_IRDA_MD0,
311 		ASSABET_BCR_IRDA_MD1,
312 		0
313 	};
314 
315 	if (state < 4)
316 		ASSABET_BCR_frob(ASSABET_BCR_IRDA_MD1 | ASSABET_BCR_IRDA_MD0,
317 				 bcr_state[state]);
318 	return 0;
319 }
320 
321 static void assabet_irda_set_speed(struct device *dev, unsigned int speed)
322 {
323 	if (speed < 4000000)
324 		ASSABET_BCR_clear(ASSABET_BCR_IRDA_FSEL);
325 	else
326 		ASSABET_BCR_set(ASSABET_BCR_IRDA_FSEL);
327 }
328 
329 static struct irda_platform_data assabet_irda_data = {
330 	.set_power	= assabet_irda_set_power,
331 	.set_speed	= assabet_irda_set_speed,
332 };
333 
334 static struct ucb1x00_plat_data assabet_ucb1x00_data = {
335 	.reset		= assabet_ucb1x00_reset,
336 	.gpio_base	= -1,
337 	.can_wakeup	= 1,
338 };
339 
340 static struct mcp_plat_data assabet_mcp_data = {
341 	.mccr0		= MCCR0_ADM,
342 	.sclk_rate	= 11981000,
343 	.codec_pdata	= &assabet_ucb1x00_data,
344 };
345 
346 static void assabet_lcd_set_visual(u32 visual)
347 {
348 	u_int is_true_color = visual == FB_VISUAL_TRUECOLOR;
349 
350 	if (machine_is_assabet()) {
351 #if 1		// phase 4 or newer Assabet's
352 		if (is_true_color)
353 			ASSABET_BCR_set(ASSABET_BCR_LCD_12RGB);
354 		else
355 			ASSABET_BCR_clear(ASSABET_BCR_LCD_12RGB);
356 #else
357 		// older Assabet's
358 		if (is_true_color)
359 			ASSABET_BCR_clear(ASSABET_BCR_LCD_12RGB);
360 		else
361 			ASSABET_BCR_set(ASSABET_BCR_LCD_12RGB);
362 #endif
363 	}
364 }
365 
366 #ifndef ASSABET_PAL_VIDEO
367 static void assabet_lcd_backlight_power(int on)
368 {
369 	if (on)
370 		ASSABET_BCR_set(ASSABET_BCR_LIGHT_ON);
371 	else
372 		ASSABET_BCR_clear(ASSABET_BCR_LIGHT_ON);
373 }
374 
375 /*
376  * Turn on/off the backlight.  When turning the backlight on, we wait
377  * 500us after turning it on so we don't cause the supplies to droop
378  * when we enable the LCD controller (and cause a hard reset.)
379  */
380 static void assabet_lcd_power(int on)
381 {
382 	if (on) {
383 		ASSABET_BCR_set(ASSABET_BCR_LCD_ON);
384 		udelay(500);
385 	} else
386 		ASSABET_BCR_clear(ASSABET_BCR_LCD_ON);
387 }
388 
389 /*
390  * The assabet uses a sharp LQ039Q2DS54 LCD module.  It is actually
391  * takes an RGB666 signal, but we provide it with an RGB565 signal
392  * instead (def_rgb_16).
393  */
394 static struct sa1100fb_mach_info lq039q2ds54_info = {
395 	.pixclock	= 171521,	.bpp		= 16,
396 	.xres		= 320,		.yres		= 240,
397 
398 	.hsync_len	= 5,		.vsync_len	= 1,
399 	.left_margin	= 61,		.upper_margin	= 3,
400 	.right_margin	= 9,		.lower_margin	= 0,
401 
402 	.sync		= FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
403 
404 	.lccr0		= LCCR0_Color | LCCR0_Sngl | LCCR0_Act,
405 	.lccr3		= LCCR3_OutEnH | LCCR3_PixRsEdg | LCCR3_ACBsDiv(2),
406 
407 	.backlight_power = assabet_lcd_backlight_power,
408 	.lcd_power = assabet_lcd_power,
409 	.set_visual = assabet_lcd_set_visual,
410 };
411 #else
412 static void assabet_pal_backlight_power(int on)
413 {
414 	ASSABET_BCR_clear(ASSABET_BCR_LIGHT_ON);
415 }
416 
417 static void assabet_pal_power(int on)
418 {
419 	ASSABET_BCR_clear(ASSABET_BCR_LCD_ON);
420 }
421 
422 static struct sa1100fb_mach_info pal_info = {
423 	.pixclock	= 67797,	.bpp		= 16,
424 	.xres		= 640,		.yres		= 512,
425 
426 	.hsync_len	= 64,		.vsync_len	= 6,
427 	.left_margin	= 125,		.upper_margin	= 70,
428 	.right_margin	= 115,		.lower_margin	= 36,
429 
430 	.lccr0		= LCCR0_Color | LCCR0_Sngl | LCCR0_Act,
431 	.lccr3		= LCCR3_OutEnH | LCCR3_PixRsEdg | LCCR3_ACBsDiv(512),
432 
433 	.backlight_power = assabet_pal_backlight_power,
434 	.lcd_power = assabet_pal_power,
435 	.set_visual = assabet_lcd_set_visual,
436 };
437 #endif
438 
439 #ifdef CONFIG_ASSABET_NEPONSET
440 static struct resource neponset_resources[] = {
441 	DEFINE_RES_MEM(0x10000000, 0x08000000),
442 	DEFINE_RES_MEM(0x18000000, 0x04000000),
443 	DEFINE_RES_MEM(0x40000000, SZ_8K),
444 	DEFINE_RES_IRQ(IRQ_GPIO25),
445 };
446 #endif
447 
448 static struct gpiod_lookup_table assabet_cf_gpio_table = {
449 	.dev_id = "sa11x0-pcmcia.1",
450 	.table = {
451 		GPIO_LOOKUP("gpio", 21, "ready", GPIO_ACTIVE_HIGH),
452 		GPIO_LOOKUP("gpio", 22, "detect", GPIO_ACTIVE_LOW),
453 		GPIO_LOOKUP("gpio", 24, "bvd2", GPIO_ACTIVE_HIGH),
454 		GPIO_LOOKUP("gpio", 25, "bvd1", GPIO_ACTIVE_HIGH),
455 		GPIO_LOOKUP("assabet", 1, "reset", GPIO_ACTIVE_HIGH),
456 		GPIO_LOOKUP("assabet", 7, "bus-enable", GPIO_ACTIVE_LOW),
457 		{ },
458 	},
459 };
460 
461 static struct regulator_consumer_supply assabet_cf_vcc_consumers[] = {
462 	REGULATOR_SUPPLY("vcc", "sa11x0-pcmcia.1"),
463 };
464 
465 static struct fixed_voltage_config assabet_cf_vcc_pdata __initdata = {
466 	.supply_name = "cf-power",
467 	.microvolts = 3300000,
468 };
469 
470 static struct gpiod_lookup_table assabet_cf_vcc_gpio_table = {
471 	.dev_id = "reg-fixed-voltage.0",
472 	.table = {
473 		GPIO_LOOKUP("assabet", 0, NULL, GPIO_ACTIVE_HIGH),
474 		{ },
475 	},
476 };
477 
478 static struct gpio_led assabet_leds[] __initdata = {
479 	{
480 		.name = "assabet:red",
481 		.default_trigger = "cpu0",
482 		.active_low = 1,
483 		.default_state = LEDS_GPIO_DEFSTATE_KEEP,
484 	}, {
485 		.name = "assabet:green",
486 		.default_trigger = "heartbeat",
487 		.active_low = 1,
488 		.default_state = LEDS_GPIO_DEFSTATE_KEEP,
489 	},
490 };
491 
492 static const struct gpio_led_platform_data assabet_leds_pdata __initconst = {
493 	.num_leds = ARRAY_SIZE(assabet_leds),
494 	.leds = assabet_leds,
495 };
496 
497 static struct gpio_keys_button assabet_keys_buttons[] = {
498 	{
499 		.gpio = 0,
500 		.irq = IRQ_GPIO0,
501 		.desc = "gpio0",
502 		.wakeup = 1,
503 		.can_disable = 1,
504 		.debounce_interval = 5,
505 	}, {
506 		.gpio = 1,
507 		.irq = IRQ_GPIO1,
508 		.desc = "gpio1",
509 		.wakeup = 1,
510 		.can_disable = 1,
511 		.debounce_interval = 5,
512 	},
513 };
514 
515 static const struct gpio_keys_platform_data assabet_keys_pdata = {
516 	.buttons = assabet_keys_buttons,
517 	.nbuttons = ARRAY_SIZE(assabet_keys_buttons),
518 	.rep = 0,
519 };
520 
521 static struct gpiod_lookup_table assabet_uart1_gpio_table = {
522 	.dev_id = "sa11x0-uart.1",
523 	.table = {
524 		GPIO_LOOKUP("assabet", 16, "dtr", GPIO_ACTIVE_LOW),
525 		GPIO_LOOKUP("assabet", 17, "rts", GPIO_ACTIVE_LOW),
526 		GPIO_LOOKUP("assabet", 25, "dcd", GPIO_ACTIVE_LOW),
527 		GPIO_LOOKUP("assabet", 26, "cts", GPIO_ACTIVE_LOW),
528 		GPIO_LOOKUP("assabet", 27, "dsr", GPIO_ACTIVE_LOW),
529 		{ },
530 	},
531 };
532 
533 static struct gpiod_lookup_table assabet_uart3_gpio_table = {
534 	.dev_id = "sa11x0-uart.3",
535 	.table = {
536 		GPIO_LOOKUP("assabet", 28, "cts", GPIO_ACTIVE_LOW),
537 		GPIO_LOOKUP("assabet", 29, "dsr", GPIO_ACTIVE_LOW),
538 		GPIO_LOOKUP("assabet", 30, "dcd", GPIO_ACTIVE_LOW),
539 		GPIO_LOOKUP("assabet", 31, "rng", GPIO_ACTIVE_LOW),
540 		{ },
541 	},
542 };
543 
544 static void __init assabet_init(void)
545 {
546 	/*
547 	 * Ensure that the power supply is in "high power" mode.
548 	 */
549 	GPSR = GPIO_GPIO16;
550 	GPDR |= GPIO_GPIO16;
551 
552 	/*
553 	 * Ensure that these pins are set as outputs and are driving
554 	 * logic 0.  This ensures that we won't inadvertently toggle
555 	 * the WS latch in the CPLD, and we don't float causing
556 	 * excessive power drain.  --rmk
557 	 */
558 	GPCR = GPIO_SSP_TXD | GPIO_SSP_SCLK | GPIO_SSP_SFRM;
559 	GPDR |= GPIO_SSP_TXD | GPIO_SSP_SCLK | GPIO_SSP_SFRM;
560 
561 	/*
562 	 * Also set GPIO27 as an output; this is used to clock UART3
563 	 * via the FPGA and as otherwise has no pullups or pulldowns,
564 	 * so stop it floating.
565 	 */
566 	GPCR = GPIO_GPIO27;
567 	GPDR |= GPIO_GPIO27;
568 
569 	/*
570 	 * Set up registers for sleep mode.
571 	 */
572 	PWER = PWER_GPIO0;
573 	PGSR = 0;
574 	PCFR = 0;
575 	PSDR = 0;
576 	PPDR |= PPC_TXD3 | PPC_TXD1;
577 	PPSR |= PPC_TXD3 | PPC_TXD1;
578 
579 	sa11x0_ppc_configure_mcp();
580 
581 	if (machine_has_neponset()) {
582 #ifndef CONFIG_ASSABET_NEPONSET
583 		printk( "Warning: Neponset detected but full support "
584 			"hasn't been configured in the kernel\n" );
585 #else
586 		platform_device_register_simple("neponset", 0,
587 			neponset_resources, ARRAY_SIZE(neponset_resources));
588 #endif
589 	} else {
590 		gpiod_add_lookup_table(&assabet_uart1_gpio_table);
591 		gpiod_add_lookup_table(&assabet_uart3_gpio_table);
592 		gpiod_add_lookup_table(&assabet_cf_vcc_gpio_table);
593 
594 		sa11x0_register_fixed_regulator(0, &assabet_cf_vcc_pdata,
595 					assabet_cf_vcc_consumers,
596 					ARRAY_SIZE(assabet_cf_vcc_consumers),
597 					true);
598 
599 	}
600 
601 	platform_device_register_resndata(NULL, "gpio-keys", 0,
602 					  NULL, 0,
603 					  &assabet_keys_pdata,
604 					  sizeof(assabet_keys_pdata));
605 
606 	gpio_led_register_device(-1, &assabet_leds_pdata);
607 
608 #ifndef ASSABET_PAL_VIDEO
609 	sa11x0_register_lcd(&lq039q2ds54_info);
610 #else
611 	sa11x0_register_lcd(&pal_video);
612 #endif
613 	sa11x0_register_mtd(&assabet_flash_data, assabet_flash_resources,
614 			    ARRAY_SIZE(assabet_flash_resources));
615 	sa11x0_register_irda(&assabet_irda_data);
616 	sa11x0_register_mcp(&assabet_mcp_data);
617 
618 	if (!machine_has_neponset())
619 		sa11x0_register_pcmcia(1, &assabet_cf_gpio_table);
620 }
621 
622 /*
623  * On Assabet, we must probe for the Neponset board _before_
624  * paging_init() has occurred to actually determine the amount
625  * of RAM available.  To do so, we map the appropriate IO section
626  * in the page table here in order to access GPIO registers.
627  */
628 static void __init map_sa1100_gpio_regs( void )
629 {
630 	unsigned long phys = __PREG(GPLR) & PMD_MASK;
631 	unsigned long virt = (unsigned long)io_p2v(phys);
632 	int prot = PMD_TYPE_SECT | PMD_SECT_AP_WRITE | PMD_DOMAIN(DOMAIN_IO);
633 	pmd_t *pmd;
634 
635 	pmd = pmd_off_k(virt);
636 	*pmd = __pmd(phys | prot);
637 	flush_pmd_entry(pmd);
638 }
639 
640 /*
641  * Read System Configuration "Register"
642  * (taken from "Intel StrongARM SA-1110 Microprocessor Development Board
643  * User's Guide", section 4.4.1)
644  *
645  * This same scan is performed in arch/arm/boot/compressed/head-sa1100.S
646  * to set up the serial port for decompression status messages. We
647  * repeat it here because the kernel may not be loaded as a zImage, and
648  * also because it's a hassle to communicate the SCR value to the kernel
649  * from the decompressor.
650  *
651  * Note that IRQs are guaranteed to be disabled.
652  */
653 static void __init get_assabet_scr(void)
654 {
655 	unsigned long scr, i;
656 
657 	GPDR |= 0x3fc;			/* Configure GPIO 9:2 as outputs */
658 	GPSR = 0x3fc;			/* Write 0xFF to GPIO 9:2 */
659 	GPDR &= ~(0x3fc);		/* Configure GPIO 9:2 as inputs */
660 	for(i = 100; i--; )		/* Read GPIO 9:2 */
661 		scr = GPLR;
662 	GPDR |= 0x3fc;			/*  restore correct pin direction */
663 	scr &= 0x3fc;			/* save as system configuration byte. */
664 	SCR_value = scr;
665 }
666 
667 static void __init
668 fixup_assabet(struct tag *tags, char **cmdline)
669 {
670 	/* This must be done before any call to machine_has_neponset() */
671 	map_sa1100_gpio_regs();
672 	get_assabet_scr();
673 
674 	if (machine_has_neponset())
675 		printk("Neponset expansion board detected\n");
676 }
677 
678 
679 static void assabet_uart_pm(struct uart_port *port, u_int state, u_int oldstate)
680 {
681 	if (port->mapbase == _Ser1UTCR0) {
682 		if (state)
683 			ASSABET_BCR_clear(ASSABET_BCR_RS232EN);
684 		else
685 			ASSABET_BCR_set(ASSABET_BCR_RS232EN);
686 	}
687 }
688 
689 static struct sa1100_port_fns assabet_port_fns __initdata = {
690 	.pm		= assabet_uart_pm,
691 };
692 
693 static struct map_desc assabet_io_desc[] __initdata = {
694   	{	/* Board Control Register */
695 		.virtual	=  0xf1000000,
696 		.pfn		= __phys_to_pfn(0x12000000),
697 		.length		= 0x00100000,
698 		.type		= MT_DEVICE
699 	}, {	/* MQ200 */
700 		.virtual	=  0xf2800000,
701 		.pfn		= __phys_to_pfn(0x4b800000),
702 		.length		= 0x00800000,
703 		.type		= MT_DEVICE
704 	}
705 };
706 
707 static void __init assabet_map_io(void)
708 {
709 	sa1100_map_io();
710 	iotable_init(assabet_io_desc, ARRAY_SIZE(assabet_io_desc));
711 
712 	/*
713 	 * Set SUS bit in SDCR0 so serial port 1 functions.
714 	 * Its called GPCLKR0 in my SA1110 manual.
715 	 */
716 	Ser1SDCR0 |= SDCR0_SUS;
717 	MSC1 = (MSC1 & ~0xffff) |
718 		MSC_NonBrst | MSC_32BitStMem |
719 		MSC_RdAcc(2) | MSC_WrAcc(2) | MSC_Rec(0);
720 
721 	if (!machine_has_neponset())
722 		sa1100_register_uart_fns(&assabet_port_fns);
723 
724 	/*
725 	 * When Neponset is attached, the first UART should be
726 	 * UART3.  That's what Angel is doing and many documents
727 	 * are stating this.
728 	 *
729 	 * We do the Neponset mapping even if Neponset support
730 	 * isn't compiled in so the user will still get something on
731 	 * the expected physical serial port.
732 	 *
733 	 * We no longer do this; not all boot loaders support it,
734 	 * and UART3 appears to be somewhat unreliable with blob.
735 	 */
736 	sa1100_register_uart(0, 1);
737 	sa1100_register_uart(2, 3);
738 }
739 
740 void __init assabet_init_irq(void)
741 {
742 	unsigned int assabet_gpio_base;
743 	u32 def_val;
744 
745 	sa1100_init_irq();
746 
747 	if (machine_has_neponset())
748 		def_val = ASSABET_BCR_DB1111;
749 	else
750 		def_val = ASSABET_BCR_DB1110;
751 
752 	/*
753 	 * Angel sets this, but other bootloaders may not.
754 	 *
755 	 * This must precede any driver calls to BCR_set() or BCR_clear().
756 	 */
757 	assabet_gpio_base = assabet_init_gpio((void *)&ASSABET_BCR, def_val);
758 
759 	assabet_leds[0].gpio = assabet_gpio_base + 13;
760 	assabet_leds[1].gpio = assabet_gpio_base + 14;
761 }
762 
763 MACHINE_START(ASSABET, "Intel-Assabet")
764 	.atag_offset	= 0x100,
765 	.fixup		= fixup_assabet,
766 	.map_io		= assabet_map_io,
767 	.nr_irqs	= SA1100_NR_IRQS,
768 	.init_irq	= assabet_init_irq,
769 	.init_time	= sa1100_timer_init,
770 	.init_machine	= assabet_init,
771 	.init_late	= sa11x0_init_late,
772 #ifdef CONFIG_SA1111
773 	.dma_zone_size	= SZ_1M,
774 #endif
775 	.restart	= sa11x0_restart,
776 MACHINE_END
777