xref: /openbmc/linux/arch/arm/mach-ep93xx/core.c (revision 64c70b1c)
1 /*
2  * arch/arm/mach-ep93xx/core.c
3  * Core routines for Cirrus EP93xx chips.
4  *
5  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
6  *
7  * Thanks go to Michael Burian and Ray Lehtiniemi for their key
8  * role in the ep93xx linux community.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or (at
13  * your option) any later version.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/init.h>
18 #include <linux/spinlock.h>
19 #include <linux/sched.h>
20 #include <linux/interrupt.h>
21 #include <linux/serial.h>
22 #include <linux/tty.h>
23 #include <linux/bitops.h>
24 #include <linux/serial.h>
25 #include <linux/serial_8250.h>
26 #include <linux/serial_core.h>
27 #include <linux/device.h>
28 #include <linux/mm.h>
29 #include <linux/time.h>
30 #include <linux/timex.h>
31 #include <linux/delay.h>
32 #include <linux/termios.h>
33 #include <linux/amba/bus.h>
34 #include <linux/amba/serial.h>
35 
36 #include <asm/types.h>
37 #include <asm/setup.h>
38 #include <asm/memory.h>
39 #include <asm/hardware.h>
40 #include <asm/irq.h>
41 #include <asm/system.h>
42 #include <asm/tlbflush.h>
43 #include <asm/pgtable.h>
44 #include <asm/io.h>
45 
46 #include <asm/mach/map.h>
47 #include <asm/mach/time.h>
48 #include <asm/mach/irq.h>
49 #include <asm/arch/gpio.h>
50 
51 #include <asm/hardware/vic.h>
52 
53 
54 /*************************************************************************
55  * Static I/O mappings that are needed for all EP93xx platforms
56  *************************************************************************/
57 static struct map_desc ep93xx_io_desc[] __initdata = {
58 	{
59 		.virtual	= EP93XX_AHB_VIRT_BASE,
60 		.pfn		= __phys_to_pfn(EP93XX_AHB_PHYS_BASE),
61 		.length		= EP93XX_AHB_SIZE,
62 		.type		= MT_DEVICE,
63 	}, {
64 		.virtual	= EP93XX_APB_VIRT_BASE,
65 		.pfn		= __phys_to_pfn(EP93XX_APB_PHYS_BASE),
66 		.length		= EP93XX_APB_SIZE,
67 		.type		= MT_DEVICE,
68 	},
69 };
70 
71 void __init ep93xx_map_io(void)
72 {
73 	iotable_init(ep93xx_io_desc, ARRAY_SIZE(ep93xx_io_desc));
74 }
75 
76 
77 /*************************************************************************
78  * Timer handling for EP93xx
79  *************************************************************************
80  * The ep93xx has four internal timers.  Timers 1, 2 (both 16 bit) and
81  * 3 (32 bit) count down at 508 kHz, are self-reloading, and can generate
82  * an interrupt on underflow.  Timer 4 (40 bit) counts down at 983.04 kHz,
83  * is free-running, and can't generate interrupts.
84  *
85  * The 508 kHz timers are ideal for use for the timer interrupt, as the
86  * most common values of HZ divide 508 kHz nicely.  We pick one of the 16
87  * bit timers (timer 1) since we don't need more than 16 bits of reload
88  * value as long as HZ >= 8.
89  *
90  * The higher clock rate of timer 4 makes it a better choice than the
91  * other timers for use in gettimeoffset(), while the fact that it can't
92  * generate interrupts means we don't have to worry about not being able
93  * to use this timer for something else.  We also use timer 4 for keeping
94  * track of lost jiffies.
95  */
96 static unsigned int last_jiffy_time;
97 
98 #define TIMER4_TICKS_PER_JIFFY		((CLOCK_TICK_RATE + (HZ/2)) / HZ)
99 
100 static int ep93xx_timer_interrupt(int irq, void *dev_id)
101 {
102 	write_seqlock(&xtime_lock);
103 
104 	__raw_writel(1, EP93XX_TIMER1_CLEAR);
105 	while ((signed long)
106 		(__raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time)
107 						>= TIMER4_TICKS_PER_JIFFY) {
108 		last_jiffy_time += TIMER4_TICKS_PER_JIFFY;
109 		timer_tick();
110 	}
111 
112 	write_sequnlock(&xtime_lock);
113 
114 	return IRQ_HANDLED;
115 }
116 
117 static struct irqaction ep93xx_timer_irq = {
118 	.name		= "ep93xx timer",
119 	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
120 	.handler	= ep93xx_timer_interrupt,
121 };
122 
123 static void __init ep93xx_timer_init(void)
124 {
125 	/* Enable periodic HZ timer.  */
126 	__raw_writel(0x48, EP93XX_TIMER1_CONTROL);
127 	__raw_writel((508469 / HZ) - 1, EP93XX_TIMER1_LOAD);
128 	__raw_writel(0xc8, EP93XX_TIMER1_CONTROL);
129 
130 	/* Enable lost jiffy timer.  */
131 	__raw_writel(0x100, EP93XX_TIMER4_VALUE_HIGH);
132 
133 	setup_irq(IRQ_EP93XX_TIMER1, &ep93xx_timer_irq);
134 }
135 
136 static unsigned long ep93xx_gettimeoffset(void)
137 {
138 	int offset;
139 
140 	offset = __raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time;
141 
142 	/* Calculate (1000000 / 983040) * offset.  */
143 	return offset + (53 * offset / 3072);
144 }
145 
146 struct sys_timer ep93xx_timer = {
147 	.init		= ep93xx_timer_init,
148 	.offset		= ep93xx_gettimeoffset,
149 };
150 
151 
152 /*************************************************************************
153  * GPIO handling for EP93xx
154  *************************************************************************/
155 static unsigned char gpio_int_unmasked[3];
156 static unsigned char gpio_int_enabled[3];
157 static unsigned char gpio_int_type1[3];
158 static unsigned char gpio_int_type2[3];
159 
160 static void update_gpio_int_params(int abf)
161 {
162 	if (abf == 0) {
163 		__raw_writeb(0, EP93XX_GPIO_A_INT_ENABLE);
164 		__raw_writeb(gpio_int_type2[0], EP93XX_GPIO_A_INT_TYPE2);
165 		__raw_writeb(gpio_int_type1[0], EP93XX_GPIO_A_INT_TYPE1);
166 		__raw_writeb(gpio_int_unmasked[0] & gpio_int_enabled[0], EP93XX_GPIO_A_INT_ENABLE);
167 	} else if (abf == 1) {
168 		__raw_writeb(0, EP93XX_GPIO_B_INT_ENABLE);
169 		__raw_writeb(gpio_int_type2[1], EP93XX_GPIO_B_INT_TYPE2);
170 		__raw_writeb(gpio_int_type1[1], EP93XX_GPIO_B_INT_TYPE1);
171 		__raw_writeb(gpio_int_unmasked[1] & gpio_int_enabled[1], EP93XX_GPIO_B_INT_ENABLE);
172 	} else if (abf == 2) {
173 		__raw_writeb(0, EP93XX_GPIO_F_INT_ENABLE);
174 		__raw_writeb(gpio_int_type2[2], EP93XX_GPIO_F_INT_TYPE2);
175 		__raw_writeb(gpio_int_type1[2], EP93XX_GPIO_F_INT_TYPE1);
176 		__raw_writeb(gpio_int_unmasked[2] & gpio_int_enabled[2], EP93XX_GPIO_F_INT_ENABLE);
177 	} else {
178 		BUG();
179 	}
180 }
181 
182 
183 static unsigned char data_register_offset[8] = {
184 	0x00, 0x04, 0x08, 0x0c, 0x20, 0x30, 0x38, 0x40,
185 };
186 
187 static unsigned char data_direction_register_offset[8] = {
188 	0x10, 0x14, 0x18, 0x1c, 0x24, 0x34, 0x3c, 0x44,
189 };
190 
191 void gpio_line_config(int line, int direction)
192 {
193 	unsigned int data_direction_register;
194 	unsigned long flags;
195 	unsigned char v;
196 
197 	data_direction_register =
198 		EP93XX_GPIO_REG(data_direction_register_offset[line >> 3]);
199 
200 	local_irq_save(flags);
201 	if (direction == GPIO_OUT) {
202 		if (line >= 0 && line < 16) {
203 			/* Port A/B.  */
204 			gpio_int_unmasked[line >> 3] &= ~(1 << (line & 7));
205 			update_gpio_int_params(line >> 3);
206 		} else if (line >= 40 && line < 48) {
207 			/* Port F.  */
208 			gpio_int_unmasked[2] &= ~(1 << (line & 7));
209 			update_gpio_int_params(2);
210 		}
211 
212 		v = __raw_readb(data_direction_register);
213 		v |= 1 << (line & 7);
214 		__raw_writeb(v, data_direction_register);
215 	} else if (direction == GPIO_IN) {
216 		v = __raw_readb(data_direction_register);
217 		v &= ~(1 << (line & 7));
218 		__raw_writeb(v, data_direction_register);
219 	}
220 	local_irq_restore(flags);
221 }
222 EXPORT_SYMBOL(gpio_line_config);
223 
224 int gpio_line_get(int line)
225 {
226 	unsigned int data_register;
227 
228 	data_register = EP93XX_GPIO_REG(data_register_offset[line >> 3]);
229 
230 	return !!(__raw_readb(data_register) & (1 << (line & 7)));
231 }
232 EXPORT_SYMBOL(gpio_line_get);
233 
234 void gpio_line_set(int line, int value)
235 {
236 	unsigned int data_register;
237 	unsigned long flags;
238 	unsigned char v;
239 
240 	data_register = EP93XX_GPIO_REG(data_register_offset[line >> 3]);
241 
242 	local_irq_save(flags);
243 	if (value == EP93XX_GPIO_HIGH) {
244 		v = __raw_readb(data_register);
245 		v |= 1 << (line & 7);
246 		__raw_writeb(v, data_register);
247 	} else if (value == EP93XX_GPIO_LOW) {
248 		v = __raw_readb(data_register);
249 		v &= ~(1 << (line & 7));
250 		__raw_writeb(v, data_register);
251 	}
252 	local_irq_restore(flags);
253 }
254 EXPORT_SYMBOL(gpio_line_set);
255 
256 
257 /*************************************************************************
258  * EP93xx IRQ handling
259  *************************************************************************/
260 static void ep93xx_gpio_ab_irq_handler(unsigned int irq, struct irq_desc *desc)
261 {
262 	unsigned char status;
263 	int i;
264 
265 	status = __raw_readb(EP93XX_GPIO_A_INT_STATUS);
266 	for (i = 0; i < 8; i++) {
267 		if (status & (1 << i)) {
268 			desc = irq_desc + IRQ_EP93XX_GPIO(0) + i;
269 			desc_handle_irq(IRQ_EP93XX_GPIO(0) + i, desc);
270 		}
271 	}
272 
273 	status = __raw_readb(EP93XX_GPIO_B_INT_STATUS);
274 	for (i = 0; i < 8; i++) {
275 		if (status & (1 << i)) {
276 			desc = irq_desc + IRQ_EP93XX_GPIO(8) + i;
277 			desc_handle_irq(IRQ_EP93XX_GPIO(8) + i, desc);
278 		}
279 	}
280 }
281 
282 static void ep93xx_gpio_f_irq_handler(unsigned int irq, struct irq_desc *desc)
283 {
284 	int gpio_irq = IRQ_EP93XX_GPIO(16) + (((irq + 1) & 7) ^ 4);
285 
286 	desc_handle_irq(gpio_irq, irq_desc + gpio_irq);
287 }
288 
289 static void ep93xx_gpio_irq_mask_ack(unsigned int irq)
290 {
291 	int line = irq - IRQ_EP93XX_GPIO(0);
292 	int port = line >> 3;
293 
294 	gpio_int_unmasked[port] &= ~(1 << (line & 7));
295 	update_gpio_int_params(port);
296 
297 	if (port == 0) {
298 		__raw_writel(1 << (line & 7), EP93XX_GPIO_A_INT_ACK);
299 	} else if (port == 1) {
300 		__raw_writel(1 << (line & 7), EP93XX_GPIO_B_INT_ACK);
301 	} else if (port == 2) {
302 		__raw_writel(1 << (line & 7), EP93XX_GPIO_F_INT_ACK);
303 	}
304 }
305 
306 static void ep93xx_gpio_irq_mask(unsigned int irq)
307 {
308 	int line = irq - IRQ_EP93XX_GPIO(0);
309 	int port = line >> 3;
310 
311 	gpio_int_unmasked[port] &= ~(1 << (line & 7));
312 	update_gpio_int_params(port);
313 }
314 
315 static void ep93xx_gpio_irq_unmask(unsigned int irq)
316 {
317 	int line = irq - IRQ_EP93XX_GPIO(0);
318 	int port = line >> 3;
319 
320 	gpio_int_unmasked[port] |= 1 << (line & 7);
321 	update_gpio_int_params(port);
322 }
323 
324 
325 /*
326  * gpio_int_type1 controls whether the interrupt is level (0) or
327  * edge (1) triggered, while gpio_int_type2 controls whether it
328  * triggers on low/falling (0) or high/rising (1).
329  */
330 static int ep93xx_gpio_irq_type(unsigned int irq, unsigned int type)
331 {
332 	int port;
333 	int line;
334 
335 	line = irq - IRQ_EP93XX_GPIO(0);
336 	if (line >= 0 && line < 16) {
337 		gpio_line_config(line, GPIO_IN);
338 	} else {
339 		gpio_line_config(EP93XX_GPIO_LINE_F(line), GPIO_IN);
340 	}
341 
342 	port = line >> 3;
343 	line &= 7;
344 
345 	if (type & IRQT_RISING) {
346 		gpio_int_enabled[port] |= 1 << line;
347 		gpio_int_type1[port] |= 1 << line;
348 		gpio_int_type2[port] |= 1 << line;
349 	} else if (type & IRQT_FALLING) {
350 		gpio_int_enabled[port] |= 1 << line;
351 		gpio_int_type1[port] |= 1 << line;
352 		gpio_int_type2[port] &= ~(1 << line);
353 	} else if (type & IRQT_HIGH) {
354 		gpio_int_enabled[port] |= 1 << line;
355 		gpio_int_type1[port] &= ~(1 << line);
356 		gpio_int_type2[port] |= 1 << line;
357 	} else if (type & IRQT_LOW) {
358 		gpio_int_enabled[port] |= 1 << line;
359 		gpio_int_type1[port] &= ~(1 << line);
360 		gpio_int_type2[port] &= ~(1 << line);
361 	} else {
362 		gpio_int_enabled[port] &= ~(1 << line);
363 	}
364 	update_gpio_int_params(port);
365 
366 	return 0;
367 }
368 
369 static struct irq_chip ep93xx_gpio_irq_chip = {
370 	.name		= "GPIO",
371 	.ack		= ep93xx_gpio_irq_mask_ack,
372 	.mask		= ep93xx_gpio_irq_mask,
373 	.unmask		= ep93xx_gpio_irq_unmask,
374 	.set_type	= ep93xx_gpio_irq_type,
375 };
376 
377 
378 void __init ep93xx_init_irq(void)
379 {
380 	int irq;
381 
382 	vic_init((void *)EP93XX_VIC1_BASE, 0, EP93XX_VIC1_VALID_IRQ_MASK);
383 	vic_init((void *)EP93XX_VIC2_BASE, 32, EP93XX_VIC2_VALID_IRQ_MASK);
384 
385 	for (irq = IRQ_EP93XX_GPIO(0); irq <= IRQ_EP93XX_GPIO(23); irq++) {
386 		set_irq_chip(irq, &ep93xx_gpio_irq_chip);
387 		set_irq_handler(irq, handle_level_irq);
388 		set_irq_flags(irq, IRQF_VALID);
389 	}
390 
391 	set_irq_chained_handler(IRQ_EP93XX_GPIO_AB, ep93xx_gpio_ab_irq_handler);
392 	set_irq_chained_handler(IRQ_EP93XX_GPIO0MUX, ep93xx_gpio_f_irq_handler);
393 	set_irq_chained_handler(IRQ_EP93XX_GPIO1MUX, ep93xx_gpio_f_irq_handler);
394 	set_irq_chained_handler(IRQ_EP93XX_GPIO2MUX, ep93xx_gpio_f_irq_handler);
395 	set_irq_chained_handler(IRQ_EP93XX_GPIO3MUX, ep93xx_gpio_f_irq_handler);
396 	set_irq_chained_handler(IRQ_EP93XX_GPIO4MUX, ep93xx_gpio_f_irq_handler);
397 	set_irq_chained_handler(IRQ_EP93XX_GPIO5MUX, ep93xx_gpio_f_irq_handler);
398 	set_irq_chained_handler(IRQ_EP93XX_GPIO6MUX, ep93xx_gpio_f_irq_handler);
399 	set_irq_chained_handler(IRQ_EP93XX_GPIO7MUX, ep93xx_gpio_f_irq_handler);
400 }
401 
402 
403 /*************************************************************************
404  * EP93xx peripheral handling
405  *************************************************************************/
406 #define EP93XX_UART_MCR_OFFSET		(0x0100)
407 
408 static void ep93xx_uart_set_mctrl(struct amba_device *dev,
409 				  void __iomem *base, unsigned int mctrl)
410 {
411 	unsigned int mcr;
412 
413 	mcr = 0;
414 	if (!(mctrl & TIOCM_RTS))
415 		mcr |= 2;
416 	if (!(mctrl & TIOCM_DTR))
417 		mcr |= 1;
418 
419 	__raw_writel(mcr, base + EP93XX_UART_MCR_OFFSET);
420 }
421 
422 static struct amba_pl010_data ep93xx_uart_data = {
423 	.set_mctrl	= ep93xx_uart_set_mctrl,
424 };
425 
426 static struct amba_device uart1_device = {
427 	.dev		= {
428 		.bus_id		= "apb:uart1",
429 		.platform_data	= &ep93xx_uart_data,
430 	},
431 	.res		= {
432 		.start	= EP93XX_UART1_PHYS_BASE,
433 		.end	= EP93XX_UART1_PHYS_BASE + 0x0fff,
434 		.flags	= IORESOURCE_MEM,
435 	},
436 	.irq		= { IRQ_EP93XX_UART1, NO_IRQ },
437 	.periphid	= 0x00041010,
438 };
439 
440 static struct amba_device uart2_device = {
441 	.dev		= {
442 		.bus_id		= "apb:uart2",
443 		.platform_data	= &ep93xx_uart_data,
444 	},
445 	.res		= {
446 		.start	= EP93XX_UART2_PHYS_BASE,
447 		.end	= EP93XX_UART2_PHYS_BASE + 0x0fff,
448 		.flags	= IORESOURCE_MEM,
449 	},
450 	.irq		= { IRQ_EP93XX_UART2, NO_IRQ },
451 	.periphid	= 0x00041010,
452 };
453 
454 static struct amba_device uart3_device = {
455 	.dev		= {
456 		.bus_id		= "apb:uart3",
457 		.platform_data	= &ep93xx_uart_data,
458 	},
459 	.res		= {
460 		.start	= EP93XX_UART3_PHYS_BASE,
461 		.end	= EP93XX_UART3_PHYS_BASE + 0x0fff,
462 		.flags	= IORESOURCE_MEM,
463 	},
464 	.irq		= { IRQ_EP93XX_UART3, NO_IRQ },
465 	.periphid	= 0x00041010,
466 };
467 
468 
469 static struct platform_device ep93xx_rtc_device = {
470        .name           = "ep93xx-rtc",
471        .id             = -1,
472        .num_resources  = 0,
473 };
474 
475 
476 static struct resource ep93xx_ohci_resources[] = {
477 	[0] = {
478 		.start	= EP93XX_USB_PHYS_BASE,
479 		.end	= EP93XX_USB_PHYS_BASE + 0x0fff,
480 		.flags	= IORESOURCE_MEM,
481 	},
482 	[1] = {
483 		.start	= IRQ_EP93XX_USB,
484 		.end	= IRQ_EP93XX_USB,
485 		.flags	= IORESOURCE_IRQ,
486 	},
487 };
488 
489 static struct platform_device ep93xx_ohci_device = {
490 	.name		= "ep93xx-ohci",
491 	.id		= -1,
492 	.dev		= {
493 		.dma_mask		= (void *)0xffffffff,
494 		.coherent_dma_mask	= 0xffffffff,
495 	},
496 	.num_resources	= ARRAY_SIZE(ep93xx_ohci_resources),
497 	.resource	= ep93xx_ohci_resources,
498 };
499 
500 
501 void __init ep93xx_init_devices(void)
502 {
503 	unsigned int v;
504 
505 	/*
506 	 * Disallow access to MaverickCrunch initially.
507 	 */
508 	v = __raw_readl(EP93XX_SYSCON_DEVICE_CONFIG);
509 	v &= ~EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE;
510 	__raw_writel(0xaa, EP93XX_SYSCON_SWLOCK);
511 	__raw_writel(v, EP93XX_SYSCON_DEVICE_CONFIG);
512 
513 	amba_device_register(&uart1_device, &iomem_resource);
514 	amba_device_register(&uart2_device, &iomem_resource);
515 	amba_device_register(&uart3_device, &iomem_resource);
516 
517 	platform_device_register(&ep93xx_rtc_device);
518 	platform_device_register(&ep93xx_ohci_device);
519 }
520