1/*
2 * linux/arch/arm/plat-omap/common.c
3 *
4 * Code common to all OMAP machines.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/delay.h>
14#include <linux/pm.h>
15#include <linux/console.h>
16#include <linux/serial.h>
17#include <linux/tty.h>
18#include <linux/serial_8250.h>
19#include <linux/serial_reg.h>
20#include <linux/clk.h>
21
22#include <asm/hardware.h>
23#include <asm/system.h>
24#include <asm/pgtable.h>
25#include <asm/mach/map.h>
26#include <asm/io.h>
27#include <asm/setup.h>
28
29#include <asm/arch/board.h>
30#include <asm/arch/mux.h>
31#include <asm/arch/fpga.h>
32
33#include <asm/arch/clock.h>
34
35#define NO_LENGTH_CHECK 0xffffffff
36
37unsigned char omap_bootloader_tag[512];
38int omap_bootloader_tag_len;
39
40struct omap_board_config_kernel *omap_board_config;
41int omap_board_config_size;
42
43static const void *get_config(u16 tag, size_t len, int skip, size_t *len_out)
44{
45	struct omap_board_config_kernel *kinfo = NULL;
46	int i;
47
48#ifdef CONFIG_OMAP_BOOT_TAG
49	struct omap_board_config_entry *info = NULL;
50
51	if (omap_bootloader_tag_len > 4)
52		info = (struct omap_board_config_entry *) omap_bootloader_tag;
53	while (info != NULL) {
54		u8 *next;
55
56		if (info->tag == tag) {
57			if (skip == 0)
58				break;
59			skip--;
60		}
61
62		if ((info->len & 0x03) != 0) {
63			/* We bail out to avoid an alignment fault */
64			printk(KERN_ERR "OMAP peripheral config: Length (%d) not word-aligned (tag %04x)\n",
65			       info->len, info->tag);
66			return NULL;
67		}
68		next = (u8 *) info + sizeof(*info) + info->len;
69		if (next >= omap_bootloader_tag + omap_bootloader_tag_len)
70			info = NULL;
71		else
72			info = (struct omap_board_config_entry *) next;
73	}
74	if (info != NULL) {
75		/* Check the length as a lame attempt to check for
76		 * binary inconsistency. */
77		if (len != NO_LENGTH_CHECK) {
78			/* Word-align len */
79			if (len & 0x03)
80				len = (len + 3) & ~0x03;
81			if (info->len != len) {
82				printk(KERN_ERR "OMAP peripheral config: Length mismatch with tag %x (want %d, got %d)\n",
83				       tag, len, info->len);
84				return NULL;
85			}
86		}
87		if (len_out != NULL)
88			*len_out = info->len;
89		return info->data;
90	}
91#endif
92	/* Try to find the config from the board-specific structures
93	 * in the kernel. */
94	for (i = 0; i < omap_board_config_size; i++) {
95		if (omap_board_config[i].tag == tag) {
96			if (skip == 0) {
97				kinfo = &omap_board_config[i];
98				break;
99			} else {
100				skip--;
101			}
102		}
103	}
104	if (kinfo == NULL)
105		return NULL;
106	return kinfo->data;
107}
108
109const void *__omap_get_config(u16 tag, size_t len, int nr)
110{
111        return get_config(tag, len, nr, NULL);
112}
113EXPORT_SYMBOL(__omap_get_config);
114
115const void *omap_get_var_config(u16 tag, size_t *len)
116{
117        return get_config(tag, NO_LENGTH_CHECK, 0, len);
118}
119EXPORT_SYMBOL(omap_get_var_config);
120
121static int __init omap_add_serial_console(void)
122{
123	const struct omap_serial_console_config *con_info;
124	const struct omap_uart_config *uart_info;
125	static char speed[11], *opt = NULL;
126	int line, i, uart_idx;
127
128	uart_info = omap_get_config(OMAP_TAG_UART, struct omap_uart_config);
129	con_info = omap_get_config(OMAP_TAG_SERIAL_CONSOLE,
130					struct omap_serial_console_config);
131	if (uart_info == NULL || con_info == NULL)
132		return 0;
133
134	if (con_info->console_uart == 0)
135		return 0;
136
137	if (con_info->console_speed) {
138		snprintf(speed, sizeof(speed), "%u", con_info->console_speed);
139		opt = speed;
140	}
141
142	uart_idx = con_info->console_uart - 1;
143	if (uart_idx >= OMAP_MAX_NR_PORTS) {
144		printk(KERN_INFO "Console: external UART#%d. "
145			"Not adding it as console this time.\n",
146			uart_idx + 1);
147		return 0;
148	}
149	if (!(uart_info->enabled_uarts & (1 << uart_idx))) {
150		printk(KERN_ERR "Console: Selected UART#%d is "
151			"not enabled for this platform\n",
152			uart_idx + 1);
153		return -1;
154	}
155	line = 0;
156	for (i = 0; i < uart_idx; i++) {
157		if (uart_info->enabled_uarts & (1 << i))
158			line++;
159	}
160	return add_preferred_console("ttyS", line, opt);
161}
162console_initcall(omap_add_serial_console);
163
164
165/*
166 * 32KHz clocksource ... always available, on pretty most chips except
167 * OMAP 730 and 1510.  Other timers could be used as clocksources, with
168 * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
169 * but systems won't necessarily want to spend resources that way.
170 */
171
172#if defined(CONFIG_ARCH_OMAP16XX)
173#define TIMER_32K_SYNCHRONIZED		0xfffbc410
174#elif defined(CONFIG_ARCH_OMAP24XX)
175#define TIMER_32K_SYNCHRONIZED		0x48004010
176#endif
177
178#ifdef	TIMER_32K_SYNCHRONIZED
179
180#include <linux/clocksource.h>
181
182static cycle_t omap_32k_read(void)
183{
184	return omap_readl(TIMER_32K_SYNCHRONIZED);
185}
186
187static struct clocksource clocksource_32k = {
188	.name		= "32k_counter",
189	.rating		= 250,
190	.read		= omap_32k_read,
191	.mask		= CLOCKSOURCE_MASK(32),
192	.shift		= 10,
193	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
194};
195
196static int __init omap_init_clocksource_32k(void)
197{
198	static char err[] __initdata = KERN_ERR
199			"%s: can't register clocksource!\n";
200
201	if (cpu_is_omap16xx() || cpu_is_omap24xx()) {
202		clocksource_32k.mult = clocksource_hz2mult(32768,
203					    clocksource_32k.shift);
204
205		if (clocksource_register(&clocksource_32k))
206			printk(err, clocksource_32k.name);
207	}
208	return 0;
209}
210arch_initcall(omap_init_clocksource_32k);
211
212#endif	/* TIMER_32K_SYNCHRONIZED */
213