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v3.15
  1/*
  2 * This program is free software; you can redistribute it and/or modify
  3 * it under the terms of the GNU General Public License version 2 as
  4 * published by the Free Software Foundation.
  5 */
  6#include <linux/kernel.h>
  7#include <linux/module.h>
  8#include <linux/delay.h>
  9#include <linux/gpio.h>
 10#include <linux/io.h>
 11#include <asm/proc-fns.h>
 12#include <asm/system_misc.h>
 13
 14#include <mach/regs-ost.h>
 15#include <mach/reset.h>
 16#include <mach/smemc.h>
 17
 18unsigned int reset_status;
 19EXPORT_SYMBOL(reset_status);
 20
 21static void do_hw_reset(void);
 22
 23static int reset_gpio = -1;
 24
 25int init_gpio_reset(int gpio, int output, int level)
 26{
 27	int rc;
 28
 29	rc = gpio_request(gpio, "reset generator");
 30	if (rc) {
 31		printk(KERN_ERR "Can't request reset_gpio\n");
 32		goto out;
 33	}
 34
 35	if (output)
 36		rc = gpio_direction_output(gpio, level);
 37	else
 38		rc = gpio_direction_input(gpio);
 39	if (rc) {
 40		printk(KERN_ERR "Can't configure reset_gpio\n");
 41		gpio_free(gpio);
 42		goto out;
 43	}
 44
 45out:
 46	if (!rc)
 47		reset_gpio = gpio;
 48
 49	return rc;
 50}
 51
 52/*
 53 * Trigger GPIO reset.
 54 * This covers various types of logic connecting gpio pin
 55 * to RESET pins (nRESET or GPIO_RESET):
 56 */
 57static void do_gpio_reset(void)
 58{
 59	BUG_ON(reset_gpio == -1);
 60
 61	/* drive it low */
 62	gpio_direction_output(reset_gpio, 0);
 63	mdelay(2);
 64	/* rising edge or drive high */
 65	gpio_set_value(reset_gpio, 1);
 66	mdelay(2);
 67	/* falling edge */
 68	gpio_set_value(reset_gpio, 0);
 69
 70	/* give it some time */
 71	mdelay(10);
 72
 73	WARN_ON(1);
 74	/* fallback */
 75	do_hw_reset();
 76}
 77
 78static void do_hw_reset(void)
 79{
 80	/* Initialize the watchdog and let it fire */
 81	writel_relaxed(OWER_WME, OWER);
 82	writel_relaxed(OSSR_M3, OSSR);
 83	/* ... in 100 ms */
 84	writel_relaxed(readl_relaxed(OSCR) + 368640, OSMR3);
 85	/*
 86	 * SDRAM hangs on watchdog reset on Marvell PXA270 (erratum 71)
 87	 * we put SDRAM into self-refresh to prevent that
 88	 */
 89	while (1)
 90		writel_relaxed(MDREFR_SLFRSH, MDREFR);
 91}
 92
 93void pxa_restart(enum reboot_mode mode, const char *cmd)
 94{
 95	local_irq_disable();
 96	local_fiq_disable();
 97
 98	clear_reset_status(RESET_STATUS_ALL);
 99
100	switch (mode) {
101	case REBOOT_SOFT:
102		/* Jump into ROM at address 0 */
103		soft_restart(0);
104		break;
105	case REBOOT_GPIO:
106		do_gpio_reset();
107		break;
108	case REBOOT_HARD:
109	default:
110		do_hw_reset();
111		break;
112	}
113}
v3.5.6
  1/*
  2 * This program is free software; you can redistribute it and/or modify
  3 * it under the terms of the GNU General Public License version 2 as
  4 * published by the Free Software Foundation.
  5 */
  6#include <linux/kernel.h>
  7#include <linux/module.h>
  8#include <linux/delay.h>
  9#include <linux/gpio.h>
 10#include <linux/io.h>
 11#include <asm/proc-fns.h>
 12#include <asm/system_misc.h>
 13
 14#include <mach/regs-ost.h>
 15#include <mach/reset.h>
 
 16
 17unsigned int reset_status;
 18EXPORT_SYMBOL(reset_status);
 19
 20static void do_hw_reset(void);
 21
 22static int reset_gpio = -1;
 23
 24int init_gpio_reset(int gpio, int output, int level)
 25{
 26	int rc;
 27
 28	rc = gpio_request(gpio, "reset generator");
 29	if (rc) {
 30		printk(KERN_ERR "Can't request reset_gpio\n");
 31		goto out;
 32	}
 33
 34	if (output)
 35		rc = gpio_direction_output(gpio, level);
 36	else
 37		rc = gpio_direction_input(gpio);
 38	if (rc) {
 39		printk(KERN_ERR "Can't configure reset_gpio\n");
 40		gpio_free(gpio);
 41		goto out;
 42	}
 43
 44out:
 45	if (!rc)
 46		reset_gpio = gpio;
 47
 48	return rc;
 49}
 50
 51/*
 52 * Trigger GPIO reset.
 53 * This covers various types of logic connecting gpio pin
 54 * to RESET pins (nRESET or GPIO_RESET):
 55 */
 56static void do_gpio_reset(void)
 57{
 58	BUG_ON(reset_gpio == -1);
 59
 60	/* drive it low */
 61	gpio_direction_output(reset_gpio, 0);
 62	mdelay(2);
 63	/* rising edge or drive high */
 64	gpio_set_value(reset_gpio, 1);
 65	mdelay(2);
 66	/* falling edge */
 67	gpio_set_value(reset_gpio, 0);
 68
 69	/* give it some time */
 70	mdelay(10);
 71
 72	WARN_ON(1);
 73	/* fallback */
 74	do_hw_reset();
 75}
 76
 77static void do_hw_reset(void)
 78{
 79	/* Initialize the watchdog and let it fire */
 80	OWER = OWER_WME;
 81	OSSR = OSSR_M3;
 82	OSMR3 = OSCR + 368640;	/* ... in 100 ms */
 
 
 
 
 
 
 
 83}
 84
 85void pxa_restart(char mode, const char *cmd)
 86{
 87	local_irq_disable();
 88	local_fiq_disable();
 89
 90	clear_reset_status(RESET_STATUS_ALL);
 91
 92	switch (mode) {
 93	case 's':
 94		/* Jump into ROM at address 0 */
 95		soft_restart(0);
 96		break;
 97	case 'g':
 98		do_gpio_reset();
 99		break;
100	case 'h':
101	default:
102		do_hw_reset();
103		break;
104	}
105}
106