1// SPDX-License-Identifier: GPL-2.0-only
 
 
 
 
  2#include <linux/kernel.h>
  3#include <linux/module.h>
  4#include <linux/delay.h>
  5#include <linux/gpio.h>
  6#include <linux/io.h>
  7#include <asm/proc-fns.h>
  8#include <asm/system_misc.h>
  9
 10#include "regs-ost.h"
 11#include "reset.h"
 12#include "smemc.h"
 13#include "generic.h"
 
 
 14
 15static void do_hw_reset(void);
 16
 17static int reset_gpio = -1;
 18
 19int init_gpio_reset(int gpio, int output, int level)
 20{
 21	int rc;
 22
 23	rc = gpio_request(gpio, "reset generator");
 24	if (rc) {
 25		printk(KERN_ERR "Can't request reset_gpio\n");
 26		goto out;
 27	}
 28
 29	if (output)
 30		rc = gpio_direction_output(gpio, level);
 31	else
 32		rc = gpio_direction_input(gpio);
 33	if (rc) {
 34		printk(KERN_ERR "Can't configure reset_gpio\n");
 35		gpio_free(gpio);
 36		goto out;
 37	}
 38
 39out:
 40	if (!rc)
 41		reset_gpio = gpio;
 42
 43	return rc;
 44}
 45
 46/*
 47 * Trigger GPIO reset.
 48 * This covers various types of logic connecting gpio pin
 49 * to RESET pins (nRESET or GPIO_RESET):
 50 */
 51static void do_gpio_reset(void)
 52{
 53	BUG_ON(reset_gpio == -1);
 54
 55	/* drive it low */
 56	gpio_direction_output(reset_gpio, 0);
 57	mdelay(2);
 58	/* rising edge or drive high */
 59	gpio_set_value(reset_gpio, 1);
 60	mdelay(2);
 61	/* falling edge */
 62	gpio_set_value(reset_gpio, 0);
 63
 64	/* give it some time */
 65	mdelay(10);
 66
 67	WARN_ON(1);
 68	/* fallback */
 69	do_hw_reset();
 70}
 71
 72static void do_hw_reset(void)
 73{
 74	/* Initialize the watchdog and let it fire */
 75	writel_relaxed(OWER_WME, OWER);
 76	writel_relaxed(OSSR_M3, OSSR);
 77	/* ... in 100 ms */
 78	writel_relaxed(readl_relaxed(OSCR) + 368640, OSMR3);
 79	/*
 80	 * SDRAM hangs on watchdog reset on Marvell PXA270 (erratum 71)
 81	 * we put SDRAM into self-refresh to prevent that
 82	 */
 83	while (1)
 84		writel_relaxed(MDREFR_SLFRSH, MDREFR);
 85}
 86
 87void pxa_restart(enum reboot_mode mode, const char *cmd)
 88{
 89	local_irq_disable();
 90	local_fiq_disable();
 91
 92	clear_reset_status(RESET_STATUS_ALL);
 93
 94	switch (mode) {
 95	case REBOOT_SOFT:
 96		/* Jump into ROM at address 0 */
 97		soft_restart(0);
 98		break;
 99	case REBOOT_GPIO:
100		do_gpio_reset();
101		break;
102	case REBOOT_HARD:
103	default:
104		do_hw_reset();
105		break;
106	}
107}

  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}