linux/arch/mips/jz4740/reset.c
Maarten ter Huurne ea3952e01c MIPS: JZ4740: reset: Initialize hibernate wakeup counters.
In hibernation mode only the wakeup logic and the RTC are left running,
so this is what users perceive as power down.

If the counters are not initialized, the corresponding pin (typically
connected to the power button) has to be asserted for two seconds
before the device wakes up. Most users expect a shorter wakeup time.

I took the timing values of 100 ms and 60 ms from BouKiCHi's patch for
the Dingoo A320 kernel.

Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Cc: Sergei Shtylyov <sshtylyov@mvista.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3563/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-07-23 13:56:20 +01:00

119 lines
3.1 KiB
C

/*
* Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/pm.h>
#include <asm/reboot.h>
#include <asm/mach-jz4740/base.h>
#include <asm/mach-jz4740/timer.h>
#include "reset.h"
#include "clock.h"
static void jz4740_halt(void)
{
while (1) {
__asm__(".set push;\n"
".set mips3;\n"
"wait;\n"
".set pop;\n"
);
}
}
#define JZ_REG_WDT_DATA 0x00
#define JZ_REG_WDT_COUNTER_ENABLE 0x04
#define JZ_REG_WDT_COUNTER 0x08
#define JZ_REG_WDT_CTRL 0x0c
static void jz4740_restart(char *command)
{
void __iomem *wdt_base = ioremap(JZ4740_WDT_BASE_ADDR, 0x0f);
jz4740_timer_enable_watchdog();
writeb(0, wdt_base + JZ_REG_WDT_COUNTER_ENABLE);
writew(0, wdt_base + JZ_REG_WDT_COUNTER);
writew(0, wdt_base + JZ_REG_WDT_DATA);
writew(BIT(2), wdt_base + JZ_REG_WDT_CTRL);
writeb(1, wdt_base + JZ_REG_WDT_COUNTER_ENABLE);
jz4740_halt();
}
#define JZ_REG_RTC_CTRL 0x00
#define JZ_REG_RTC_HIBERNATE 0x20
#define JZ_REG_RTC_WAKEUP_FILTER 0x24
#define JZ_REG_RTC_RESET_COUNTER 0x28
#define JZ_RTC_CTRL_WRDY BIT(7)
#define JZ_RTC_WAKEUP_FILTER_MASK 0x0000FFE0
#define JZ_RTC_RESET_COUNTER_MASK 0x00000FE0
static inline void jz4740_rtc_wait_ready(void __iomem *rtc_base)
{
uint32_t ctrl;
do {
ctrl = readl(rtc_base + JZ_REG_RTC_CTRL);
} while (!(ctrl & JZ_RTC_CTRL_WRDY));
}
static void jz4740_power_off(void)
{
void __iomem *rtc_base = ioremap(JZ4740_RTC_BASE_ADDR, 0x38);
unsigned long wakeup_filter_ticks;
unsigned long reset_counter_ticks;
/*
* Set minimum wakeup pin assertion time: 100 ms.
* Range is 0 to 2 sec if RTC is clocked at 32 kHz.
*/
wakeup_filter_ticks = (100 * jz4740_clock_bdata.rtc_rate) / 1000;
if (wakeup_filter_ticks < JZ_RTC_WAKEUP_FILTER_MASK)
wakeup_filter_ticks &= JZ_RTC_WAKEUP_FILTER_MASK;
else
wakeup_filter_ticks = JZ_RTC_WAKEUP_FILTER_MASK;
jz4740_rtc_wait_ready(rtc_base);
writel(wakeup_filter_ticks, rtc_base + JZ_REG_RTC_WAKEUP_FILTER);
/*
* Set reset pin low-level assertion time after wakeup: 60 ms.
* Range is 0 to 125 ms if RTC is clocked at 32 kHz.
*/
reset_counter_ticks = (60 * jz4740_clock_bdata.rtc_rate) / 1000;
if (reset_counter_ticks < JZ_RTC_RESET_COUNTER_MASK)
reset_counter_ticks &= JZ_RTC_RESET_COUNTER_MASK;
else
reset_counter_ticks = JZ_RTC_RESET_COUNTER_MASK;
jz4740_rtc_wait_ready(rtc_base);
writel(reset_counter_ticks, rtc_base + JZ_REG_RTC_RESET_COUNTER);
jz4740_rtc_wait_ready(rtc_base);
writel(1, rtc_base + JZ_REG_RTC_HIBERNATE);
jz4740_halt();
}
void jz4740_reset_init(void)
{
_machine_restart = jz4740_restart;
_machine_halt = jz4740_halt;
pm_power_off = jz4740_power_off;
}