minix/kernel/arch/earm/arch_reset.c
Thomas Cort 6c6123d857 kernel: implement reboot for am335x/dm37xx
Change-Id: Ied288326b9af8f31223b2dd76a064e32c9a03c45
2013-08-05 10:23:00 -04:00

103 lines
1.8 KiB
C

#include "kernel/kernel.h"
#include <unistd.h>
#include <ctype.h>
#include <string.h>
#include <machine/cpu.h>
#include <assert.h>
#include <signal.h>
#include <machine/vm.h>
#include <io.h>
#include <minix/reboot.h>
#include <minix/u64.h>
#include "archconst.h"
#include "arch_proto.h"
#include "serial.h"
#include "omap_rtc.h"
#include "kernel/proc.h"
#include "kernel/debug.h"
#include "direct_utils.h"
#include <machine/multiboot.h>
void
halt_cpu(void)
{
asm volatile("dsb");
asm volatile("cpsie i");
asm volatile("wfi");
asm volatile("cpsid i");
}
void
reset(void)
{
omap3_reset();
direct_print("Reset not supported.");
while (1);
}
void
poweroff(void)
{
/*
* The am335x can signal an external power management chip to cut the power
* by toggling the PMIC_POWER_EN pin. It might fail if there isn't an
* external PMIC or if the PMIC hasn't been configured to respond to toggles.
* The only way to pull the pin low is via ALARM2 (see TRM 20.3.3.8).
* At this point PM should have already signaled readclock to set the alarm.
*/
#ifdef AM335X
/* Powers down the SoC within 3 seconds */
direct_print("PMIC Power-Off in 3 Seconds\n");
/* rtc was frozen to prevent premature power-off, unfreeze it now */
omap3_rtc_run();
/* wait for the alarm to go off and PMIC to disable power to SoC */
while (1);
#endif /* AM335X */
/* fallback option: hang */
direct_print("Unable to power-off this device.");
while (1);
}
__dead void
arch_shutdown(int how)
{
switch (how) {
case RBT_HALT:
/* Hang */
for (; ; ) halt_cpu();
NOT_REACHABLE;
case RBT_POWEROFF:
/* Power off if possible, hang otherwise */
poweroff();
NOT_REACHABLE;
default:
case RBT_DEFAULT:
case RBT_REBOOT:
case RBT_RESET:
/* Reset the system */
reset();
NOT_REACHABLE;
}
while (1);
}
#ifdef DEBUG_SERIAL
void
ser_putc(char c)
{
omap3_ser_putc(c);
}
#endif