linux/arch/arm/mach-at91/generic.h
Johan Hovold 94c4c79f2f ARM: at91: fix hanged boot due to early rtt-interrupt
Make sure the RTT-interrupts are masked at boot by adding a new helper
function to be used at SOC-init.

This fixes hanged boot on all AT91 SOCs with an RTT, for example, if an
RTT-alarm goes off after a non-clean shutdown (e.g. when using RTC
wakeup).

The RTC and RTT-peripherals are powered by backup power (VDDBU) (on all
AT91 SOCs but RM9200) and are not reset on wake-up, user, watchdog or
software reset. This means that their interrupts may be enabled during
early boot if, for example, they where not disabled during a previous
shutdown (e.g. due to a buggy driver or a non-clean shutdown such as a
user reset). Furthermore, an RTC or RTT-alarm may also be active.

The RTC and RTT-interrupts use the shared system-interrupt line, which
is also used by the PIT, and if an interrupt occurs before a handler
(e.g. RTC-driver) has been installed this leads to the system interrupt
being disabled and prevents the system from booting.

Note that when boot hangs due to an early RTC or RTT-interrupt, the only
way to get the system to start again is to remove the backup power (e.g.
battery) or to disable the interrupt manually from the bootloader. In
particular, a user reset is not sufficient.

Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: stable@vger.kernel.org # 3.11.x
2013-11-15 12:13:33 +01:00

92 lines
2.9 KiB
C

/*
* linux/arch/arm/mach-at91/generic.h
*
* Copyright (C) 2005 David Brownell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/clkdev.h>
#include <linux/of.h>
#include <linux/reboot.h>
/* Map io */
extern void __init at91_map_io(void);
extern void __init at91_init_sram(int bank, unsigned long base,
unsigned int length);
/* Processors */
extern void __init at91rm9200_set_type(int type);
extern void __init at91_initialize(unsigned long main_clock);
extern void __init at91x40_initialize(unsigned long main_clock);
extern void __init at91rm9200_dt_initialize(void);
extern void __init at91_dt_initialize(void);
/* Interrupts */
extern void __init at91_init_irq_default(void);
extern void __init at91_init_interrupts(unsigned int priority[]);
extern void __init at91x40_init_interrupts(unsigned int priority[]);
extern void __init at91_aic_init(unsigned int priority[],
unsigned int ext_irq_mask);
extern int __init at91_aic_of_init(struct device_node *node,
struct device_node *parent);
extern int __init at91_aic5_of_init(struct device_node *node,
struct device_node *parent);
extern void __init at91_sysirq_mask_rtc(u32 rtc_base);
extern void __init at91_sysirq_mask_rtt(u32 rtt_base);
/* Timer */
extern void at91rm9200_ioremap_st(u32 addr);
extern void at91rm9200_timer_init(void);
extern void at91sam926x_ioremap_pit(u32 addr);
extern void at91sam926x_pit_init(void);
extern void at91x40_timer_init(void);
/* Clocks */
#ifdef CONFIG_AT91_PMC_UNIT
extern int __init at91_clock_init(unsigned long main_clock);
extern int __init at91_dt_clock_init(void);
#else
static int inline at91_clock_init(unsigned long main_clock) { return 0; }
#endif
struct device;
/* Power Management */
extern void at91_irq_suspend(void);
extern void at91_irq_resume(void);
/* idle */
extern void at91sam9_idle(void);
/* reset */
extern void at91_ioremap_rstc(u32 base_addr);
extern void at91sam9_alt_restart(enum reboot_mode, const char *);
extern void at91sam9g45_restart(enum reboot_mode, const char *);
/* shutdown */
extern void at91_ioremap_shdwc(u32 base_addr);
/* Matrix */
extern void at91_ioremap_matrix(u32 base_addr);
/* Ram Controler */
extern void at91_ioremap_ramc(int id, u32 addr, u32 size);
/* GPIO */
#define AT91RM9200_PQFP 3 /* AT91RM9200 PQFP package has 3 banks */
#define AT91RM9200_BGA 4 /* AT91RM9200 BGA package has 4 banks */
struct at91_gpio_bank {
unsigned short id; /* peripheral ID */
unsigned long regbase; /* offset from system peripheral base */
};
extern void __init at91_gpio_init(struct at91_gpio_bank *, int nr_banks);
extern void __init at91_gpio_irq_setup(void);
extern int __init at91_gpio_of_irq_setup(struct device_node *node,
struct device_node *parent);
extern u32 at91_get_extern_irq(void);