Last timer instance of GPTIMER is sometimes a watchdog timer that can reset the system on timer underflow. --- c/src/lib/libbsp/sparc/leon3/Makefile.am | 2 + c/src/lib/libbsp/sparc/leon3/include/watchdog.h | 49 ++++++++++++ c/src/lib/libbsp/sparc/leon3/preinstall.am | 4 + c/src/lib/libbsp/sparc/leon3/timer/watchdog.c | 90 +++++++++++++++++++++++ 4 files changed, 145 insertions(+), 0 deletions(-) create mode 100644 c/src/lib/libbsp/sparc/leon3/include/watchdog.h create mode 100644 c/src/lib/libbsp/sparc/leon3/timer/watchdog.c
diff --git a/c/src/lib/libbsp/sparc/leon3/Makefile.am b/c/src/lib/libbsp/sparc/leon3/Makefile.am index cec0b34..4cb6e79 100644 --- a/c/src/lib/libbsp/sparc/leon3/Makefile.am +++ b/c/src/lib/libbsp/sparc/leon3/Makefile.am @@ -125,6 +125,8 @@ libbsp_a_SOURCES += ../../sparc/shared/i2c/i2cmst.c # timer libbsp_a_SOURCES += timer/timer.c +libbsp_a_SOURCES += timer/watchdog.c +include_HEADERS += include/watchdog.h # Cache libbsp_a_SOURCES += ../../../libcpu/shared/src/cache_manager.c diff --git a/c/src/lib/libbsp/sparc/leon3/include/watchdog.h b/c/src/lib/libbsp/sparc/leon3/include/watchdog.h new file mode 100644 index 0000000..fd984e1 --- /dev/null +++ b/c/src/lib/libbsp/sparc/leon3/include/watchdog.h @@ -0,0 +1,49 @@ +/* watchdog.h + * + * The LEON3 BSP timer watch-dog interface + * + * COPYRIGHT (c) 2012. + * Cobham Gaisler AB. + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.com/license/LICENSE. + */ + +#ifndef __WATCHDOG_H__ +#define __WATCHDOG_H__ + +#ifdef __cplusplus +extern "C" { +#endif + +/* Initialize BSP watchdog routines. Returns number of watchdog timers found. + * Currently only one is supported. + */ +int bsp_watchdog_init(void); + +/* Reload watchdog (last timer on the first GPTIMER core), all systems does not + * feature a watchdog, it is expected that if this function is called the + * user knows that there is a watchdog available. + * + * The prescaler is normally set to number of MHz of system, this is to + * make the system clock tick be stable. + * + * Arguments + * watchdog - Always 0 for now + * reload_value - Number of timer clocks (after prescaler) to count before + * watchdog is woken. + */ +void bsp_watchdog_reload(int watchdog, unsigned int reload_value); + +/* Stop watchdog timer */ +void bsp_watchdog_stop(int watchdog); + +/* Use watchdog0 timer to reset the system */ +void bsp_watchdog_system_reset(void); + +#ifdef __cplusplus +} +#endif + +#endif diff --git a/c/src/lib/libbsp/sparc/leon3/preinstall.am b/c/src/lib/libbsp/sparc/leon3/preinstall.am index d7b28e4..0c0139f 100644 --- a/c/src/lib/libbsp/sparc/leon3/preinstall.am +++ b/c/src/lib/libbsp/sparc/leon3/preinstall.am @@ -165,3 +165,7 @@ $(PROJECT_INCLUDE)/i2cmst.h: ../../sparc/shared/include/i2cmst.h $(PROJECT_INCLU $(INSTALL_DATA) $< $(PROJECT_INCLUDE)/i2cmst.h PREINSTALL_FILES += $(PROJECT_INCLUDE)/i2cmst.h +$(PROJECT_INCLUDE)/watchdog.h: include/watchdog.h $(PROJECT_INCLUDE)/$(dirstamp) + $(INSTALL_DATA) $< $(PROJECT_INCLUDE)/watchdog.h +PREINSTALL_FILES += $(PROJECT_INCLUDE)/watchdog.h + diff --git a/c/src/lib/libbsp/sparc/leon3/timer/watchdog.c b/c/src/lib/libbsp/sparc/leon3/timer/watchdog.c new file mode 100644 index 0000000..15e2142 --- /dev/null +++ b/c/src/lib/libbsp/sparc/leon3/timer/watchdog.c @@ -0,0 +1,90 @@ +/* GPTIMER Watchdog timer routines. On some systems the first GPTIMER + * core's last Timer instance underflow signal is connected to system + * reset. + * + * COPYRIGHT (c) 2012. + * Cobham Gaisler AB. + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.com/license/LICENSE. + */ + +#include <bsp.h> +#include <watchdog.h> +#include <grlib.h> + +extern volatile struct gptimer_regs *LEON3_Timer_Regs; + +struct gptimer_watchdog_priv { + struct gptimer_regs *regs; + struct gptimer_timer_regs *timer; + int timerno; +}; + +struct gptimer_watchdog_priv bsp_watchdogs[1]; +int bsp_watchdog_count = 0; + +int bsp_watchdog_init(void) +{ + int timercnt; + + if (!LEON3_Timer_Regs) + return 0; + + /* Get Watchdogs in system, this is implemented for one GPTIMER core + * only. + * + * First watchdog is a special case, we can get the first timer core by + * looking at LEON3_Timer_Regs, the watchdog within a timer core is + * always the last timer. Unfortunately we can not know it the watchdog + * functionality is available or not, we assume that it is if we + * reached this function. + */ + bsp_watchdogs[0].regs = (struct gptimer_regs *)LEON3_Timer_Regs; + + /* Find Timer that has watchdog functionality */ + timercnt = bsp_watchdogs[0].regs->cfg & 0x7; + if (timercnt < 2) /* First timer system clock timer */ + return 0; + + bsp_watchdogs[0].timerno = timercnt - 1; + bsp_watchdogs[0].timer = &bsp_watchdogs[0].regs->timer[bsp_watchdogs[0].timerno]; + + bsp_watchdog_count = 1; + return bsp_watchdog_count; +} + +void bsp_watchdog_reload(int watchdog, unsigned int reload_value) +{ + if (bsp_watchdog_count == 0) + bsp_watchdog_init(); + + if (bsp_watchdog_count <= watchdog) + return; + + /* Kick watchdog, and clear interrupt pending bit */ + bsp_watchdogs[watchdog].timer->reload = reload_value; + bsp_watchdogs[watchdog].timer->ctrl = + (LEON3_GPTIMER_LD | LEON3_GPTIMER_EN) | + (bsp_watchdogs[watchdog].timer->ctrl & ~(1<<4)); +} + +void bsp_watchdog_stop(int watchdog) +{ + if (bsp_watchdog_count == 0) + bsp_watchdog_init(); + + if (bsp_watchdog_count <= watchdog) + return; + + /* Stop watchdog timer */ + bsp_watchdogs[watchdog].timer->ctrl = 0; +} + +/* Use watchdog timer to reset system */ +void bsp_watchdog_system_reset(void) +{ + sparc_disable_interrupts(); + bsp_watchdog_reload(0, 1); +} -- 1.7.0.4 _______________________________________________ devel mailing list devel@rtems.org http://lists.rtems.org/mailman/listinfo/devel
