From 762fa62ccaebadb7fa486da634c27b02960112b1 Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Tue, 22 May 2018 08:52:13 +0200 Subject: arm: Simplify CPU counter support Use the standard ARMv7-M systick module for the ARMv7-M CPU counter instead of DWT counter since the DWT counter is affected by power saving states. Use an inline function for _CPU_Counter_difference() for all ARM BSPs. Update #3456. --- bsps/arm/include/bsp/clock-armv7m.h | 78 +++++++++++++ bsps/arm/lpc176x/start/system-clocks.c | 9 -- bsps/arm/shared/clock/clock-armv7m.c | 151 +++++++++---------------- bsps/arm/shared/cpucounter/cpucounter-armv7m.c | 37 +----- 4 files changed, 133 insertions(+), 142 deletions(-) create mode 100644 bsps/arm/include/bsp/clock-armv7m.h (limited to 'bsps') diff --git a/bsps/arm/include/bsp/clock-armv7m.h b/bsps/arm/include/bsp/clock-armv7m.h new file mode 100644 index 0000000000..d635fb0c1b --- /dev/null +++ b/bsps/arm/include/bsp/clock-armv7m.h @@ -0,0 +1,78 @@ +/* + * Copyright (c) 2011, 2018 Sebastian Huber. All rights reserved. + * + * embedded brains GmbH + * Dornierstr. 4 + * 82178 Puchheim + * Germany + * + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.org/license/LICENSE. + */ + +#ifndef BSP_CLOCK_ARMV7M_H +#define BSP_CLOCK_ARMV7M_H + +#include +#include + +#include + +#ifdef __cplusplus +extern "C" { +#endif /* __cplusplus */ + +#ifdef ARM_MULTILIB_ARCH_V7M + +typedef struct { + struct timecounter base; + uint32_t ticks; +} ARMV7M_Timecounter; + +extern ARMV7M_Timecounter _ARMV7M_TC; + +static inline uint32_t _ARMV7M_Clock_frequency(void) +{ +#ifdef BSP_ARMV7M_SYSTICK_FREQUENCY + return BSP_ARMV7M_SYSTICK_FREQUENCY; +#else + volatile ARMV7M_Systick *systick = _ARMV7M_Systick; + return ARMV7M_SYSTICK_CALIB_TENMS_GET(systick->calib) * 100; +#endif +} + +static uint32_t _ARMV7M_Clock_counter(ARMV7M_Timecounter *tc) +{ + volatile ARMV7M_Systick *systick; + rtems_interrupt_level level; + uint32_t interval; + uint32_t counter; + uint32_t ticks; + + systick = _ARMV7M_Systick; + interval = systick->rvr; + + rtems_interrupt_disable(level); + counter = systick->cvr; + ticks = tc->ticks; + + if ((systick->csr & ARMV7M_SYSTICK_CSR_COUNTFLAG) != 0) { + ticks += interval; + tc->ticks = ticks; + } + + counter = interval - counter + ticks; + rtems_interrupt_enable(level); + + return counter; +} + +#endif /* ARM_MULTILIB_ARCH_V7M */ + +#ifdef __cplusplus +} +#endif /* __cplusplus */ + +#endif /* BSP_CLOCK_ARMV7M_H */ diff --git a/bsps/arm/lpc176x/start/system-clocks.c b/bsps/arm/lpc176x/start/system-clocks.c index 2ec58727eb..6af52be053 100644 --- a/bsps/arm/lpc176x/start/system-clocks.c +++ b/bsps/arm/lpc176x/start/system-clocks.c @@ -118,12 +118,3 @@ CPU_Counter_ticks _CPU_Counter_read( void ) { return lpc176x_get_timer1(); } - -inline CPU_Counter_ticks _CPU_Counter_difference( - CPU_Counter_ticks second, - CPU_Counter_ticks first -) -{ - return second - first; -} - diff --git a/bsps/arm/shared/clock/clock-armv7m.c b/bsps/arm/shared/clock/clock-armv7m.c index 39cd4efdc7..2efe4c2654 100644 --- a/bsps/arm/shared/clock/clock-armv7m.c +++ b/bsps/arm/shared/clock/clock-armv7m.c @@ -1,8 +1,8 @@ /* - * Copyright (c) 2011-2012 Sebastian Huber. All rights reserved. + * Copyright (c) 2011, 2018 Sebastian Huber. All rights reserved. * * embedded brains GmbH - * Obere Lagerstr. 30 + * Dornierstr. 4 * 82178 Puchheim * Germany * @@ -12,146 +12,97 @@ * http://www.rtems.org/license/LICENSE. */ -#include -#include -#include +#include -#include +#include +#include #ifdef ARM_MULTILIB_ARCH_V7M /* This is defined in dev/clock/clockimpl.h */ static void Clock_isr(void *arg); -typedef struct { - rtems_timecounter_simple base; - void (*tick)(void); - bool countflag; -} ARMV7M_Timecounter; - -static ARMV7M_Timecounter _ARMV7M_TC; - -static uint32_t _ARMV7M_TC_systick_get(rtems_timecounter_simple *tc) -{ - volatile ARMV7M_Systick *systick = _ARMV7M_Systick; - - return systick->cvr; -} - -static bool _ARMV7M_TC_systick_is_pending(rtems_timecounter_simple *base) -{ - ARMV7M_Timecounter *tc = (ARMV7M_Timecounter *) base; - rtems_interrupt_level level; - bool countflag; - - rtems_interrupt_disable(level); - - countflag = tc->countflag; - if (!countflag) { - volatile ARMV7M_Systick *systick = _ARMV7M_Systick; - - countflag = ((systick->csr & ARMV7M_SYSTICK_CSR_COUNTFLAG) != 0); - tc->countflag = countflag; - } - - rtems_interrupt_enable(level); - - return countflag; -} - -static uint32_t _ARMV7M_TC_systick_get_timecount(struct timecounter *tc) -{ - return rtems_timecounter_simple_downcounter_get( - tc, - _ARMV7M_TC_systick_get, - _ARMV7M_TC_systick_is_pending - ); -} - -static void _ARMV7M_TC_systick_at_tick(rtems_timecounter_simple *base) -{ - ARMV7M_Timecounter *tc = (ARMV7M_Timecounter *) base; - volatile ARMV7M_Systick *systick = _ARMV7M_Systick; - - tc->countflag = false; - - /* Clear COUNTFLAG */ - systick->csr; -} +ARMV7M_Timecounter _ARMV7M_TC; -static void _ARMV7M_TC_systick_tick(void) +static uint32_t _ARMV7M_TC_get_timecount(struct timecounter *base) { - rtems_timecounter_simple_downcounter_tick( - &_ARMV7M_TC.base, - _ARMV7M_TC_systick_get, - _ARMV7M_TC_systick_at_tick - ); + return _ARMV7M_Clock_counter((ARMV7M_Timecounter *) base); } -static void _ARMV7M_TC_tick(void) -{ - (*_ARMV7M_TC.tick)(); -} - -static void _ARMV7M_Systick_handler(void) +static void _ARMV7M_Clock_handler(void) { _ARMV7M_Interrupt_service_enter(); Clock_isr(NULL); _ARMV7M_Interrupt_service_leave(); } -static void _ARMV7M_Systick_handler_install(void) +static void _ARMV7M_Clock_handler_install(void) { _ARMV7M_Set_exception_priority_and_handler( ARMV7M_VECTOR_SYSTICK, BSP_ARMV7M_SYSTICK_PRIORITY, - _ARMV7M_Systick_handler + _ARMV7M_Clock_handler ); } -static void _ARMV7M_Systick_initialize(void) +static void _ARMV7M_Clock_initialize(void) { - volatile ARMV7M_Systick *systick = _ARMV7M_Systick; - #ifdef BSP_ARMV7M_SYSTICK_FREQUENCY - uint64_t freq = BSP_ARMV7M_SYSTICK_FREQUENCY; - #else - uint64_t freq = ARMV7M_SYSTICK_CALIB_TENMS_GET(systick->calib) * 100ULL; - #endif - uint64_t us_per_tick = rtems_configuration_get_microseconds_per_tick(); - uint64_t interval = (freq * us_per_tick) / 1000000ULL; - - systick->rvr = (uint32_t) interval; - systick->cvr = 0; + volatile ARMV7M_Systick *systick; + ARMV7M_Timecounter *tc; + + systick = _ARMV7M_Systick; + tc = &_ARMV7M_TC; + systick->csr = ARMV7M_SYSTICK_CSR_ENABLE | ARMV7M_SYSTICK_CSR_TICKINT | ARMV7M_SYSTICK_CSR_CLKSOURCE; - _ARMV7M_TC.tick = _ARMV7M_TC_systick_tick; - rtems_timecounter_simple_install( - &_ARMV7M_TC.base, - freq, - interval, - _ARMV7M_TC_systick_get_timecount - ); + tc->base.tc_get_timecount = _ARMV7M_TC_get_timecount; + tc->base.tc_counter_mask = 0xffffffff; + tc->base.tc_frequency = _ARMV7M_Clock_frequency(); + tc->base.tc_quality = RTEMS_TIMECOUNTER_QUALITY_CLOCK_DRIVER; + rtems_timecounter_install(&tc->base); } -static void _ARMV7M_Systick_cleanup(void) +static void _ARMV7M_Clock_initialize_early(void) +{ + volatile ARMV7M_Systick *systick; + uint32_t us_per_tick; + uint64_t freq; + uint32_t interval; + + systick = _ARMV7M_Systick; + us_per_tick = rtems_configuration_get_microseconds_per_tick(); + freq = _ARMV7M_Clock_frequency(); + + interval = (uint32_t) ((freq * us_per_tick) / 1000000); + + systick->rvr = interval; + systick->cvr = 0; + systick->csr = ARMV7M_SYSTICK_CSR_ENABLE | ARMV7M_SYSTICK_CSR_CLKSOURCE; +} + +RTEMS_SYSINIT_ITEM( + _ARMV7M_Clock_initialize_early, + RTEMS_SYSINIT_CPU_COUNTER, + RTEMS_SYSINIT_ORDER_FIRST +); + +static void _ARMV7M_Clock_cleanup(void) { volatile ARMV7M_Systick *systick = _ARMV7M_Systick; systick->csr = 0; } -#define Clock_driver_timecounter_tick() _ARMV7M_TC_tick() - #define Clock_driver_support_initialize_hardware() \ - _ARMV7M_Systick_initialize() + _ARMV7M_Clock_initialize() #define Clock_driver_support_install_isr(isr) \ - _ARMV7M_Systick_handler_install() + _ARMV7M_Clock_handler_install() #define Clock_driver_support_shutdown_hardware() \ - _ARMV7M_Systick_cleanup() + _ARMV7M_Clock_cleanup() /* Include shared source clock driver code */ #include "../../../shared/dev/clock/clockimpl.h" diff --git a/bsps/arm/shared/cpucounter/cpucounter-armv7m.c b/bsps/arm/shared/cpucounter/cpucounter-armv7m.c index b7593602ed..bb7cdc441b 100644 --- a/bsps/arm/shared/cpucounter/cpucounter-armv7m.c +++ b/bsps/arm/shared/cpucounter/cpucounter-armv7m.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2016 embedded brains GmbH. All rights reserved. + * Copyright (c) 2016, 2018 embedded brains GmbH. All rights reserved. * * embedded brains GmbH * Dornierstr. 4 @@ -12,43 +12,14 @@ * http://www.rtems.org/license/LICENSE. */ -#include -#include -#include - -#include -#include +#include uint32_t _CPU_Counter_frequency(void) { -#ifdef BSP_ARMV7M_SYSTICK_FREQUENCY - return = BSP_ARMV7M_SYSTICK_FREQUENCY; -#else - volatile ARMV7M_Systick *systick = _ARMV7M_Systick; - return ARMV7M_SYSTICK_CALIB_TENMS_GET(systick->calib) * 100; -#endif + return _ARMV7M_Clock_frequency(); } CPU_Counter_ticks _CPU_Counter_read(void) { - volatile ARMV7M_DWT *dwt = _ARMV7M_DWT; - - return dwt->cyccnt; -} - -static void armv7m_cpu_counter_initialize(void) -{ - bool cyccnt_enabled; - - cyccnt_enabled = _ARMV7M_DWT_Enable_CYCCNT(); - - if (!cyccnt_enabled) { - bsp_fatal(BSP_ARM_ARMV7M_CPU_COUNTER_INIT); - } + return _ARMV7M_Clock_counter(&_ARMV7M_TC); } - -RTEMS_SYSINIT_ITEM( - armv7m_cpu_counter_initialize, - RTEMS_SYSINIT_CPU_COUNTER, - RTEMS_SYSINIT_ORDER_FIRST -); -- cgit v1.2.3