From 7e91901303219f10cf865906931c07c31d2e37f4 Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Tue, 4 Jul 2017 14:15:03 +0200 Subject: arm: Fix ARMv7-M interrupt processing Right after a "msr basepri_max, %[basepri]" instruction an interrupt service may still take place (observed at least on Cortex-M7). However, pendable service calls that are activated during this interrupt service may be delayed until interrupts are enable again. The _ARMV7M_Pendable_service_call() did not check that a thread dispatch is allowed. Move this test from _ARMV7M_Interrupt_service_leave() to _ARMV7M_Pendable_service_call(). Close #3060. --- cpukit/score/cpu/arm/armv7m-isr-dispatch.c | 50 ++++++++++++++++++------------ 1 file changed, 31 insertions(+), 19 deletions(-) (limited to 'cpukit/score/cpu/arm/armv7m-isr-dispatch.c') diff --git a/cpukit/score/cpu/arm/armv7m-isr-dispatch.c b/cpukit/score/cpu/arm/armv7m-isr-dispatch.c index e460e9c3e7..ffd1589db1 100644 --- a/cpukit/score/cpu/arm/armv7m-isr-dispatch.c +++ b/cpukit/score/cpu/arm/armv7m-isr-dispatch.c @@ -5,10 +5,10 @@ */ /* - * Copyright (c) 2011-2014 Sebastian Huber. All rights reserved. + * Copyright (c) 2011, 2017 Sebastian Huber. All rights reserved. * * embedded brains GmbH - * Obere Lagerstr. 30 + * Dornierstr. 4 * 82178 Puchheim * Germany * @@ -48,29 +48,42 @@ static void _ARMV7M_Trigger_lazy_floating_point_context_save( void ) void _ARMV7M_Pendable_service_call( void ) { - ARMV7M_Exception_frame *ef; + Per_CPU_Control *cpu_self = _Per_CPU_Get(); - _ISR_Nest_level = 1; + /* + * We must check here if a thread dispatch is allowed. Right after a + * "msr basepri_max, %[basepri]" instruction an interrupt service may still + * take place. However, pendable service calls that are activated during + * this interrupt service may be delayed until interrupts are enable again. + */ + if ( + ( cpu_self->isr_nest_level | cpu_self->thread_dispatch_disable_level ) == 0 + ) { + ARMV7M_Exception_frame *ef; - _ARMV7M_SCB->icsr = ARMV7M_SCB_ICSR_PENDSVCLR; - _ARMV7M_Trigger_lazy_floating_point_context_save(); + cpu_self->isr_nest_level = 1; - ef = (ARMV7M_Exception_frame *) _ARMV7M_Get_PSP(); - --ef; - _ARMV7M_Set_PSP( (uint32_t) ef ); + _ARMV7M_SCB->icsr = ARMV7M_SCB_ICSR_PENDSVCLR; + _ARMV7M_Trigger_lazy_floating_point_context_save(); - /* - * According to "ARMv7-M Architecture Reference Manual" section B1.5.6 - * "Exception entry behavior" the return address is half-word aligned. - */ - ef->register_pc = (void *) - ((uintptr_t) _ARMV7M_Thread_dispatch & ~((uintptr_t) 1)); + ef = (ARMV7M_Exception_frame *) _ARMV7M_Get_PSP(); + --ef; + _ARMV7M_Set_PSP( (uint32_t) ef ); - ef->register_xpsr = 0x01000000U; + /* + * According to "ARMv7-M Architecture Reference Manual" section B1.5.6 + * "Exception entry behavior" the return address is half-word aligned. + */ + ef->register_pc = (void *) + ((uintptr_t) _ARMV7M_Thread_dispatch & ~((uintptr_t) 1)); + + ef->register_xpsr = 0x01000000U; + } } void _ARMV7M_Supervisor_call( void ) { + Per_CPU_Control *cpu_self = _Per_CPU_Get(); ARMV7M_Exception_frame *ef; _ARMV7M_Trigger_lazy_floating_point_context_save(); @@ -79,10 +92,9 @@ void _ARMV7M_Supervisor_call( void ) ++ef; _ARMV7M_Set_PSP( (uint32_t) ef ); - _ISR_Nest_level = 0; - RTEMS_COMPILER_MEMORY_BARRIER(); + cpu_self->isr_nest_level = 0; - if ( _Thread_Dispatch_necessary ) { + if ( cpu_self->dispatch_necessary ) { _ARMV7M_Pendable_service_call(); } } -- cgit v1.2.3