/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
/**
* @file IAR/ARMCMx/chcore_v6m.h
* @brief ARMv6-M architecture port macros and structures.
*
* @addtogroup IAR_ARMCMx_V6M_CORE
* @{
*/
#ifndef _CHCORE_V6M_H_
#define _CHCORE_V6M_H_
/*===========================================================================*/
/* Port constants. */
/*===========================================================================*/
/**
* @brief PendSV priority level.
* @note This priority is enforced to be equal to @p 0,
* this handler always have the highest priority that cannot preempt
* the kernel.
*/
#define CORTEX_PRIORITY_PENDSV 0
/*===========================================================================*/
/* Port macros. */
/*===========================================================================*/
/*===========================================================================*/
/* Port configurable parameters. */
/*===========================================================================*/
/**
* @brief Stack size for the system idle thread.
* @details This size depends on the idle thread implementation, usually
* the idle thread should take no more space than those reserved
* by @p PORT_INT_REQUIRED_STACK.
* @note In this port it is set to 16 because the idle thread does have
* a stack frame when compiling without optimizations. You may
* reduce this value to zero when compiling with optimizations.
*/
#if !defined(PORT_IDLE_THREAD_STACK_SIZE)
#define PORT_IDLE_THREAD_STACK_SIZE 16
#endif
/**
* @brief Per-thread stack overhead for interrupts servicing.
* @details This constant is used in the calculation of the correct working
* area size.
* This value can be zero on those architecture where there is a
* separate interrupt stack and the stack space between @p intctx and
* @p extctx is known to be zero.
* @note In this port it is conservatively set to 16 because the function
* @p chSchDoReschedule() can have a stack frame, especially with
* compiler optimizations disabled.
*/
#if !defined(PORT_INT_REQUIRED_STACK)
#define PORT_INT_REQUIRED_STACK 16
#endif
/**
* @brief Enables the use of the WFI instruction in the idle thread loop.
*/
#if !defined(CORTEX_ENABLE_WFI_IDLE)
#define CORTEX_ENABLE_WFI_IDLE FALSE
#endif
/**
* @brief SYSTICK handler priority.
* @note The default SYSTICK handler priority is calculated as the priority
* level in the middle of the numeric priorities range.
*/
#if !defined(CORTEX_PRIORITY_SYSTICK)
#define CORTEX_PRIORITY_SYSTICK (CORTEX_PRIORITY_LEVELS >> 1)
#elif !CORTEX_IS_VALID_PRIORITY(CORTEX_PRIORITY_SYSTICK)
/* If it is externally redefined then better perform a validity check on it.*/
#error "invalid priority level specified for CORTEX_PRIORITY_SYSTICK"
#endif
/**
* @brief Alternate preemption method.
* @details Activating this option will make the Kernel use the PendSV
* handler for preemption instead of the NMI handler.
*/
#ifndef CORTEX_ALTERNATE_SWITCH
#define CORTEX_ALTERNATE_SWITCH FALSE
#endif
/*===========================================================================*/
/* Port derived parameters. */
/*===========================================================================*/
/*===========================================================================*/
/* Port exported info. */
/*===========================================================================*/
/**
* @brief Macro defining the specific ARM architecture.
*/
#define CH_ARCHITECTURE_ARM_v6M
/**
* @brief Name of the implemented architecture.
*/
#define CH_ARCHITECTURE_NAME "ARMv6-M"
/**
* @brief Name of the architecture variant.
*/
#if (CORTEX_MODEL == CORTEX_M0) || defined(__DOXYGEN__)
#define CH_CORE_VARIANT_NAME "Cortex-M0"
#elif (CORTEX_MODEL == CORTEX_M1)
#define CH_CORE_VARIANT_NAME "Cortex-M1"
#endif
/**
* @brief Port-specific information string.
*/
#if !CORTEX_ALTERNATE_SWITCH || defined(__DOXYGEN__)
#define CH_PORT_INFO "Preemption through NMI"
#else
#define CH_PORT_INFO "Preemption through PendSV"
#endif
/*===========================================================================*/
/* Port implementation part. */
/*===========================================================================*/
#if !defined(_FROM_ASM_)
/**
* @brief Generic ARM register.
*/
typedef void *regarm_t;
/**
* @brief Stack and memory alignment enforcement.
* @note In this architecture the stack alignment is enforced to 64 bits,
* 32 bits alignment is supported by hardware but deprecated by ARM,
* the implementation choice is to not offer the option.
*/
typedef uint64_t stkalign_t;
/* The documentation of the following declarations is in chconf.h in order
to not have duplicated structure names into the documentation.*/
#if !defined(__DOXYGEN__)
struct extctx {
regarm_t r0;
regarm_t r1;
regarm_t r2;
regarm_t r3;
regarm_t r12;
regarm_t lr_thd;
regarm_t pc;
regarm_t xpsr;
};
struct intctx {
regarm_t r8;
regarm_t r9;
regarm_t r10;
regarm_t r11;
regarm_t r4;
regarm_t r5;
regarm_t r6;
regarm_t r7;
regarm_t lr;
};
#endif /* !defined(__DOXYGEN__) */
/**
* @brief Platform dependent part of the @p Thread structure.
* @details In this port the structure just holds a pointer to the @p intctx
* structure representing the stack pointer at context switch time.
*/
struct context {
struct intctx *r13;
};
/**
* @brief Platform dependent part of the @p chThdCreateI() API.
* @details This code usually setup the context switching frame represented
* by an @p intctx structure.
*/
#define SETUP_CONTEXT(workspace, wsize, pf, arg) { \
tp->p_ctx.r13 = (struct intctx *)((uint8_t *)workspace + \
wsize - \
sizeof(struct intctx)); \
tp->p_ctx.r13->r4 = (regarm_t)pf; \
tp->p_ctx.r13->r5 = (regarm_t)arg; \
tp->p_ctx.r13->lr = (regarm_t)_port_thread_start; \
}
/**
* @brief Enforces a correct alignment for a stack area size value.
*/
#define STACK_ALIGN(n) ((((n) - 1) | (sizeof(stkalign_t) - 1)) + 1)
/**
* @brief Computes the thread working area global size.
*/
#define THD_WA_SIZE(n) STACK_ALIGN(sizeof(Thread) + \
sizeof(struct intctx) + \
sizeof(struct extctx) + \
(n) + (PORT_INT_REQUIRED_STACK))
/**
* @brief Static working area allocation.
* @details This macro is used to allocate a static thread working area
* aligned as both position and size.
*/
#define WORKING_AREA(s, n) stkalign_t s[THD_WA_SIZE(n) / sizeof(stkalign_t)]
/**
* @brief IRQ prologue code.
* @details This macro must be inserted at the start of all IRQ handlers
* enabled to invoke system APIs.
*/
#define PORT_IRQ_PROLOGUE() regarm_t _saved_lr = (regarm_t)__get_LR()
/**
* @brief IRQ epilogue code.
* @details This macro must be inserted at the end of all IRQ handlers
* enabled to invoke system APIs.
*/
#define PORT_IRQ_EPILOGUE() _port_irq_epilogue(_saved_lr)
/**
* @brief IRQ handler function declaration.
* @note @p id can be a function name or a vector number depending on the
* port implementation.
*/
#define PORT_IRQ_HANDLER(id) void id(void)
/**
* @brief Fast IRQ handler function declaration.
* @note @p id can be a function name or a vector number depending on the
* port implementation.
*/
#define PORT_FAST_IRQ_HANDLER(id) void id(void)
/**
* @brief Port-related initialization code.
*/
#define port_init() { \
SCB_AIRCR = AIRCR_VECTKEY | AIRCR_PRIGROUP(0); \
nvicSetSystemHandlerPriority(HANDLER_PENDSV, \
CORTEX_PRIORITY_MASK(CORTEX_PRIORITY_PENDSV)); \
nvicSetSystemHandlerPriority(HANDLER_SYSTICK, \
CORTEX_PRIORITY_MASK(CORTEX_PRIORITY_SYSTICK)); \
}
/**
* @brief Kernel-lock action.
* @details Usually this function just disables interrupts but may perform
* more actions.
*/
#define port_lock() __disable_interrupt()
/**
* @brief Kernel-unlock action.
* @details Usually this function just enables interrupts but may perform
* more actions.
*/
#define port_unlock() __enable_interrupt()
/**
* @brief Kernel-lock action from an interrupt handler.
* @details This function is invoked before invoking I-class APIs from
* interrupt handlers. The implementation is architecture dependent,
* in its simplest form it is void.
* @note Same as @p port_lock() in this port.
*/
#define port_lock_from_isr() port_lock()
/**
* @brief Kernel-unlock action from an interrupt handler.
* @details This function is invoked after invoking I-class APIs from interrupt
* handlers. The implementation is architecture dependent, in its
* simplest form it is void.
* @note Same as @p port_lock() in this port.
*/
#define port_unlock_from_isr() port_unlock()
/**
* @brief Disables all the interrupt sources.
*/
#define port_disable() __disable_interrupt()
/**
* @brief Disables the interrupt sources below kernel-level priority.
*/
#define port_suspend() __disable_interrupt()
/**
* @brief Enables all the interrupt sources.
*/
#define port_enable() __enable_interrupt()
/**
* @brief Enters an architecture-dependent IRQ-waiting mode.
* @details The function is meant to return when an interrupt becomes pending.
* The simplest implementation is an empty function or macro but this
* would not take advantage of architecture-specific power saving
* modes.
* @note Implemented as an inlined @p WFI instruction.
*/
#if CORTEX_ENABLE_WFI_IDLE || defined(__DOXYGEN__)
#define port_wait_for_interrupt() asm ("wfi")
#else
#define port_wait_for_interrupt()
#endif
/**
* @brief Performs a context switch between two threads.
* @details This is the most critical code in any port, this function
* is responsible for the context switch between 2 threads.
* @note The implementation of this code affects directly the context
* switch performance so optimize here as much as you can.
*
* @param[in] ntp the thread to be switched in
* @param[in] otp the thread to be switched out
*/
#if !CH_DBG_ENABLE_STACK_CHECK || defined(__DOXYGEN__)
#define port_switch(ntp, otp) _port_switch(ntp, otp)
#else
#define port_switch(ntp, otp) { \
if ((stkalign_t *)(__get_SP() - sizeof(struct intctx)) < otp->p_stklimit) \
chDbgPanic("stack overflow"); \
_port_switch(ntp, otp); \
}
#endif
#ifdef __cplusplus
extern "C" {
#endif
void port_halt(void);
void _port_irq_epilogue(regarm_t lr);
void _port_switch_from_isr(void);
void _port_exit_from_isr(void);
void _port_switch(Thread *ntp, Thread *otp);
void _port_thread_start(void);
#ifdef __cplusplus
}
#endif
#endif /* _FROM_ASM_ */
#endif /* _CHCORE_V6M_H_ */
/** @} */