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/*
* ARMv7M NVIC object
*
* Copyright (c) 2017 Linaro Ltd
* Written by Peter Maydell <peter.maydell@linaro.org>
*
* This code is licensed under the GPL version 2 or later.
*/
#ifndef HW_ARM_ARMV7M_NVIC_H
#define HW_ARM_ARMV7M_NVIC_H
#include "target/arm/cpu.h"
#include "hw/sysbus.h"
#include "hw/timer/armv7m_systick.h"
#include "qom/object.h"
#define TYPE_NVIC "armv7m_nvic"
OBJECT_DECLARE_SIMPLE_TYPE(NVICState, NVIC)
/* Highest permitted number of exceptions (architectural limit) */
#define NVIC_MAX_VECTORS 512
/* Number of internal exceptions */
#define NVIC_INTERNAL_VECTORS 16
typedef struct VecInfo {
/* Exception priorities can range from -3 to 255; only the unmodifiable
* priority values for RESET, NMI and HardFault can be negative.
*/
int16_t prio;
uint8_t enabled;
uint8_t pending;
uint8_t active;
uint8_t level; /* exceptions <=15 never set level */
} VecInfo;
struct NVICState {
/*< private >*/
SysBusDevice parent_obj;
/*< public >*/
ARMCPU *cpu;
VecInfo vectors[NVIC_MAX_VECTORS];
/* If the v8M security extension is implemented, some of the internal
* exceptions are banked between security states (ie there exists both
* a Secure and a NonSecure version of the exception and its state):
* HardFault, MemManage, UsageFault, SVCall, PendSV, SysTick (R_PJHV)
* The rest (including all the external exceptions) are not banked, though
* they may be configurable to target either Secure or NonSecure state.
* We store the secure exception state in sec_vectors[] for the banked
* exceptions, and otherwise use only vectors[] (including for exceptions
* like SecureFault that unconditionally target Secure state).
* Entries in sec_vectors[] for non-banked exception numbers are unused.
*/
VecInfo sec_vectors[NVIC_INTERNAL_VECTORS];
/* The PRIGROUP field in AIRCR is banked */
uint32_t prigroup[M_REG_NUM_BANKS];
uint8_t num_prio_bits;
/* v8M NVIC_ITNS state (stored as a bool per bit) */
bool itns[NVIC_MAX_VECTORS];
/* The following fields are all cached state that can be recalculated
* from the vectors[] and sec_vectors[] arrays and the prigroup field:
* - vectpending
* - vectpending_is_secure
* - exception_prio
* - vectpending_prio
*/
unsigned int vectpending; /* highest prio pending enabled exception */
/* true if vectpending is a banked secure exception, ie it is in
* sec_vectors[] rather than vectors[]
*/
bool vectpending_is_s_banked;
int exception_prio; /* group prio of the highest prio active exception */
int vectpending_prio; /* group prio of the exception in vectpending */
MemoryRegion sysregmem;
uint32_t num_irq;
qemu_irq excpout;
qemu_irq sysresetreq;
};
/* Interface between CPU and Interrupt controller. */
/**
* armv7m_nvic_set_pending: mark the specified exception as pending
* @s: the NVIC
* @irq: the exception number to mark pending
* @secure: false for non-banked exceptions or for the nonsecure
* version of a banked exception, true for the secure version of a banked
* exception.
*
* Marks the specified exception as pending. Note that we will assert()
* if @secure is true and @irq does not specify one of the fixed set
* of architecturally banked exceptions.
*/
void armv7m_nvic_set_pending(NVICState *s, int irq, bool secure);
/**
* armv7m_nvic_set_pending_derived: mark this derived exception as pending
* @s: the NVIC
* @irq: the exception number to mark pending
* @secure: false for non-banked exceptions or for the nonsecure
* version of a banked exception, true for the secure version of a banked
* exception.
*
* Similar to armv7m_nvic_set_pending(), but specifically for derived
* exceptions (exceptions generated in the course of trying to take
* a different exception).
*/
void armv7m_nvic_set_pending_derived(NVICState *s, int irq, bool secure);
/**
* armv7m_nvic_set_pending_lazyfp: mark this lazy FP exception as pending
* @s: the NVIC
* @irq: the exception number to mark pending
* @secure: false for non-banked exceptions or for the nonsecure
* version of a banked exception, true for the secure version of a banked
* exception.
*
* Similar to armv7m_nvic_set_pending(), but specifically for exceptions
* generated in the course of lazy stacking of FP registers.
*/
void armv7m_nvic_set_pending_lazyfp(NVICState *s, int irq, bool secure);
/**
* armv7m_nvic_get_pending_irq_info: return highest priority pending
* exception, and whether it targets Secure state
* @s: the NVIC
* @pirq: set to pending exception number
* @ptargets_secure: set to whether pending exception targets Secure
*
* This function writes the number of the highest priority pending
* exception (the one which would be made active by
* armv7m_nvic_acknowledge_irq()) to @pirq, and sets @ptargets_secure
* to true if the current highest priority pending exception should
* be taken to Secure state, false for NS.
*/
void armv7m_nvic_get_pending_irq_info(NVICState *s, int *pirq,
bool *ptargets_secure);
/**
* armv7m_nvic_acknowledge_irq: make highest priority pending exception active
* @s: the NVIC
*
* Move the current highest priority pending exception from the pending
* state to the active state, and update v7m.exception to indicate that
* it is the exception currently being handled.
*/
void armv7m_nvic_acknowledge_irq(NVICState *s);
/**
* armv7m_nvic_complete_irq: complete specified interrupt or exception
* @s: the NVIC
* @irq: the exception number to complete
* @secure: true if this exception was secure
*
* Returns: -1 if the irq was not active
* 1 if completing this irq brought us back to base (no active irqs)
* 0 if there is still an irq active after this one was completed
* (Ignoring -1, this is the same as the RETTOBASE value before completion.)
*/
int armv7m_nvic_complete_irq(NVICState *s, int irq, bool secure);
/**
* armv7m_nvic_get_ready_status(void *opaque, int irq, bool secure)
* @s: the NVIC
* @irq: the exception number to mark pending
* @secure: false for non-banked exceptions or for the nonsecure
* version of a banked exception, true for the secure version of a banked
* exception.
*
* Return whether an exception is "ready", i.e. whether the exception is
* enabled and is configured at a priority which would allow it to
* interrupt the current execution priority. This controls whether the
* RDY bit for it in the FPCCR is set.
*/
bool armv7m_nvic_get_ready_status(NVICState *s, int irq, bool secure);
/**
* armv7m_nvic_raw_execution_priority: return the raw execution priority
* @s: the NVIC
*
* Returns: the raw execution priority as defined by the v8M architecture.
* This is the execution priority minus the effects of AIRCR.PRIS,
* and minus any PRIMASK/FAULTMASK/BASEPRI priority boosting.
* (v8M ARM ARM I_PKLD.)
*/
int armv7m_nvic_raw_execution_priority(NVICState *s);
/**
* armv7m_nvic_neg_prio_requested: return true if the requested execution
* priority is negative for the specified security state.
* @s: the NVIC
* @secure: the security state to test
* This corresponds to the pseudocode IsReqExecPriNeg().
*/
#ifndef CONFIG_USER_ONLY
bool armv7m_nvic_neg_prio_requested(NVICState *s, bool secure);
#else
static inline bool armv7m_nvic_neg_prio_requested(NVICState *s, bool secure)
{
return false;
}
#endif
#ifndef CONFIG_USER_ONLY
bool armv7m_nvic_can_take_pending_exception(NVICState *s);
#else
static inline bool armv7m_nvic_can_take_pending_exception(NVICState *s)
{
return true;
}
#endif
#endif