diff options
Diffstat (limited to 'hw/intc/armv7m_nvic.c')
-rw-r--r-- | hw/intc/armv7m_nvic.c | 59 |
1 files changed, 32 insertions, 27 deletions
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c index 6f94f88a79..cf233c0561 100644 --- a/hw/intc/armv7m_nvic.c +++ b/hw/intc/armv7m_nvic.c @@ -832,10 +832,40 @@ int armv7m_nvic_complete_irq(void *opaque, int irq, bool secure) { NVICState *s = (NVICState *)opaque; VecInfo *vec = NULL; - int ret; + int ret = 0; assert(irq > ARMV7M_EXCP_RESET && irq < s->num_irq); + trace_nvic_complete_irq(irq, secure); + + if (secure && exc_is_banked(irq)) { + vec = &s->sec_vectors[irq]; + } else { + vec = &s->vectors[irq]; + } + + /* + * Identify illegal exception return cases. We can't immediately + * return at this point because we still need to deactivate + * (either this exception or NMI/HardFault) first. + */ + if (!exc_is_banked(irq) && exc_targets_secure(s, irq) != secure) { + /* + * Return from a configurable exception targeting the opposite + * security state from the one we're trying to complete it for. + * Clear vec because it's not really the VecInfo for this + * (irq, secstate) so we mustn't deactivate it. + */ + ret = -1; + vec = NULL; + } else if (!vec->active) { + /* Return from an inactive interrupt */ + ret = -1; + } else { + /* Legal return, we will return the RETTOBASE bit value to the caller */ + ret = nvic_rettobase(s); + } + /* * For negative priorities, v8M will forcibly deactivate the appropriate * NMI or HardFault regardless of what interrupt we're being asked to @@ -865,32 +895,7 @@ int armv7m_nvic_complete_irq(void *opaque, int irq, bool secure) } if (!vec) { - if (secure && exc_is_banked(irq)) { - vec = &s->sec_vectors[irq]; - } else { - vec = &s->vectors[irq]; - } - } - - trace_nvic_complete_irq(irq, secure); - - if (!vec->active) { - /* Tell the caller this was an illegal exception return */ - return -1; - } - - /* - * If this is a configurable exception and it is currently - * targeting the opposite security state from the one we're trying - * to complete it for, this counts as an illegal exception return. - * We still need to deactivate whatever vector the logic above has - * selected, though, as it might not be the same as the one for the - * requested exception number. - */ - if (!exc_is_banked(irq) && exc_targets_secure(s, irq) != secure) { - ret = -1; - } else { - ret = nvic_rettobase(s); + return ret; } vec->active = 0; |