Implement Configuration and Control register.
Handle STACKALIGN and USERSETMPEND bits.
---
hw/intc/armv7m_nvic.c | 15 +++++++++++----
target-arm/cpu.h | 1 +
target-arm/helper.c | 8 +++-----
target-arm/machine.c | 1 +
4 files changed, 16 insertions(+), 9 deletions(-)
diff --git a/hw/intc/armv7m_nvic.c b/hw/intc/armv7m_nvic.c
index 7d261ae..0f9ca6a 100644
--- a/hw/intc/armv7m_nvic.c
+++ b/hw/intc/armv7m_nvic.c
@@ -534,8 +534,7 @@ static uint32_t nvic_readl(NVICState *s, uint32_t offset)
/* TODO: Implement SLEEPONEXIT. */
return 0;
case 0xd14: /* Configuration Control. */
- /* TODO: Implement Configuration Control bits. */
- return 0;
+ return cpu->env.v7m.ccr;
case 0xd24: /* System Handler Status. */
val = 0;
if (s->vectors[ARMV7M_EXCP_MEM].active) val |= (1 << 0);
@@ -685,9 +684,17 @@ static void nvic_writel(NVICState *s, uint32_t offset,
uint32_t value)
}
break;
case 0xd10: /* System Control. */
- case 0xd14: /* Configuration Control. */
/* TODO: Implement control registers. */
- qemu_log_mask(LOG_UNIMP, "NVIC: SCR and CCR unimplemented\n");
+ qemu_log_mask(LOG_UNIMP, "NVIC: SCR unimplemented\n");
+ break;
+ case 0xd14: /* Configuration Control. */
+ value &= 0x31b;
+ if (value & 0x118) {
+ qemu_log_mask(LOG_UNIMP, "CCR unimplemented bits"
+ " BFHFNMIGN, DIV_0_TRP, UNALIGN_TRP");
+ value &= ~0x118;
+ }
+ cpu->env.v7m.ccr = value;
break;
case 0xd24: /* System Handler Control. */
/* TODO: Real hardware allows you to set/clear the active bits
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index b98ef89..4e1b8cf 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -396,6 +396,7 @@ typedef struct CPUARMState {
uint32_t vecbase;
uint32_t basepri;
uint32_t control;
+ uint32_t ccr; /* Configuration and Control */
uint32_t cfsr; /* Configurable Fault Status */
uint32_t hfsr; /* HardFault Status */
uint32_t mmfar; /* MemManage Fault Address */
diff --git a/target-arm/helper.c b/target-arm/helper.c
index f7e496d..17d1ca0 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -5412,7 +5412,7 @@ static void do_v7m_exception_exit(CPUARMState *env)
break;
case 0x9: /* Return to Thread mode w/ Main stack */
case 0xd: /* Return to Thread mode w/ Process stack */
- if (env->v7m.exception_prio != 0x100) {
+ if ((env->v7m.exception_prio != 0x100) && !(env->v7m.ccr & 1)) {
/* Attempt to return to Thread mode
* from nested handler while NONBASETHRDENA not set.
*/
@@ -5582,10 +5582,8 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs)
qemu_log_mask(CPU_LOG_INT, "... as %d\n", env->v7m.exception);
- /* Align stack pointer. */
- /* ??? Should only do this if Configuration Control Register
- STACKALIGN bit is set. */
- if (env->regs[13] & 4) {
+ /* Align stack pointer (STACKALIGN) */
+ if ((env->regs[13] & 4) && (env->v7m.ccr & (1<<9))) {
env->regs[13] -= 4;
xpsr |= 0x200;
}
diff --git a/target-arm/machine.c b/target-arm/machine.c
index 14a4882..7aee41e 100644
--- a/target-arm/machine.c
+++ b/target-arm/machine.c
@@ -100,6 +100,7 @@ static const VMStateDescription vmstate_m = {
VMSTATE_UINT32(env.v7m.vecbase, ARMCPU),
VMSTATE_UINT32(env.v7m.basepri, ARMCPU),
VMSTATE_UINT32(env.v7m.control, ARMCPU),
+ VMSTATE_UINT32(env.v7m.ccr, ARMCPU),
VMSTATE_UINT32(env.v7m.cfsr, ARMCPU),
VMSTATE_UINT32(env.v7m.hfsr, ARMCPU),
VMSTATE_UINT32(env.v7m.mmfar, ARMCPU),
--
2.1.4
