PPC_INTERRUPT_EBB is a new interrupt that will be used to deliver EBB
exceptions that had to be postponed because the thread wasn't in problem
state at the time the event-based branch was supposed to occur.
ISA 3.1 also defines two EBB exceptions: Performance Monitor EBB
exception and External EBB exception. They are being added as
POWERPC_EXCP_PERFM_EBB and POWERPC_EXCP_EXTERNAL_EBB.
PPC_INTERRUPT_EBB will check BESCR bits to see the EBB type that
occurred and trigger the appropriate exception. Both exceptions are
doing the same thing in this first implementation: clear BESCR_GE and
enter the branch with env->nip retrieved from SPR_EBBHR.
The checks being done by the interrupt code are msr_pr and BESCR_GE
states. All other checks (EBB facility check, BESCR_PME bit, specific
bits related to the event type) must be done beforehand.
Signed-off-by: Daniel Henrique Barboza <danielhb...@gmail.com>
---
target/ppc/cpu.h | 5 ++++-
target/ppc/cpu_init.c | 4 ++++
target/ppc/excp_helper.c | 33 +++++++++++++++++++++++++++++++++
3 files changed, 41 insertions(+), 1 deletion(-)
diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h
index dcd83b503c..3962c8f6f4 100644
--- a/target/ppc/cpu.h
+++ b/target/ppc/cpu.h
@@ -129,8 +129,10 @@ enum {
/* ISA 3.00 additions */
POWERPC_EXCP_HVIRT = 101,
POWERPC_EXCP_SYSCALL_VECTORED = 102, /* scv exception
*/
+ POWERPC_EXCP_PERFM_EBB = 103, /* Performance Monitor EBB Exception */
+ POWERPC_EXCP_EXTERNAL_EBB = 104, /* External EBB Exception */
/* EOL */
- POWERPC_EXCP_NB = 103,
+ POWERPC_EXCP_NB = 105,
/* QEMU exceptions: special cases we want to stop translation */
POWERPC_EXCP_SYSCALL_USER = 0x203, /* System call in user mode only */
};
@@ -2453,6 +2455,7 @@ enum {
PPC_INTERRUPT_HMI, /* Hypervisor Maintenance interrupt */
PPC_INTERRUPT_HDOORBELL, /* Hypervisor Doorbell interrupt */
PPC_INTERRUPT_HVIRT, /* Hypervisor virtualization interrupt */
+ PPC_INTERRUPT_EBB, /* Event-based Branch exception */
};
/* Processor Compatibility mask (PCR) */
diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c
index bf60529d37..136d8ca8b5 100644
--- a/target/ppc/cpu_init.c
+++ b/target/ppc/cpu_init.c
@@ -2336,6 +2336,10 @@ static void init_excp_POWER8(CPUPPCState *env)
env->excp_vectors[POWERPC_EXCP_FU] = 0x00000F60;
env->excp_vectors[POWERPC_EXCP_HV_FU] = 0x00000F80;
env->excp_vectors[POWERPC_EXCP_SDOOR_HV] = 0x00000E80;
+
+ /* Userland exceptions without vector value in PowerISA v3.1 */
+ env->excp_vectors[POWERPC_EXCP_PERFM_EBB] = 0x0;
+ env->excp_vectors[POWERPC_EXCP_EXTERNAL_EBB] = 0x0;
#endif
}
diff --git a/target/ppc/excp_helper.c b/target/ppc/excp_helper.c
index 8a49a4ab90..ad40a0f8e6 100644
--- a/target/ppc/excp_helper.c
+++ b/target/ppc/excp_helper.c
@@ -990,6 +990,21 @@ static void powerpc_excp_books(PowerPCCPU *cpu, int excp)
new_msr |= (target_ulong)MSR_HVB;
new_msr |= env->msr & ((target_ulong)1 << MSR_RI);
break;
+ case POWERPC_EXCP_PERFM_EBB: /* Performance Monitor EBB Exception
*/
+ case POWERPC_EXCP_EXTERNAL_EBB: /* External EBB Exception
*/
+ env->spr[SPR_BESCR] &= ~BESCR_GE;
+
+ /*
+ * Save NIP for rfebb insn in SPR_EBBRR. Next nip is
+ * stored in the EBB Handler SPR_EBBHR.
+ */
+ env->spr[SPR_EBBRR] = env->nip;
+ powerpc_set_excp_state(cpu, env->spr[SPR_EBBHR], env->msr);
+
+ /*
+ * This exception is handled in userspace. No need to proceed.
+ */
+ return;
case POWERPC_EXCP_THERM: /* Thermal interrupt */
case POWERPC_EXCP_PERFM: /* Embedded performance monitor interrupt */
case POWERPC_EXCP_VPUA: /* Vector assist exception */
@@ -1681,6 +1696,24 @@ static void ppc_hw_interrupt(CPUPPCState *env)
powerpc_excp(cpu, POWERPC_EXCP_THERM);
return;
}
+ /* EBB exception */
+ if (env->pending_interrupts & (1 << PPC_INTERRUPT_EBB)) {
+ /*
+ * EBB exception must be taken in problem state and
+ * with BESCR_GE set.
+ */
+ if (msr_pr == 1 && env->spr[SPR_BESCR] & BESCR_GE) {
+ env->pending_interrupts &= ~(1 << PPC_INTERRUPT_EBB);
+
+ if (env->spr[SPR_BESCR] & BESCR_PMEO) {
+ powerpc_excp(cpu, POWERPC_EXCP_PERFM_EBB);
+ } else if (env->spr[SPR_BESCR] & BESCR_EEO) {
+ powerpc_excp(cpu, POWERPC_EXCP_EXTERNAL_EBB);
+ }
+
+ return;
+ }
+ }
}
if (env->resume_as_sreset) {
--
2.34.1
