Re: [PATCH v5 09/11] target/loongarch: CPU enable msg interrupts.

[Bibo Mao]

On 2025/7/11 下午4:59, Song Gao wrote:

when loongarch cpu set irq is INT_AVEC, we need set CSR_ESTAT.MSGINT bit.

Signed-off-by: Song Gao <gaos...@loongson.cn>
---
  target/loongarch/cpu-csr.h |  6 ++++--
  target/loongarch/cpu.c     | 10 +++++++++-
  2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/target/loongarch/cpu-csr.h b/target/loongarch/cpu-csr.h
index 4792677086..6ec13d13d1 100644
--- a/target/loongarch/cpu-csr.h
+++ b/target/loongarch/cpu-csr.h
@@ -34,11 +34,13 @@ FIELD(CSR_MISC, ALCL, 12, 4)
  FIELD(CSR_MISC, DWPL, 16, 3)

#define LOONGARCH_CSR_ECFG 0x4 /* Exception config */

-FIELD(CSR_ECFG, LIE, 0, 13)
+FIELD(CSR_ECFG, LIE, 0, 15)        /*bit 15 is msg interrupt enabled */
+FIELD(CSR_ECFG, MSGINT, 14, 1)
  FIELD(CSR_ECFG, VS, 16, 3)

#define LOONGARCH_CSR_ESTAT 0x5 /* Exception status */

-FIELD(CSR_ESTAT, IS, 0, 13)
+FIELD(CSR_ESTAT, IS, 0, 15)        /*bit 15 is msg interrupt enabled */
+FIELD(CSR_ESTAT, MSGINT, 14, 1)
  FIELD(CSR_ESTAT, ECODE, 16, 6)
  FIELD(CSR_ESTAT, ESUBCODE, 22, 9)

diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c

index abad84c054..9e21ed1d07 100644
--- a/target/loongarch/cpu.c
+++ b/target/loongarch/cpu.c
@@ -130,7 +130,15 @@ void loongarch_cpu_set_irq(void *opaque, int irq, int 
level)
      if (kvm_enabled()) {
          kvm_loongarch_set_interrupt(cpu, irq, level);
      } else if (tcg_enabled()) {
-        env->CSR_ESTAT = deposit64(env->CSR_ESTAT, irq, 1, level != 0);
+        /* do INTC_AVEC irqs */
+        if (irq == INT_AVEC) {
+            irq = find_first_bit(env->CSR_MSGIS, 256);
+            if (irq < 256) {
+                env->CSR_ESTAT = FIELD_DP64(env->CSR_ESTAT, CSR_ESTAT, MSGINT, 
1);
+            }

Why is there such checking for bitmap? Can the original sentence work?
  env->CSR_ESTAT = deposit64(env->CSR_ESTAT, irq, 1, level != 0);

This piece of code is a little strange.

Regards
Bibo Mao

+        } else {
+            env->CSR_ESTAT = deposit64(env->CSR_ESTAT, irq, 1, level != 0);
+        }
          if (FIELD_EX64(env->CSR_ESTAT, CSR_ESTAT, IS)) {
              cpu_interrupt(cs, CPU_INTERRUPT_HARD);
          } else {