[PATCH 04/20] target/loongarch: Add interrupt handling support

[Song Gao <gaosong@loongson.cn>]

This patch introduces functions loongarch_cpu_do_interrupt()
and loongarch_cpu_exec_interrupt()

Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 target/loongarch/cpu.c      | 23 +++++++++++++++++++++++
 target/loongarch/internal.h | 24 ++++++++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/target/loongarch/cpu.c b/target/loongarch/cpu.c
index b368e79..c3ecc4b 100644
--- a/target/loongarch/cpu.c
+++ b/target/loongarch/cpu.c
@@ -80,6 +80,28 @@ static void loongarch_cpu_set_pc(CPUState *cs, vaddr value)
     env->active_tc.PC = value & ~(target_ulong)1;
 }
 
+bool loongarch_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
+{
+    if (interrupt_request & CPU_INTERRUPT_HARD) {
+        LoongArchCPU *cpu = LOONGARCH_CPU(cs);
+        CPULoongArchState *env = &cpu->env;
+
+        if (cpu_loongarch_hw_interrupts_enabled(env) &&
+            cpu_loongarch_hw_interrupts_pending(env)) {
+            cs->exception_index = EXCP_INTE;
+            env->error_code = 0;
+            loongarch_cpu_do_interrupt(cs);
+            return true;
+        }
+    }
+    return false;
+}
+
+void loongarch_cpu_do_interrupt(CPUState *cs)
+{
+    cs->exception_index = EXCP_NONE;
+}
+
 #ifdef CONFIG_TCG
 static void loongarch_cpu_synchronize_from_tb(CPUState *cs,
                                               const TranslationBlock *tb)
@@ -356,6 +378,7 @@ static Property loongarch_cpu_properties[] = {
 static struct TCGCPUOps loongarch_tcg_ops = {
     .initialize = loongarch_tcg_init,
     .synchronize_from_tb = loongarch_cpu_synchronize_from_tb,
+    .cpu_exec_interrupt = loongarch_cpu_exec_interrupt,
 };
 #endif /* CONFIG_TCG */
 
diff --git a/target/loongarch/internal.h b/target/loongarch/internal.h
index e2394af..09e667c 100644
--- a/target/loongarch/internal.h
+++ b/target/loongarch/internal.h
@@ -29,10 +29,34 @@ struct loongarch_def_t {
 extern const struct loongarch_def_t loongarch_defs[];
 extern const int loongarch_defs_number;
 
+void loongarch_cpu_do_interrupt(CPUState *cpu);
+bool loongarch_cpu_exec_interrupt(CPUState *cpu, int int_req);
 void loongarch_cpu_dump_state(CPUState *cpu, FILE *f, int flags);
 
 #define cpu_signal_handler cpu_loongarch_signal_handler
 
+static inline bool cpu_loongarch_hw_interrupts_enabled(CPULoongArchState *env)
+{
+    bool ret = 0;
+
+    ret = env->CSR_CRMD & (1 << CSR_CRMD_IE_SHIFT);
+
+    return ret;
+}
+
+static inline bool cpu_loongarch_hw_interrupts_pending(CPULoongArchState *env)
+{
+    int32_t pending;
+    int32_t status;
+    bool r;
+
+    pending = env->CSR_ESTAT & CSR_ESTAT_IPMASK;
+    status  = env->CSR_ECFG & CSR_ECFG_IPMASK;
+
+    r = (pending & status) != 0;
+    return r;
+}
+
 void loongarch_tcg_init(void);
 
 void QEMU_NORETURN do_raise_exception_err(CPULoongArchState *env,
-- 
1.8.3.1