7 files changed, 42 insertions, 3 deletions

diff --git a/target/hppa/cpu.c b/target/hppa/cpu.c
index 23eb254228..37b763fca0 100644
--- a/target/hppa/cpu.c
+++ b/target/hppa/cpu.c
@@ -62,7 +62,7 @@ static void hppa_cpu_synchronize_from_tb(CPUState *cs,
 
 static bool hppa_cpu_has_work(CPUState *cs)
 {
-    return cs->interrupt_request & CPU_INTERRUPT_HARD;
+    return cs->interrupt_request & (CPU_INTERRUPT_HARD | CPU_INTERRUPT_NMI);
 }
 
 static void hppa_cpu_disas_set_info(CPUState *cs, disassemble_info *info)
diff --git a/target/hppa/cpu.h b/target/hppa/cpu.h
index 45fd338b02..93c119532a 100644
--- a/target/hppa/cpu.h
+++ b/target/hppa/cpu.h
@@ -69,6 +69,11 @@
 #define EXCP_SYSCALL             30
 #define EXCP_SYSCALL_LWS         31
 
+/* Emulated hardware TOC button */
+#define EXCP_TOC                 32 /* TOC = Transfer of control (NMI) */
+
+#define CPU_INTERRUPT_NMI       CPU_INTERRUPT_TGT_EXT_3         /* TOC */
+
 /* Taken from Linux kernel: arch/parisc/include/asm/psw.h */
 #define PSW_I            0x00000001
 #define PSW_D            0x00000002
diff --git a/target/hppa/helper.h b/target/hppa/helper.h
index 0a629ffa7c..fe8a9ce493 100644
--- a/target/hppa/helper.h
+++ b/target/hppa/helper.h
@@ -80,6 +80,7 @@ DEF_HELPER_FLAGS_0(read_interval_timer, TCG_CALL_NO_RWG, tr)
 #ifndef CONFIG_USER_ONLY
 DEF_HELPER_1(halt, noreturn, env)
 DEF_HELPER_1(reset, noreturn, env)
+DEF_HELPER_1(getshadowregs, void, env)
 DEF_HELPER_1(rfi, void, env)
 DEF_HELPER_1(rfi_r, void, env)
 DEF_HELPER_FLAGS_2(write_interval_timer, TCG_CALL_NO_RWG, void, env, tr)
diff --git a/target/hppa/insns.decode b/target/hppa/insns.decode
index d4eefc0d48..c7a7e997f9 100644
--- a/target/hppa/insns.decode
+++ b/target/hppa/insns.decode
@@ -111,6 +111,7 @@ rfi_r           000000 ----- ----- --- 01100101 00000
 # They are allocated from the unassigned instruction space.
 halt            1111 1111 1111 1101 1110 1010 1101 0000
 reset           1111 1111 1111 1101 1110 1010 1101 0001
+getshadowregs   1111 1111 1111 1101 1110 1010 1101 0010
 
 ####
 # Memory Management
diff --git a/target/hppa/int_helper.c b/target/hppa/int_helper.c
index 13073ae2bd..f599dccfff 100644
--- a/target/hppa/int_helper.c
+++ b/target/hppa/int_helper.c
@@ -23,6 +23,7 @@
 #include "cpu.h"
 #include "exec/helper-proto.h"
 #include "hw/core/cpu.h"
+#include "hw/hppa/hppa_hardware.h"
 
 #ifndef CONFIG_USER_ONLY
 static void eval_interrupt(HPPACPU *cpu)
@@ -181,7 +182,14 @@ void hppa_cpu_do_interrupt(CPUState *cs)
     }
 
     /* step 7 */
-    env->iaoq_f = env->cr[CR_IVA] + 32 * i;
+    if (i == EXCP_TOC) {
+        env->iaoq_f = FIRMWARE_START;
+        /* help SeaBIOS and provide iaoq_b and iasq_back in shadow regs */
+        env->gr[24] = env->cr_back[0];
+        env->gr[25] = env->cr_back[1];
+    } else {
+        env->iaoq_f = env->cr[CR_IVA] + 32 * i;
+    }
     env->iaoq_b = env->iaoq_f + 4;
     env->iasq_f = 0;
     env->iasq_b = 0;
@@ -219,6 +227,7 @@ void hppa_cpu_do_interrupt(CPUState *cs)
             [EXCP_PER_INTERRUPT] = "performance monitor interrupt",
             [EXCP_SYSCALL]       = "syscall",
             [EXCP_SYSCALL_LWS]   = "syscall-lws",
+            [EXCP_TOC]           = "TOC (transfer of control)",
         };
         static int count;
         const char *name = NULL;
@@ -248,6 +257,14 @@ bool hppa_cpu_exec_interrupt(CPUState *cs, int interrupt_request)
     HPPACPU *cpu = HPPA_CPU(cs);
     CPUHPPAState *env = &cpu->env;
 
+    if (interrupt_request & CPU_INTERRUPT_NMI) {
+        /* Raise TOC (NMI) interrupt */
+        cpu_reset_interrupt(cs, CPU_INTERRUPT_NMI);
+        cs->exception_index = EXCP_TOC;
+        hppa_cpu_do_interrupt(cs);
+        return true;
+    }
+
     /* If interrupts are requested and enabled, raise them.  */
     if ((env->psw & PSW_I) && (interrupt_request & CPU_INTERRUPT_HARD)) {
         cs->exception_index = EXCP_EXT_INTERRUPT;
diff --git a/target/hppa/op_helper.c b/target/hppa/op_helper.c
index 1b86557d5d..b0dec4ebf4 100644
--- a/target/hppa/op_helper.c
+++ b/target/hppa/op_helper.c
@@ -694,7 +694,7 @@ void HELPER(rfi)(CPUHPPAState *env)
     cpu_hppa_put_psw(env, env->cr[CR_IPSW]);
 }
 
-void HELPER(rfi_r)(CPUHPPAState *env)
+void HELPER(getshadowregs)(CPUHPPAState *env)
 {
     env->gr[1] = env->shadow[0];
     env->gr[8] = env->shadow[1];
@@ -703,6 +703,11 @@ void HELPER(rfi_r)(CPUHPPAState *env)
     env->gr[17] = env->shadow[4];
     env->gr[24] = env->shadow[5];
     env->gr[25] = env->shadow[6];
+}
+
+void HELPER(rfi_r)(CPUHPPAState *env)
+{
+    helper_getshadowregs(env);
     helper_rfi(env);
 }
 #endif
diff --git a/target/hppa/translate.c b/target/hppa/translate.c
index c6195590f8..5c0b1eb274 100644
--- a/target/hppa/translate.c
+++ b/target/hppa/translate.c
@@ -2393,6 +2393,16 @@ static bool trans_reset(DisasContext *ctx, arg_reset *a)
 #endif
 }
 
+static bool trans_getshadowregs(DisasContext *ctx, arg_getshadowregs *a)
+{
+    CHECK_MOST_PRIVILEGED(EXCP_PRIV_OPR);
+#ifndef CONFIG_USER_ONLY
+    nullify_over(ctx);
+    gen_helper_getshadowregs(cpu_env);
+    return nullify_end(ctx);
+#endif
+}
+
 static bool trans_nop_addrx(DisasContext *ctx, arg_ldst *a)
 {
     if (a->m) {