target/ppc: Add do_unaligned_access hook

This allows faults from MO_ALIGN to have the same effect
as from gen_check_align.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

target/ppc/excp_helper.c

@@ -22,7 +22,7 @@
 #include "exec/helper-proto.h"
 #include "exec/exec-all.h"
 #include "exec/cpu_ldst.h"
-
+#include "internal.h"
 #include "helper_regs.h"
 
 //#define DEBUG_OP
@@ -1198,3 +1198,19 @@ void helper_book3s_msgsnd(target_ulong rb)
     qemu_mutex_unlock_iothread();
 }
 #endif
+
+void ppc_cpu_do_unaligned_access(CPUState *cs, vaddr vaddr,
+                                 MMUAccessType access_type,
+                                 int mmu_idx, uintptr_t retaddr)
+{
+    CPUPPCState *env = cs->env_ptr;
+    uint32_t insn;
+
+    /* Restore state and reload the insn we executed, for filling in DSISR.  */
+    cpu_restore_state(cs, retaddr, true);
+    insn = cpu_ldl_code(env, env->nip);
+
+    cs->exception_index = POWERPC_EXCP_ALIGN;
+    env->error_code = insn & 0x03FF0000;
+    cpu_loop_exit(cs);
+}

target/ppc/internal.h

@@ -252,4 +252,9 @@ static inline void putVSR(int n, ppc_vsr_t *vsr, CPUPPCState *env)
 void helper_compute_fprf_float16(CPUPPCState *env, float16 arg);
 void helper_compute_fprf_float32(CPUPPCState *env, float32 arg);
 void helper_compute_fprf_float128(CPUPPCState *env, float128 arg);
+
+/* Raise a data fault alignment exception for the specified virtual address */
+void ppc_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
+                                 MMUAccessType access_type,
+                                 int mmu_idx, uintptr_t retaddr);
 #endif /* PPC_INTERNAL_H */

target/ppc/translate_init.inc.c

@@ -10457,6 +10457,7 @@ static void ppc_cpu_class_init(ObjectClass *oc, void *data)
     cc->set_pc = ppc_cpu_set_pc;
     cc->gdb_read_register = ppc_cpu_gdb_read_register;
     cc->gdb_write_register = ppc_cpu_gdb_write_register;
+    cc->do_unaligned_access = ppc_cpu_do_unaligned_access;
 #ifdef CONFIG_USER_ONLY
     cc->handle_mmu_fault = ppc_cpu_handle_mmu_fault;
 #else