[PATCH v2 04/55] target/arm: Implement do_unaligned_access for user-only

[Richard Henderson <richard.henderson@linaro.org>]

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/aarch64/cpu_loop.c |  4 ++++
 linux-user/arm/cpu_loop.c     | 43 +++++++++++++++++++++++++++--------
 target/arm/cpu.c              |  2 +-
 target/arm/cpu_tcg.c          |  2 +-
 4 files changed, 40 insertions(+), 11 deletions(-)

diff --git a/linux-user/aarch64/cpu_loop.c b/linux-user/aarch64/cpu_loop.c
index ee72a1c20f..998831f87f 100644
--- a/linux-user/aarch64/cpu_loop.c
+++ b/linux-user/aarch64/cpu_loop.c
@@ -137,6 +137,10 @@ void cpu_loop(CPUARMState *env)
             case 0x11: /* Synchronous Tag Check Fault */
                 info.si_code = TARGET_SEGV_MTESERR;
                 break;
+            case 0x21: /* Alignment fault */
+                info.si_signo = TARGET_SIGBUS;
+                info.si_code = TARGET_BUS_ADRALN;
+                break;
             default:
                 g_assert_not_reached();
             }
diff --git a/linux-user/arm/cpu_loop.c b/linux-user/arm/cpu_loop.c
index 69632d15be..da7da6a0c1 100644
--- a/linux-user/arm/cpu_loop.c
+++ b/linux-user/arm/cpu_loop.c
@@ -23,6 +23,7 @@
 #include "elf.h"
 #include "cpu_loop-common.h"
 #include "semihosting/common-semi.h"
+#include "target/arm/syndrome.h"
 
 #define get_user_code_u32(x, gaddr, env)                \
     ({ abi_long __r = get_user_u32((x), (gaddr));       \
@@ -286,9 +287,8 @@ void cpu_loop(CPUARMState *env)
 {
     CPUState *cs = env_cpu(env);
     int trapnr;
-    unsigned int n, insn;
+    unsigned int n, insn, ec, fsc;
     target_siginfo_t info;
-    uint32_t addr;
     abi_ulong ret;
 
     for(;;) {
@@ -437,15 +437,40 @@ void cpu_loop(CPUARMState *env)
             break;
         case EXCP_PREFETCH_ABORT:
         case EXCP_DATA_ABORT:
-            addr = env->exception.vaddress;
-            {
-                info.si_signo = TARGET_SIGSEGV;
-                info.si_errno = 0;
-                /* XXX: check env->error_code */
+            info.si_signo = TARGET_SIGSEGV;
+            info.si_errno = 0;
+            info._sifields._sigfault._addr = env->exception.vaddress;
+            /*
+             * We should only arrive here with EC in {DATAABORT, INSNABORT},
+             * and short-form FSC, which then tells us to look at the FSR.
+             * ??? arm_cpu_reset never sets TTBCR_EAE, so we always get
+             * short-form FSC.
+             */
+            ec = syn_get_ec(env->exception.syndrome);
+            assert(ec == EC_DATAABORT || ec == EC_INSNABORT);
+            fsc = extract32(env->exception.syndrome, 0, 6);
+            assert(fsc == 0x3f);
+            switch (env->exception.fsr & 0x1f) {
+            case 0x1: /* Alignment */
+                info.si_signo = TARGET_SIGBUS;
+                info.si_code = TARGET_BUS_ADRALN;
+                break;
+            case 0x3: /* Access flag fault, level 1 */
+            case 0x6: /* Access flag fault, level 2 */
+            case 0x9: /* Domain fault, level 1 */
+            case 0xb: /* Domain fault, level 2 */
+            case 0xd: /* Permision fault, level 1 */
+            case 0xf: /* Permision fault, level 2 */
+                info.si_code = TARGET_SEGV_ACCERR;
+                break;
+            case 0x5: /* Translation fault, level 1 */
+            case 0x7: /* Translation fault, level 2 */
                 info.si_code = TARGET_SEGV_MAPERR;
-                info._sifields._sigfault._addr = addr;
-                queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
+                break;
+            default:
+                g_assert_not_reached();
             }
+            queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info);
             break;
         case EXCP_DEBUG:
         case EXCP_BKPT:
diff --git a/target/arm/cpu.c b/target/arm/cpu.c
index 2866dd7658..de0d968d76 100644
--- a/target/arm/cpu.c
+++ b/target/arm/cpu.c
@@ -1987,11 +1987,11 @@ static const struct TCGCPUOps arm_tcg_ops = {
     .cpu_exec_interrupt = arm_cpu_exec_interrupt,
     .tlb_fill = arm_cpu_tlb_fill,
     .debug_excp_handler = arm_debug_excp_handler,
+    .do_unaligned_access = arm_cpu_do_unaligned_access,
 
 #if !defined(CONFIG_USER_ONLY)
     .do_interrupt = arm_cpu_do_interrupt,
     .do_transaction_failed = arm_cpu_do_transaction_failed,
-    .do_unaligned_access = arm_cpu_do_unaligned_access,
     .adjust_watchpoint_address = arm_adjust_watchpoint_address,
     .debug_check_watchpoint = arm_debug_check_watchpoint,
     .debug_check_breakpoint = arm_debug_check_breakpoint,
diff --git a/target/arm/cpu_tcg.c b/target/arm/cpu_tcg.c
index ed444bf436..1b91fdc890 100644
--- a/target/arm/cpu_tcg.c
+++ b/target/arm/cpu_tcg.c
@@ -904,11 +904,11 @@ static const struct TCGCPUOps arm_v7m_tcg_ops = {
     .cpu_exec_interrupt = arm_v7m_cpu_exec_interrupt,
     .tlb_fill = arm_cpu_tlb_fill,
     .debug_excp_handler = arm_debug_excp_handler,
+    .do_unaligned_access = arm_cpu_do_unaligned_access,
 
 #if !defined(CONFIG_USER_ONLY)
     .do_interrupt = arm_v7m_cpu_do_interrupt,
     .do_transaction_failed = arm_cpu_do_transaction_failed,
-    .do_unaligned_access = arm_cpu_do_unaligned_access,
     .adjust_watchpoint_address = arm_adjust_watchpoint_address,
     .debug_check_watchpoint = arm_debug_check_watchpoint,
     .debug_check_breakpoint = arm_debug_check_breakpoint,
-- 
2.25.1