From 56e9d7c09eba41b77357ebaa6592a7f30587e1ff Mon Sep 17 00:00:00 2001
From: Peter Maydell <peter.maydell@linaro.org>
Date: Fri, 23 Feb 2018 20:02:54 -0500
Subject: [PATCH] target-arm: Split data abort syndrome generator

Split the data abort syndrome generator into two versions:
One with a valid Instruction Specific Syndrome (ISS) and another without.

The following new flags are supported by the syndrome generator
with ISS:
* isv - Instruction syndrome valid
* sas - Syndrome access size
* sse - Syndrome sign extend
* srt - Syndrome register transfer
* sf - Sixty-Four bit register width
* ar - Acquire/Release

These flags are not yet used, so this patch has no functional change
except that we will now correctly set the IL bit in data abort
syndromes without ISS information.

Backports commit 094d028a7968236cd2b7f7b96394f7a3b8ad97c8 from qemu
---
 qemu/target-arm/internals.h | 24 +++++++++++++++++++++---
 qemu/target-arm/op_helper.c |  6 ++++--
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/qemu/target-arm/internals.h b/qemu/target-arm/internals.h
index c97bff34..73b45a81 100644
--- a/qemu/target-arm/internals.h
+++ b/qemu/target-arm/internals.h
@@ -266,7 +266,9 @@ enum arm_exception_class {
 
 #define ARM_EL_EC_SHIFT 26
 #define ARM_EL_IL_SHIFT 25
+#define ARM_EL_ISV_SHIFT 24
 #define ARM_EL_IL (1 << ARM_EL_IL_SHIFT)
+#define ARM_EL_ISV (1 << ARM_EL_ISV_SHIFT)
 
 /* Utility functions for constructing various kinds of syndrome value.
  * Note that in general we follow the AArch64 syndrome values; in a
@@ -386,11 +388,27 @@ static inline uint32_t syn_insn_abort(int same_el, int ea, int s1ptw, int fsc)
         | (ea << 9) | (s1ptw << 7) | fsc;
 }
 
-static inline uint32_t syn_data_abort(int same_el, int ea, int cm, int s1ptw,
-                                      int wnr, int fsc)
+static inline uint32_t syn_data_abort_no_iss(int same_el,
+                                             int ea, int cm, int s1ptw,
+                                             int wnr, int fsc)
 {
     return (EC_DATAABORT << ARM_EL_EC_SHIFT) | (same_el << ARM_EL_EC_SHIFT)
-        | (ea << 9) | (cm << 8) | (s1ptw << 7) | (wnr << 6) | fsc;
+           | ARM_EL_IL
+           | (ea << 9) | (cm << 8) | (s1ptw << 7) | (wnr << 6) | fsc;
+}
+
+static inline uint32_t syn_data_abort_with_iss(int same_el,
+                                               int sas, int sse, int srt,
+                                               int sf, int ar,
+                                               int ea, int cm, int s1ptw,
+                                               int wnr, int fsc,
+                                               bool is_16bit)
+{
+    return (EC_DATAABORT << ARM_EL_EC_SHIFT) | (same_el << ARM_EL_EC_SHIFT)
+           | (is_16bit ? 0 : ARM_EL_IL)
+           | ARM_EL_ISV | (sas << 22) | (sse << 21) | (srt << 16)
+           | (sf << 15) | (ar << 14)
+           | (ea << 9) | (cm << 8) | (s1ptw << 7) | (wnr << 6) | fsc;
 }
 
 static inline uint32_t syn_swstep(int same_el, int isv, int ex)
diff --git a/qemu/target-arm/op_helper.c b/qemu/target-arm/op_helper.c
index 98a82b32..9e54cc47 100644
--- a/qemu/target-arm/op_helper.c
+++ b/qemu/target-arm/op_helper.c
@@ -115,7 +115,8 @@ void tlb_fill(CPUState *cs, target_ulong addr, int is_write, int mmu_idx,
             syn = syn_insn_abort(same_el, 0, fi.s1ptw, syn);
             exc = EXCP_PREFETCH_ABORT;
         } else {
-            syn = syn_data_abort(same_el, 0, 0, fi.s1ptw, is_write == 1, syn);
+            syn = syn_data_abort_no_iss(same_el,
+                                        0, 0, fi.s1ptw, is_write == 1, syn);
             if (is_write == 1 && arm_feature(env, ARM_FEATURE_V6)) {
                 fsr |= (1 << 11);
             }
@@ -161,7 +162,8 @@ void arm_cpu_do_unaligned_access(CPUState *cs, vaddr vaddr, int is_write,
     }
 
     raise_exception(env, EXCP_DATA_ABORT,
-                    syn_data_abort(same_el, 0, 0, 0, is_write == 1, 0x21),
+                    syn_data_abort_no_iss(same_el,
+                                          0, 0, 0, is_write == 1, 0x21),
                     target_el);
 }