[Qemu-devel] [PATCH v1 04/17] target-arm: implement SCTLR.EE

[Peter Crosthwaite]

From: Peter Crosthwaite <address@hidden>

Implement SCTLR.EE bit which controls data endianess for exceptions
and page table translations. SCTLR.EE is mirrored to the CPSR.E bit
on exception entry.

Signed-off-by: Peter Crosthwaite <address@hidden>
---

 target-arm/helper.c | 42 ++++++++++++++++++++++++++++++++----------
 1 file changed, 32 insertions(+), 10 deletions(-)

diff --git a/target-arm/helper.c b/target-arm/helper.c
index 59d5a41..afac1b2 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -5889,7 +5889,10 @@ void arm_cpu_do_interrupt(CPUState *cs)
     /* Clear IT bits.  */
     env->condexec_bits = 0;
     /* Switch to the new mode, and to the correct instruction set.  */
-    env->uncached_cpsr = (env->uncached_cpsr & ~CPSR_M) | new_mode;
+    env->uncached_cpsr = (env->uncached_cpsr & ~(CPSR_M)) | new_mode;
+    /* Set new mode endianess */
+    env->uncached_cpsr = (env->uncached_cpsr & ~(CPSR_E)) |
+        (env->cp15.sctlr_el[arm_current_el(env)] & SCTLR_EE ? CPSR_E : 0);
     env->daif |= mask;
     /* this is a lie, as the was no c1_sys on V4T/V5, but who cares
      * and we should just guard the thumb mode on V4 */
@@ -5958,6 +5961,12 @@ static inline bool 
regime_translation_disabled(CPUARMState *env,
     return (regime_sctlr(env, mmu_idx) & SCTLR_M) == 0;
 }
 
+static inline bool regime_translation_big_endian(CPUARMState *env,
+                                                 ARMMMUIdx mmu_idx)
+{
+    return (regime_sctlr(env, mmu_idx) & SCTLR_EE) != 0;
+}
+
 /* Return the TCR controlling this translation regime */
 static inline TCR *regime_tcr(CPUARMState *env, ARMMMUIdx mmu_idx)
 {
@@ -6263,7 +6272,7 @@ static hwaddr S1_ptw_translate(CPUARMState *env, 
ARMMMUIdx mmu_idx,
  */
 static uint32_t arm_ldl_ptw(CPUState *cs, hwaddr addr, bool is_secure,
                             ARMMMUIdx mmu_idx, uint32_t *fsr,
-                            ARMMMUFaultInfo *fi)
+                            ARMMMUFaultInfo *fi, bool be)
 {
     ARMCPU *cpu = ARM_CPU(cs);
     CPUARMState *env = &cpu->env;
@@ -6274,12 +6283,16 @@ static uint32_t arm_ldl_ptw(CPUState *cs, hwaddr addr, 
bool is_secure,
     if (fi->s1ptw) {
         return 0;
     }
-    return address_space_ldl(cs->as, addr, attrs, NULL);
+    if (be) {
+        return address_space_ldl_be(cs->as, addr, attrs, NULL);
+    } else {
+        return address_space_ldl_le(cs->as, addr, attrs, NULL);
+    }
 }
 
 static uint64_t arm_ldq_ptw(CPUState *cs, hwaddr addr, bool is_secure,
                             ARMMMUIdx mmu_idx, uint32_t *fsr,
-                            ARMMMUFaultInfo *fi)
+                            ARMMMUFaultInfo *fi, bool be)
 {
     ARMCPU *cpu = ARM_CPU(cs);
     CPUARMState *env = &cpu->env;
@@ -6290,7 +6303,11 @@ static uint64_t arm_ldq_ptw(CPUState *cs, hwaddr addr, 
bool is_secure,
     if (fi->s1ptw) {
         return 0;
     }
-    return address_space_ldq(cs->as, addr, attrs, NULL);
+    if (be) {
+        return address_space_ldq_be(cs->as, addr, attrs, NULL);
+    } else {
+        return address_space_ldq_le(cs->as, addr, attrs, NULL);
+    }
 }
 
 static bool get_phys_addr_v5(CPUARMState *env, uint32_t address,
@@ -6318,7 +6335,8 @@ static bool get_phys_addr_v5(CPUARMState *env, uint32_t 
address,
         goto do_fault;
     }
     desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx),
-                       mmu_idx, fsr, fi);
+                       mmu_idx, fsr, fi,
+                       regime_translation_big_endian(env, mmu_idx));
     type = (desc & 3);
     domain = (desc >> 5) & 0x0f;
     if (regime_el(env, mmu_idx) == 1) {
@@ -6355,7 +6373,8 @@ static bool get_phys_addr_v5(CPUARMState *env, uint32_t 
address,
             table = (desc & 0xfffff000) | ((address >> 8) & 0xffc);
         }
         desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx),
-                           mmu_idx, fsr, fi);
+                           mmu_idx, fsr, fi,
+                           regime_translation_big_endian(env, mmu_idx));
         switch (desc & 3) {
         case 0: /* Page translation fault.  */
             code = 7;
@@ -6437,7 +6456,8 @@ static bool get_phys_addr_v6(CPUARMState *env, uint32_t 
address,
         goto do_fault;
     }
     desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx),
-                       mmu_idx, fsr, fi);
+                       mmu_idx, fsr, fi,
+                       regime_translation_big_endian(env, mmu_idx));
     type = (desc & 3);
     if (type == 0 || (type == 3 && !arm_feature(env, ARM_FEATURE_PXN))) {
         /* Section translation fault, or attempt to use the encoding
@@ -6489,7 +6509,8 @@ static bool get_phys_addr_v6(CPUARMState *env, uint32_t 
address,
         /* Lookup l2 entry.  */
         table = (desc & 0xfffffc00) | ((address >> 10) & 0x3fc);
         desc = arm_ldl_ptw(cs, table, regime_is_secure(env, mmu_idx),
-                           mmu_idx, fsr, fi);
+                           mmu_idx, fsr, fi,
+                           regime_translation_big_endian(env, mmu_idx));
         ap = ((desc >> 4) & 3) | ((desc >> 7) & 4);
         switch (desc & 3) {
         case 0: /* Page translation fault.  */
@@ -6862,7 +6883,8 @@ static bool get_phys_addr_lpae(CPUARMState *env, 
target_ulong address,
         descaddr |= (address >> (stride * (4 - level))) & descmask;
         descaddr &= ~7ULL;
         nstable = extract32(tableattrs, 4, 1);
-        descriptor = arm_ldq_ptw(cs, descaddr, !nstable, mmu_idx, fsr, fi);
+        descriptor = arm_ldq_ptw(cs, descaddr, !nstable, mmu_idx, fsr, fi,
+                                 regime_translation_big_endian(env, mmu_idx));
         if (fi->s1ptw) {
             goto do_fault;
         }
-- 
1.9.1