[Qemu-devel] [PATCH v2 03/35] target-arm: Define names for SCTLR bits

[Peter Maydell <peter.maydell@linaro.org>]

The SCTLR is full of bits for enabling or disabling various things, and so
there are many places in the code which check if certain bits are set.
Define some named constants for the SCTLR bits so these checks are easier
to read.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target-arm/cpu.c    |  2 +-
 target-arm/cpu.h    | 52 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 target-arm/helper.c | 16 ++++++++--------
 3 files changed, 61 insertions(+), 9 deletions(-)

diff --git a/target-arm/cpu.c b/target-arm/cpu.c
index 935269c..3014e86 100644
--- a/target-arm/cpu.c
+++ b/target-arm/cpu.c
@@ -128,7 +128,7 @@ static void arm_cpu_reset(CPUState *s)
         }
     }
 
-    if (env->cp15.c1_sys & (1 << 13)) {
+    if (env->cp15.c1_sys & SCTLR_V) {
             env->regs[15] = 0xFFFF0000;
     }
 
diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index 7ccdbae..4bad6c0 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -337,6 +337,58 @@ int cpu_arm_handle_mmu_fault (CPUARMState *env, target_ulong address, int rw,
                               int mmu_idx);
 #define cpu_handle_mmu_fault cpu_arm_handle_mmu_fault
 
+/* SCTLR bit meanings. Several bits have been reused in newer
+ * versions of the architecture; in that case we define constants
+ * for both old and new bit meanings. Code which tests against those
+ * bits should probably check or otherwise arrange that the CPU
+ * is the architectural version it expects.
+ */
+#define SCTLR_M       (1U << 0)
+#define SCTLR_A       (1U << 1)
+#define SCTLR_C       (1U << 2)
+#define SCTLR_W       (1U << 3) /* up to v6; RAO in v7 */
+#define SCTLR_SA      (1U << 3)
+#define SCTLR_P       (1U << 4) /* up to v5; RAO in v6 and v7 */
+#define SCTLR_SA0     (1U << 4) /* v8 onward, AArch64 only */
+#define SCTLR_D       (1U << 5) /* up to v5; RAO in v6 */
+#define SCTLR_CP15BEN (1U << 5) /* v7 onward */
+#define SCTLR_L       (1U << 6) /* up to v5; RAO in v6 and v7; RAZ in v8 */
+#define SCTLR_B       (1U << 7) /* up to v6; RAZ in v7 */
+#define SCTLR_ITD     (1U << 7) /* v8 onward */
+#define SCTLR_S       (1U << 8) /* up to v6; RAZ in v7 */
+#define SCTLR_SED     (1U << 8) /* v8 onward */
+#define SCTLR_R       (1U << 9) /* up to v6; RAZ in v7 */
+#define SCTLR_UMA     (1U << 9) /* v8 onward, AArch64 only */
+#define SCTLR_F       (1U << 10) /* up to v6 */
+#define SCTLR_SW      (1U << 10) /* v7 onward */
+#define SCTLR_Z       (1U << 11)
+#define SCTLR_I       (1U << 12)
+#define SCTLR_V       (1U << 13)
+#define SCTLR_RR      (1U << 14) /* up to v7 */
+#define SCTLR_DZE     (1U << 14) /* v8 onward, AArch64 only */
+#define SCTLR_L4      (1U << 15) /* up to v6; RAZ in v7 */
+#define SCTLR_UCT     (1U << 15) /* v8 onward, AArch64 only */
+#define SCTLR_DT      (1U << 16) /* up to ??, RAO in v6 and v7 */
+#define SCTLR_nTWI    (1U << 16) /* v8 onward */
+#define SCTLR_HA      (1U << 17)
+#define SCTLR_IT      (1U << 18) /* up to ??, RAO in v6 and v7 */
+#define SCTLR_nTWE    (1U << 18) /* v8 onward */
+#define SCTLR_WXN     (1U << 19)
+#define SCTLR_ST      (1U << 20) /* up to ??, RAZ in v6 */
+#define SCTLR_UWXN    (1U << 20) /* v7 onward */
+#define SCTLR_FI      (1U << 21)
+#define SCTLR_U       (1U << 22)
+#define SCTLR_XP      (1U << 23) /* up to v6; v7 onward RAO */
+#define SCTLR_VE      (1U << 24) /* up to v7 */
+#define SCTLR_E0E     (1U << 24) /* v8 onward, AArch64 only */
+#define SCTLR_EE      (1U << 25)
+#define SCTLR_L2      (1U << 26) /* up to v6, RAZ in v7 */
+#define SCTLR_UCI     (1U << 26) /* v8 onward, AArch64 only */
+#define SCTLR_NMFI    (1U << 27)
+#define SCTLR_TRE     (1U << 28)
+#define SCTLR_AFE     (1U << 29)
+#define SCTLR_TE      (1U << 30)
+
 #define CPSR_M (0x1fU)
 #define CPSR_T (1U << 5)
 #define CPSR_F (1U << 6)
diff --git a/target-arm/helper.c b/target-arm/helper.c
index e2cccb1..d670db8 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -2716,7 +2716,7 @@ void arm_cpu_do_interrupt(CPUState *cs)
         return; /* Never happens.  Keep compiler happy.  */
     }
     /* High vectors.  */
-    if (env->cp15.c1_sys & (1 << 13)) {
+    if (env->cp15.c1_sys & SCTLR_V) {
         /* when enabled, base address cannot be remapped.  */
         addr += 0xffff0000;
     } else {
@@ -2739,7 +2739,7 @@ void arm_cpu_do_interrupt(CPUState *cs)
     /* 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 */
     if (arm_feature(env, ARM_FEATURE_V4T)) {
-        env->thumb = (env->cp15.c1_sys & (1 << 30)) != 0;
+        env->thumb = (env->cp15.c1_sys & SCTLR_TE) != 0;
     }
     env->regs[14] = env->regs[15] + offset;
     env->regs[15] = addr;
@@ -2767,10 +2767,10 @@ static inline int check_ap(CPUARMState *env, int ap, int domain_prot,
   case 0:
       if (access_type == 1)
           return 0;
-      switch ((env->cp15.c1_sys >> 8) & 3) {
-      case 1:
+      switch (env->cp15.c1_sys & (SCTLR_S | SCTLR_R)) {
+      case SCTLR_S:
           return is_user ? 0 : PAGE_READ;
-      case 2:
+      case SCTLR_R:
           return PAGE_READ;
       default:
           return 0;
@@ -2999,7 +2999,7 @@ static int get_phys_addr_v6(CPUARMState *env, uint32_t address, int access_type,
             goto do_fault;
 
         /* The simplified model uses AP[0] as an access control bit.  */
-        if ((env->cp15.c1_sys & (1 << 29)) && (ap & 1) == 0) {
+        if ((env->cp15.c1_sys & SCTLR_AFE) && (ap & 1) == 0) {
             /* Access flag fault.  */
             code = (code == 15) ? 6 : 3;
             goto do_fault;
@@ -3290,7 +3290,7 @@ static inline int get_phys_addr(CPUARMState *env, uint32_t address,
     if (address < 0x02000000)
         address += env->cp15.c13_fcse;
 
-    if ((env->cp15.c1_sys & 1) == 0) {
+    if ((env->cp15.c1_sys & SCTLR_M) == 0) {
         /* MMU/MPU disabled.  */
         *phys_ptr = address;
         *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
@@ -3303,7 +3303,7 @@ static inline int get_phys_addr(CPUARMState *env, uint32_t address,
     } else if (extended_addresses_enabled(env)) {
         return get_phys_addr_lpae(env, address, access_type, is_user, phys_ptr,
                                   prot, page_size);
-    } else if (env->cp15.c1_sys & (1 << 23)) {
+    } else if (env->cp15.c1_sys & SCTLR_XP) {
         return get_phys_addr_v6(env, address, access_type, is_user, phys_ptr,
                                 prot, page_size);
     } else {
-- 
1.8.5