[PATCH v3 05/10] arm/cpu: accessors for writable id registers

[Cornelia Huck <cohuck@redhat.com>]

Also add conversion between the different indices.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
---
 target/arm/cpu.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index bbee7ff2414a..775a8aebc5d3 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -876,6 +876,13 @@ typedef struct IdRegMap {
     uint64_t regs[NR_ID_REGS];
 } IdRegMap;
 
+#define ARM_FEATURE_ID_RANGE_IDX(op0, op1, crn, crm, op2)               \
+        ({                                                              \
+                __u64 __op1 = (op1) & 3;                                \
+                __op1 -= (__op1 == 3);                                  \
+                (__op1 << 6 | ((crm) & 7) << 3 | (op2));                \
+        })
+
 /* REG is ID_XXX */
 #define FIELD_DP64_IDREG(ISAR, REG, FIELD, VALUE)                       \
     ({                                                                  \
@@ -923,6 +930,17 @@ typedef struct IdRegMap {
         i_->idregs[REG ## _EL1_IDX];                                    \
     })
 
+#define GET_IDREG_WRITABLE(MAP, REG)                                  \
+    ({                                                                \
+    const IdRegMap *m_ = (MAP);                                       \
+    int index = ARM_FEATURE_ID_RANGE_IDX((sysreg >> 14) & 0x0000c000, \
+                                         (sysreg >> 11) & 0x00003800, \
+                                         (sysreg >> 7) & 0x00000780,  \
+                                         (sysreg >> 3) & 0x00000078,  \
+                                         sysreg & 0x00000007);        \
+    m_->regs[index];                                                  \
+    })
+
 /**
  * ARMCPU:
  * @env: #CPUARMState
-- 
2.49.0