[Qemu-devel] [PATCH 17/24] target-arm: Implement AArch64 TCR_EL1

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

Implement the AArch64 TCR_EL1, which is the 64 bit view of
the AArch32 TTBCR. (The uses of the bits in the register are
completely different, but in any given situation the CPU will
always interpret them one way or the other. In fact for QEMU EL1
is always 64 bit, but we share the state field because this
is the correct mapping to permit a future implementation of EL2.)
We also make the AArch64 view the 'master' as far as migration
and reset is concerned.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target-arm/cpu.h    |  2 +-
 target-arm/helper.c | 20 +++++++++++++++++---
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/target-arm/cpu.h b/target-arm/cpu.h
index 16f1d27..a7d6274 100644
--- a/target-arm/cpu.h
+++ b/target-arm/cpu.h
@@ -177,7 +177,7 @@ typedef struct CPUARMState {
         uint32_t c2_base0_hi; /* MMU translation table base 0, high 32 bits */
         uint32_t c2_base1; /* MMU translation table base 0.  */
         uint32_t c2_base1_hi; /* MMU translation table base 1, high 32 bits */
-        uint32_t c2_control; /* MMU translation table base control.  */
+        uint64_t c2_control; /* MMU translation table base control.  */
         uint32_t c2_mask; /* MMU translation table base selection mask.  */
         uint32_t c2_base_mask; /* MMU translation table base 0 mask. */
         uint32_t c2_data; /* MPU data cachable bits.  */
diff --git a/target-arm/helper.c b/target-arm/helper.c
index f8f034c..5912b13 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -1272,6 +1272,15 @@ static void vmsa_ttbcr_reset(CPUARMState *env, const ARMCPRegInfo *ri)
     env->cp15.c2_mask = 0;
 }
 
+static int vmsa_tcr_el1_write(CPUARMState *env, const ARMCPRegInfo *ri,
+                              uint64_t value)
+{
+    /* For AArch64 the A1 bit could result in a change of ASID, so TLB flush. */
+    tlb_flush(env, 1);
+    env->cp15.c2_control = value;
+    return 0;
+}
+
 static const ARMCPRegInfo vmsa_cp_reginfo[] = {
     { .name = "DFSR", .cp = 15, .crn = 5, .crm = 0, .opc1 = 0, .opc2 = 0,
       .access = PL1_RW,
@@ -1285,10 +1294,15 @@ static const ARMCPRegInfo vmsa_cp_reginfo[] = {
     { .name = "TTBR1", .cp = 15, .crn = 2, .crm = 0, .opc1 = 0, .opc2 = 1,
       .access = PL1_RW,
       .fieldoffset = offsetof(CPUARMState, cp15.c2_base1), .resetvalue = 0, },
-    { .name = "TTBCR", .cp = 15, .crn = 2, .crm = 0, .opc1 = 0, .opc2 = 2,
-      .access = PL1_RW, .writefn = vmsa_ttbcr_write,
-      .resetfn = vmsa_ttbcr_reset, .raw_writefn = vmsa_ttbcr_raw_write,
+    { .name = "TCR_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .crn = 2, .crm = 0, .opc1 = 0, .opc2 = 2,
+      .access = PL1_RW, .writefn = vmsa_tcr_el1_write,
+      .resetfn = vmsa_ttbcr_reset, .raw_writefn = raw_write,
       .fieldoffset = offsetof(CPUARMState, cp15.c2_control) },
+    { .name = "TTBCR", .cp = 15, .crn = 2, .crm = 0, .opc1 = 0, .opc2 = 2,
+      .access = PL1_RW, .type = ARM_CP_NO_MIGRATE, .writefn = vmsa_ttbcr_write,
+      .resetfn = arm_cp_reset_ignore, .raw_writefn = vmsa_ttbcr_raw_write,
+      .fieldoffset = offsetoflow32(CPUARMState, cp15.c2_control) },
     { .name = "DFAR", .cp = 15, .crn = 6, .crm = 0, .opc1 = 0, .opc2 = 0,
       .access = PL1_RW, .fieldoffset = offsetof(CPUARMState, cp15.c6_data),
       .resetvalue = 0, },
-- 
1.8.5