target-arm: Add the HSTR_EL2 register

Add the Hypervisor System Trap Register for EL2.

This register is used early in the Linux boot and without it the kernel
aborts with a "Synchronous Abort" error.

Signed-off-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: ea5aae4b10283de4705b864fe9d4bd2eaddaacae.1463174342.git.alistair.francis@xilinx.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/target-arm/helper.c b/target-arm/helper.c
index e3ea26f..9a6ff2e 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -3471,6 +3471,9 @@
       .opc0 = 3, .opc1 = 4, .crn = 6, .crm = 0, .opc2 = 4,
       .access = PL2_RW, .accessfn = access_el3_aa32ns_aa64any,
       .type = ARM_CP_CONST, .resetvalue = 0 },
+    { .name = "HSTR_EL2", .state = ARM_CP_STATE_BOTH,
+      .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 1, .opc2 = 3,
+      .access = PL2_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
     REGINFO_SENTINEL
 };
 
@@ -3706,6 +3709,10 @@
       .opc0 = 3, .opc1 = 4, .crn = 6, .crm = 0, .opc2 = 4,
       .access = PL2_RW,
       .fieldoffset = offsetof(CPUARMState, cp15.hpfar_el2) },
+    { .name = "HSTR_EL2", .state = ARM_CP_STATE_BOTH,
+      .cp = 15, .opc0 = 3, .opc1 = 4, .crn = 1, .crm = 1, .opc2 = 3,
+      .access = PL2_RW,
+      .fieldoffset = offsetof(CPUARMState, cp15.hstr_el2) },
     REGINFO_SENTINEL
 };