[Qemu-devel] [PULL 22/28] arm: Implement uniprocessor with MP config

[Peter Maydell]

From: Peter Crosthwaite <address@hidden>

Add a boolean for indicating uniprocessors with MP extensions. This
drives the U bit in MPIDR. Prepares support for Cortex-R5.

Signed-off-by: Peter Crosthwaite <address@hidden>
Message-id: address@hidden
Reviewed-by: Peter Maydell <address@hidden>
Signed-off-by: Peter Maydell <address@hidden>
---
 target-arm/cpu-qom.h | 3 +++
 target-arm/helper.c  | 6 ++++--
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/target-arm/cpu-qom.h b/target-arm/cpu-qom.h
index 24a4cfb..57b4a12 100644
--- a/target-arm/cpu-qom.h
+++ b/target-arm/cpu-qom.h
@@ -116,6 +116,9 @@ typedef struct ARMCPU {
     /* KVM init features for this CPU */
     uint32_t kvm_init_features[7];
 
+    /* Uniprocessor system with MP extensions */
+    bool mp_is_up;
+
     /* The instance init functions for implementation-specific subclasses
      * set these fields to specify the implementation-dependent values of
      * various constant registers and reset values of non-constant
diff --git a/target-arm/helper.c b/target-arm/helper.c
index f51dece..f038a03a 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -2075,9 +2075,11 @@ static uint64_t mpidr_read(CPUARMState *env, const 
ARMCPRegInfo *ri)
         mpidr |= (1U << 31);
         /* Cores which are uniprocessor (non-coherent)
          * but still implement the MP extensions set
-         * bit 30. (For instance, A9UP.) However we do
-         * not currently model any of those cores.
+         * bit 30. (For instance, Cortex-R5).
          */
+        if (cpu->mp_is_up) {
+            mpidr |= (1u << 30);
+        }
     }
     return mpidr;
 }
-- 
1.9.1