arm: add MPU support to M profile CPUs

The M series MPU is almost the same as the already implemented R
profile MPU (v7 PMSA).  So all we need to implement here is the MPU
register interface in the system register space.

This implementation has the same restriction as the R profile MPU
that it doesn't permit regions to be sized down smaller than 1K.

We also do not yet implement support for MPU_CTRL.HFNMIENA; this
bit should if zero disable use of the MPU when running HardFault,
NMI or with FAULTMASK set to 1 (ie at an execution priority of
less than zero) -- if the MPU is enabled we don't treat these
cases any differently.

Signed-off-by: Michael Davidsaver <mdavidsaver@gmail.com>
Message-id: 1493122030-32191-13-git-send-email-peter.maydell@linaro.org
[PMM: Keep all the bits in mpu_ctrl field, rather than
 using SCTLR bits for them; drop broken HFNMIENA support;
 various cleanup]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/target/arm/machine.c b/target/arm/machine.c
index ac6b758e3b..1a40469015 100644
--- a/target/arm/machine.c
+++ b/target/arm/machine.c
@@ -99,8 +99,8 @@ static bool m_needed(void *opaque)
 
 static const VMStateDescription vmstate_m = {
     .name = "cpu/m",
-    .version_id = 3,
-    .minimum_version_id = 3,
+    .version_id = 4,
+    .minimum_version_id = 4,
     .needed = m_needed,
     .fields = (VMStateField[]) {
         VMSTATE_UINT32(env.v7m.vecbase, ARMCPU),
@@ -112,6 +112,7 @@ static const VMStateDescription vmstate_m = {
         VMSTATE_UINT32(env.v7m.dfsr, ARMCPU),
         VMSTATE_UINT32(env.v7m.mmfar, ARMCPU),
         VMSTATE_UINT32(env.v7m.bfar, ARMCPU),
+        VMSTATE_UINT32(env.v7m.mpu_ctrl, ARMCPU),
         VMSTATE_INT32(env.v7m.exception, ARMCPU),
         VMSTATE_END_OF_LIST()
     }