hw/misc/tz-mpc.c: Implement the Arm TrustZone Memory Protection Controller

Implement the Arm TrustZone Memory Protection Controller, which sits
in front of RAM and allows secure software to configure it to either
pass through or reject transactions.

We implement the MPC as a QEMU IOMMU, which will direct transactions
either through to the devices and memory behind it or to a special
"never works" AddressSpace if they are blocked.

This initial commit implements the skeleton of the device:
 * it always permits accesses
 * it doesn't implement most of the registers
 * it doesn't implement the interrupt or other behaviour
   for blocked transactions

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20180620132032.28865-2-peter.maydell@linaro.org

1 files changed, 70 insertions, 0 deletions

diff --git a/include/hw/misc/tz-mpc.h b/include/hw/misc/tz-mpc.h
new file mode 100644
index 0000000000..d1a65fd9a3
--- /dev/null
+++ b/include/hw/misc/tz-mpc.h
@@ -0,0 +1,70 @@
+/*
+ * ARM AHB5 TrustZone Memory Protection Controller emulation
+ *
+ * Copyright (c) 2018 Linaro Limited
+ * Written by Peter Maydell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 or
+ * (at your option) any later version.
+ */
+
+/* This is a model of the TrustZone memory protection controller (MPC).
+ * It is documented in the ARM CoreLink SIE-200 System IP for Embedded TRM
+ * (DDI 0571G):
+ * https://developer.arm.com/products/architecture/m-profile/docs/ddi0571/g
+ *
+ * The MPC sits in front of memory and allows secure software to
+ * configure it to either pass through or reject transactions.
+ * Rejected transactions may be configured to either be aborted, or to
+ * behave as RAZ/WI. An interrupt can be signalled for a rejected transaction.
+ *
+ * The MPC has a register interface which the guest uses to configure it.
+ *
+ * QEMU interface:
+ * + sysbus MMIO region 0: MemoryRegion for the MPC's config registers
+ * + sysbus MMIO region 1: MemoryRegion for the upstream end of the MPC
+ * + Property "downstream": MemoryRegion defining the downstream memory
+ * + Named GPIO output "irq": set for a transaction-failed interrupt
+ */
+
+#ifndef TZ_MPC_H
+#define TZ_MPC_H
+
+#include "hw/sysbus.h"
+
+#define TYPE_TZ_MPC "tz-mpc"
+#define TZ_MPC(obj) OBJECT_CHECK(TZMPC, (obj), TYPE_TZ_MPC)
+
+#define TZ_NUM_PORTS 16
+
+#define TYPE_TZ_MPC_IOMMU_MEMORY_REGION "tz-mpc-iommu-memory-region"
+
+typedef struct TZMPC TZMPC;
+
+struct TZMPC {
+    /*< private >*/
+    SysBusDevice parent_obj;
+
+    /*< public >*/
+
+    qemu_irq irq;
+
+    /* Properties */
+    MemoryRegion *downstream;
+
+    hwaddr blocksize;
+    uint32_t blk_max;
+
+    /* MemoryRegions exposed to user */
+    MemoryRegion regmr;
+    IOMMUMemoryRegion upstream;
+
+    /* MemoryRegion used internally */
+    MemoryRegion blocked_io;
+
+    AddressSpace downstream_as;
+    AddressSpace blocked_io_as;
+};
+
+#endif