raspi: add BCM2835 SOC MPHI emulation

Add BCM2835 SOC MPHI (Message-based Parallel Host Interface)
emulation. It is very basic, only providing the FIQ interrupt
needed to allow the dwc-otg USB host controller driver in the
Raspbian kernel to function.

Signed-off-by: Paul Zimmerman <pauldzim@gmail.com>
Acked-by: Philippe Mathieu-Daude <f4bug@amsat.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200520235349.21215-2-pauldzim@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

include/hw/arm/bcm2835_peripherals.h

@@ -21,6 +21,7 @@
 #include "hw/misc/bcm2835_property.h"
 #include "hw/misc/bcm2835_rng.h"
 #include "hw/misc/bcm2835_mbox.h"
+#include "hw/misc/bcm2835_mphi.h"
 #include "hw/misc/bcm2835_thermal.h"
 #include "hw/sd/sdhci.h"
 #include "hw/sd/bcm2835_sdhost.h"
@@ -42,6 +43,7 @@ typedef struct BCM2835PeripheralState {
     qemu_irq irq, fiq;
 
     BCM2835SystemTimerState systmr;
+    BCM2835MphiState mphi;
     UnimplementedDeviceState armtmr;
     UnimplementedDeviceState cprman;
     UnimplementedDeviceState a2w;

include/hw/misc/bcm2835_mphi.h

@@ -0,0 +1,44 @@
+/*
+ * BCM2835 SOC MPHI state definitions
+ *
+ * Copyright (c) 2020 Paul Zimmerman <pauldzim@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef HW_MISC_BCM2835_MPHI_H
+#define HW_MISC_BCM2835_MPHI_H
+
+#include "hw/irq.h"
+#include "hw/sysbus.h"
+
+#define MPHI_MMIO_SIZE      0x1000
+
+typedef struct BCM2835MphiState BCM2835MphiState;
+
+struct BCM2835MphiState {
+    SysBusDevice parent_obj;
+    qemu_irq irq;
+    MemoryRegion iomem;
+
+    uint32_t outdda;
+    uint32_t outddb;
+    uint32_t ctrl;
+    uint32_t intstat;
+    uint32_t swirq;
+};
+
+#define TYPE_BCM2835_MPHI   "bcm2835-mphi"
+
+#define BCM2835_MPHI(obj) \
+    OBJECT_CHECK(BCM2835MphiState, (obj), TYPE_BCM2835_MPHI)
+
+#endif