bcm2835_mbox: add BCM2835 mailboxes

This adds the system mailboxes which are used to communicate with a
number of GPU peripherals on Pi/Pi2.

Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

2 files changed, 65 insertions, 0 deletions

diff --git a/include/hw/misc/bcm2835_mbox.h b/include/hw/misc/bcm2835_mbox.h
new file mode 100644
index 0000000000..f4e9ff9ef6
--- /dev/null
+++ b/include/hw/misc/bcm2835_mbox.h
@@ -0,0 +1,38 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#ifndef BCM2835_MBOX_H
+#define BCM2835_MBOX_H
+
+#include "bcm2835_mbox_defs.h"
+#include "hw/sysbus.h"
+#include "exec/address-spaces.h"
+
+#define TYPE_BCM2835_MBOX "bcm2835-mbox"
+#define BCM2835_MBOX(obj) \
+        OBJECT_CHECK(BCM2835MboxState, (obj), TYPE_BCM2835_MBOX)
+
+typedef struct {
+    uint32_t reg[MBOX_SIZE];
+    uint32_t count;
+    uint32_t status;
+    uint32_t config;
+} BCM2835Mbox;
+
+typedef struct {
+    /*< private >*/
+    SysBusDevice busdev;
+    /*< public >*/
+    MemoryRegion *mbox_mr;
+    AddressSpace mbox_as;
+    MemoryRegion iomem;
+    qemu_irq arm_irq;
+
+    bool mbox_irq_disabled;
+    bool available[MBOX_CHAN_COUNT];
+    BCM2835Mbox mbox[2];
+} BCM2835MboxState;
+
+#endif
diff --git a/include/hw/misc/bcm2835_mbox_defs.h b/include/hw/misc/bcm2835_mbox_defs.h
new file mode 100644
index 0000000000..a18e520b22
--- /dev/null
+++ b/include/hw/misc/bcm2835_mbox_defs.h
@@ -0,0 +1,27 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#ifndef BCM2835_MBOX_DEFS_H
+#define BCM2835_MBOX_DEFS_H
+
+/* Constants shared with the ARM identifying separate mailbox channels */
+#define MBOX_CHAN_POWER    0 /* for use by the power management interface */
+#define MBOX_CHAN_FB       1 /* for use by the frame buffer */
+#define MBOX_CHAN_VCHIQ    3 /* for use by the VCHIQ interface */
+#define MBOX_CHAN_PROPERTY 8 /* for use by the property channel */
+#define MBOX_CHAN_COUNT    9
+
+#define MBOX_SIZE          32
+#define MBOX_INVALID_DATA  0x0f
+
+/* Layout of the private address space used for communication between
+ * the mbox device emulation, and child devices: each channel occupies
+ * 16 bytes of address space, but only two registers are presently defined.
+ */
+#define MBOX_AS_CHAN_SHIFT 4
+#define MBOX_AS_DATA       0 /* request / response data (RW at offset 0) */
+#define MBOX_AS_PENDING    4 /* pending response status (RO at offset 4) */
+
+#endif /* BCM2835_MBOX_DEFS_H */