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SSP bus framework

Signed-off-by: Paul Brook <paul@codesourcery.com>
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1 parent 1de9610 commit 90d37239d4051281d2882117efc73020046c32ca Paul Brook committed May 14, 2009
Showing with 95 additions and 1 deletion.
  1. +1 −1 Makefile
  2. +52 −0 hw/ssi.c
  3. +41 −0 hw/ssi.h
  4. +1 −0 qemu-common.h
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2 Makefile
@@ -101,7 +101,7 @@ OBJS+=bt-hci-csr.o
OBJS+=buffered_file.o migration.o migration-tcp.o net.o qemu-sockets.o
OBJS+=qemu-char.o aio.o net-checksum.o savevm.o cache-utils.o
OBJS+=msmouse.o ps2.o
-OBJS+=qdev.o
+OBJS+=qdev.o ssi.o
ifdef CONFIG_BRLAPI
OBJS+= baum.o
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52 hw/ssi.c
@@ -0,0 +1,52 @@
+/*
+ * QEMU Synchronous Serial Interface support
+ *
+ * Copyright (c) 2009 CodeSourcery.
+ * Written by Paul Brook
+ *
+ * This code is licenced under the GNU GPL v2.
+ */
+
+#include "ssi.h"
+
+struct SSIBus {
+ SSISlave *slave;
+};
+
+static void ssi_slave_init(DeviceState *dev, void *opaque)
+{
+ SSISlaveInfo *info = opaque;
+ SSISlave *s = SSI_SLAVE_FROM_QDEV(dev);
+ SSIBus *bus = qdev_get_bus(dev);
+
+ bus->slave = s;
+ s->info = info;
+ info->init(s);
+}
+
+void ssi_register_slave(const char *name, int size, SSISlaveInfo *info)
+{
+ assert(size >= sizeof(SSISlave));
+ qdev_register(name, size, ssi_slave_init, info);
+}
+
+DeviceState *ssi_create_slave(SSIBus *bus, const char *name)
+{
+ DeviceState *dev;
+ dev = qdev_create(bus, name);
+ qdev_init(dev);
+ return dev;
+}
+
+SSIBus *ssi_create_bus(void)
+{
+ return qemu_mallocz(sizeof(SSIBus));
+}
+
+uint32_t ssi_transfer(SSIBus *bus, uint32_t val)
+{
+ if (!bus->slave) {
+ return 0;
+ }
+ return bus->slave->info->transfer(bus->slave, val);
+}
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41 hw/ssi.h
@@ -0,0 +1,41 @@
+/* QEMU Synchronous Serial Interface support. */
+
+/* In principle SSI is a point-point interface. As such the qemu
+ implementation has a single slave device on a "bus".
+ However it is fairly common for boards to have multiple slaves
+ connected to a single master, and select devices with an external
+ chip select. This is implemented in qemu by having an explicit mux device.
+ It is assumed that master and slave are both using the same transfer width.
+ */
+
+#ifndef QEMU_SSI_H
+#define QEMU_SSI_H
+
+#include "qdev.h"
+
+typedef struct SSISlave SSISlave;
+
+/* Slave devices. */
+typedef struct {
+ void (*init)(SSISlave *dev);
+ uint32_t (*transfer)(SSISlave *dev, uint32_t val);
+} SSISlaveInfo;
+
+struct SSISlave {
+ DeviceState qdev;
+ SSISlaveInfo *info;
+};
+
+#define SSI_SLAVE_FROM_QDEV(dev) DO_UPCAST(SSISlave, qdev, dev)
+#define FROM_SSI_SLAVE(type, dev) DO_UPCAST(type, ssidev, dev)
+
+void ssi_register_slave(const char *name, int size, SSISlaveInfo *info);
+
+DeviceState *ssi_create_slave(SSIBus *bus, const char *name);
+
+/* Master interface. */
+SSIBus *ssi_create_bus(void);
+
+uint32_t ssi_transfer(SSIBus *bus, uint32_t val);
+
+#endif
View
1 qemu-common.h
@@ -183,6 +183,7 @@ typedef struct MouseTransformInfo MouseTransformInfo;
typedef struct uWireSlave uWireSlave;
typedef struct I2SCodec I2SCodec;
typedef struct DeviceState DeviceState;
+typedef struct SSIBus SSIBus;
/* CPU save/load. */
void cpu_save(QEMUFile *f, void *opaque);

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