1 files changed, 174 insertions, 0 deletions

diff --git a/src/hw/ssi/ssi.c b/src/hw/ssi/ssi.c
new file mode 100644
index 0000000..2aab79b
--- /dev/null
+++ b/src/hw/ssi/ssi.c
@@ -0,0 +1,174 @@
+/*
+ * QEMU Synchronous Serial Interface support
+ *
+ * Copyright (c) 2009 CodeSourcery.
+ * Copyright (c) 2012 Peter A.G. Crosthwaite (peter.crosthwaite@petalogix.com)
+ * Copyright (c) 2012 PetaLogix Pty Ltd.
+ * Written by Paul Brook
+ *
+ * This code is licensed under the GNU GPL v2.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include "hw/ssi.h"
+
+struct SSIBus {
+    BusState parent_obj;
+};
+
+#define TYPE_SSI_BUS "SSI"
+#define SSI_BUS(obj) OBJECT_CHECK(SSIBus, (obj), TYPE_SSI_BUS)
+
+static const TypeInfo ssi_bus_info = {
+    .name = TYPE_SSI_BUS,
+    .parent = TYPE_BUS,
+    .instance_size = sizeof(SSIBus),
+};
+
+static void ssi_cs_default(void *opaque, int n, int level)
+{
+    SSISlave *s = SSI_SLAVE(opaque);
+    bool cs = !!level;
+    assert(n == 0);
+    if (s->cs != cs) {
+        SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s);
+        if (ssc->set_cs) {
+            ssc->set_cs(s, cs);
+        }
+    }
+    s->cs = cs;
+}
+
+static uint32_t ssi_transfer_raw_default(SSISlave *dev, uint32_t val)
+{
+    SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(dev);
+
+    if ((dev->cs && ssc->cs_polarity == SSI_CS_HIGH) ||
+            (!dev->cs && ssc->cs_polarity == SSI_CS_LOW) ||
+            ssc->cs_polarity == SSI_CS_NONE) {
+        return ssc->transfer(dev, val);
+    }
+    return 0;
+}
+
+static int ssi_slave_init(DeviceState *dev)
+{
+    SSISlave *s = SSI_SLAVE(dev);
+    SSISlaveClass *ssc = SSI_SLAVE_GET_CLASS(s);
+
+    if (ssc->transfer_raw == ssi_transfer_raw_default &&
+            ssc->cs_polarity != SSI_CS_NONE) {
+        qdev_init_gpio_in_named(dev, ssi_cs_default, SSI_GPIO_CS, 1);
+    }
+
+    return ssc->init(s);
+}
+
+static void ssi_slave_class_init(ObjectClass *klass, void *data)
+{
+    SSISlaveClass *ssc = SSI_SLAVE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->init = ssi_slave_init;
+    dc->bus_type = TYPE_SSI_BUS;
+    if (!ssc->transfer_raw) {
+        ssc->transfer_raw = ssi_transfer_raw_default;
+    }
+}
+
+static const TypeInfo ssi_slave_info = {
+    .name = TYPE_SSI_SLAVE,
+    .parent = TYPE_DEVICE,
+    .class_init = ssi_slave_class_init,
+    .class_size = sizeof(SSISlaveClass),
+    .abstract = true,
+};
+
+DeviceState *ssi_create_slave_no_init(SSIBus *bus, const char *name)
+{
+    return qdev_create(BUS(bus), name);
+}
+
+DeviceState *ssi_create_slave(SSIBus *bus, const char *name)
+{
+    DeviceState *dev = ssi_create_slave_no_init(bus, name);
+
+    qdev_init_nofail(dev);
+    return dev;
+}
+
+SSIBus *ssi_create_bus(DeviceState *parent, const char *name)
+{
+    BusState *bus;
+    bus = qbus_create(TYPE_SSI_BUS, parent, name);
+    return SSI_BUS(bus);
+}
+
+uint32_t ssi_transfer(SSIBus *bus, uint32_t val)
+{
+    BusState *b = BUS(bus);
+    BusChild *kid;
+    SSISlaveClass *ssc;
+    uint32_t r = 0;
+
+    QTAILQ_FOREACH(kid, &b->children, sibling) {
+        SSISlave *slave = SSI_SLAVE(kid->child);
+        ssc = SSI_SLAVE_GET_CLASS(slave);
+        r |= ssc->transfer_raw(slave, val);
+    }
+
+    return r;
+}
+
+const VMStateDescription vmstate_ssi_slave = {
+    .name = "SSISlave",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_BOOL(cs, SSISlave),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void ssi_slave_register_types(void)
+{
+    type_register_static(&ssi_bus_info);
+    type_register_static(&ssi_slave_info);
+}
+
+type_init(ssi_slave_register_types)
+
+typedef struct SSIAutoConnectArg {
+    qemu_irq **cs_linep;
+    SSIBus *bus;
+} SSIAutoConnectArg;
+
+static int ssi_auto_connect_slave(Object *child, void *opaque)
+{
+    SSIAutoConnectArg *arg = opaque;
+    SSISlave *dev = (SSISlave *)object_dynamic_cast(child, TYPE_SSI_SLAVE);
+    qemu_irq cs_line;
+
+    if (!dev) {
+        return 0;
+    }
+
+    cs_line = qdev_get_gpio_in_named(DEVICE(dev), SSI_GPIO_CS, 0);
+    qdev_set_parent_bus(DEVICE(dev), BUS(arg->bus));
+    **arg->cs_linep = cs_line;
+    (*arg->cs_linep)++;
+    return 0;
+}
+
+void ssi_auto_connect_slaves(DeviceState *parent, qemu_irq *cs_line,
+                             SSIBus *bus)
+{
+    SSIAutoConnectArg arg = {
+        .cs_linep = &cs_line,
+        .bus = bus
+    };
+
+    object_child_foreach(OBJECT(parent), ssi_auto_connect_slave, &arg);
+}