diff options
Diffstat (limited to 'hw/ssi/ssi.c')
| -rw-r--r-- | hw/ssi/ssi.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/hw/ssi/ssi.c b/hw/ssi/ssi.c new file mode 100644 index 0000000000..1264d9da23 --- /dev/null +++ b/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 qbus; +}; + +#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(&s->qdev, ssi_cs_default, 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->qbus, 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 FROM_QBUS(SSIBus, bus); +} + +uint32_t ssi_transfer(SSIBus *bus, uint32_t val) +{ + BusChild *kid; + SSISlaveClass *ssc; + uint32_t r = 0; + + QTAILQ_FOREACH(kid, &bus->qbus.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, + .minimum_version_id_old = 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(DEVICE(dev), 0); + qdev_set_parent_bus(DEVICE(dev), &arg->bus->qbus); + **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); +} |