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-rw-r--r--hw/misc/auxbus.c292
1 files changed, 292 insertions, 0 deletions
diff --git a/hw/misc/auxbus.c b/hw/misc/auxbus.c
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+/*
+ * auxbus.c
+ *
+ * Copyright 2015 : GreenSocs Ltd
+ * http://www.greensocs.com/ , email: info@greensocs.com
+ *
+ * Developed by :
+ * Frederic Konrad <fred.konrad@greensocs.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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+/*
+ * This is an implementation of the AUX bus for VESA Display Port v1.1a.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/misc/auxbus.h"
+#include "hw/i2c/i2c.h"
+#include "monitor/monitor.h"
+
+#ifndef DEBUG_AUX
+#define DEBUG_AUX 0
+#endif
+
+#define DPRINTF(fmt, ...) do { \
+ if (DEBUG_AUX) { \
+ qemu_log("aux: " fmt , ## __VA_ARGS__); \
+ } \
+} while (0);
+
+#define TYPE_AUXTOI2C "aux-to-i2c-bridge"
+#define AUXTOI2C(obj) OBJECT_CHECK(AUXTOI2CState, (obj), TYPE_AUXTOI2C)
+
+static void aux_slave_dev_print(Monitor *mon, DeviceState *dev, int indent);
+static inline I2CBus *aux_bridge_get_i2c_bus(AUXTOI2CState *bridge);
+
+/* aux-bus implementation (internal not public) */
+static void aux_bus_class_init(ObjectClass *klass, void *data)
+{
+ BusClass *k = BUS_CLASS(klass);
+
+ /* AUXSlave has an MMIO so we need to change the way we print information
+ * in monitor.
+ */
+ k->print_dev = aux_slave_dev_print;
+}
+
+AUXBus *aux_init_bus(DeviceState *parent, const char *name)
+{
+ AUXBus *bus;
+
+ bus = AUX_BUS(qbus_create(TYPE_AUX_BUS, parent, name));
+ bus->bridge = AUXTOI2C(qdev_create(BUS(bus), TYPE_AUXTOI2C));
+
+ /* Memory related. */
+ bus->aux_io = g_malloc(sizeof(*bus->aux_io));
+ memory_region_init(bus->aux_io, OBJECT(bus), "aux-io", (1 << 20));
+ address_space_init(&bus->aux_addr_space, bus->aux_io, "aux-io");
+ return bus;
+}
+
+static void aux_bus_map_device(AUXBus *bus, AUXSlave *dev, hwaddr addr)
+{
+ memory_region_add_subregion(bus->aux_io, addr, dev->mmio);
+}
+
+static bool aux_bus_is_bridge(AUXBus *bus, DeviceState *dev)
+{
+ return (dev == DEVICE(bus->bridge));
+}
+
+I2CBus *aux_get_i2c_bus(AUXBus *bus)
+{
+ return aux_bridge_get_i2c_bus(bus->bridge);
+}
+
+AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
+ uint8_t len, uint8_t *data)
+{
+ AUXReply ret = AUX_NACK;
+ I2CBus *i2c_bus = aux_get_i2c_bus(bus);
+ size_t i;
+ bool is_write = false;
+
+ DPRINTF("request at address 0x%" PRIX32 ", command %u, len %u\n", address,
+ cmd, len);
+
+ switch (cmd) {
+ /*
+ * Forward the request on the AUX bus..
+ */
+ case WRITE_AUX:
+ case READ_AUX:
+ is_write = cmd == READ_AUX ? false : true;
+ for (i = 0; i < len; i++) {
+ if (!address_space_rw(&bus->aux_addr_space, address++,
+ MEMTXATTRS_UNSPECIFIED, data++, 1,
+ is_write)) {
+ ret = AUX_I2C_ACK;
+ } else {
+ ret = AUX_NACK;
+ break;
+ }
+ }
+ break;
+ /*
+ * Classic I2C transactions..
+ */
+ case READ_I2C:
+ case WRITE_I2C:
+ is_write = cmd == READ_I2C ? false : true;
+ if (i2c_bus_busy(i2c_bus)) {
+ i2c_end_transfer(i2c_bus);
+ }
+
+ if (i2c_start_transfer(i2c_bus, address, is_write)) {
+ ret = AUX_I2C_NACK;
+ break;
+ }
+
+ ret = AUX_I2C_ACK;
+ while (len > 0) {
+ if (i2c_send_recv(i2c_bus, data++, is_write) < 0) {
+ ret = AUX_I2C_NACK;
+ break;
+ }
+ len--;
+ }
+ i2c_end_transfer(i2c_bus);
+ break;
+ /*
+ * I2C MOT transactions.
+ *
+ * Here we send a start when:
+ * - We didn't start transaction yet.
+ * - We had a READ and we do a WRITE.
+ * - We changed the address.
+ */
+ case WRITE_I2C_MOT:
+ case READ_I2C_MOT:
+ is_write = cmd == READ_I2C_MOT ? false : true;
+ ret = AUX_I2C_NACK;
+ if (!i2c_bus_busy(i2c_bus)) {
+ /*
+ * No transactions started..
+ */
+ if (i2c_start_transfer(i2c_bus, address, is_write)) {
+ break;
+ }
+ } else if ((address != bus->last_i2c_address) ||
+ (bus->last_transaction != cmd)) {
+ /*
+ * Transaction started but we need to restart..
+ */
+ i2c_end_transfer(i2c_bus);
+ if (i2c_start_transfer(i2c_bus, address, is_write)) {
+ break;
+ }
+ }
+
+ bus->last_transaction = cmd;
+ bus->last_i2c_address = address;
+ while (len > 0) {
+ if (i2c_send_recv(i2c_bus, data++, is_write) < 0) {
+ i2c_end_transfer(i2c_bus);
+ break;
+ }
+ len--;
+ }
+ if (len == 0) {
+ ret = AUX_I2C_ACK;
+ }
+ break;
+ default:
+ DPRINTF("Not implemented!\n");
+ return AUX_NACK;
+ }
+
+ DPRINTF("reply: %u\n", ret);
+ return ret;
+}
+
+static const TypeInfo aux_bus_info = {
+ .name = TYPE_AUX_BUS,
+ .parent = TYPE_BUS,
+ .instance_size = sizeof(AUXBus),
+ .class_init = aux_bus_class_init
+};
+
+/* aux-i2c implementation (internal not public) */
+struct AUXTOI2CState {
+ /*< private >*/
+ DeviceState parent_obj;
+
+ /*< public >*/
+ I2CBus *i2c_bus;
+};
+
+static void aux_bridge_init(Object *obj)
+{
+ AUXTOI2CState *s = AUXTOI2C(obj);
+
+ s->i2c_bus = i2c_init_bus(DEVICE(obj), "aux-i2c");
+}
+
+static inline I2CBus *aux_bridge_get_i2c_bus(AUXTOI2CState *bridge)
+{
+ return bridge->i2c_bus;
+}
+
+static const TypeInfo aux_to_i2c_type_info = {
+ .name = TYPE_AUXTOI2C,
+ .parent = TYPE_DEVICE,
+ .instance_size = sizeof(AUXTOI2CState),
+ .instance_init = aux_bridge_init
+};
+
+/* aux-slave implementation */
+static void aux_slave_dev_print(Monitor *mon, DeviceState *dev, int indent)
+{
+ AUXBus *bus = AUX_BUS(qdev_get_parent_bus(dev));
+ AUXSlave *s;
+
+ /* Don't print anything if the device is I2C "bridge". */
+ if (aux_bus_is_bridge(bus, dev)) {
+ return;
+ }
+
+ s = AUX_SLAVE(dev);
+
+ monitor_printf(mon, "%*smemory " TARGET_FMT_plx "/" TARGET_FMT_plx "\n",
+ indent, "",
+ object_property_get_int(OBJECT(s->mmio), "addr", NULL),
+ memory_region_size(s->mmio));
+}
+
+DeviceState *aux_create_slave(AUXBus *bus, const char *type, uint32_t addr)
+{
+ DeviceState *dev;
+
+ dev = DEVICE(object_new(type));
+ assert(dev);
+ qdev_set_parent_bus(dev, &bus->qbus);
+ qdev_init_nofail(dev);
+ aux_bus_map_device(AUX_BUS(qdev_get_parent_bus(dev)), AUX_SLAVE(dev), addr);
+ return dev;
+}
+
+void aux_init_mmio(AUXSlave *aux_slave, MemoryRegion *mmio)
+{
+ assert(!aux_slave->mmio);
+ aux_slave->mmio = mmio;
+}
+
+static void aux_slave_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *k = DEVICE_CLASS(klass);
+
+ set_bit(DEVICE_CATEGORY_MISC, k->categories);
+ k->bus_type = TYPE_AUX_BUS;
+}
+
+static const TypeInfo aux_slave_type_info = {
+ .name = TYPE_AUX_SLAVE,
+ .parent = TYPE_DEVICE,
+ .instance_size = sizeof(AUXSlave),
+ .abstract = true,
+ .class_init = aux_slave_class_init,
+};
+
+static void aux_register_types(void)
+{
+ type_register_static(&aux_bus_info);
+ type_register_static(&aux_slave_type_info);
+ type_register_static(&aux_to_i2c_type_info);
+}
+
+type_init(aux_register_types)
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-22 09:26:20 +0000