introduce aux-bus

This introduces a new bus: aux-bus.

It contains an address space for aux slaves devices and a bridge to an I2C bus
for I2C through AUX transactions.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Tested-By: Hyun Kwon <hyun.kwon@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@xilinx.com>
Message-id: 1465833014-21982-5-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 128 insertions, 0 deletions

diff --git a/include/hw/misc/aux.h b/include/hw/misc/aux.h
new file mode 100644
index 0000000..759c3bf
--- /dev/null
+++ b/include/hw/misc/aux.h
@@ -0,0 +1,128 @@
+/*
+ * aux.h
+ *
+ *  Copyright (C)2014 : 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/>.
+ *
+ */
+
+#ifndef QEMU_AUX_H
+#define QEMU_AUX_H
+
+#include "hw/qdev.h"
+
+typedef struct AUXBus AUXBus;
+typedef struct AUXSlave AUXSlave;
+typedef enum AUXCommand AUXCommand;
+typedef enum AUXReply AUXReply;
+typedef struct AUXTOI2CState AUXTOI2CState;
+
+enum AUXCommand {
+    WRITE_I2C = 0,
+    READ_I2C = 1,
+    WRITE_I2C_STATUS = 2,
+    WRITE_I2C_MOT = 4,
+    READ_I2C_MOT = 5,
+    WRITE_AUX = 8,
+    READ_AUX = 9
+};
+
+enum AUXReply {
+    AUX_I2C_ACK = 0,
+    AUX_NACK = 1,
+    AUX_DEFER = 2,
+    AUX_I2C_NACK = 4,
+    AUX_I2C_DEFER = 8
+};
+
+#define TYPE_AUX_BUS "aux-bus"
+#define AUX_BUS(obj) OBJECT_CHECK(AUXBus, (obj), TYPE_AUX_BUS)
+
+struct AUXBus {
+    /* < private > */
+    BusState qbus;
+
+    /* < public > */
+    AUXSlave *current_dev;
+    AUXSlave *dev;
+    uint32_t last_i2c_address;
+    AUXCommand last_transaction;
+
+    AUXTOI2CState *bridge;
+
+    MemoryRegion *aux_io;
+    AddressSpace aux_addr_space;
+};
+
+#define TYPE_AUX_SLAVE "aux-slave"
+#define AUX_SLAVE(obj) \
+     OBJECT_CHECK(AUXSlave, (obj), TYPE_AUX_SLAVE)
+
+struct AUXSlave {
+    /* < private > */
+    DeviceState parent_obj;
+
+    /* < public > */
+    MemoryRegion *mmio;
+};
+
+/**
+ * aux_init_bus: Initialize an AUX bus.
+ *
+ * Returns the new AUX bus created.
+ *
+ * @parent The device where this bus is located.
+ * @name The name of the bus.
+ */
+AUXBus *aux_init_bus(DeviceState *parent, const char *name);
+
+/*
+ * aux_request: Make a request on the bus.
+ *
+ * Returns the reply of the request.
+ *
+ * @bus Ths bus where the request happen.
+ * @cmd The command requested.
+ * @address The 20bits address of the slave.
+ * @len The length of the read or write.
+ * @data The data array which will be filled or read during transfer.
+ */
+AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
+                              uint8_t len, uint8_t *data);
+
+/*
+ * aux_get_i2c_bus: Get the i2c bus for I2C over AUX command.
+ *
+ * Returns the i2c bus associated to this AUX bus.
+ *
+ * @bus The AUX bus.
+ */
+I2CBus *aux_get_i2c_bus(AUXBus *bus);
+
+/*
+ * aux_init_mmio: Init an mmio for an AUX slave.
+ *
+ * @aux_slave The AUX slave.
+ * @mmio The mmio to be registered.
+ */
+void aux_init_mmio(AUXSlave *aux_slave, MemoryRegion *mmio);
+
+DeviceState *aux_create_slave(AUXBus *bus, const char *name, uint32_t addr);
+
+#endif /* !QEMU_AUX_H */