xref: /openbmc/qemu/include/hw/misc/auxbus.h (revision 416296a9)
1 /*
2  * auxbus.h
3  *
4  *  Copyright (C)2014 : GreenSocs Ltd
5  *      http://www.greensocs.com/ , email: info@greensocs.com
6  *
7  *  Developed by :
8  *  Frederic Konrad   <fred.konrad@greensocs.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation, either version 2 of the License, or
13  * (at your option)any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License along
21  * with this program; if not, see <http://www.gnu.org/licenses/>.
22  *
23  */
24 
25 #ifndef HW_MISC_AUXBUS_H
26 #define HW_MISC_AUXBUS_H
27 
28 #include "hw/qdev.h"
29 
30 typedef struct AUXBus AUXBus;
31 typedef struct AUXSlave AUXSlave;
32 typedef enum AUXCommand AUXCommand;
33 typedef enum AUXReply AUXReply;
34 typedef struct AUXTOI2CState AUXTOI2CState;
35 
36 enum AUXCommand {
37     WRITE_I2C = 0,
38     READ_I2C = 1,
39     WRITE_I2C_STATUS = 2,
40     WRITE_I2C_MOT = 4,
41     READ_I2C_MOT = 5,
42     WRITE_AUX = 8,
43     READ_AUX = 9
44 };
45 
46 enum AUXReply {
47     AUX_I2C_ACK = 0,
48     AUX_NACK = 1,
49     AUX_DEFER = 2,
50     AUX_I2C_NACK = 4,
51     AUX_I2C_DEFER = 8
52 };
53 
54 #define TYPE_AUX_BUS "aux-bus"
55 #define AUX_BUS(obj) OBJECT_CHECK(AUXBus, (obj), TYPE_AUX_BUS)
56 
57 struct AUXBus {
58     /* < private > */
59     BusState qbus;
60 
61     /* < public > */
62     AUXSlave *current_dev;
63     AUXSlave *dev;
64     uint32_t last_i2c_address;
65     AUXCommand last_transaction;
66 
67     AUXTOI2CState *bridge;
68 
69     MemoryRegion *aux_io;
70     AddressSpace aux_addr_space;
71 };
72 
73 #define TYPE_AUX_SLAVE "aux-slave"
74 #define AUX_SLAVE(obj) \
75      OBJECT_CHECK(AUXSlave, (obj), TYPE_AUX_SLAVE)
76 
77 struct AUXSlave {
78     /* < private > */
79     DeviceState parent_obj;
80 
81     /* < public > */
82     MemoryRegion *mmio;
83 };
84 
85 /**
86  * aux_init_bus: Initialize an AUX bus.
87  *
88  * Returns the new AUX bus created.
89  *
90  * @parent The device where this bus is located.
91  * @name The name of the bus.
92  */
93 AUXBus *aux_init_bus(DeviceState *parent, const char *name);
94 
95 /*
96  * aux_request: Make a request on the bus.
97  *
98  * Returns the reply of the request.
99  *
100  * @bus Ths bus where the request happen.
101  * @cmd The command requested.
102  * @address The 20bits address of the slave.
103  * @len The length of the read or write.
104  * @data The data array which will be filled or read during transfer.
105  */
106 AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
107                               uint8_t len, uint8_t *data);
108 
109 /*
110  * aux_get_i2c_bus: Get the i2c bus for I2C over AUX command.
111  *
112  * Returns the i2c bus associated to this AUX bus.
113  *
114  * @bus The AUX bus.
115  */
116 I2CBus *aux_get_i2c_bus(AUXBus *bus);
117 
118 /*
119  * aux_init_mmio: Init an mmio for an AUX slave.
120  *
121  * @aux_slave The AUX slave.
122  * @mmio The mmio to be registered.
123  */
124 void aux_init_mmio(AUXSlave *aux_slave, MemoryRegion *mmio);
125 
126 DeviceState *aux_create_slave(AUXBus *bus, const char *name, uint32_t addr);
127 
128 #endif /* HW_MISC_AUXBUS_H */
129