xref: /openbmc/qemu/include/hw/misc/auxbus.h (revision 4921d0a7)
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 "exec/memory.h"
29 #include "hw/qdev-core.h"
30 #include "qom/object.h"
31 
32 typedef struct AUXSlave AUXSlave;
33 typedef enum AUXCommand AUXCommand;
34 typedef enum AUXReply AUXReply;
35 
36 #define TYPE_AUXTOI2C "aux-to-i2c-bridge"
37 OBJECT_DECLARE_SIMPLE_TYPE(AUXTOI2CState, AUXTOI2C)
38 
39 enum AUXCommand {
40     WRITE_I2C = 0,
41     READ_I2C = 1,
42     WRITE_I2C_STATUS = 2,
43     WRITE_I2C_MOT = 4,
44     READ_I2C_MOT = 5,
45     WRITE_AUX = 8,
46     READ_AUX = 9
47 };
48 
49 enum AUXReply {
50     AUX_I2C_ACK = 0,
51     AUX_NACK = 1,
52     AUX_DEFER = 2,
53     AUX_I2C_NACK = 4,
54     AUX_I2C_DEFER = 8
55 };
56 
57 #define TYPE_AUX_BUS "aux-bus"
58 OBJECT_DECLARE_SIMPLE_TYPE(AUXBus, AUX_BUS)
59 
60 struct AUXBus {
61     /* < private > */
62     BusState qbus;
63 
64     /* < public > */
65     AUXSlave *current_dev;
66     AUXSlave *dev;
67     uint32_t last_i2c_address;
68     AUXCommand last_transaction;
69 
70     AUXTOI2CState *bridge;
71 
72     MemoryRegion *aux_io;
73     AddressSpace aux_addr_space;
74 };
75 
76 #define TYPE_AUX_SLAVE "aux-slave"
77 OBJECT_DECLARE_SIMPLE_TYPE(AUXSlave, AUX_SLAVE)
78 
79 struct AUXSlave {
80     /* < private > */
81     DeviceState parent_obj;
82 
83     /* < public > */
84     MemoryRegion *mmio;
85 };
86 
87 /**
88  * aux_bus_init: Initialize an AUX bus.
89  *
90  * Returns the new AUX bus created.
91  *
92  * @parent The device where this bus is located.
93  * @name The name of the bus.
94  */
95 AUXBus *aux_bus_init(DeviceState *parent, const char *name);
96 
97 /**
98  * aux_bus_realize: Realize an AUX bus.
99  *
100  * @bus: The AUX bus.
101  */
102 void aux_bus_realize(AUXBus *bus);
103 
104 /*
105  * aux_request: Make a request on the bus.
106  *
107  * Returns the reply of the request.
108  *
109  * @bus The bus where the request happen.
110  * @cmd The command requested.
111  * @address The 20bits address of the slave.
112  * @len The length of the read or write.
113  * @data The data array which will be filled or read during transfer.
114  */
115 AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
116                               uint8_t len, uint8_t *data);
117 
118 /*
119  * aux_get_i2c_bus: Get the i2c bus for I2C over AUX command.
120  *
121  * Returns the i2c bus associated to this AUX bus.
122  *
123  * @bus The AUX bus.
124  */
125 I2CBus *aux_get_i2c_bus(AUXBus *bus);
126 
127 /*
128  * aux_init_mmio: Init an mmio for an AUX slave.
129  *
130  * @aux_slave The AUX slave.
131  * @mmio The mmio to be registered.
132  */
133 void aux_init_mmio(AUXSlave *aux_slave, MemoryRegion *mmio);
134 
135 /* aux_map_slave: Map the mmio for an AUX slave on the bus.
136  *
137  * @dev The AUX slave.
138  * @addr The address for the slave's mmio.
139  */
140 void aux_map_slave(AUXSlave *dev, hwaddr addr);
141 
142 #endif /* HW_MISC_AUXBUS_H */
143