xref: /openbmc/qemu/include/hw/misc/auxbus.h (revision db1015e92e04835c9eb50c29625fe566d1202dbd)
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 AUXBus AUXBus;
33 typedef struct AUXSlave AUXSlave;
34 typedef enum AUXCommand AUXCommand;
35 typedef enum AUXReply AUXReply;
36 
37 #define TYPE_AUXTOI2C "aux-to-i2c-bridge"
38 typedef struct AUXTOI2CState AUXTOI2CState;
39 #define AUXTOI2C(obj) OBJECT_CHECK(AUXTOI2CState, (obj), TYPE_AUXTOI2C)
40 
41 enum AUXCommand {
42     WRITE_I2C = 0,
43     READ_I2C = 1,
44     WRITE_I2C_STATUS = 2,
45     WRITE_I2C_MOT = 4,
46     READ_I2C_MOT = 5,
47     WRITE_AUX = 8,
48     READ_AUX = 9
49 };
50 
51 enum AUXReply {
52     AUX_I2C_ACK = 0,
53     AUX_NACK = 1,
54     AUX_DEFER = 2,
55     AUX_I2C_NACK = 4,
56     AUX_I2C_DEFER = 8
57 };
58 
59 #define TYPE_AUX_BUS "aux-bus"
60 #define AUX_BUS(obj) OBJECT_CHECK(AUXBus, (obj), TYPE_AUX_BUS)
61 
62 struct AUXBus {
63     /* < private > */
64     BusState qbus;
65 
66     /* < public > */
67     AUXSlave *current_dev;
68     AUXSlave *dev;
69     uint32_t last_i2c_address;
70     AUXCommand last_transaction;
71 
72     AUXTOI2CState *bridge;
73 
74     MemoryRegion *aux_io;
75     AddressSpace aux_addr_space;
76 };
77 
78 #define TYPE_AUX_SLAVE "aux-slave"
79 #define AUX_SLAVE(obj) \
80      OBJECT_CHECK(AUXSlave, (obj), TYPE_AUX_SLAVE)
81 
82 struct AUXSlave {
83     /* < private > */
84     DeviceState parent_obj;
85 
86     /* < public > */
87     MemoryRegion *mmio;
88 };
89 
90 /**
91  * aux_bus_init: Initialize an AUX bus.
92  *
93  * Returns the new AUX bus created.
94  *
95  * @parent The device where this bus is located.
96  * @name The name of the bus.
97  */
98 AUXBus *aux_bus_init(DeviceState *parent, const char *name);
99 
100 /**
101  * aux_bus_realize: Realize an AUX bus.
102  *
103  * @bus: The AUX bus.
104  */
105 void aux_bus_realize(AUXBus *bus);
106 
107 /*
108  * aux_request: Make a request on the bus.
109  *
110  * Returns the reply of the request.
111  *
112  * @bus Ths bus where the request happen.
113  * @cmd The command requested.
114  * @address The 20bits address of the slave.
115  * @len The length of the read or write.
116  * @data The data array which will be filled or read during transfer.
117  */
118 AUXReply aux_request(AUXBus *bus, AUXCommand cmd, uint32_t address,
119                               uint8_t len, uint8_t *data);
120 
121 /*
122  * aux_get_i2c_bus: Get the i2c bus for I2C over AUX command.
123  *
124  * Returns the i2c bus associated to this AUX bus.
125  *
126  * @bus The AUX bus.
127  */
128 I2CBus *aux_get_i2c_bus(AUXBus *bus);
129 
130 /*
131  * aux_init_mmio: Init an mmio for an AUX slave.
132  *
133  * @aux_slave The AUX slave.
134  * @mmio The mmio to be registered.
135  */
136 void aux_init_mmio(AUXSlave *aux_slave, MemoryRegion *mmio);
137 
138 /* aux_map_slave: Map the mmio for an AUX slave on the bus.
139  *
140  * @dev The AUX slave.
141  * @addr The address for the slave's mmio.
142  */
143 void aux_map_slave(AUXSlave *dev, hwaddr addr);
144 
145 #endif /* HW_MISC_AUXBUS_H */
146