1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (c) 2015-2018, Intel Corporation.
4  */
5 
6 #ifndef __KCS_BMC_H__
7 #define __KCS_BMC_H__
8 
9 #include <linux/miscdevice.h>
10 
11 /* Different phases of the KCS BMC module.
12  *  KCS_PHASE_IDLE:
13  *            BMC should not be expecting nor sending any data.
14  *  KCS_PHASE_WRITE_START:
15  *            BMC is receiving a WRITE_START command from system software.
16  *  KCS_PHASE_WRITE_DATA:
17  *            BMC is receiving a data byte from system software.
18  *  KCS_PHASE_WRITE_END_CMD:
19  *            BMC is waiting a last data byte from system software.
20  *  KCS_PHASE_WRITE_DONE:
21  *            BMC has received the whole request from system software.
22  *  KCS_PHASE_WAIT_READ:
23  *            BMC is waiting the response from the upper IPMI service.
24  *  KCS_PHASE_READ:
25  *            BMC is transferring the response to system software.
26  *  KCS_PHASE_ABORT_ERROR1:
27  *            BMC is waiting error status request from system software.
28  *  KCS_PHASE_ABORT_ERROR2:
29  *            BMC is waiting for idle status afer error from system software.
30  *  KCS_PHASE_ERROR:
31  *            BMC has detected a protocol violation at the interface level.
32  */
33 enum kcs_phases {
34 	KCS_PHASE_IDLE,
35 
36 	KCS_PHASE_WRITE_START,
37 	KCS_PHASE_WRITE_DATA,
38 	KCS_PHASE_WRITE_END_CMD,
39 	KCS_PHASE_WRITE_DONE,
40 
41 	KCS_PHASE_WAIT_READ,
42 	KCS_PHASE_READ,
43 
44 	KCS_PHASE_ABORT_ERROR1,
45 	KCS_PHASE_ABORT_ERROR2,
46 	KCS_PHASE_ERROR
47 };
48 
49 /* IPMI 2.0 - Table 9-4, KCS Interface Status Codes */
50 enum kcs_errors {
51 	KCS_NO_ERROR                = 0x00,
52 	KCS_ABORTED_BY_COMMAND      = 0x01,
53 	KCS_ILLEGAL_CONTROL_CODE    = 0x02,
54 	KCS_LENGTH_ERROR            = 0x06,
55 	KCS_UNSPECIFIED_ERROR       = 0xFF
56 };
57 
58 /* IPMI 2.0 - 9.5, KCS Interface Registers
59  * @idr: Input Data Register
60  * @odr: Output Data Register
61  * @str: Status Register
62  */
63 struct kcs_ioreg {
64 	u32 idr;
65 	u32 odr;
66 	u32 str;
67 };
68 
69 struct kcs_bmc {
70 	spinlock_t lock;
71 
72 	u32 channel;
73 	int running;
74 
75 	/* Setup by BMC KCS controller driver */
76 	struct kcs_ioreg ioreg;
77 	u8 (*io_inputb)(struct kcs_bmc *kcs_bmc, u32 reg);
78 	void (*io_outputb)(struct kcs_bmc *kcs_bmc, u32 reg, u8 b);
79 
80 	enum kcs_phases phase;
81 	enum kcs_errors error;
82 
83 	wait_queue_head_t queue;
84 	bool data_in_avail;
85 	int  data_in_idx;
86 	u8  *data_in;
87 
88 	int  data_out_idx;
89 	int  data_out_len;
90 	u8  *data_out;
91 
92 	struct mutex mutex;
93 	u8 *kbuffer;
94 
95 	struct miscdevice miscdev;
96 
97 	unsigned long priv[];
98 };
99 
kcs_bmc_priv(struct kcs_bmc * kcs_bmc)100 static inline void *kcs_bmc_priv(struct kcs_bmc *kcs_bmc)
101 {
102 	return kcs_bmc->priv;
103 }
104 
105 int kcs_bmc_handle_event(struct kcs_bmc *kcs_bmc);
106 struct kcs_bmc *kcs_bmc_alloc(struct device *dev, int sizeof_priv,
107 					u32 channel);
108 #endif /* __KCS_BMC_H__ */
109