1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * FSI master definitions. These comprise the core <--> master interface,
4 * to allow the core to interact with the (hardware-specific) masters.
5 *
6 * Copyright (C) IBM Corporation 2016
7 */
8
9#ifndef DRIVERS_FSI_MASTER_H
10#define DRIVERS_FSI_MASTER_H
11
12#include <linux/device.h>
13#include <linux/mutex.h>
14
15/*
16 * Master registers
17 *
18 * These are used by hardware masters, such as the one in the FSP2, AST2600 and
19 * the hub master in POWER processors.
20 */
21
22/* Control Registers */
23#define FSI_MMODE		0x0		/* R/W: mode */
24#define FSI_MDLYR		0x4		/* R/W: delay */
25#define FSI_MCRSP		0x8		/* R/W: clock rate */
26#define FSI_MENP0		0x10		/* R/W: enable */
27#define FSI_MLEVP0		0x18		/* R: plug detect */
28#define FSI_MSENP0		0x18		/* S: Set enable */
29#define FSI_MCENP0		0x20		/* C: Clear enable */
30#define FSI_MAEB		0x70		/* R: Error address */
31#define FSI_MVER		0x74		/* R: master version/type */
32#define FSI_MSTAP0		0xd0		/* R: Port status */
33#define FSI_MRESP0		0xd0		/* W: Port reset */
34#define FSI_MESRB0		0x1d0		/* R: Master error status */
35#define FSI_MRESB0		0x1d0		/* W: Reset bridge */
36#define FSI_MSCSB0		0x1d4		/* R: Master sub command stack */
37#define FSI_MATRB0		0x1d8		/* R: Master address trace */
38#define FSI_MDTRB0		0x1dc		/* R: Master data trace */
39#define FSI_MECTRL		0x2e0		/* W: Error control */
40
41/* MMODE: Mode control */
42#define FSI_MMODE_EIP		0x80000000	/* Enable interrupt polling */
43#define FSI_MMODE_ECRC		0x40000000	/* Enable error recovery */
44#define FSI_MMODE_RELA		0x20000000	/* Enable relative address commands */
45#define FSI_MMODE_EPC		0x10000000	/* Enable parity checking */
46#define FSI_MMODE_P8_TO_LSB	0x00000010	/* Timeout value LSB */
47						/*   MSB=1, LSB=0 is 0.8 ms */
48						/*   MSB=0, LSB=1 is 0.9 ms */
49#define FSI_MMODE_CRS0SHFT	18		/* Clk rate selection 0 shift */
50#define FSI_MMODE_CRS0MASK	0x3ff		/* Clk rate selection 0 mask */
51#define FSI_MMODE_CRS1SHFT	8		/* Clk rate selection 1 shift */
52#define FSI_MMODE_CRS1MASK	0x3ff		/* Clk rate selection 1 mask */
53
54/* MRESB: Reset bridge */
55#define FSI_MRESB_RST_GEN	0x80000000	/* General reset */
56#define FSI_MRESB_RST_ERR	0x40000000	/* Error Reset */
57
58/* MRESP: Reset port */
59#define FSI_MRESP_RST_ALL_MASTER 0x20000000	/* Reset all FSI masters */
60#define FSI_MRESP_RST_ALL_LINK	0x10000000	/* Reset all FSI port contr. */
61#define FSI_MRESP_RST_MCR	0x08000000	/* Reset FSI master reg. */
62#define FSI_MRESP_RST_PYE	0x04000000	/* Reset FSI parity error */
63#define FSI_MRESP_RST_ALL	0xfc000000	/* Reset any error */
64
65/* MECTRL: Error control */
66#define FSI_MECTRL_EOAE		0x8000		/* Enable machine check when */
67						/* master 0 in error */
68#define FSI_MECTRL_P8_AUTO_TERM	0x4000		/* Auto terminate */
69
70#define FSI_HUB_LINK_OFFSET		0x80000
71#define FSI_HUB_LINK_SIZE		0x80000
72#define FSI_HUB_MASTER_MAX_LINKS	8
73
74/*
75 * Protocol definitions
76 *
77 * These are used by low level masters that bit-bang out the protocol
78 */
79
80/* Various protocol delays */
81#define	FSI_ECHO_DELAY_CLOCKS	16	/* Number clocks for echo delay */
82#define	FSI_SEND_DELAY_CLOCKS	16	/* Number clocks for send delay */
83#define	FSI_PRE_BREAK_CLOCKS	50	/* Number clocks to prep for break */
84#define	FSI_BREAK_CLOCKS	256	/* Number of clocks to issue break */
85#define	FSI_POST_BREAK_CLOCKS	16000	/* Number clocks to set up cfam */
86#define	FSI_INIT_CLOCKS		5000	/* Clock out any old data */
87#define	FSI_MASTER_DPOLL_CLOCKS	50      /* < 21 will cause slave to hang */
88#define	FSI_MASTER_EPOLL_CLOCKS	50      /* Number of clocks for E_POLL retry */
89
90/* Various retry maximums */
91#define FSI_CRC_ERR_RETRIES	10
92#define	FSI_MASTER_MAX_BUSY	200
93#define	FSI_MASTER_MTOE_COUNT	1000
94
95/* Command encodings */
96#define	FSI_CMD_DPOLL		0x2
97#define	FSI_CMD_EPOLL		0x3
98#define	FSI_CMD_TERM		0x3f
99#define FSI_CMD_ABS_AR		0x4
100#define FSI_CMD_REL_AR		0x5
101#define FSI_CMD_SAME_AR		0x3	/* but only a 2-bit opcode... */
102
103/* Slave responses */
104#define	FSI_RESP_ACK		0	/* Success */
105#define	FSI_RESP_BUSY		1	/* Slave busy */
106#define	FSI_RESP_ERRA		2	/* Any (misc) Error */
107#define	FSI_RESP_ERRC		3	/* Slave reports master CRC error */
108
109/* Misc */
110#define	FSI_CRC_SIZE		4
111
112/* fsi-master definition and flags */
113#define FSI_MASTER_FLAG_SWCLOCK		0x1
114
115/*
116 * Structures and function prototypes
117 *
118 * These are common to all masters
119 */
120
121struct fsi_master {
122	struct device	dev;
123	int		idx;
124	int		n_links;
125	int		flags;
126	struct mutex	scan_lock;
127	int		(*read)(struct fsi_master *, int link, uint8_t id,
128				uint32_t addr, void *val, size_t size);
129	int		(*write)(struct fsi_master *, int link, uint8_t id,
130				uint32_t addr, const void *val, size_t size);
131	int		(*term)(struct fsi_master *, int link, uint8_t id);
132	int		(*send_break)(struct fsi_master *, int link);
133	int		(*link_enable)(struct fsi_master *, int link,
134				       bool enable);
135	int		(*link_config)(struct fsi_master *, int link,
136				       u8 t_send_delay, u8 t_echo_delay);
137};
138
139#define to_fsi_master(d) container_of(d, struct fsi_master, dev)
140
141/**
142 * fsi_master registration & lifetime: the fsi_master_register() and
143 * fsi_master_unregister() functions will take ownership of the master, and
144 * ->dev in particular. The registration path performs a get_device(), which
145 * takes the first reference on the device. Similarly, the unregistration path
146 * performs a put_device(), which may well drop the last reference.
147 *
148 * This means that master implementations *may* need to hold their own
149 * reference (via get_device()) on master->dev. In particular, if the device's
150 * ->release callback frees the fsi_master, then fsi_master_unregister will
151 * invoke this free if no other reference is held.
152 *
153 * The same applies for the error path of fsi_master_register; if the call
154 * fails, dev->release will have been invoked.
155 */
156extern int fsi_master_register(struct fsi_master *master);
157extern void fsi_master_unregister(struct fsi_master *master);
158
159extern int fsi_master_rescan(struct fsi_master *master);
160
161#endif /* DRIVERS_FSI_MASTER_H */
162