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 brindge */
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 
121 struct 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 dev_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  */
156 extern int fsi_master_register(struct fsi_master *master);
157 extern void fsi_master_unregister(struct fsi_master *master);
158 
159 extern int fsi_master_rescan(struct fsi_master *master);
160 
161 #endif /* DRIVERS_FSI_MASTER_H */
162