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  
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 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