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
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	int		(*link_config)(struct fsi_master *, int link,
135				       u8 t_send_delay, u8 t_echo_delay);
136};
137
138#define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev)
139
140/**
141 * fsi_master registration & lifetime: the fsi_master_register() and
142 * fsi_master_unregister() functions will take ownership of the master, and
143 * ->dev in particular. The registration path performs a get_device(), which
144 * takes the first reference on the device. Similarly, the unregistration path
145 * performs a put_device(), which may well drop the last reference.
146 *
147 * This means that master implementations *may* need to hold their own
148 * reference (via get_device()) on master->dev. In particular, if the device's
149 * ->release callback frees the fsi_master, then fsi_master_unregister will
150 * invoke this free if no other reference is held.
151 *
152 * The same applies for the error path of fsi_master_register; if the call
153 * fails, dev->release will have been invoked.
154 */
155extern int fsi_master_register(struct fsi_master *master);
156extern void fsi_master_unregister(struct fsi_master *master);
157
158extern int fsi_master_rescan(struct fsi_master *master);
159
160#endif /* DRIVERS_FSI_MASTER_H */