mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 08:19:28 +00:00
![Benjamin Herrenschmidt](/assets/img/avatar_default.png)
The bus scanning process isn't terribly good at parallel attempts at rescanning the same bus. Let's have a per-master mutex protecting the scanning process. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
97 lines
3.6 KiB
C
97 lines
3.6 KiB
C
/*
|
|
* FSI master definitions. These comprise the core <--> master interface,
|
|
* to allow the core to interact with the (hardware-specific) masters.
|
|
*
|
|
* Copyright (C) IBM Corporation 2016
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*/
|
|
|
|
#ifndef DRIVERS_FSI_MASTER_H
|
|
#define DRIVERS_FSI_MASTER_H
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/mutex.h>
|
|
|
|
/* Various protocol delays */
|
|
#define FSI_ECHO_DELAY_CLOCKS 16 /* Number clocks for echo delay */
|
|
#define FSI_SEND_DELAY_CLOCKS 16 /* Number clocks for send delay */
|
|
#define FSI_PRE_BREAK_CLOCKS 50 /* Number clocks to prep for break */
|
|
#define FSI_BREAK_CLOCKS 256 /* Number of clocks to issue break */
|
|
#define FSI_POST_BREAK_CLOCKS 16000 /* Number clocks to set up cfam */
|
|
#define FSI_INIT_CLOCKS 5000 /* Clock out any old data */
|
|
#define FSI_MASTER_DPOLL_CLOCKS 50 /* < 21 will cause slave to hang */
|
|
#define FSI_MASTER_EPOLL_CLOCKS 50 /* Number of clocks for E_POLL retry */
|
|
|
|
/* Various retry maximums */
|
|
#define FSI_CRC_ERR_RETRIES 10
|
|
#define FSI_MASTER_MAX_BUSY 200
|
|
#define FSI_MASTER_MTOE_COUNT 1000
|
|
|
|
/* Command encodings */
|
|
#define FSI_CMD_DPOLL 0x2
|
|
#define FSI_CMD_EPOLL 0x3
|
|
#define FSI_CMD_TERM 0x3f
|
|
#define FSI_CMD_ABS_AR 0x4
|
|
#define FSI_CMD_REL_AR 0x5
|
|
#define FSI_CMD_SAME_AR 0x3 /* but only a 2-bit opcode... */
|
|
|
|
/* Slave responses */
|
|
#define FSI_RESP_ACK 0 /* Success */
|
|
#define FSI_RESP_BUSY 1 /* Slave busy */
|
|
#define FSI_RESP_ERRA 2 /* Any (misc) Error */
|
|
#define FSI_RESP_ERRC 3 /* Slave reports master CRC error */
|
|
|
|
/* Misc */
|
|
#define FSI_CRC_SIZE 4
|
|
|
|
/* fsi-master definition and flags */
|
|
#define FSI_MASTER_FLAG_SWCLOCK 0x1
|
|
|
|
struct fsi_master {
|
|
struct device dev;
|
|
int idx;
|
|
int n_links;
|
|
int flags;
|
|
struct mutex scan_lock;
|
|
int (*read)(struct fsi_master *, int link, uint8_t id,
|
|
uint32_t addr, void *val, size_t size);
|
|
int (*write)(struct fsi_master *, int link, uint8_t id,
|
|
uint32_t addr, const void *val, size_t size);
|
|
int (*term)(struct fsi_master *, int link, uint8_t id);
|
|
int (*send_break)(struct fsi_master *, int link);
|
|
int (*link_enable)(struct fsi_master *, int link);
|
|
int (*link_config)(struct fsi_master *, int link,
|
|
u8 t_send_delay, u8 t_echo_delay);
|
|
};
|
|
|
|
#define dev_to_fsi_master(d) container_of(d, struct fsi_master, dev)
|
|
|
|
/**
|
|
* fsi_master registration & lifetime: the fsi_master_register() and
|
|
* fsi_master_unregister() functions will take ownership of the master, and
|
|
* ->dev in particular. The registration path performs a get_device(), which
|
|
* takes the first reference on the device. Similarly, the unregistration path
|
|
* performs a put_device(), which may well drop the last reference.
|
|
*
|
|
* This means that master implementations *may* need to hold their own
|
|
* reference (via get_device()) on master->dev. In particular, if the device's
|
|
* ->release callback frees the fsi_master, then fsi_master_unregister will
|
|
* invoke this free if no other reference is held.
|
|
*
|
|
* The same applies for the error path of fsi_master_register; if the call
|
|
* fails, dev->release will have been invoked.
|
|
*/
|
|
extern int fsi_master_register(struct fsi_master *master);
|
|
extern void fsi_master_unregister(struct fsi_master *master);
|
|
|
|
extern int fsi_master_rescan(struct fsi_master *master);
|
|
|
|
#endif /* DRIVERS_FSI_MASTER_H */
|