1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Authors: Joe Kloss; Ravi Pokala (rpokala@freebsd.org)
5 *
6 * Copyright (c) 2017-2018 Panasas
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: stable/11/sys/dev/imcsmb/imcsmb_var.h 355366 2019-12-03 22:53:50Z rpokala $
30 */
31
32#ifndef _DEV__IMCSMB__IMCSMB_VAR_H_
33#define _DEV__IMCSMB__IMCSMB_VAR_H_
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38#include <sys/module.h>
39#include <sys/endian.h>
40#include <sys/errno.h>
41#include <sys/lock.h>
42#include <sys/mutex.h>
43#include <sys/syslog.h>
44#include <sys/bus.h>
45
46#include <machine/bus.h>
47#include <machine/atomic.h>
48
49#include <dev/pci/pcivar.h>
50#include <dev/pci/pcireg.h>
51
52#include <dev/smbus/smbconf.h>
53
54#include "smbus_if.h"
55
56/* A detailed description of this device is present in imcsmb_pci.c */
57
58/**
59 * The softc for a particular instance of the PCI device associated with a pair
60 * of iMC-SMB controllers.
61 *
62 * Ordinarily, locking would be done with a mutex. However, we might have an
63 * NVDIMM connected to this SMBus, and we might need to issue the SAVE command
64 * to the NVDIMM from a panic context. Mutex operations are not allowed while
65 * the scheduler is stopped, so just use a simple semaphore.
66 *
67 * If, as described in the manpage, additional steps are needed to stop/restart
68 * firmware operations before/after using the controller, then additional fields
69 * can be added to this softc.
70 */
71struct imcsmb_pci_softc {
72	device_t dev;
73	volatile int semaphore;
74};
75
76void imcsmb_pci_release_bus(device_t dev);
77int imcsmb_pci_request_bus(device_t dev);
78
79/**
80 * PCI config registers for each individual SMBus controller within the iMC.
81 * Each iMC-SMB has a separate set of registers. There is an array of these
82 * structures for the PCI device, and one of them is passed to driver for the
83 * actual iMC-SMB as the IVAR.
84 */
85struct imcsmb_reg_set {
86	uint16_t smb_stat;
87	uint16_t smb_cmd;
88	uint16_t smb_cntl;
89};
90
91/**
92 * The softc for the device associated with a particular iMC-SMB controller.
93 * There are two such controllers for each of the PCI devices. The PCI driver
94 * tells the iMC-SMB driver which set of registers to use via the IVAR. This
95 * technique was suggested by John Baldwin (jhb@).
96 */
97struct imcsmb_softc {
98	device_t dev;
99	device_t imcsmb_pci;	/* The SMBus controller's parent iMC */
100	device_t smbus;		/* The child smbusX interface */
101	struct imcsmb_reg_set *regs;	/* The registers this controller uses */
102};
103
104#endif /* _DEV__IMCSMB__IMCSMB_VAR_H_ */
105
106/* vi: set ts=8 sw=4 sts=8 noet: */
107