xref: /freebsd/sys/dev/imcsmb/imcsmb_var.h (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
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  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #ifndef _DEV__IMCSMB__IMCSMB_VAR_H_
34 #define _DEV__IMCSMB__IMCSMB_VAR_H_
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/module.h>
40 #include <sys/endian.h>
41 #include <sys/errno.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/syslog.h>
45 #include <sys/bus.h>
46 
47 #include <machine/bus.h>
48 #include <machine/atomic.h>
49 
50 #include <dev/pci/pcivar.h>
51 #include <dev/pci/pcireg.h>
52 
53 #include <dev/smbus/smbconf.h>
54 
55 #include "smbus_if.h"
56 
57 /* A detailed description of this device is present in imcsmb_pci.c */
58 
59 /**
60  * The softc for a particular instance of the PCI device associated with a pair
61  * of iMC-SMB controllers.
62  *
63  * Ordinarily, locking would be done with a mutex. However, we might have an
64  * NVDIMM connected to this SMBus, and we might need to issue the SAVE command
65  * to the NVDIMM from a panic context. Mutex operations are not allowed while
66  * the scheduler is stopped, so just use a simple semaphore.
67  *
68  * If, as described in the manpage, additional steps are needed to stop/restart
69  * firmware operations before/after using the controller, then additional fields
70  * can be added to this softc.
71  */
72 struct imcsmb_pci_softc {
73 	device_t dev;
74 	volatile int semaphore;
75 };
76 
77 void imcsmb_pci_release_bus(device_t dev);
78 int imcsmb_pci_request_bus(device_t dev);
79 
80 /**
81  * PCI config registers for each individual SMBus controller within the iMC.
82  * Each iMC-SMB has a separate set of registers. There is an array of these
83  * structures for the PCI device, and one of them is passed to driver for the
84  * actual iMC-SMB as the IVAR.
85  */
86 struct imcsmb_reg_set {
87 	uint16_t smb_stat;
88 	uint16_t smb_cmd;
89 	uint16_t smb_cntl;
90 };
91 
92 /**
93  * The softc for the device associated with a particular iMC-SMB controller.
94  * There are two such controllers for each of the PCI devices. The PCI driver
95  * tells the iMC-SMB driver which set of registers to use via the IVAR. This
96  * technique was suggested by John Baldwin (jhb@).
97  */
98 struct imcsmb_softc {
99 	device_t dev;
100 	device_t imcsmb_pci;	/* The SMBus controller's parent iMC */
101 	device_t smbus;		/* The child smbusX interface */
102 	struct imcsmb_reg_set *regs;	/* The registers this controller uses */
103 };
104 
105 #endif /* _DEV__IMCSMB__IMCSMB_VAR_H_ */
106 
107 /* vi: set ts=8 sw=4 sts=8 noet: */
108