1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * ipmi_si_pci.c
4 *
5 * Handling for IPMI devices on the PCI bus.
6 */
7
8#define pr_fmt(fmt) "ipmi_pci: " fmt
9
10#include <linux/module.h>
11#include <linux/pci.h>
12#include "ipmi_si.h"
13
14static bool pci_registered;
15
16static bool si_trypci = true;
17
18module_param_named(trypci, si_trypci, bool, 0);
19MODULE_PARM_DESC(trypci,
20 "Setting this to zero will disable the default scan of the interfaces identified via pci");
21
22#define PCI_DEVICE_ID_HP_MMC 0x121A
23
24static int ipmi_pci_probe_regspacing(struct si_sm_io *io)
25{
26 if (io->si_type == SI_KCS) {
27 unsigned char status;
28 int regspacing;
29
30 io->regsize = DEFAULT_REGSIZE;
31 io->regshift = 0;
32
33 /* detect 1, 4, 16byte spacing */
34 for (regspacing = DEFAULT_REGSPACING; regspacing <= 16;) {
35 io->regspacing = regspacing;
36 if (io->io_setup(io)) {
37 dev_err(io->dev, "Could not setup I/O space\n");
38 return DEFAULT_REGSPACING;
39 }
40 /* write invalid cmd */
41 io->outputb(io, 1, 0x10);
42 /* read status back */
43 status = io->inputb(io, 1);
44 io->io_cleanup(io);
45 if (status)
46 return regspacing;
47 regspacing *= 4;
48 }
49 }
50 return DEFAULT_REGSPACING;
51}
52
53static struct pci_device_id ipmi_pci_blacklist[] = {
54 /*
55 * This is a "Virtual IPMI device", whatever that is. It appears
56 * as a KCS device by the class, but it is not one.
57 */
58 { PCI_VDEVICE(REALTEK, 0x816c) },
59 { 0, }
60};
61
62static int ipmi_pci_probe(struct pci_dev *pdev,
63 const struct pci_device_id *ent)
64{
65 int rv;
66 struct si_sm_io io;
67
68 if (pci_match_id(ids: ipmi_pci_blacklist, dev: pdev))
69 return -ENODEV;
70
71 memset(&io, 0, sizeof(io));
72 io.addr_source = SI_PCI;
73 dev_info(&pdev->dev, "probing via PCI");
74
75 switch (pdev->class) {
76 case PCI_CLASS_SERIAL_IPMI_SMIC:
77 io.si_type = SI_SMIC;
78 break;
79
80 case PCI_CLASS_SERIAL_IPMI_KCS:
81 io.si_type = SI_KCS;
82 break;
83
84 case PCI_CLASS_SERIAL_IPMI_BT:
85 io.si_type = SI_BT;
86 break;
87
88 default:
89 dev_info(&pdev->dev, "Unknown IPMI class: %x\n", pdev->class);
90 return -ENOMEM;
91 }
92
93 rv = pcim_enable_device(pdev);
94 if (rv) {
95 dev_err(&pdev->dev, "couldn't enable PCI device\n");
96 return rv;
97 }
98
99 if (pci_resource_flags(pdev, 0) & IORESOURCE_IO) {
100 io.addr_space = IPMI_IO_ADDR_SPACE;
101 io.io_setup = ipmi_si_port_setup;
102 } else {
103 io.addr_space = IPMI_MEM_ADDR_SPACE;
104 io.io_setup = ipmi_si_mem_setup;
105 }
106 io.addr_data = pci_resource_start(pdev, 0);
107
108 io.dev = &pdev->dev;
109
110 io.regspacing = ipmi_pci_probe_regspacing(io: &io);
111 io.regsize = DEFAULT_REGSIZE;
112 io.regshift = 0;
113
114 io.irq = pdev->irq;
115 if (io.irq)
116 io.irq_setup = ipmi_std_irq_setup;
117
118 dev_info(&pdev->dev, "%pR regsize %d spacing %d irq %d\n",
119 &pdev->resource[0], io.regsize, io.regspacing, io.irq);
120
121 return ipmi_si_add_smi(io: &io);
122}
123
124static void ipmi_pci_remove(struct pci_dev *pdev)
125{
126 ipmi_si_remove_by_dev(dev: &pdev->dev);
127}
128
129static const struct pci_device_id ipmi_pci_devices[] = {
130 { PCI_VDEVICE(HP, PCI_DEVICE_ID_HP_MMC) },
131 { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_IPMI_SMIC, ~0) },
132 { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_IPMI_KCS, ~0) },
133 { PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_IPMI_BT, ~0) },
134 { 0, }
135};
136MODULE_DEVICE_TABLE(pci, ipmi_pci_devices);
137
138static struct pci_driver ipmi_pci_driver = {
139 .name = SI_DEVICE_NAME,
140 .id_table = ipmi_pci_devices,
141 .probe = ipmi_pci_probe,
142 .remove = ipmi_pci_remove,
143};
144
145void ipmi_si_pci_init(void)
146{
147 if (si_trypci) {
148 int rv = pci_register_driver(&ipmi_pci_driver);
149 if (rv)
150 pr_err("Unable to register PCI driver: %d\n", rv);
151 else
152 pci_registered = true;
153 }
154}
155
156void ipmi_si_pci_shutdown(void)
157{
158 if (pci_registered)
159 pci_unregister_driver(dev: &ipmi_pci_driver);
160}
161

source code of linux/drivers/char/ipmi/ipmi_si_pci.c