xref: /freebsd/sys/dev/pci/fixup_pci.c (revision 6829dae12bb055451fa467da4589c43bd03b1e64)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1994,1995 Stefan Esser, Wolfgang StanglMeier
5  * Copyright (c) 2000 Michael Smith <msmith@freebsd.org>
6  * Copyright (c) 2000 BSDi
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  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/module.h>
40 #include <sys/systm.h>
41 #include <sys/bus.h>
42 
43 #include <dev/pci/pcivar.h>
44 #include <dev/pci/pcireg.h>
45 
46 /*
47  * Chipset fixups.
48  *
49  * These routines are invoked during the probe phase for devices which
50  * typically don't have specific device drivers, but which require
51  * some cleaning up.
52  */
53 
54 static int	fixup_pci_probe(device_t dev);
55 static void	fixwsc_natoma(device_t dev);
56 static void	fixc1_nforce2(device_t dev);
57 
58 static device_method_t fixup_pci_methods[] = {
59     /* Device interface */
60     DEVMETHOD(device_probe,		fixup_pci_probe),
61     DEVMETHOD(device_attach,		bus_generic_attach),
62     { 0, 0 }
63 };
64 
65 static driver_t fixup_pci_driver = {
66     "fixup_pci",
67     fixup_pci_methods,
68     0,
69 };
70 
71 static devclass_t fixup_pci_devclass;
72 
73 DRIVER_MODULE(fixup_pci, pci, fixup_pci_driver, fixup_pci_devclass, 0, 0);
74 
75 static int
76 fixup_pci_probe(device_t dev)
77 {
78     switch (pci_get_devid(dev)) {
79     case 0x12378086:		/* Intel 82440FX (Natoma) */
80 	fixwsc_natoma(dev);
81 	break;
82     case 0x01e010de:		/* nVidia nForce2 */
83 	fixc1_nforce2(dev);
84 	break;
85     }
86     return(ENXIO);
87 }
88 
89 static void
90 fixwsc_natoma(device_t dev)
91 {
92     int		pmccfg;
93 
94     pmccfg = pci_read_config(dev, 0x50, 2);
95 #if defined(SMP)
96     if (pmccfg & 0x8000) {
97 	device_printf(dev, "correcting Natoma config for SMP\n");
98 	pmccfg &= ~0x8000;
99 	pci_write_config(dev, 0x50, pmccfg, 2);
100     }
101 #else
102     if ((pmccfg & 0x8000) == 0) {
103 	device_printf(dev, "correcting Natoma config for non-SMP\n");
104 	pmccfg |= 0x8000;
105 	pci_write_config(dev, 0x50, pmccfg, 2);
106     }
107 #endif
108 }
109 
110 /*
111  * Set the SYSTEM_IDLE_TIMEOUT to 80 ns on nForce2 systems to work
112  * around a hang that is triggered when the CPU generates a very fast
113  * CONNECT/HALT cycle sequence.  Specifically, the hang can result in
114  * the lapic timer being stopped.
115  *
116  * This requires changing the value for config register at offset 0x6c
117  * for the Host-PCI bridge at bus/dev/function 0/0/0:
118  *
119  * Chip	Current Value	New Value
120  * ----	----------	----------
121  * C17	0x1F0FFF01	0x1F01FF01
122  * C18D	0x9F0FFF01	0x9F01FF01
123  *
124  * We do this by always clearing the bits in 0x000e0000.
125  *
126  * See also: http://lkml.org/lkml/2004/5/3/157
127  */
128 static void
129 fixc1_nforce2(device_t dev)
130 {
131 	uint32_t val;
132 
133 	if (pci_get_bus(dev) == 0 && pci_get_slot(dev) == 0 &&
134 	    pci_get_function(dev) == 0) {
135 		val = pci_read_config(dev, 0x6c, 4);
136 		if (val & 0x000e0000) {
137 			device_printf(dev,
138 			    "correcting nForce2 C1 CPU disconnect hangs\n");
139 			val &= ~0x000e0000;
140 			pci_write_config(dev, 0x6c, val, 4);
141 		}
142 	}
143 }
144