xref: /freebsd/sys/dev/pci/fixup_pci.c (revision e0c4386e7e71d93b0edc0c8fa156263fc4a8b0b6)
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/param.h>
34 #include <sys/kernel.h>
35 #include <sys/malloc.h>
36 #include <sys/module.h>
37 #include <sys/systm.h>
38 #include <sys/bus.h>
39 
40 #include <dev/pci/pcivar.h>
41 #include <dev/pci/pcireg.h>
42 
43 /*
44  * Chipset fixups.
45  *
46  * These routines are invoked during the probe phase for devices which
47  * typically don't have specific device drivers, but which require
48  * some cleaning up.
49  */
50 
51 static int	fixup_pci_probe(device_t dev);
52 static void	fixwsc_natoma(device_t dev);
53 static void	fixc1_nforce2(device_t dev);
54 
55 static device_method_t fixup_pci_methods[] = {
56     /* Device interface */
57     DEVMETHOD(device_probe,		fixup_pci_probe),
58     DEVMETHOD(device_attach,		bus_generic_attach),
59     { 0, 0 }
60 };
61 
62 static driver_t fixup_pci_driver = {
63     "fixup_pci",
64     fixup_pci_methods,
65     0,
66 };
67 
68 DRIVER_MODULE(fixup_pci, pci, fixup_pci_driver, 0, 0);
69 
70 static int
71 fixup_pci_probe(device_t dev)
72 {
73     switch (pci_get_devid(dev)) {
74     case 0x12378086:		/* Intel 82440FX (Natoma) */
75 	fixwsc_natoma(dev);
76 	break;
77     case 0x01e010de:		/* nVidia nForce2 */
78 	fixc1_nforce2(dev);
79 	break;
80     }
81     return(ENXIO);
82 }
83 
84 static void
85 fixwsc_natoma(device_t dev)
86 {
87     int		pmccfg;
88 
89     pmccfg = pci_read_config(dev, 0x50, 2);
90 #if defined(SMP)
91     if (pmccfg & 0x8000) {
92 	device_printf(dev, "correcting Natoma config for SMP\n");
93 	pmccfg &= ~0x8000;
94 	pci_write_config(dev, 0x50, pmccfg, 2);
95     }
96 #else
97     if ((pmccfg & 0x8000) == 0) {
98 	device_printf(dev, "correcting Natoma config for non-SMP\n");
99 	pmccfg |= 0x8000;
100 	pci_write_config(dev, 0x50, pmccfg, 2);
101     }
102 #endif
103 }
104 
105 /*
106  * Set the SYSTEM_IDLE_TIMEOUT to 80 ns on nForce2 systems to work
107  * around a hang that is triggered when the CPU generates a very fast
108  * CONNECT/HALT cycle sequence.  Specifically, the hang can result in
109  * the lapic timer being stopped.
110  *
111  * This requires changing the value for config register at offset 0x6c
112  * for the Host-PCI bridge at bus/dev/function 0/0/0:
113  *
114  * Chip	Current Value	New Value
115  * ----	----------	----------
116  * C17	0x1F0FFF01	0x1F01FF01
117  * C18D	0x9F0FFF01	0x9F01FF01
118  *
119  * We do this by always clearing the bits in 0x000e0000.
120  *
121  * See also: http://lkml.org/lkml/2004/5/3/157
122  */
123 static void
124 fixc1_nforce2(device_t dev)
125 {
126 	uint32_t val;
127 
128 	if (pci_get_bus(dev) == 0 && pci_get_slot(dev) == 0 &&
129 	    pci_get_function(dev) == 0) {
130 		val = pci_read_config(dev, 0x6c, 4);
131 		if (val & 0x000e0000) {
132 			device_printf(dev,
133 			    "correcting nForce2 C1 CPU disconnect hangs\n");
134 			val &= ~0x000e0000;
135 			pci_write_config(dev, 0x6c, val, 4);
136 		}
137 	}
138 }
139