1 =======================
2 Kernel driver i2c-piix4
3 =======================
4
5 Supported adapters:
6 * Intel 82371AB PIIX4 and PIIX4E
7 * Intel 82443MX (440MX)
8 Datasheet: Publicly available at the Intel
9 * ServerWorks OSB4, CSB5, CSB6, HT-1000 and
10 Datasheet: Only available via NDA from Ser
11 * ATI IXP200, IXP300, IXP400, SB600, SB700 a
12 Datasheet: Not publicly available
13 SB700 register reference available at:
14 http://support.amd.com/us/Embedded_TechDoc
15 * AMD SP5100 (SB700 derivative found on some
16 Datasheet: Publicly available at the AMD w
17 http://support.amd.com/us/Embedded_TechDoc
18 * AMD Hudson-2, ML, CZ
19 Datasheet: Not publicly available
20 * Hygon CZ
21 Datasheet: Not publicly available
22 * Standard Microsystems (SMSC) SLC90E66 (Vic
23 Datasheet: Publicly available at the SMSC
24
25 Authors:
26 - Frodo Looijaard <frodol@dds.nl>
27 - Philip Edelbrock <phil@netroedge.com>
28
29
30 Module Parameters
31 -----------------
32
33 * force: int
34 Forcibly enable the PIIX4. DANGEROUS!
35 * force_addr: int
36 Forcibly enable the PIIX4 at the given addre
37
38
39 Description
40 -----------
41
42 The PIIX4 (properly known as the 82371AB) is a
43 functionality. Among other things, it implemen
44 minor functions is implementing a System Manag
45 SMBus - you can not access it on I2C levels. T
46 natively understands SMBus commands and you do
47 timing problems. The bad news is that non-SMBu
48 confuse it mightily. Yes, this is known to hap
49
50 Do ``lspci -v`` and see whether it contains an
51
52 0000:00:02.3 Bridge: Intel Corp. 82371AB/EB/
53 Flags: medium devsel, IRQ 9
54
55 Bus and device numbers may differ, but the fun
56 identical (like many PCI devices, the PIIX4 in
57 different 'functions', which can be considered
58 find such an entry, you have a PIIX4 SMBus con
59
60 On some computers (most notably, some Dells),
61 default. If you use the insmod parameter 'forc
62 try to enable it. THIS IS VERY DANGEROUS! If t
63 correct address for this module, you could get
64 crashes, data corruption, etc.). Try this only
65 updates first, for example), and backup first!
66 option is 'force_addr=<IOPORT>'. This will not
67 'force' does, but it will also set a new base
68 parts of the PIIX4 needs a range of 8 of these
69 correctly. If these addresses are already rese
70 you will get into big trouble! DON'T USE THIS
71 ABOUT WHAT YOU ARE DOING!
72
73 The PIIX4E is just an new version of the PIIX4
74 The PIIX/PIIX3 does not implement an SMBus or
75 this driver on those mainboards.
76
77 The ServerWorks Southbridges, the Intel 440MX,
78 identical to the PIIX4 in I2C/SMBus support.
79
80 The AMD SB700, SB800, SP5100 and Hudson-2 chip
81 PIIX4-compatible SMBus controllers. If your BI
82 secondary controller, it will be detected by t
83 an "Auxiliary SMBus Host Controller".
84
85 If you own Force CPCI735 motherboard or other
86 to change the SMBus Interrupt Select register
87 the SMI mode.
88
89 1) Use ``lspci`` command and locate the PCI de
90 00:0f.0 ISA bridge: ServerWorks OSB4 South
91 The line may vary for different chipsets. P
92 for all possible PCI ids (and ``lspci -n``
93 device is located at 00:0f.0.
94 2) Now you just need to change the value in 0x
95 command: ``lspci -xxx -s 00:0f.0``
96 If the value is 0x3 then you need to change
97 ``setpci -s 00:0f.0 d2.b=1``
98
99 Please note that you don't need to do that in
100 not working properly.
101
102
103 Hardware-specific issues
104 ------------------------
105
106 This driver will refuse to load on IBM systems
107 Some of these machines have an RFID EEPROM (24
108 which can easily get corrupted due to a state
109 Thinkpad laptops, but desktop systems may also
110 of all affected systems, so the only safe solu
111 the SMBus on all IBM systems (detected using D
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