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Diffstat (limited to 'Documentation/i2c/busses/i2c-piix4')
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diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4 deleted file mode 100644 index 2703bc3acad0..000000000000 --- a/Documentation/i2c/busses/i2c-piix4 +++ /dev/null @@ -1,112 +0,0 @@ -Kernel driver i2c-piix4 - -Supported adapters: - * Intel 82371AB PIIX4 and PIIX4E - * Intel 82443MX (440MX) - Datasheet: Publicly available at the Intel website - * ServerWorks OSB4, CSB5, CSB6, HT-1000 and HT-1100 southbridges - Datasheet: Only available via NDA from ServerWorks - * ATI IXP200, IXP300, IXP400, SB600, SB700 and SB800 southbridges - Datasheet: Not publicly available - SB700 register reference available at: - http://support.amd.com/us/Embedded_TechDocs/43009_sb7xx_rrg_pub_1.00.pdf - * AMD SP5100 (SB700 derivative found on some server mainboards) - Datasheet: Publicly available at the AMD website - http://support.amd.com/us/Embedded_TechDocs/44413.pdf - * AMD Hudson-2, ML, CZ - Datasheet: Not publicly available - * Hygon CZ - Datasheet: Not publicly available - * Standard Microsystems (SMSC) SLC90E66 (Victory66) southbridge - Datasheet: Publicly available at the SMSC website http://www.smsc.com - -Authors: - Frodo Looijaard <frodol@dds.nl> - Philip Edelbrock <phil@netroedge.com> - - -Module Parameters ------------------ - -* force: int - Forcibly enable the PIIX4. DANGEROUS! -* force_addr: int - Forcibly enable the PIIX4 at the given address. EXTREMELY DANGEROUS! - - -Description ------------ - -The PIIX4 (properly known as the 82371AB) is an Intel chip with a lot of -functionality. Among other things, it implements the PCI bus. One of its -minor functions is implementing a System Management Bus. This is a true -SMBus - you can not access it on I2C levels. The good news is that it -natively understands SMBus commands and you do not have to worry about -timing problems. The bad news is that non-SMBus devices connected to it can -confuse it mightily. Yes, this is known to happen... - -Do 'lspci -v' and see whether it contains an entry like this: - -0000:00:02.3 Bridge: Intel Corp. 82371AB/EB/MB PIIX4 ACPI (rev 02) - Flags: medium devsel, IRQ 9 - -Bus and device numbers may differ, but the function number must be -identical (like many PCI devices, the PIIX4 incorporates a number of -different 'functions', which can be considered as separate devices). If you -find such an entry, you have a PIIX4 SMBus controller. - -On some computers (most notably, some Dells), the SMBus is disabled by -default. If you use the insmod parameter 'force=1', the kernel module will -try to enable it. THIS IS VERY DANGEROUS! If the BIOS did not set up a -correct address for this module, you could get in big trouble (read: -crashes, data corruption, etc.). Try this only as a last resort (try BIOS -updates first, for example), and backup first! An even more dangerous -option is 'force_addr=<IOPORT>'. This will not only enable the PIIX4 like -'force' foes, but it will also set a new base I/O port address. The SMBus -parts of the PIIX4 needs a range of 8 of these addresses to function -correctly. If these addresses are already reserved by some other device, -you will get into big trouble! DON'T USE THIS IF YOU ARE NOT VERY SURE -ABOUT WHAT YOU ARE DOING! - -The PIIX4E is just an new version of the PIIX4; it is supported as well. -The PIIX/PIIX3 does not implement an SMBus or I2C bus, so you can't use -this driver on those mainboards. - -The ServerWorks Southbridges, the Intel 440MX, and the Victory66 are -identical to the PIIX4 in I2C/SMBus support. - -The AMD SB700, SB800, SP5100 and Hudson-2 chipsets implement two -PIIX4-compatible SMBus controllers. If your BIOS initializes the -secondary controller, it will be detected by this driver as -an "Auxiliary SMBus Host Controller". - -If you own Force CPCI735 motherboard or other OSB4 based systems you may need -to change the SMBus Interrupt Select register so the SMBus controller uses -the SMI mode. - -1) Use lspci command and locate the PCI device with the SMBus controller: - 00:0f.0 ISA bridge: ServerWorks OSB4 South Bridge (rev 4f) - The line may vary for different chipsets. Please consult the driver source - for all possible PCI ids (and lspci -n to match them). Lets assume the - device is located at 00:0f.0. -2) Now you just need to change the value in 0xD2 register. Get it first with - command: lspci -xxx -s 00:0f.0 - If the value is 0x3 then you need to change it to 0x1 - setpci -s 00:0f.0 d2.b=1 - -Please note that you don't need to do that in all cases, just when the SMBus is -not working properly. - - -Hardware-specific issues ------------------------- - -This driver will refuse to load on IBM systems with an Intel PIIX4 SMBus. -Some of these machines have an RFID EEPROM (24RF08) connected to the SMBus, -which can easily get corrupted due to a state machine bug. These are mostly -Thinkpad laptops, but desktop systems may also be affected. We have no list -of all affected systems, so the only safe solution was to prevent access to -the SMBus on all IBM systems (detected using DMI data.) - -For additional information, read: -http://www.lm-sensors.org/browser/lm-sensors/trunk/README |