[coreboot] Dump GPIO I/O Registers

joe at smittys.pointclark.net joe at smittys.pointclark.net
Tue Feb 19 01:45:55 CET 2008

Quoting Tom Sylla <tsylla at gmail.com>:

> If you want to look at the GPIOs, from the 82801DB datasheet, it looks
> like you should look at:
> 9.1.14 GPIOBASE—GPIO Base Address (LPC I/F—D31:F0)


> and
> 9.1.15 GPIO_CNTL—GPIO Control (LPC I/F—D31:F0)
> (offsets 58 and 5c in D31:f0, lspci -xxx as root is one way to dump)


> What value is in those registers? Check to see if an address is
> assigned, and if the decode is enabled. If so, you have something to
> dump.
> That register is not a real PCI BAR, so it may not show up in /proc/ioports
> Once you have the base address, you can read the GPIO control
> registers from /dev/port, with the seek equal to the base address.

How?? This is the part I am looking for, this would be the golden ticket:-)

> It
> looks like the register set is described in:
> 9.10 General Purpose I/O Registers (D31:F0)
> and Table 9-12 in the 82801DB datasheet.
Yup, that is what I am going to reference it with.

Thanks for you help Tom.

Thanks - Joe

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