[LinuxBIOS] Winflashrom -- Current Status

Stefan Reinauer stepan at coresystems.de
Fri Jul 13 12:52:19 CEST 2007

* Darmawan Salihun <darmawan.salihun at gmail.com> [070712 09:19]:
> Another note that I have difficulty in limiting the direct I/O access
> in the current driver because I don't know exactly which port to give
> access to and which one to block. Below is what I've found from the current
> flashrom code so far. I/O port usage:
>        0x2E (Winbond W836_INDEX port)
>        0x2F (Winbond W836_DATA port)
>        0x4E
>        0x4F

4e and 4f are superio ports, too

>        0xC6F
>        0xCD6
>        0xCD7

not sure. acpi something?

>        0xCFC - 0xCFF (PCI I/O port on x86)

>        a "base + 0x4D" in Via Epia motherboard
base is the interesting thing here.. It's determined dynamically.

>        0xE800 (what port is this? )
>        0xE801
>        0xE802
>        0xE803
>        0xE804
>        0xE807

I think these are hard codes of some legacy bios setting and should be
read dynamically, too..

>        0xE1
>        0xEB
>        0xFF

Wow, what are these?

I don't think you can easily limit this. I am working on support for a
board where the final IO address is read dynamically from PCI register
space. This might be required on more boards in the future.

>        I couldn't conclude the the I/O port ranges to open from the port
> list above because there is still unknown (I think it's dynamically 
> relocatable) I/O port such as the one used by EPIA board. 
> Any explanation on this issue?

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