Problems with PCI on 8280

Rune Torgersen runet at
Fri Jan 18 11:27:46 EST 2008

From: Scott Wood

>Hmm...  that suggests that something in u-boot's setup is either 
>incorrect, or (more likely in this case) doesn't match the device tree.

Turns out u-boot was not setting u the inbound window size correctly.
It was hardcoded to 512MB and we have a gig of ram. Set it correctly, and CPI now works fully even without fixup_pci()

>Ah.  Yes, I was assuming both windows would be the same size.  The code 
>should be changed to check that, and if any conditions for setting 
>PCIBRx/PCIMSKx fail, check to see if the firmware-provided values work 
>(and if not, bail without touching anything).

yup. In our case we only need one window.

BTW. there is a bug in the inbound window size calculation.
The mem_log2 variable sould be the shift value, not 1<< shift.
and on the next line the window size mask sould be anded with 0x000f_ffff before or'ed with 0xa000_0000

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