pci-mvebu driver on km_kirkwood

Jason Gunthorpe jgunthorpe at obsidianresearch.com
Fri Feb 21 12:31:05 EST 2014

On Fri, Feb 21, 2014 at 06:05:08PM +0100, Thomas Petazzoni wrote:
> Now I have another question: our mvebu_pcie_align_resource() function
> makes sure that the base address of the BAR is aligned on its size,
> because it is a requirement of MBus windows. However, if you later
> split the BAR into multiple windows, will this continue to work out?

No, you must align to (1 << log2_round_down(size)) - that will always
be the largest mbus window created and thus the highest starting
alignment requirement.

I looked for a bit to see if I could find why the core is rounding up
to 196MB and it wasn't clear to me either.

Gerlando, if you instrument the code in setup-bus.c, particularly
pbus_size_mem, you will probably find out.


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