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Date: Tue, 18 Sep 2007 16:03:50 +0400
From: Valentine Barshak <vbarshak@ru.mvista.com>
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To: Vitaly Bordug <vitb@kernel.crashing.org>
Subject: Re: [PATCH] [RFC][POWERPC] Merge 32 and 64
	bit	pci_process_bridge_OF_ranges() instances
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Vitaly Bordug wrote:
> +
> +			hose->io_base_phys = cpu_phys_addr - pci_addr;

This is not gonna work on 32-bit platform (unless pci_addr == 0).
Should be
hose->io_base_phys = cpu_phys_addr;
The other way we should adjust io size like we do on 64-bit and rewrite 
resource fixup functions.

> +			/* handle from 0 to top of I/O window */
> +#ifdef CONFIG_PPC64
> +			hose->pci_io_size = pci_addr + size;
> +#endif
> +			hose->io_base_virt = ioremap(hose->io_base_phys, size);

Do we need to ioremap on 64-bit? I think 64-bit uses different approach 
in handling io space.

> +#ifdef CONFIG_PPC32
> +			if (prim)
> +				isa_io_base = (unsigned long)hose->io_base_virt;
> +#endif

What's exactly the point of merging this single function?
If this was intended to add 64-bit physical address support to 32-bit 
platforms (like ppc440), then it does not seem sufficient to make pci 
stuff work right.
What about the 32-bit pcibios_fixup_resources(), 
pcibios_resource_to_bus(), pcibios_bus_to_resource() stuff?
There's still no 64-bit support. You'll get
"PCI Cannot allocate resource region" attempting to initialize resources 
at PCI start-up.
Thanks,
Valentine.