[v2] powerpc/powernv/pci-ioda: fix 32-bit TCE table init in kdump kernel

[Michael Ellerman]

On Wed, 2015-02-09 at 15:39:28 UTC, Nishanth Aravamudan wrote:
> When attempting to kdump with the 4.2 kernel, we see for each PCI
> device:
> 
>  pci 0003:01     : [PE# 000] Assign DMA32 space
>  pci 0003:01     : [PE# 000] Setting up 32-bit TCE table at 0..80000000
>  pci 0003:01     : [PE# 000] Failed to create 32-bit TCE table, err -22

<snip>

> is a valid sanity check for pnv_pci_ioda2_table_alloc_pages(), so adjust
> the caller to pass in a smaller window size if our maximum memory value
> is smaller than the DMA window.
> 
> After this change, the PCI devices successfully set up the 32-bit TCE
> table and kdump succeeds.
> 
> The problem was seen on a Firestone machine originally.
>     
> Fixes: aca6913f5551 ("powerpc/powernv/ioda2: Introduce helpers to allocate TCE pages")
> Signed-off-by: Nishanth Aravamudan <nacc at linux.vnet.ibm.com>
> Reviewed-by: Alexey Kardashevskiy <aik at ozlabs.ru>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/bb0054552d080dd929907c59

cheers