Fix PCI in Holly device tree

Josh Boyer jwboyer at linux.vnet.ibm.com
Thu Sep 25 22:11:29 EST 2008


On Thu, 25 Sep 2008 12:39:04 +1000
David Gibson <david at gibson.dropbear.id.au> wrote:

> The PCI bridge on the Holly board is current incorrectly represented
> in the device tree.  The current device tree node for the PCI bridge
> sits under the tsi-bridge node.  That's not obviously wrong, but the
> PCI bridge translated some PCI spaces into CPU address ranges which
> were not translated by the tsi-bridge node.
> 
> We used to get away with this problem because the PCI bridge discovery
> code was also buggy, assuming incorrectly that PCI host bridge nodes
> were always directly under the root bus and treating the translated
> addresses as raw CPU addresses, rather than parent bus addresses.
> This has since been fixed, breaking Holly.
> 
> This could be fixed by adding extra translations to the tsi-bridge
> node, but this patch instead moves the Holly PCI bridge out of the
> tsi-bridge node to the root bus.  This makes the tsi-bridge node
> represent only the built-in IO devices in the bridge, with a
> more-or-less contiguous address range.  This is the same convention
> used on Freescale SoC chips, where the "soc" node represents only the
> IMMR region, and the PCI and other bus bridges are separate nodes
> under the root bus.
> 
> Signed-off-by: David Gibson <david at gibson.dropbear.id.au>

Acked-by: Josh Boyer <jwboyer at linux.vnet.ibm.com>

Paul, I can include this in my 'next' branch if you aren't opposed.
I'll have another set of patches going in there today/tomorrow.

josh



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