Re: [PATCH] [POWERPC] 85xx: Add basic Uniprocessor MPC8572 DS port
From: Kumar Gala <hidden>
Date: 2007-09-12 03:32:20
On Sep 11, 2007, at 10:00 PM, David Gibson wrote:
On Tue, Sep 11, 2007 at 12:59:22PM -0500, Kumar Gala wrote:quoted
On Sep 11, 2007, at 12:48 PM, Scott Wood wrote:quoted
Olof Johansson wrote:quoted
On Tue, Sep 11, 2007 at 12:21:30PM -0500, Scott Wood wrote:quoted
Olof Johansson wrote:quoted
On Tue, Sep 11, 2007 at 11:00:28AM -0500, Kumar Gala wrote:quoted
well the ifdefs are orthogonal. We don't have a way of knowing primary from the device tree today.How about something like "fsl,primary-phb" in the bus device node? I don't know, maybe it's already been discussed and turned down for some reason.It's more of a Linux issue than anything to do with the hardware.That doesn't stop firmware from telling linux which bus is the primary one on the system to help out.The entire notion of a "primary" PCI bus is due to a Linux flaw. If we did put it in the device tree, it should be something like "linux,primary-phb". But since Linux can tell from the node's children, there doesn't seem to be much point.Once someone rights code to do this I'm happy to change over. I took this model of explicitly knowing the primary PHB from the pmac code.In the meantime, couldn't the code still be merged, using an explicit test of the root node's 'compatible' or 'model' properties to decide on the right primary bus.
I will be, I'm not going to wait on having some device tree spec for this. The board code can handle it until we come to some agreement on how to do this. I'm in agreement with Scott in that code should be added to scan or allow explicit determination. Adding a 'prop' to the device tree just for linux seems a bit silly. - k