On Tue, Nov 24, 2009 at 2:06 PM, Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> wrote: > On Tue, 2009-11-24 at 09:37 -0800, David Miller wrote: >> From: Grant Likely <grant.likely@xxxxxxxxxxxx> >> Date: Tue, 24 Nov 2009 01:20:05 -0700 >> >> > In struct device_node, the phandle is named 'linux_phandle' for PowerPC >> > and MicroBlaze, and 'node' for SPARC. There is no good reason for the >> > difference, it is just an artifact of the code diverging over a couple >> > of years. This patch renames .node to .linux_phandle for SPARC. >> >> I know it's just a name, but there is no reason to put "linux" in the >> member name. It's the real device phandle value from OpenFirmware not >> something invented by Linux's OF layer. >> >> PowerPC uses this for something different, it records the information >> here using the special "linux,phandle" and "ibm,phandle" properties. >> >> See unflatten_dt_node() in arch/powerpc/kernel/prom.c before your >> changes. > > Right, this comes from a subtle problem with our firmwares on pSeries. > > We have a phandle from OF. But some devices, especially virtual devices, > also have an "ibm,phandle" which may or may not be the same afaik. > > In addition, when the hypervisor hotplugs some devices, it sends us some > new device-tree bits to add. Those don't have a phandle in the formal > sense afaik, but -do- have an ibm,phandle property. > > I think we can always just use ibm,phandle instead of the OF one when > the former is present, they should be non overlapping, but of course, > any chance in that area will require plenty of testing on some of those > machines. If pseries is the troublesome platform, not powermac, then I'm pretty confident this change is okay. I cannot find any other users of .node other than arch/powerpc/platforms/powermac/pfunc_core.c, but I'll double check with an allmodconfig and an allyesconfig. This patch shouldn't change the behaviour of linux_phandle at all. g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
