On Wed, Jul 16, 2014 at 5:12 PM, Nathan Fontenot <nf...@austin.ibm.com> wrote: > On 07/16/2014 05:26 PM, Grant Likely wrote: >> On Wed, Jul 16, 2014 at 2:57 PM, Grant Likely <grant.lik...@linaro.org> >> wrote: >>> On Wed, Jul 16, 2014 at 12:30 PM, Tyrel Datwyler >>> <turtle.in.the.ker...@gmail.com> wrote: >>>> On 07/15/2014 10:33 PM, Grant Likely wrote: >>>>> I've got another question about powerpc reconfiguration. I was looking >>>>> at the dlpar_configure_connector() function in dlpar.c. I see that the >>>>> function has the ability to process multiple nodes with additional >>>>> sibling and child nodes. It appears to link them into a detached tree >>>>> structure, and the function returns a pointer to the first node. >>>>> >>>>> All of the callers of that function then call dlpar_attach_node(), >>>>> which calls of_attach_node(). However, of_attach_node() only handles a >>>>> single node. It doesn't handle siblings or children. Is this a bug? >>>>> Does the configure connector ever actually receive more than one node >>>>> at once? >>>> >>>> Yes, it is sometimes the case we will get a tree structure back of more >>>> than one node. Under the proc interface implementation this just worked. >>>> With the move to sysfs it appears we have a regression here. What makes >>>> more sense here, for us to walk the tree calling of_attach_node, or to >>>> move such tree walking logic into of_attach_node? From what I can tell >>>> we are the only consumers of of_attach_node. >>> >>> That is very shortly going to change. The overlay code also uses >>> of_attach_node(). I can make of_attach_node() recurse over >>> descendants, but I'm also considering moving the powerpc code over to >>> the of_changeset series that Panto and I are working on. >>> >>> Either way, the handling of multiple nodes should be common code. I >>> think the easiest is to put the recursion into of_attach_node(), at >>> least for fixing the bug. It can be reworked later. >> >> On pseries, do notifiers ever fail? ie. Does the reconfig code ever >> object to a DT change and prevent it from being applied? >> > I cannot think of a time that I ever saw a notifier fail.
Good to know. I was hoping it wasn't part of the design. I can't think of any situation where the kernel would want to inhibit a change to the device tree. Can you take a look at the following tree and give it a spin on PowerPC. I've reordered the notifiers and hopefully got the powerpc fixups right, but I don't have a way to test it... The following changes since commit cd3de83f147601356395b57a8673e9c5ff1e59d1: Linux 3.16-rc4 (2014-07-06 12:37:51 -0700) are available in the git repository at: git://git.secretlab.ca/git/linux devicetree/next-overlay for you to fetch changes up to 44ac93bb5583c5f1f85912309fe04045b61a6dd0: of: Transactional DT support. (2014-07-16 16:44:07 -0600) ---------------------------------------------------------------- Grant Likely (6): of/platform: Fix of_platform_device_destroy iteration of devices of: Move CONFIG_OF_DYNAMIC code into a separate file of: Make sure attached nodes don't carry along extra children of: Move dynamic node fixups out of powerpc and into common code of: Make OF_DYNAMIC user selectable of: Reorder device tree changes and notifiers Pantelis Antoniou (5): of: rename of_aliases_mutex to just of_mutex OF: Utility helper functions for dynamic nodes of: Create unlocked versions of node and property add/remove functions of: Make devicetree sysfs update functions consistent. of: Transactional DT support. Documentation/devicetree/changesets.txt | 41 ++ arch/powerpc/kernel/prom.c | 70 --- arch/powerpc/platforms/pseries/hotplug-memory.c | 2 +- drivers/crypto/nx/nx-842.c | 30 +- drivers/of/Kconfig | 2 +- drivers/of/Makefile | 1 + drivers/of/base.c | 423 ++++----------- drivers/of/device.c | 4 +- drivers/of/dynamic.c | 671 ++++++++++++++++++++++++ drivers/of/of_private.h | 59 ++- drivers/of/platform.c | 32 +- drivers/of/selftest.c | 79 +++ drivers/of/testcase-data/testcases.dtsi | 10 + include/linux/of.h | 80 ++- include/linux/of_platform.h | 7 +- 15 files changed, 1067 insertions(+), 444 deletions(-) create mode 100644 Documentation/devicetree/changesets.txt create mode 100644 drivers/of/dynamic.c _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev