On Thu, Aug 3, 2017 at 6:31 PM, Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> wrote: > On Thu 03 Aug 10:45 PDT 2017, Rob Herring wrote: > >> On Wed, Aug 2, 2017 at 9:57 PM, Bjorn Andersson >> <bjorn.andersson@xxxxxxxxxx> wrote: >> > In some cases drivers referencing a reserved-memory region might want to >> > remap the entire region, but when defining the reserved-memory by "size" >> > the client driver has no means to know the associated base address of >> > the reserved memory region. >> > >> > This patch adds an accessor for such drivers to acquire a handle to >> > their associated reserved-memory for this purpose. >> > >> > A complicating factor for the implementation is that the reserved_mem >> > objects are created from the flattened DeviceTree, as such we can't >> > use the device_node address for comparison. Fortunately the name of the >> > node will be used as "name" of the reserved_mem and will be used when >> > building the full_name, so we can compare the "name" with the basename >> > of the full_name to find the match. >> >> Maybe we should add the device_node pointer when we unflatten? >> > > It did try to figure something sane out in that direction. > > The solution I came up with was to amend populate_node() to in a !dryrun > block check if the "dad" full_name is /reserved-memory and if so > call call a new accessor in of_reserved_mem.c to add the "np" to the > reserved_mem object with fdt_node equal offset. I was thinking doing it with the unflattened tree just after it has been unflattened rather than during unflattening. > This code path is already cluttered due to the version differences when > it comes to building full_name and we would end up checking for each > node in the entire tree if the parent happens to be "/reserved-mem". > > So I went for the less intrusive and more straight forward comparison > with basename(full_name) instead. That's good, because full_name is about to become just the basename. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
