On Tue, May 5, 2015 at 3:29 PM, <maitysanchayan@xxxxxxxxx> wrote: > Thanks for the reply. Hmm... I did not think of a DT entry as it is a > single location and not part of any particular peripheral. Not even > mentioned in the memory map. That's why I suggested to use a syscon device. > I tried grepping for ioremap functions instead of devm ones and saw one > instance and I wrote mine like this > > rom_rev = ioremap(ROM_REVISION_REGISTER, SZ_1); > if (rom_rev) > soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%08x", > readl(rom_rev)); > > Is something like this valid? Or use of devm_* functions is > recommeneded? Since this ioremap is gonna be called from a function > which is bound to the .init_machine entry of DT_MACHINE_START any harm > in doing this ioremap directly or the DT method would be recommended? I guess that DT is always recommended. I would use something like of_find_compatible_node() + of_iomap() on the syscon device for that (after of_platform_populate()). Probably you could use also directly the physical location or a iotable but it is definitely uglier IMO. -- Carlo Caione _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
