build warnings: multi_v7_defconfig + LPAE, printk with variable types

Kevin Hilman khilman at
Wed Aug 21 11:49:36 EDT 2013

Fabio Estevam <festevam at> writes:

> On Wed, Aug 21, 2013 at 12:15 PM, Kevin Hilman <khilman at> wrote:
>> I've started auto-building the multi_v7_defconfig with LPAE enabled, and
>> noticed a handful of warnings[1]
>> Several are due to using prink format on a type that changes with a
>> config option (e.g several below use %x to print a resource_size_t,
>> which is obviously different between 32- and 64-bit builds.
>> So this got me to wondering if there is "one true way" for using printk
>> on types that might change with config option (preferably without
>> ifdef.)
>> The one that comes to mind would be to just always cast to the larger of
>> the types and use the correspondig format.  For the ones below, it would
>> mean casting to (u64) and using '%llx'.
>> Is there a better way?
> Yes, according to Documentation/printk-formats.txt:

> "Physical addresses:
>     %pa    0x01234567 or 0x0123456789abcdef
>     For printing a phys_addr_t type (and its derivatives, such as
>     resource_size_t) which can vary based on build options, regardless of
>     the width of the CPU data path. Passed by reference."

doh, RTFM.  That one is new since the last time I read it.

> I can send a patch fixing these warnings if you want.

Yes, please.  Thanks!

Please split it up into in to one patch for arch/arm/mach-omap2, one for
drivers/dma/* and one for drivers/spi/* so they can be merged through
the proper maintainers.



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