Re: [PATCH v4 0/8] asm-generic/io.h overhaul

From: Richard Weinberger
Date: Mon Aug 25 2014 - 08:52:35 EST

Am 25.08.2014 14:27, schrieb Thierry Reding:
> On Mon, Aug 25, 2014 at 01:53:30PM +0200, Richard Weinberger wrote:
>> On Wed, Aug 13, 2014 at 12:28 PM, Thierry Reding
>> <thierry.reding@xxxxxxxxx> wrote:
>>> From: Thierry Reding <treding@xxxxxxxxxx>
>>> Hi,
>>> Here is the fourth version of a series that started out as an attempt to
>>> provide string versions of the read*() and write*() accessors to more
>>> architectures so that drivers can use them portably. The series has
>>> since evolved into a more general cleanup of asm-generic/io.h and the
>>> functions defined therein.
>>> Patch 1 is trivial and removes a redundant redefinition of PCI_IOBASE
>>> from the asm/io.h header on ARC. Patches 2 and 3 remove unnecessary
>>> volatile keywoards from some functions, which is a prerequisite to clean
>>> up some of the functions in subsequent patches.
>>> The xlate_dev_{kmem,mem}_ptr() functions are used to map memory when the
>>> /dev/mem device is accessed. Patches 4 and 5 use more consistent data
>>> types for these functions, which will get a "standard" prototype in the
>>> asm-generic/io.h header in a subsequent patch.
>>> Patch 6 is the bulk of this series. It implements the string variants of
>>> the read*() and write*() accessors and cleans up various other parts of
>>> the asm-generic/io.h header file. Macros are converted to static inline
>>> functions for better type checking. Overriding generic implementations
>>> in architectures is handled more consistently.
>>> Patches 7 and 8, finally, make use of the asm-generic/io.h header on the
>>> 32-bit and 64-bit ARM architectures.
>>> This is compile- and runtime-tested on 32-bit and 64-bit ARM and compile
>>> tested on IA64, Microblaze, s390, SPARC, x86 and Xtensa. For ARC,
>>> Blackfin, Metag, OpenRISC, Score and Unicore32 which also use
>>> asm-generic/io.h I couldn't find or build a cross-compiler that would
>>> run on my system. But by code inspection they shouldn't break with this
>>> patch.
>>> To ensure bisectability I built multi_v7_defconfig on 32-bit ARM and the
>>> defconfig for 64-bit ARM, IA64, Microblaze, s390, SPARC, x86 and Xtensa
>>> after each commit and verified that the series does not introduce any
>>> build errors or warnings.
>>> Provided there are no objections to the patches there's still the matter
>>> of how to merge them. Patch 6 depends on patches 1-5 to avoid warnings
>>> and/or errors during the build. Patches 7 and 8 depend on patch 6. In my
>>> opinion it doesn't make much sense to split them up, so I guess we'll
>>> need a volunteer to take them all into one tree. Ideally that tree would
>>> feed into linux-next so that we can get as much build and test-coverage
>>> as possible during the 3.17 release cycle so that these patches can go
>>> into 3.18.
>>> Arnd, I'm opportunistically sending this To: you in the hopes that you
>>> can take it into your asm-generic tree which seems like the best fit for
>>> this.
>> Do you have a git tree for that?
>> Would be nice for testing UML, it depends also on generic io.
> Yes, it's all here:
> staging/asm-generic-io
> That branch is based on today's linux-next (next-20140825).

Looks good, UML builds and boots fine here.

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