[PATCH 0/6+1] ARM: EXYNOS4: SYSMMU: Improvements on SYSMMU driver

[KyongHo Cho]

On Tue, Jul 5, 2011 at 8:14 PM, Marek Szyprowski
<m.szyprowski at samsung.com> wrote:
> Hello,
>
> On Tuesday, July 05, 2011 1:38 AM KyongHo Cho wrote:
>
>> On Mon, Jul 4, 2011 at 3:47 PM, Marek Szyprowski
>> <m.szyprowski at samsung.com> wrote:
>> > Hello,
>> >
>> > I really don't get why do You persist in creating one monster platform
>> > device with resources for ALL SYSMMU/IOMMU controllers that are available
>> > on Exynos4 CPU. We (SPRC, see Andrzej's SYSMMU patches) already proposed
>> > a clean solution for making the SYSMMU controllers independent of each
>> > other as well as making the main SYSMMU driver simpler and more
>> > independent of the particular Exynos4 platform definition. In Linux
>> > device model if the device/controller exist in the system in more than
>> > one instance, there should by one generic driver for it and a set of
>> > platform definitions for each instance.
>> >
>> Did you find this patch? "[PATCH 3/6] ARM: EXYNOS4: SYSMMU"
>> I Cced you because it includes your suggestion.
>
> Right, I'm really sorry. It looks that I'm too busy and misunderstood your
> patches in a brief look.

No problem with that :)

>> > Here is the link to our SYSMMU updated driver (implementing common
>> > iommu API):
>> > http://www.spinics.net/lists/linux-samsung-soc/msg04508.html
>> > The driver still needs some cleanup, but this has been delayed until
>> > the dma-mapping framework update is finished.
>> >
>> > I also don't get why do you want to keep the completely custom sysmmu
>> > driver and implement iommu API on top of it. Is it really required for
>> > anything? Mainline kernel is not a place for custom APIs if there is
>> > already a common, generic one.
>>
>> I did not exposed any custom API.
>> The global function in the last patch is just for IOMMU API implemenation.
>> The header file in the last patch is not for the device drivers but
>> for the IOMMU API implementation.
>> Actually, they can be merged into one single file.
>> But I just wanted to change the kernel code stepwise.
>
> What about arch/arm/plat-s5p/sysmmu.c ? I didn't notice any commit which
> removes this file. Also both drivers/iommu/exynos4_sysmmu.c and
> drivers/iommu/exynos_iommu.c should be merged together.

It will be removed.
And.. omitting removal of that file is my mistake :(
Since clkdev for Exynos4 is not applied to of Joerg Roedel's iommu git
and drivers/iommu is not created in Samsung SOC git,
it is not simple to apply patch for both.

Thanks for pointing out it and I'll send a patch to remove those files
immediately.

On the other hands, merging those files will be also considered.

Regards,
KyongHo Cho.