[Mesa-dev] [PATCH 00/15] i965, mesa, glapi: Build libi965_dri on Android

[Chia-I Wu]

On Fri, Aug 5, 2011 at 12:27 PM, Chad Versace <chad at chad-versace.us> wrote:
> On 08/04/2011 11:25 AM, Chia-I Wu wrote:
>> Hi Chad,
>>
>> On Thu, Aug 4, 2011 at 6:47 PM, Chad Versace <chad at chad-versace.us> wrote:
>>> This is the first step in porting i965 to Android, initially to Gingerbread.
>>> Android is ubiquituous now, and the platform's importance can't be denied. The
>>> Intel drivers really should support it.
>>>
>>> The series first builds libglapi, then libmesa, and then libi965_dri.
>>> lib965_dri doens't work yet; it doesn't even link to libdrm. This is just the
>>> initial work to get it to build.
>>>
>>> I'm aware that this may be controversial, so I've attempted to integrate the
>>> Android makefiles as non-disruptively as possible.
>>>  - The Android makefiles attempt to duplicate as little as possible from the
>>>    existing makefiles. In one case, this dictated that some Makefile code be
>>>    extracted into a shared makefile.
>>>  - I've avoided modifying the existsing makefiles except when absolutely
>>>    necessary. When a modification or cleanup was necessary, I have attempted
>>>    to keep the changes minimal and do them incrementally.
>>>  - The locations of the Android makefiles mirror those of the existing
>>>    makefiles.
>>>
>>> The series does not break the Linux i965 build. I doubt it breaks other
>>> drivers' builds, but I haven't tested it. If you want me to check that it
>>> doesn't break your build, just let me know the autoconf options.
>>>
>>> The series lives on my android-gingerbread-i965 branch. If you'd like to try
>>> the Android build yourself, you should pull from my personal Android manifest
>>> [1], which closely mirrors android-x86, and set `BOARD_USES_I965 := true` in
>>> buildspeck.mk.
>>>
>>> [1] repo init -u git://anongit.freedesktop.git/~chadversary/android.manifeset.git -b gingerbread-i965
>> Thanks for bringing this up and working on it.  Before commenting on
>> the changes to Mesa, I'd like to talk a little bit about the external
>> dependencies.
>>
>> To have a working build of Mesa for the Android Gingerbread source
>> tree, these external changes are needed
>>
>>  1) modify Android's init (pid 1) to create DRI device nodes under /dev
>>  2) make off_t 64-bit so that mmap() a GEM object works
>>  3) figure out how to authenticate a DRM fd
>>  4) add libdrm to Android source tree
>>  5) add drm_gralloc (the DDX driver, sort of) to Android source tree
>>
>> There may be more that I cannot recall now.
>>
>> Of these changes, only 3), 4), and 5) affect how Mesa is built.
>> It is safe to assume 4) and 5) are already there, as we have
>> good relationship with those projects.  But how to solve 3) is still
>> an open question.
>
> Luckily, some key people who can help us with 3 belong to my team: the author of
> Wayland, and the authors of Intel's DRM module, i915.ko. I will probe them when
> we reach that bridge.
>
>> We can either spend several months discussing 3) with the Android team
>> before landing Android support to Mesa.
>
> I have been given a timeframe to complete this, and though I cannot discuss the
> details, several months is unacceptable. The Mesa port needs to be completed
> before yesterday.
>
>> Or we can assume it is
>> solved, land the Android support for Mesa probably over the next few
>> weeks, and initiate the discussion with the Android team with
>> something concrete.  Now that we are at this, my preference is the
>> latter.
>
> Yes. We should take the latter approach.
I forgot to mention that we need to do 1), 2), ..., 5) only when we
target for integrating into the vanilla Android tree.  When we target
for integration with Android-x86, these tasks are either done or
worked around.
>> Back to your changes.  I am fine with landing your version and is
>> willing to help review them, proivided your work won't stop after
>> i915/i965 is supported.  Otherwise, I prefer to prepare my version[1]
>> for upstreaming, which can build all actively maintained drivers
>> including Gallium ones.  It would also be really great you can help,
>> and suppose the list is fine with yet another build system for Mesa.
>>
>> [1] http://cgit.freedesktop.org/~olv/mesa/log/?h=android-gingerbread-7.11
>
> You have done a lot of work on the Mesa port, and I want to acknowledge your
> expertise there. Please don't interpret my submission of this series as a
> dismissal of that work. My intent in submitting my own patches was just to start
> the process of getting Android support upstream, incrementally, in a public,
> code-reviewed forum.
>
> Other drivers, of course, should also be supported. I do not want to place any
> obstacle in way of that goal. At each step of the review process, we should
> check with each other that the approach taken is compatible with both Gallium
> and non-Gallium drivers.
We will be basically doing everything from scratch, in smaller steps.
In that case, I see no reason not to do this based on what is already
there.  I did plan to upstream my changes.  So cleaning it up should
not be a nightmare.

Are there missing commits in your branch?  I tried to build it, but it
is almost no-op because sources are listed in the unused
LOCAL_C_SOURCES instead of LOCAL_SRC_FILES.

> My work won't stop once i965 support is completed. I will continue to maintain
> Android i965 for the forseeable future. I expect that we will be collaborating
> on this for a long time.
>
> --
> Chad Versace
> chad at chad-versace.us
>
>



-- 
olv at LunarG.com