Re: [RFC] drm work-in-progress (patch attached)

["Chavdar Ivanov" <ci4ic4%gmail.com@localhost>]

2008/5/29 Chavdar Ivanov <ci4ic4%gmail.com@localhost>:
> 2008/5/28 Blair Sadewitz <blair.sadewitz%gmail.com@localhost>:
>> Hello,
>>
>> Attached is a patch reflecting some of the work I've done on the DRM
>> (the part that works, heh).  Some of the improvements:
>>
>> - Use bus_dma(9) everywhere that's appropriate.
>> - Switch the dma_lock to a reader/writer lock.
>> - Fix out-of-order locking in drm_sg_free().
>>
>> Please ensure that your CVS tree is up-to-date before attempting to
>> apply this patch, as it depends on some commits
>> I made yesterday.
>>
>
> I newbie question - will it test and/or work if drm is modloaded?

With MKMODULES=yes I get:

...
cc1: warnings being treated as errors
/usr/src/sys/dev/drm/drm_bufs.c: In function 'drm_addmap':
/usr/src/sys/dev/drm/drm_bufs.c:165: warning: implicit declaration of
function 'btop'
--- dependall-lkm ---
--- lkminit_exec.d ---
--- dependall-modules ---
*** [drm_bufs.o] Error code 1
1 error

nbmake: stopped in /usr/src/sys/modules/drm
*** [dependall] Error code 2
1 error

nbmake: stopped in /usr/src/sys/modules/drm
*** [dependall-drm] Error code 2

Right now I don't want to do another build without kernel modules, so
I will backout the patch for the next build.

...
>
>> Currently, memory for the _DRM_SHM map type is allocated with
>> bus_dma(9) (previously, the code used malloc(9)).
>> On linux, they just use 'vmalloc'--but this is not anything like
>> "shared memory".  I've tried using uao_create(), but thusfar have only
>> managed to produce page fault traps. ;)
>>
>> Using the latest Mesa from pkgsrc and wip/modular-xorg-server, the
>> improvement by using this patch seems obvious to me: far fewer lockups
>> and a "snappier" feel.  If you're using wip- packages, I also
>> recommend using the latest radeon driver sources; I will commit a
>> package if there
>> is any demand.
>
> Last I had a look, this worked only up to R200-R300; I wonder if R350
> is supported already - while the DRM framework seems to work fine on
> my office Kayak w/s with a Radeon 9800SE, I get:
>
> ...
> (II) RADEON(0): Direct rendering enabled
> (II) RADEON(0): Render acceleration unsupported on Radeon 9500/9700 and newer.
> (II) RADEON(0): Render acceleration disabled
> ...
>
> and Xorg freezes if I run glxgears (no crash, mouse cursor moving, but
> that's it, the only way to get X running again is to reboot, 'vbetool
> post' hard locks (I've reported the same earlier probably).
>
>>
>> Any feedback is welcome, as I'd like to know how this works with
>> various hardware configurations.  If you're using amd64 and you have a
>> non-AGP video card (especially those which use scatter/gather memory),
>> there is a good chance X will fail to initialize the DRM with either
>> "can't map ring" or some error related to locking or getting the
>> context SAREA.  This is because the DRM code uses 'unsigned long' as
>> its
>> offset type--which is part of the API.  Until this is fixed, one can
>> work around this insanity by changing the type of the second argument
>> to
>> udv_attach (in sys/uvm/uvm_device.[ch]) from 'voff_t' to 'vsize_t'.
>> Yes, this is an utterly awful hack.
>
> I've been confining myself mostly to i386 so far; amd64 looks much
> better now in comparison to a few years ago,
> so I might start regular builds of that as well; the trouble is the
> decent machines I could put it on are transient,
>
>>
>> Regards,
>>
>> --Blair
>>
>
>
>
> --
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> Chavdar Ivanov | Talbot Way, Small Heath Business Park
> Delcam UK | Birmingham B10 0HJ, United Kingdom
> Customer Support | (+44)121-6831014
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>



-- 
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/dev/random says:
        I always lie. In fact, I'm lying to you right now!
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Chavdar Ivanov | Talbot Way, Small Heath Business Park
Delcam UK | Birmingham B10 0HJ, United Kingdom
Customer Support | (+44)121-6831014
----------------------------------------------------------------