* MPC52xx generic DMA using bestcomm @ 2008-07-07 9:40 Andre Schwarz 2008-07-07 12:47 ` Matt Sealey 0 siblings, 1 reply; 6+ messages in thread From: Andre Schwarz @ 2008-07-07 9:40 UTC (permalink / raw) To: Grant Likely; +Cc: linux-ppc list Grant, do you know if someone's working on a more generic DMA solution using BestComm engine on 5200B ? Maybe somthing that accepts a sg-list with callback ops or completion ? Is it possible right now to accelerate simple memcpy ops ? regards, Andre MATRIX VISION GmbH, Talstraße 16, DE-71570 Oppenweiler - Registergericht: Amtsgericht Stuttgart, HRB 271090 Geschäftsführer: Gerhard Thullner, Werner Armingeon, Uwe Furtner ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: MPC52xx generic DMA using bestcomm 2008-07-07 9:40 MPC52xx generic DMA using bestcomm Andre Schwarz @ 2008-07-07 12:47 ` Matt Sealey 2008-07-07 13:36 ` Grant Likely 2008-07-07 13:39 ` Jon Smirl 0 siblings, 2 replies; 6+ messages in thread From: Matt Sealey @ 2008-07-07 12:47 UTC (permalink / raw) To: Andre Schwarz; +Cc: linux-ppc list Andre Schwarz wrote: > Grant, I know I'm not Grant, but.. > do you know if someone's working on a more generic DMA solution using > BestComm engine on 5200B ? > Maybe somthing that accepts a sg-list with callback ops or completion ? It was suggested once or twice, not least by me. > Is it possible right now to accelerate simple memcpy ops ? From my discussions on the subject with Sylvain, it's possible, you just need to use the GenBD and initiate it manually, however it's probably more overhead than work if the data size is small, and BestComm would do better to copy full 32-bit words at a time, and stay aligned, if you have an odd-sized transfer from a non-32-bit aligned address, then you may have to do some incredible amount of work which makes the actual transfer not worth doing (by the time you set it up, the CPU could have copied it on it's own already, I guess what you DO gain is a kernel preemption point.. the CPU can do other things that are important) I for one, though, whether it speeds stuff up or not, love to see this in action and am very willing to test and benchmark it. I would love to see more users, too, as the network stack is not the only system that can benefit.. On a related note does anyone know of the status or what is going on with Clifford Wolf's dmatransfer API? -- Matt Sealey <matt@genesi-usa.com> Genesi, Manager, Developer Relations ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: MPC52xx generic DMA using bestcomm 2008-07-07 12:47 ` Matt Sealey @ 2008-07-07 13:36 ` Grant Likely 2008-07-07 13:39 ` Jon Smirl 1 sibling, 0 replies; 6+ messages in thread From: Grant Likely @ 2008-07-07 13:36 UTC (permalink / raw) To: Matt Sealey; +Cc: Andre Schwarz, linux-ppc list On Mon, Jul 7, 2008 at 6:47 AM, Matt Sealey <matt@genesi-usa.com> wrote: > > > Andre Schwarz wrote: >> >> Grant, > > I know I'm not Grant, but.. ... I agree 100% with your reply and have nothing additional to add. :-) g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: MPC52xx generic DMA using bestcomm 2008-07-07 12:47 ` Matt Sealey 2008-07-07 13:36 ` Grant Likely @ 2008-07-07 13:39 ` Jon Smirl 2008-07-07 14:18 ` Matt Sealey 1 sibling, 1 reply; 6+ messages in thread From: Jon Smirl @ 2008-07-07 13:39 UTC (permalink / raw) To: Matt Sealey; +Cc: Andre Schwarz, linux-ppc list On 7/7/08, Matt Sealey <matt@genesi-usa.com> wrote: > > > Andre Schwarz wrote: > > > Grant, > > > > I know I'm not Grant, but.. > > > > do you know if someone's working on a more generic DMA solution using > > BestComm engine on 5200B ? > > Maybe somthing that accepts a sg-list with callback ops or completion ? > > > > It was suggested once or twice, not least by me. > > > > Is it possible right now to accelerate simple memcpy ops ? > > > > From my discussions on the subject with Sylvain, it's possible, you just > need to use the GenBD and initiate it manually, however it's probably more > overhead than work if the data size is small, and BestComm would do better > to copy full 32-bit words at a time, and stay aligned, if you have an > odd-sized > transfer from a non-32-bit aligned address, then you may have to do some > incredible amount of work which makes the actual transfer not worth doing > (by the time you set it up, the CPU could have copied it on it's own > already, I guess what you DO gain is a kernel preemption point.. the CPU > can do other things that are important) If you want an Efika specific problem, the audio hardware is capable of simultaneously playing music on the S/PDIF and analog outputs. But to do that the samples have to be alternated as they are fed into the AC97 stream. I think the codec can capture that way too but you didn't put a transceiver on the S/PDIF line. In my test driver you only get AC97 or S/PDIF. Grant and I are both working on i2s drivers, when we get those sorted out it shouldn't be too hard to add ac97 back in. That codec driver I sent you was about 95% complete. > > I for one, though, whether it speeds stuff up or not, love to see this in > action and am very willing to test and benchmark it. I would love to see > more users, too, as the network stack is not the only system that can > benefit.. > > On a related note does anyone know of the status or what is going on with > Clifford Wolf's dmatransfer API? > > -- > Matt Sealey <matt@genesi-usa.com> > Genesi, Manager, Developer Relations > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@ozlabs.org > https://ozlabs.org/mailman/listinfo/linuxppc-dev > -- Jon Smirl jonsmirl@gmail.com ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: MPC52xx generic DMA using bestcomm 2008-07-07 13:39 ` Jon Smirl @ 2008-07-07 14:18 ` Matt Sealey 2008-07-07 14:50 ` Jon Smirl 0 siblings, 1 reply; 6+ messages in thread From: Matt Sealey @ 2008-07-07 14:18 UTC (permalink / raw) To: Jon Smirl; +Cc: Andre Schwarz, linux-ppc list Jon Smirl wrote: > On 7/7/08, Matt Sealey <matt@genesi-usa.com> wrote: >> > to do that the samples have to be alternated as they are fed into the > AC97 stream. I think the codec can capture that way too but you > didn't put a transceiver on the S/PDIF line. OT, but the IDT STAC9766 doesn't support S/PDIF input, only output. > In my test driver you only get AC97 or S/PDIF. Grant and I are both > working on i2s drivers, when we get those sorted out it shouldn't be > too hard to add ac97 back in. That codec driver I sent you was about > 95% complete. Indeed and to be honest I only gave it a short glance before having to do about a thousand other things, but I will take another peek some time this week :) -- Matt Sealey <matt@genesi-usa.com> Genesi, Manager, Developer Relations ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: MPC52xx generic DMA using bestcomm 2008-07-07 14:18 ` Matt Sealey @ 2008-07-07 14:50 ` Jon Smirl 0 siblings, 0 replies; 6+ messages in thread From: Jon Smirl @ 2008-07-07 14:50 UTC (permalink / raw) To: Matt Sealey; +Cc: Andre Schwarz, linux-ppc list On 7/7/08, Matt Sealey <matt@genesi-usa.com> wrote: > > Jon Smirl wrote: > > > On 7/7/08, Matt Sealey <matt@genesi-usa.com> wrote: > > > > > > > > > > to do that the samples have to be alternated as they are fed into the > > AC97 stream. I think the codec can capture that way too but you > > didn't put a transceiver on the S/PDIF line. > > > > OT, but the IDT STAC9766 doesn't support S/PDIF input, only output. > > > > In my test driver you only get AC97 or S/PDIF. Grant and I are both > > working on i2s drivers, when we get those sorted out it shouldn't be > > too hard to add ac97 back in. That codec driver I sent you was about > > 95% complete. > > > > Indeed and to be honest I only gave it a short glance before having to > do about a thousand other things, but I will take another peek some > time this week :) You should junk my PSC and DMA code and switch to the code Grant recently posted. Codec should work as is. My PSC code is for a six month old version of ASOC v2. Grant's PSC driver needs to be split into a DMA library and i2s driver. Then make an AC97 version based on his i2s driver that uses the DMA library. Not hard once he splits the i2s driver. We are getting closer to having full featured audio drivers for the mpc5200 platform. > > -- > Matt Sealey <matt@genesi-usa.com> > Genesi, Manager, Developer Relations > -- Jon Smirl jonsmirl@gmail.com ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2008-07-07 14:50 UTC | newest] Thread overview: 6+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2008-07-07 9:40 MPC52xx generic DMA using bestcomm Andre Schwarz 2008-07-07 12:47 ` Matt Sealey 2008-07-07 13:36 ` Grant Likely 2008-07-07 13:39 ` Jon Smirl 2008-07-07 14:18 ` Matt Sealey 2008-07-07 14:50 ` Jon Smirl
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