* [PATCH 0/3] Support burst request by peripherals @ 2016-08-05 2:53 Shawn Lin [not found] ` <1470365602-32586-1-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 0 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-05 2:53 UTC (permalink / raw) To: Vinod Koul Cc: Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, Shawn Lin Burst request is supported by pl330 but the original code only support single mode as some Socs didn't implement it. So this feature has been missing for a long time. But it's very important for efficiency. This patchset is gonna support it without the probability of breaking old(other) platforms, so the new optional property is introduced. Also when supporting burst request type, we could be able to deal with unaligned case internally. After applying this patchset, we could see significant improvement when doing mem-2-dev/dev-2-mem/mem-2-mem which I mentioned in the commit msg. I would appreciate it if folks could help review and test it.:) Thanks for any feedback. Shawn Lin (3): dt/bindings: arm-pl330: add description of arm,pl330-periph-burst dmaengine: pl330: enable burst mode by parsing dt dmaengine: pl330: support transfer unaligned with (burst len * burst size) .../devicetree/bindings/dma/arm-pl330.txt | 1 + drivers/dma/pl330.c | 58 +++++++++++++++------- 2 files changed, 42 insertions(+), 17 deletions(-) -- 2.3.7 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
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* [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst [not found] ` <1470365602-32586-1-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> @ 2016-08-05 2:53 ` Shawn Lin 2016-08-05 3:34 ` Vinod Koul 2016-08-05 2:53 ` [PATCH 2/3] dmaengine: pl330: enable burst mode by parsing dt Shawn Lin 2016-08-05 2:53 ` [PATCH 3/3] dmaengine: pl330: support transfer unaligned with (burst len * burst size) Shawn Lin 2 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-05 2:53 UTC (permalink / raw) To: Vinod Koul Cc: Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, Shawn Lin This patch adds the "arm,pl330-periph-burst" for arm-pl330 to support busrt mode. Signed-off-by: Shawn Lin <shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> --- Documentation/devicetree/bindings/dma/arm-pl330.txt | 1 + 1 file changed, 1 insertion(+) diff --git a/Documentation/devicetree/bindings/dma/arm-pl330.txt b/Documentation/devicetree/bindings/dma/arm-pl330.txt index db7e226..262e97a 100644 --- a/Documentation/devicetree/bindings/dma/arm-pl330.txt +++ b/Documentation/devicetree/bindings/dma/arm-pl330.txt @@ -16,6 +16,7 @@ Optional properties: - dma-channels: contains the total number of DMA channels supported by the DMAC - dma-requests: contains the total number of DMA requests supported by the DMAC - arm,pl330-broken-no-flushp: quirk for avoiding to execute DMAFLUSHP + - arm,pl330-periph-burst: set peripheral dma request type as burst mode Example: -- 2.3.7 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply related [flat|nested] 14+ messages in thread
* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst 2016-08-05 2:53 ` [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst Shawn Lin @ 2016-08-05 3:34 ` Vinod Koul 2016-08-05 7:25 ` Shawn Lin 0 siblings, 1 reply; 14+ messages in thread From: Vinod Koul @ 2016-08-05 3:34 UTC (permalink / raw) To: Shawn Lin Cc: Rob Herring, Huibin Hong, Xing Zheng, devicetree, dianders, briannorris, Caesar Wang, dmaengine, linux-kernel, linux-arm-kernel, linux-rockchip On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: > This patch adds the "arm,pl330-periph-burst" for arm-pl330 to > support busrt mode. why should this be DT property. Only reason I can think of if some hw versions support this and some won't. If all are supporting, please enable it everywhere for obvious reasons. -- ~Vinod ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst 2016-08-05 3:34 ` Vinod Koul @ 2016-08-05 7:25 ` Shawn Lin [not found] ` <ea3572fa-4bff-87db-d5ad-f406809f8296-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 0 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-05 7:25 UTC (permalink / raw) To: Vinod Koul Cc: shawn.lin, Rob Herring, Huibin Hong, Xing Zheng, devicetree, dianders, briannorris, Caesar Wang, dmaengine, linux-kernel, linux-arm-kernel, linux-rockchip Hi Vinod, 在 2016/8/5 11:34, Vinod Koul 写道: > On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: >> This patch adds the "arm,pl330-periph-burst" for arm-pl330 to >> support busrt mode. > > why should this be DT property. Only reason I can think of if some hw > versions support this and some won't. yes, if we want to support burst mode, both of the master(pl330) and client(several peripherals) should implement it, otherwise it will be broken when enabling. So I mentioned it on my cover letter as the reason to introduce this optional property. If people add this property and find it's ok for their platform, they could land new dt-patch to add it. But we could *not* presume that we could get all users involved in testing this patchet. I don't wanna to break any other platforms, so it's needed. Thanks. > > If all are supporting, please enable it everywhere for obvious reasons. > -- Best Regards Shawn Lin ^ permalink raw reply [flat|nested] 14+ messages in thread
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* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst [not found] ` <ea3572fa-4bff-87db-d5ad-f406809f8296-TNX95d0MmH7DzftRWevZcw@public.gmane.org> @ 2016-08-09 8:39 ` Lars-Peter Clausen 2016-08-09 9:12 ` Shawn Lin 0 siblings, 1 reply; 14+ messages in thread From: Lars-Peter Clausen @ 2016-08-09 8:39 UTC (permalink / raw) To: Shawn Lin, Vinod Koul Cc: Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r On 08/05/2016 09:25 AM, Shawn Lin wrote: > Hi Vinod, > > 在 2016/8/5 11:34, Vinod Koul 写道: >> On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: >>> This patch adds the "arm,pl330-periph-burst" for arm-pl330 to >>> support busrt mode. >> >> why should this be DT property. Only reason I can think of if some hw >> versions support this and some won't. > > yes, if we want to support burst mode, both of the master(pl330) and > client(several peripherals) should implement it, otherwise it will > be broken when enabling. As you said, it is up to the consumer peripheral whether it supports BURST, SINGLE or both. So this is a per client property, but you specify this as a a global property on the producer side. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst 2016-08-09 8:39 ` Lars-Peter Clausen @ 2016-08-09 9:12 ` Shawn Lin [not found] ` <1d42542f-c43c-5c4b-01b7-ba0ca085004a-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 0 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-09 9:12 UTC (permalink / raw) To: Lars-Peter Clausen, Vinod Koul Cc: shawn.lin, Rob Herring, Huibin Hong, Xing Zheng, devicetree, dianders, briannorris, Caesar Wang, dmaengine, linux-kernel, linux-arm-kernel, linux-rockchip Hi Lars-Peter, 在 2016/8/9 16:39, Lars-Peter Clausen 写道: > On 08/05/2016 09:25 AM, Shawn Lin wrote: >> Hi Vinod, >> >> 在 2016/8/5 11:34, Vinod Koul 写道: >>> On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: >>>> This patch adds the "arm,pl330-periph-burst" for arm-pl330 to >>>> support busrt mode. >>> >>> why should this be DT property. Only reason I can think of if some hw >>> versions support this and some won't. >> >> yes, if we want to support burst mode, both of the master(pl330) and >> client(several peripherals) should implement it, otherwise it will >> be broken when enabling. > > As you said, it is up to the consumer peripheral whether it supports BURST, > SINGLE or both. So this is a per client property, but you specify this as a > a global property on the producer side. Thanks for comment. yup, but what is the proper way to add it ? :) a) If pl330 support BURST as well as all the peripherals, we could enable it. b) If pl300 support BURST, but all the peripherals don't support it, we could not enable it. c) If pl300 support BURST, but not all the peripherals support it, we also could not enable it. the burst feature of peripheral IP may be vendor-specific, but the common driver for this peripheral are used for many many vendors which means we could not check all of this info. It's very likely to break them... I couldn't figure out how many upstreamed peripheral drivers who are using pl300 either. So this check should be done by all this vendors but we could make sure we don't break them before they check a), b), c), right? > > > > -- Best Regards Shawn Lin ^ permalink raw reply [flat|nested] 14+ messages in thread
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* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst [not found] ` <1d42542f-c43c-5c4b-01b7-ba0ca085004a-TNX95d0MmH7DzftRWevZcw@public.gmane.org> @ 2016-08-17 8:11 ` Shawn Lin 2016-08-19 2:45 ` Vinod Koul 0 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-17 8:11 UTC (permalink / raw) To: Lars-Peter Clausen, Vinod Koul Cc: shawn.lin-TNX95d0MmH7DzftRWevZcw, Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r Hi, Vinod and Lars-Peter Ping.. Any better idea to share :) On 2016/8/9 17:12, Shawn Lin wrote: > Hi Lars-Peter, > > 在 2016/8/9 16:39, Lars-Peter Clausen 写道: >> On 08/05/2016 09:25 AM, Shawn Lin wrote: >>> Hi Vinod, >>> >>> 在 2016/8/5 11:34, Vinod Koul 写道: >>>> On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: >>>>> This patch adds the "arm,pl330-periph-burst" for arm-pl330 to >>>>> support busrt mode. >>>> >>>> why should this be DT property. Only reason I can think of if some hw >>>> versions support this and some won't. >>> >>> yes, if we want to support burst mode, both of the master(pl330) and >>> client(several peripherals) should implement it, otherwise it will >>> be broken when enabling. >> >> As you said, it is up to the consumer peripheral whether it supports >> BURST, >> SINGLE or both. So this is a per client property, but you specify this >> as a >> a global property on the producer side. > > Thanks for comment. > > yup, but what is the proper way to add it ? :) > > > a) If pl330 support BURST as well as all the peripherals, we could > enable it. > > b) If pl300 support BURST, but all the peripherals don't support it, > we could not enable it. > > c) If pl300 support BURST, but not all the peripherals support it, > we also could not enable it. > > the burst feature of peripheral IP may be vendor-specific, but the > common driver for this peripheral are used for many many vendors which > means we could not check all of this info. It's very likely to break > them... I couldn't figure out how many upstreamed peripheral drivers > who are using pl300 either. > > So this check should be done by all this vendors but we could make > sure we don't break them before they check a), b), c), right? > > >> >> >> >> > > -- Best Regards Shawn Lin -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst 2016-08-17 8:11 ` Shawn Lin @ 2016-08-19 2:45 ` Vinod Koul 2016-08-21 1:00 ` Shawn Lin 0 siblings, 1 reply; 14+ messages in thread From: Vinod Koul @ 2016-08-19 2:45 UTC (permalink / raw) To: Shawn Lin Cc: Lars-Peter Clausen, Rob Herring, Huibin Hong, Xing Zheng, devicetree, dianders, briannorris, Caesar Wang, dmaengine, linux-kernel, linux-arm-kernel, linux-rockchip On Wed, Aug 17, 2016 at 04:11:03PM +0800, Shawn Lin wrote: > Hi, Vinod and Lars-Peter > > Ping.. Any better idea to share :) > > On 2016/8/9 17:12, Shawn Lin wrote: > >Hi Lars-Peter, > > > >在 2016/8/9 16:39, Lars-Peter Clausen 写道: > >>On 08/05/2016 09:25 AM, Shawn Lin wrote: > >>>Hi Vinod, > >>> > >>>在 2016/8/5 11:34, Vinod Koul 写道: > >>>>On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: > >>>>>This patch adds the "arm,pl330-periph-burst" for arm-pl330 to > >>>>>support busrt mode. > >>>> > >>>>why should this be DT property. Only reason I can think of if some hw > >>>>versions support this and some won't. > >>> > >>>yes, if we want to support burst mode, both of the master(pl330) and > >>>client(several peripherals) should implement it, otherwise it will > >>>be broken when enabling. > >> > >>As you said, it is up to the consumer peripheral whether it supports > >>BURST, > >>SINGLE or both. So this is a per client property, but you specify this > >>as a > >>a global property on the producer side. > > > >Thanks for comment. > > > >yup, but what is the proper way to add it ? :) > > > > > >a) If pl330 support BURST as well as all the peripherals, we could > >enable it. > > > >b) If pl300 support BURST, but all the peripherals don't support it, > >we could not enable it. > > > >c) If pl300 support BURST, but not all the peripherals support it, > >we also could not enable it. > > > >the burst feature of peripheral IP may be vendor-specific, but the > >common driver for this peripheral are used for many many vendors which > >means we could not check all of this info. It's very likely to break > >them... I couldn't figure out how many upstreamed peripheral drivers > >who are using pl300 either. > > > >So this check should be done by all this vendors but we could make > >sure we don't break them before they check a), b), c), right? Since support for BURST needs to be from peripheral too, we should have that as a property for peripheral not for controller. The peripheral drivers can communicate the burst to be used to pl330 using src_maxburst/dst_maxburst in dma_slave_config. We can use this value to indicate the DMA should be single (a value of 0) or burst with "burst" value. -- ~Vinod ^ permalink raw reply [flat|nested] 14+ messages in thread
* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst 2016-08-19 2:45 ` Vinod Koul @ 2016-08-21 1:00 ` Shawn Lin [not found] ` <d4574737-f7b7-2726-373c-31cc81274a32-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 0 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-21 1:00 UTC (permalink / raw) To: Vinod Koul Cc: shawn.lin-TNX95d0MmH7DzftRWevZcw, Lars-Peter Clausen, Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r Hi Vinod, 在 2016/8/19 10:45, Vinod Koul 写道: > On Wed, Aug 17, 2016 at 04:11:03PM +0800, Shawn Lin wrote: >> Hi, Vinod and Lars-Peter >> >> Ping.. Any better idea to share :) >> >> On 2016/8/9 17:12, Shawn Lin wrote: >>> Hi Lars-Peter, >>> >>> 在 2016/8/9 16:39, Lars-Peter Clausen 写道: >>>> On 08/05/2016 09:25 AM, Shawn Lin wrote: >>>>> Hi Vinod, >>>>> >>>>> 在 2016/8/5 11:34, Vinod Koul 写道: >>>>>> On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: >>>>>>> This patch adds the "arm,pl330-periph-burst" for arm-pl330 to >>>>>>> support busrt mode. >>>>>> >>>>>> why should this be DT property. Only reason I can think of if some hw >>>>>> versions support this and some won't. >>>>> >>>>> yes, if we want to support burst mode, both of the master(pl330) and >>>>> client(several peripherals) should implement it, otherwise it will >>>>> be broken when enabling. >>>> >>>> As you said, it is up to the consumer peripheral whether it supports >>>> BURST, >>>> SINGLE or both. So this is a per client property, but you specify this >>>> as a >>>> a global property on the producer side. >>> >>> Thanks for comment. >>> >>> yup, but what is the proper way to add it ? :) >>> >>> >>> a) If pl330 support BURST as well as all the peripherals, we could >>> enable it. >>> >>> b) If pl300 support BURST, but all the peripherals don't support it, >>> we could not enable it. >>> >>> c) If pl300 support BURST, but not all the peripherals support it, >>> we also could not enable it. >>> >>> the burst feature of peripheral IP may be vendor-specific, but the >>> common driver for this peripheral are used for many many vendors which >>> means we could not check all of this info. It's very likely to break >>> them... I couldn't figure out how many upstreamed peripheral drivers >>> who are using pl300 either. >>> >>> So this check should be done by all this vendors but we could make >>> sure we don't break them before they check a), b), c), right? > > Since support for BURST needs to be from peripheral too, we should have > that as a property for peripheral not for controller. > > The peripheral drivers can communicate the burst to be used to pl330 > using src_maxburst/dst_maxburst in dma_slave_config. We can use this > value to indicate the DMA should be single (a value of 0) or burst with > "burst" value. Thanks for sharing this. But this is really a difficult trade-off decision to add this new property for pl330 only. Burst mode was supported by Boojin Kim's patch by default(commit 848e9776fee42 ("dmaengine: pl330: support burst mode for dev-to-mem and mem-to-dev transmit")). But we found it will break SoCFPGA or Exynos4412 reported by Dinh Nguyen and Bartlomiej Zolnierkiewicz[0]. So finally Caesar Wang contributed a patch, commit 0a18f9b268 (" dmaengine: pl330: fix to support the burst mode") to fix it, but what it actually did is to use single burst for any case, namely some kind of regression for Boojin Kim's improvement. So we can see these drivers which was broken by enabling burst mode had already set src_maxburst/dst_maxburst. It looks to me so unfortunate that the driver like 8250_dw.c was using so widely that we couldn't set scr/dst_maxburst as this is really vendor specific for whether it supports burst for 8250_dw or not.. So it is quite painful that we probably will get dozens of regression reports when enabling burst mode by default. But without this, we have been suffering from low performance quite a long time due to this roadblock. Two possible paths to land this patch are: (1) Keep this property for pl330 only, so we have no chance to break others and we could make the platforms enjoy it if adding this property for their own dts. (2) Figuer out all the broken platfroms if enabling burst and fix them one by one for the src/dst_maxburst(maybe by enabling burst mode and get regression reports). If we could not solve any one of them, then we have to give up all the effort we do, and let this pain keep on stalling people's expectation of better performance. I would appreciate it if you could share your thought more, as I really want more platforms benefit from it(at least don't break them) :) [0] http://www.gossamer-threads.com/lists/linux/kernel/2374171 > -- Best Regards Shawn Lin -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
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* Re: [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst [not found] ` <d4574737-f7b7-2726-373c-31cc81274a32-TNX95d0MmH7DzftRWevZcw@public.gmane.org> @ 2016-08-22 6:04 ` Vinod Koul 0 siblings, 0 replies; 14+ messages in thread From: Vinod Koul @ 2016-08-22 6:04 UTC (permalink / raw) To: Shawn Lin Cc: Lars-Peter Clausen, Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r On Sun, Aug 21, 2016 at 09:00:58AM +0800, Shawn Lin wrote: > Hi Vinod, > > 在 2016/8/19 10:45, Vinod Koul 写道: > >On Wed, Aug 17, 2016 at 04:11:03PM +0800, Shawn Lin wrote: > >>Hi, Vinod and Lars-Peter > >> > >>Ping.. Any better idea to share :) > >> > >>On 2016/8/9 17:12, Shawn Lin wrote: > >>>Hi Lars-Peter, > >>> > >>>在 2016/8/9 16:39, Lars-Peter Clausen 写道: > >>>>On 08/05/2016 09:25 AM, Shawn Lin wrote: > >>>>>Hi Vinod, > >>>>> > >>>>>在 2016/8/5 11:34, Vinod Koul 写道: > >>>>>>On Fri, Aug 05, 2016 at 10:53:20AM +0800, Shawn Lin wrote: > >>>>>>>This patch adds the "arm,pl330-periph-burst" for arm-pl330 to > >>>>>>>support busrt mode. > >>>>>> > >>>>>>why should this be DT property. Only reason I can think of if some hw > >>>>>>versions support this and some won't. > >>>>> > >>>>>yes, if we want to support burst mode, both of the master(pl330) and > >>>>>client(several peripherals) should implement it, otherwise it will > >>>>>be broken when enabling. > >>>> > >>>>As you said, it is up to the consumer peripheral whether it supports > >>>>BURST, > >>>>SINGLE or both. So this is a per client property, but you specify this > >>>>as a > >>>>a global property on the producer side. > >>> > >>>Thanks for comment. > >>> > >>>yup, but what is the proper way to add it ? :) > >>> > >>> > >>>a) If pl330 support BURST as well as all the peripherals, we could > >>>enable it. > >>> > >>>b) If pl300 support BURST, but all the peripherals don't support it, > >>>we could not enable it. > >>> > >>>c) If pl300 support BURST, but not all the peripherals support it, > >>>we also could not enable it. > >>> > >>>the burst feature of peripheral IP may be vendor-specific, but the > >>>common driver for this peripheral are used for many many vendors which > >>>means we could not check all of this info. It's very likely to break > >>>them... I couldn't figure out how many upstreamed peripheral drivers > >>>who are using pl300 either. > >>> > >>>So this check should be done by all this vendors but we could make > >>>sure we don't break them before they check a), b), c), right? > > > >Since support for BURST needs to be from peripheral too, we should have > >that as a property for peripheral not for controller. > > > >The peripheral drivers can communicate the burst to be used to pl330 > >using src_maxburst/dst_maxburst in dma_slave_config. We can use this > >value to indicate the DMA should be single (a value of 0) or burst with > >"burst" value. > > Thanks for sharing this. > > But this is really a difficult trade-off decision to add this new > property for pl330 only. > > Burst mode was supported by Boojin Kim's patch by default(commit > 848e9776fee42 ("dmaengine: pl330: support burst mode for dev-to-mem and > mem-to-dev transmit")). But we found it will break SoCFPGA or > Exynos4412 reported by Dinh Nguyen and Bartlomiej Zolnierkiewicz[0]. > So finally Caesar Wang contributed a patch, commit 0a18f9b268 (" > dmaengine: pl330: fix to support the burst mode") to fix it, but what > it actually did is to use single burst for any case, namely some kind > of regression for Boojin Kim's improvement. > > So we can see these drivers which was broken by enabling burst mode > had already set src_maxburst/dst_maxburst. It looks to me so unfortunate > that the driver like 8250_dw.c was using so widely that we couldn't > set scr/dst_maxburst as this is really vendor specific for whether it > supports burst for 8250_dw or not.. > > So it is quite painful that we probably will get dozens of regression > reports when enabling burst mode by default. But without this, we have > been suffering from low performance quite a long time due to this > roadblock. well in that case I would suggest fixing client first. Make all users of pl330 not to use burst mode and then enable them one by one after testing > > Two possible paths to land this patch are: > (1) Keep this property for pl330 only, so we have no chance to > break others and we could make the platforms enjoy it if adding this > property for their own dts. > > (2) Figuer out all the broken platfroms if enabling burst and fix them > one by one for the src/dst_maxburst(maybe by enabling burst mode and > get regression reports). If we could not solve any one of them, then we > have to give up all the effort we do, and let this pain keep on > stalling people's expectation of better performance. > > > I would appreciate it if you could share your thought more, as I > really want more platforms benefit from it(at least don't break > them) :) > > > [0] http://www.gossamer-threads.com/lists/linux/kernel/2374171 > > > > > > -- > Best Regards > Shawn Lin > -- ~Vinod -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 2/3] dmaengine: pl330: enable burst mode by parsing dt [not found] ` <1470365602-32586-1-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-05 2:53 ` [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst Shawn Lin @ 2016-08-05 2:53 ` Shawn Lin 2016-08-07 9:20 ` Xing Zheng 2016-08-05 2:53 ` [PATCH 3/3] dmaengine: pl330: support transfer unaligned with (burst len * burst size) Shawn Lin 2 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-05 2:53 UTC (permalink / raw) To: Vinod Koul Cc: Rob Herring, Huibin Hong, Xing Zheng, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, Shawn Lin Currently pl330 use single mode defaultly. But burst mode can improve efficiency of memory accessing. We couldn't enable it by defalut in case of breaking any Socs which don't support it. With burst mode supported, we could see the improvement significantly when tesing SPI transfer etc. default single mode [ 88.292550] spi write 65536*1 cost 32402us speed:2022KB/S After applied with burst mode(len 16) [ 17.625296] spi write 65536*1 cost 17830us speed:3675KB/S Cc: Huibin Hong <huibin.hong-TNX95d0MmH7DzftRWevZcw@public.gmane.org> Cc: Xing Zheng <zhengxing-TNX95d0MmH7DzftRWevZcw@public.gmane.org> Signed-off-by: Shawn Lin <shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> --- drivers/dma/pl330.c | 35 +++++++++++++++++++++-------------- 1 file changed, 21 insertions(+), 14 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 4fc3ffb..a09bf22 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -491,6 +491,8 @@ struct pl330_dmac { /* Peripheral channels connected to this DMAC */ unsigned int num_peripherals; struct dma_pl330_chan *peripherals; /* keep at end */ + /* set peripherals request type according to soc config */ + enum pl330_cond peripherals_req_type; int quirks; }; @@ -1156,12 +1158,7 @@ static inline int _ldst_devtomem(struct pl330_dmac *pl330, unsigned dry_run, int cyc) { int off = 0; - enum pl330_cond cond; - - if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) - cond = BURST; - else - cond = SINGLE; + enum pl330_cond cond = pl330->peripherals_req_type; while (cyc--) { off += _emit_WFP(dry_run, &buf[off], cond, pxs->desc->peri); @@ -1181,12 +1178,7 @@ static inline int _ldst_memtodev(struct pl330_dmac *pl330, const struct _xfer_spec *pxs, int cyc) { int off = 0; - enum pl330_cond cond; - - if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) - cond = BURST; - else - cond = SINGLE; + enum pl330_cond cond = pl330->peripherals_req_type; while (cyc--) { off += _emit_WFP(dry_run, &buf[off], cond, pxs->desc->peri); @@ -2597,7 +2589,12 @@ static struct dma_async_tx_descriptor *pl330_prep_dma_cyclic( desc->rqtype = direction; desc->rqcfg.brst_size = pch->burst_sz; - desc->rqcfg.brst_len = 1; + + if (pl330->peripherals_req_type == BURST) + desc->rqcfg.brst_len = pch->burst_len; + else + desc->rqcfg.brst_len = 1; + desc->bytes_requested = period_len; fill_px(&desc->px, dst, src, period_len); @@ -2742,7 +2739,12 @@ pl330_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, } desc->rqcfg.brst_size = pch->burst_sz; - desc->rqcfg.brst_len = 1; + + if (pch->dmac->peripherals_req_type == BURST) + desc->rqcfg.brst_len = pch->burst_len; + else + desc->rqcfg.brst_len = 1; + desc->rqtype = direction; desc->bytes_requested = sg_dma_len(sg); } @@ -2836,6 +2838,11 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) pl330->mcbufsz = pdat ? pdat->mcbuf_sz : 0; + if (of_find_property(np, "arm,pl330-periph-burst", NULL)) + pl330->peripherals_req_type = BURST; + else + pl330->peripherals_req_type = SINGLE; + /* get quirk */ for (i = 0; i < ARRAY_SIZE(of_quirks); i++) if (of_property_read_bool(np, of_quirks[i].quirk)) -- 2.3.7 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply related [flat|nested] 14+ messages in thread
* Re: [PATCH 2/3] dmaengine: pl330: enable burst mode by parsing dt 2016-08-05 2:53 ` [PATCH 2/3] dmaengine: pl330: enable burst mode by parsing dt Shawn Lin @ 2016-08-07 9:20 ` Xing Zheng 0 siblings, 0 replies; 14+ messages in thread From: Xing Zheng @ 2016-08-07 9:20 UTC (permalink / raw) To: Shawn Lin, Vinod Koul Cc: Rob Herring, Huibin Hong, devicetree, dianders, briannorris, Caesar Wang, dmaengine, linux-kernel, linux-arm-kernel, linux-rockchip Hi Shawn, On 2016年08月05日 10:53, Shawn Lin wrote: > Currently pl330 use single mode defaultly. But burst > mode can improve efficiency of memory accessing. We > couldn't enable it by defalut in case of breaking any > Socs which don't support it. > > With burst mode supported, we could see the improvement > significantly when tesing SPI transfer etc. > > default single mode > [ 88.292550] spi write 65536*1 cost 32402us speed:2022KB/S > > After applied with burst mode(len 16) > [ 17.625296] spi write 65536*1 cost 17830us speed:3675KB/S > > Cc: Huibin Hong <huibin.hong@rock-chips.com> > Cc: Xing Zheng <zhengxing@rock-chips.com> > Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> > --- > Tested-by: Xing Zheng <zhengxing@rock-chips.com> Thanks -- - Xing Zheng ^ permalink raw reply [flat|nested] 14+ messages in thread
* [PATCH 3/3] dmaengine: pl330: support transfer unaligned with (burst len * burst size) [not found] ` <1470365602-32586-1-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-05 2:53 ` [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst Shawn Lin 2016-08-05 2:53 ` [PATCH 2/3] dmaengine: pl330: enable burst mode by parsing dt Shawn Lin @ 2016-08-05 2:53 ` Shawn Lin [not found] ` <1470365602-32586-4-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2 siblings, 1 reply; 14+ messages in thread From: Shawn Lin @ 2016-08-05 2:53 UTC (permalink / raw) To: Vinod Koul Cc: devicetree-u79uwXL29TY76Z2rM5mHXA, Xing Zheng, Huibin Hong, Shawn Lin, briannorris-F7+t8E8rja9g9hUCZPvPmw, dianders-F7+t8E8rja9g9hUCZPvPmw, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, Rob Herring, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, Caesar Wang Currently pl330 doesn't support transfer which doesn't align with burst len * burst size. This should be only for single mode. Let's allow it for busrt mode if available. e.g. transfers 0x10002 bytes: First loop 256*16*16=0x10000, burst size is 1, burst length is 16. Then the second loop 2 bytes, burst size is 1, burst length is 1. f0041000: DMAMOV CCR 0xbc02f1 f0041006: DMAMOV SAR 0xdd6c0000 f004100c: DMAMOV DAR 0xff1d0400 f0041012: DMALP_0 15 f0041014: DMALP_1 255 f0041016: DMAWFPB 12 f0041018: DMALDA f0041019: DMASTPB 12 f004101b: DMAFLUSHP 12 f004101d: DMALPENDA_1 bjmpto_7 f004101f: DMALPENDA_0 bjmpto_b f0041021: DMAMOV CCR 0x800201 f0041027: DMALP_1 1 f0041029: DMAWFPB 12 f004102b: DMALDA f004102c: DMASTPB 12 f004102e: DMAFLUSHP 12 f0041030: DMALPENDA_1 bjmpto_7 f0041032: DMASEV 0 f0041034: DMAEND Signed-off-by: Shawn Lin <shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> --- drivers/dma/pl330.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index a09bf22..cdb4afc 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -240,6 +240,7 @@ enum pl330_byteswap { #define BYTE_TO_BURST(b, ccr) ((b) / BRST_SIZE(ccr) / BRST_LEN(ccr)) #define BURST_TO_BYTE(c, ccr) ((c) * BRST_SIZE(ccr) * BRST_LEN(ccr)) +#define BYTE_MOD_BURST_LEN(b, ccr) (((b) / BRST_SIZE(ccr)) % BRST_LEN(ccr)) /* * With 256 bytes, we can do more than 2.5MB and 5MB xfers per req @@ -1331,6 +1332,19 @@ static inline int _setup_xfer(struct pl330_dmac *pl330, /* Setup Loop(s) */ off += _setup_loops(pl330, dry_run, &buf[off], pxs); + if (pl330->peripherals_req_type == BURST) { + unsigned int ccr = pxs->ccr; + unsigned long c = 0; + + c = BYTE_MOD_BURST_LEN(x->bytes, pxs->ccr); + if (c) { + ccr &= ~(0xf << CC_SRCBRSTLEN_SHFT); + ccr &= ~(0xf << CC_DSTBRSTLEN_SHFT); + off += _emit_MOV(dry_run, &buf[off], CCR, ccr); + off += _loop(pl330, dry_run, &buf[off], &c, pxs); + } + } + return off; } @@ -1353,9 +1367,12 @@ static int _setup_req(struct pl330_dmac *pl330, unsigned dry_run, off += _emit_MOV(dry_run, &buf[off], CCR, pxs->ccr); x = &pxs->desc->px; - /* Error if xfer length is not aligned at burst size */ - if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr))) - return -EINVAL; + + if (pl330->peripherals_req_type != BURST) { + /* Error if xfer length is not aligned at burst size */ + if (x->bytes % (BRST_SIZE(pxs->ccr) * BRST_LEN(pxs->ccr))) + return -EINVAL; + } off += _setup_xfer(pl330, dry_run, &buf[off], pxs); -- 2.3.7 ^ permalink raw reply related [flat|nested] 14+ messages in thread
[parent not found: <1470365602-32586-4-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org>]
* Re: [PATCH 3/3] dmaengine: pl330: support transfer unaligned with (burst len * burst size) [not found] ` <1470365602-32586-4-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> @ 2016-08-07 9:21 ` Xing Zheng 0 siblings, 0 replies; 14+ messages in thread From: Xing Zheng @ 2016-08-07 9:21 UTC (permalink / raw) To: Shawn Lin, Vinod Koul Cc: Rob Herring, Huibin Hong, devicetree-u79uwXL29TY76Z2rM5mHXA, dianders-F7+t8E8rja9g9hUCZPvPmw, briannorris-F7+t8E8rja9g9hUCZPvPmw, Caesar Wang, dmaengine-u79uwXL29TY76Z2rM5mHXA, linux-kernel-u79uwXL29TY76Z2rM5mHXA, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r Hi Shawn On 2016年08月05日 10:53, Shawn Lin wrote: > Currently pl330 doesn't support transfer which doesn't > align with burst len * burst size. This should be only > for single mode. Let's allow it for busrt mode if available. > > e.g. transfers 0x10002 bytes: > First loop 256*16*16=0x10000, burst size is 1, burst length is 16. > Then the second loop 2 bytes, burst size is 1, burst length is 1. > > f0041000: DMAMOV CCR 0xbc02f1 > f0041006: DMAMOV SAR 0xdd6c0000 > f004100c: DMAMOV DAR 0xff1d0400 > f0041012: DMALP_0 15 > f0041014: DMALP_1 255 > f0041016: DMAWFPB 12 > f0041018: DMALDA > f0041019: DMASTPB 12 > f004101b: DMAFLUSHP 12 > f004101d: DMALPENDA_1 bjmpto_7 > f004101f: DMALPENDA_0 bjmpto_b > f0041021: DMAMOV CCR 0x800201 > f0041027: DMALP_1 1 > f0041029: DMAWFPB 12 > f004102b: DMALDA > f004102c: DMASTPB 12 > f004102e: DMAFLUSHP 12 > f0041030: DMALPENDA_1 bjmpto_7 > f0041032: DMASEV 0 > f0041034: DMAEND > > Signed-off-by: Shawn Lin <shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> > Tested-by: Xing Zheng <zhengxing-TNX95d0MmH7DzftRWevZcw@public.gmane.org> Thanks. -- - Xing Zheng -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html ^ permalink raw reply [flat|nested] 14+ messages in thread
end of thread, other threads:[~2016-08-22 6:04 UTC | newest] Thread overview: 14+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2016-08-05 2:53 [PATCH 0/3] Support burst request by peripherals Shawn Lin [not found] ` <1470365602-32586-1-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-05 2:53 ` [PATCH 1/3] dt/bindings: arm-pl330: add description of arm,pl330-periph-burst Shawn Lin 2016-08-05 3:34 ` Vinod Koul 2016-08-05 7:25 ` Shawn Lin [not found] ` <ea3572fa-4bff-87db-d5ad-f406809f8296-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-09 8:39 ` Lars-Peter Clausen 2016-08-09 9:12 ` Shawn Lin [not found] ` <1d42542f-c43c-5c4b-01b7-ba0ca085004a-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-17 8:11 ` Shawn Lin 2016-08-19 2:45 ` Vinod Koul 2016-08-21 1:00 ` Shawn Lin [not found] ` <d4574737-f7b7-2726-373c-31cc81274a32-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-22 6:04 ` Vinod Koul 2016-08-05 2:53 ` [PATCH 2/3] dmaengine: pl330: enable burst mode by parsing dt Shawn Lin 2016-08-07 9:20 ` Xing Zheng 2016-08-05 2:53 ` [PATCH 3/3] dmaengine: pl330: support transfer unaligned with (burst len * burst size) Shawn Lin [not found] ` <1470365602-32586-4-git-send-email-shawn.lin-TNX95d0MmH7DzftRWevZcw@public.gmane.org> 2016-08-07 9:21 ` Xing Zheng
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