Hello Scott, On 10/30/2014 09:51 AM, Scott Wood wrote: > On Wed, 2014-10-29 at 23:32 -0500, Emil Medve wrote: >> Hello Scott, >> >> >> On 10/29/2014 05:16 PM, Scott Wood wrote: >>> On Wed, 2014-10-29 at 16:40 -0500, Emil Medve wrote: >>>> Hello Scott, >>>> >>>> >>>> On 10/28/2014 01:08 PM, Scott Wood wrote: >>>>> On Tue, 2014-10-28 at 09:36 -0500, Kumar Gala wrote: >>>>>> On Oct 22, 2014, at 9:09 AM, Emil Medve <Emilian.Medve@xxxxxxxxxxxxx> wrote: >>>>>> >>>>>>> The Buffer Manager is part of the Data-Path Acceleration Architecture (DPAA). >>>>>>> BMan supports hardware allocation and deallocation of buffers belonging to >>>>>>> pools originally created by software with configurable depletion thresholds. >>>>>>> This binding covers the CCSR space programming model >>>>>>> >>>>>>> Signed-off-by: Emil Medve <Emilian.Medve@xxxxxxxxxxxxx> >>>>>>> Change-Id: I3ec479bfb3c91951e96902f091f5d7d2adbef3b2 >>>>>>> --- >>>>>>> .../devicetree/bindings/powerpc/fsl/bman.txt | 98 ++++++++++++++++++++++ >>>>>>> 1 file changed, 98 insertions(+) >>>>>>> create mode 100644 Documentation/devicetree/bindings/powerpc/fsl/bman.txt >>>>>> >>>>>> Should these really be in bindings/powerpc/fsl, aren’t you guys using this on ARM SoCs as well? >>>>> >>>>> The hardware on the ARM SoCs is different enough that I'm not sure the >>>>> same binding will cover it. That said, putting things under <arch> >>>>> should be a last resort if nowhere else fits. >>>> >>>> OTC started ported the driver to the the ARM SoC and the feedback has >>>> been that the driver needed minimal changes. The IOMMU has been the only >>>> area of concern, and a small change to the binding has been suggested >>> >>> Do we need something in the binding to indicate device endianness? >> >> As I said, I didn't have enough exposure to the ARM SoC so I can't >> answer that >> >>> If this binding is going to continue to be relevant to future DPAA >>> generations, I think we really ought to deal with the possibility that >>> there is more than one datapath instance >> >> I'm unsure how relevant this will be going forward. In LS2 B/QMan is >> abstracted/hidden away behind the MC (firmware). > > This is why I was wondering whether the binding would be at all the > same... > >> I wouldn't over-engineer this without a clear picture of what multiple >> data-paths per SoC even means at this point > > I don't think it's over-engineering. Assuming only one instance of > something is generally sloppy engineering. Linux doesn't need to > actually pay attention to it until and unless it becomes necessary, but > it's good to have the information in the device tree up front. I asked around and the "multiple data-path SoC" seems to be at this point a speculation. It seems unclear how would it work, what requirements/problems it would address/solve, what programming interface it would have. I'm not sure what do you suggest we do In order to reduce the sloppiness of this binding. I'll add a memory-region phandle to connect each B/QMan node to their reserved-memory node >>> by having phandles and/or a parent container to connect the related >>> components. >> >> Connecting the related components is beyond the scope of this binding. >> It will soon hit the e-mail list(s) as part of upstreaming the Ethernet >> driver > > So you want us to merge this binding without being told how this works? This binding stands on its own and each block (B/QMan) can be used for some useful purpose by itself. All other blocks/applications that use the B/QMan use the same basic interface acquire/release a "buffer" and enqueue/dequeue a "packet". I'm not sure what you feel I didn't share > Or by "soon" do you mean before this binding is accepted? No. The Ethernet driver, the QI SEC driver, RMan driver, etc. employ the B/QMan and *other* hardware resources in some specific way. I don't think their binding/drivers condition accepting the B/QMan binding/driver Cheers, -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
