Re: [PATCH v3 2/3] powerpc/512x: add a device tree binding for LocalPlus Bus FIFO
On 28.09.2015 16:26, Timur Tabi wrote: > Alexander Popov wrote: >> I've just followed devicetree/bindings/dma/dma.txt... >> This "rx-tx" doesn't mean much but it could show that LocalPlus Bus FIFO >> uses a single DMA read-write channel. Should I really drop it? > > Hmmm, I'm not sure. Is there anything else (besides your driver) that > parses this device tree node? No, mpc512x_lpbfifo.c is the only piece of code which is going to use this device tree node. > dma.txt says this: > > "The specific strings that can be used are defined in the binding of the > DMA client device." > > So this looks like it's driver-specific, Yes. MPC512x LocalPlus Bus FIFO uses the channel #26 of the DMA controller both for reading and writing, and other DMA clients use other specific DMA channels. This channel assignment is fixed in hardware and described in the Reference Manual. > but it is a required property. > I guess you should keep it, but I think you should get a second opinion. Ok, thanks. Best regards, Alexander ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
Re: [PATCH v3 2/3] powerpc/512x: add a device tree binding for LocalPlus Bus FIFO
On 25.09.2015 03:18, Timur Tabi wrote: > Alexander Popov wrote: >> +- dma-names: should be "rx-tx"; > > Why bother, if it can only be one value? I've just followed devicetree/bindings/dma/dma.txt... This "rx-tx" doesn't mean much but it could show that LocalPlus Bus FIFO uses a single DMA read-write channel. Should I really drop it? Best regards, Alexander ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
Re: [PATCH v3 2/3] powerpc/512x: add a device tree binding for LocalPlus Bus FIFO
Alexander Popov wrote: I've just followed devicetree/bindings/dma/dma.txt... This "rx-tx" doesn't mean much but it could show that LocalPlus Bus FIFO uses a single DMA read-write channel. Should I really drop it? Hmmm, I'm not sure. Is there anything else (besides your driver) that parses this device tree node? dma.txt says this: "The specific strings that can be used are defined in the binding of the DMA client device." So this looks like it's driver-specific, but it is a required property. I guess you should keep it, but I think you should get a second opinion. ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
Re: [PATCH v3 2/3] powerpc/512x: add a device tree binding for LocalPlus Bus FIFO
Alexander Popov wrote: +- dma-names: should be "rx-tx"; Why bother, if it can only be one value? ___ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
