On Fri, 04 Aug 2017 18:41:20 +0530 Abhishek Sahu <absahu@xxxxxxxxxxxxxx> wrote: > On 2017-08-04 18:15, Boris Brezillon wrote: > > On Mon, 31 Jul 2017 21:35:57 +0530 > > Abhishek Sahu <absahu@xxxxxxxxxxxxxx> wrote: > > > >> On 2017-07-26 00:13, Abhishek Sahu wrote: > >> > On 2017-07-25 00:47, Rob Herring wrote: > >> >> On Wed, Jul 19, 2017 at 05:18:00PM +0530, Abhishek Sahu wrote: > >> >>> 1. QPIC NAND will use compatible string "qcom,qpic-nandc-v1.4.0" > >> >>> 2. QPIC NAND will 3 BAM channels: command, data tx and data rx > >> >>> while EBI2 NAND uses only single ADM channel. > >> >>> 3. CRCI is only required for ADM DMA and its not required for > >> >>> QPIC NAND. > >> >>> > >> >>> Signed-off-by: Abhishek Sahu <absahu@xxxxxxxxxxxxxx> > >> >>> --- > >> >>> .../devicetree/bindings/mtd/qcom_nandc.txt | 54 > >> >>> ++++++++++++++++++++-- > >> >>> 1 file changed, 51 insertions(+), 3 deletions(-) > >> >>> > >> >>> diff --git a/Documentation/devicetree/bindings/mtd/qcom_nandc.txt > >> >>> b/Documentation/devicetree/bindings/mtd/qcom_nandc.txt > >> >>> index b24adfe..8efaeb0 100644 > >> >>> --- a/Documentation/devicetree/bindings/mtd/qcom_nandc.txt > >> >>> +++ b/Documentation/devicetree/bindings/mtd/qcom_nandc.txt > >> >>> @@ -1,13 +1,15 @@ > >> >>> * Qualcomm NAND controller > >> >>> > >> >>> Required properties: > >> >>> -- compatible: should be "qcom,ebi2-nandc" - EBI2 NAND which uses > >> >>> ADM > >> >>> - DMA like IPQ8064. > >> >>> - > >> >>> +- compatible: must be one of the following: > >> >>> + * "qcom,ebi2-nandc" - EBI2 NAND which uses ADM DMA like IPQ8064. > >> >>> + * "qcom,qpic-nandc-v1.4.0" - QPIC NAND v1.4.0 which uses BAM DMA > >> >>> like IPQ4019. > >> >> > >> >> Looks like you have 2 SoCs and 2 versions of h/w. Use SoC specific > >> >> compatible strings. > >> > > >> > We have 3 versions of NAND HW currently. > >> > EBI2, > >> > QPIC version 1.4.0 > >> > QPIC version 1.5.0 > >> > > >> > and multiple Qualcomm SoCs which use any one of these. > >> > > >> > The original plan was to have compatible string for NAND version since > >> > same NAND hardware is being in different SoC and SoC dtsi will simply > >> > use its NAND version compatible string like other Qualcomm hardwares > >> > > >> > > >> > http://elixir.free-electrons.com/linux/latest/source/Documentation/devicetree/bindings/dma/qcom_bam_dma.txt > >> > > >> > http://elixir.free-electrons.com/linux/latest/source/Documentation/devicetree/bindings/spi/qcom,spi-qup.txt > >> > > >> > >> Following are the partial list for NAND controller and supported > >> SoC > >> > >> EBI2: IPQ8064, APQ8064, MSM7xx, MDM9x15 > >> QPIC v1.4.0 MDM9x25, MDM9x35, MDM9x45, IPQ4019 > >> QPIC v1.5.0 MDM9x55, IPQ8074 > >> > >> so could we use NAND controller specific compatible strings instead > >> of > >> SoC > >> since it will easy to maintain? > > > > Nope, though you can re-use the compatible of an old SoC for new SoCs > > if the IP did not change. > > > > For example: > > > > - EBI2: compatible = "qcom,ipq8064" > > - QPIC 1.4: compatible = "qcom,mdm9x25" > > - QPIC 1.5: compatible = "qcom,mdm9x55" > > > > Note that we usually pick the oldest SoC that started embedding an IP > > when choosing the compatible. So my suggestion assumes IPQ8064 is older > > than APQ8064, MSM7xx and MDM9x15. > > Thanks Boris for detailed clarification. > Then I will change the patch to use SoC specific compatible string. > > Its better to use qcom,ipq4019 for 1.4.0 and qcom,ipq8074 for 1.5.0 > since we don't have other SoC in upstream and I have tested the > NAND driver on these IPQ SoC's. Sounds good, but I'll let Rob confirm. -- 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
