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. -- 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
