Re: [PATCH 08/10] mtd: flash-sam: Bindings for Juniper's SAM FPGA flash

From: Pantelis Antoniou
Date: Mon Oct 17 2016 - 15:04:36 EST


Hi Rob,

> On Oct 10, 2016, at 23:07 , Rob Herring <robh@xxxxxxxxxx> wrote:
>
> gOn Fri, Oct 07, 2016 at 06:18:36PM +0300, Pantelis Antoniou wrote:
>> From: Georgi Vlaev <gvlaev@xxxxxxxxxxx>
>>
>> Add binding document for Junipers Flash IP block present
>> in the SAM FPGA on PTX series of routers.
>>
>> Signed-off-by: Georgi Vlaev <gvlaev@xxxxxxxxxxx>
>> [Ported from Juniper kernel]
>> Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
>> ---
>> .../devicetree/bindings/mtd/flash-sam.txt | 31 ++++++++++++++++++++++
>> 1 file changed, 31 insertions(+)
>> create mode 100644 Documentation/devicetree/bindings/mtd/flash-sam.txt
>>
>> diff --git a/Documentation/devicetree/bindings/mtd/flash-sam.txt b/Documentation/devicetree/bindings/mtd/flash-sam.txt
>> new file mode 100644
>> index 0000000..bdf1d78
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/mtd/flash-sam.txt
>> @@ -0,0 +1,31 @@
>> +Flash device on a Juniper SAM FPGA
>> +
>> +These flash chips are found in the PTX series of Juniper routers.
>> +
>> +They are regular CFI compatible (Intel or AMD extended) flash chips with
>> +some special write protect/VPP bits that can be controlled by the machine's
>> +system controller.
>
> And where's the description of the sys ctrlr?
>

The system controller is Juniper IP. Weâll have to ask around about
specifics, and itâs pretty uninspiring stuff.

>> +
>> +Required properties:
>> +- compatible : must be "jnx,flash-sam"
>> +
>> +Optional properties:
>> +- reg : memory address for the flash chip, note that this is not
>> +required since usually the device is a subdevice of the SAM MFD
>> +driver which fills in the register fields.
>> +
>> +For the rest of the properties, see mtd-physmap.txt.
>> +
>> +The device tree may optionally contain sub-nodes describing partitions of the
>> +address space. See partition.txt for more detail.
>> +
>> +Example:
>> +
>> +flash_sam {
>> + compatible = "jnx,flash-sam";
>> + partition@0 {
>
> This should have a heirarchy of a controller node, a flash child node,
> partitions child node, and partition child nodes.
>

OK.

>> + reg = <0x0 0x400000>;
>> + label = "pic0-golden";
>> + read-only;
>> + };
>> +};
>> --
>> 1.9.1