[PATCH 2/5] dt-bindings: nvmem: Convert xlnx,zynqmp-nvmem.txt to yaml

[Kundanala, Praveen Teja]

[AMD Official Use Only - General]

> -----Original Message-----
> From: Simek, Michal <michal.simek at amd.com>
> Sent: Monday, October 16, 2023 1:32 PM
> To: Krzysztof Kozlowski <krzysztof.kozlowski at linaro.org>; Kundanala, Praveen
> Teja <praveen.teja.kundanala at amd.com>; srinivas.kandagatla at linaro.org;
> robh+dt at kernel.org; krzysztof.kozlowski+dt at linaro.org; conor+dt at kernel.org;
> devicetree at vger.kernel.org; linux-arm-kernel at lists.infradead.org
> Cc: linux-kernel at vger.kernel.org
> Subject: Re: [PATCH 2/5] dt-bindings: nvmem: Convert xlnx,zynqmp-nvmem.txt
> to yaml
>
>
>
> On 10/13/23 15:10, Krzysztof Kozlowski wrote:
> > On 13/10/2023 15:06, Michal Simek wrote:
> >>
> >>
> >> On 10/13/23 14:54, Krzysztof Kozlowski wrote:
> >>> On 13/10/2023 14:08, Michal Simek wrote:
> >>>>
> >>>>
> >>>> On 10/13/23 13:58, Krzysztof Kozlowski wrote:
> >>>>> On 13/10/2023 13:51, Michal Simek wrote:
> >>>>>>
> >>>>>>
> >>>>>> On 10/13/23 13:46, Krzysztof Kozlowski wrote:
> >>>>>>> On 13/10/2023 13:22, Michal Simek wrote:
> >>>>>>>>>
> >>>>>>>>>> +
> >>>>>>>>>> +required:
> >>>>>>>>>> +  - compatible
> >>>>>>>>>
> >>>>>>>>> required: block goes after patternProperties: block
> >>>>>>>>>
> >>>>>>>>>> +
> >>>>>>>>>> +patternProperties:
> >>>>>>>>>> +  "^soc_revision at 0$":
> >>>>>>>>>
> >>>>>>>>> Why do you define individual memory cells? Is this part of a
> binding?
> >>>>>>>>> IOW, OS/Linux requires this?
> >>>>>>>>
> >>>>>>>> nvmem has in kernel interface where you can reference to nodes.
> >>>>>>>> nvmem_cell_get() calls. It means you should be able to describe
> >>>>>>>> internal layout that's why names are used. And address in name
> >>>>>>>> is there because of reg property is used to describe base offset and
> size.
> >>>>>>>
> >>>>>>> That's not really what I am asking. Why internal layout of
> >>>>>>> memory must be part of the bindings?
> >>>>>>
> >>>>>> It doesn't need to be but offsets are hardcoded inside the driver
> >>>>>> itself and they can't be different.
> >>>>>
> >>>>> Hm, where? I opened drivers/nvmem/zynqmp_nvmem.c and I do not
> see
> >>>>> any hard-coded offsets.
> >>>>
> >>>> Current driver supports only soc revision from offset 0.
> >>>> But if you look at 5/5 you need to define offsets where information is
> present.
> >>>> +#define SOC_VERSION_OFFSET      0x0
> >>>> +#define EFUSE_START_OFFSET      0xC
> >>>> +#define EFUSE_END_OFFSET        0xFC
> >>>> +#define EFUSE_PUF_START_OFFSET  0x100
> >>>> +#define EFUSE_PUF_MID_OFFSET    0x140
> >>>> +#define EFUSE_PUF_END_OFFSET    0x17F
> >>>
> >>> There is nothing like this in existing driver, so the argument that
> >>> "I am adding this to the binding during conversion because driver needs it"
> >>> is not true. Conversion is only a conversion.
> >>
> >> Conversion in 2/5 is adding only soc revision which is already there.
> >> It is starting from 0 and world size is 1. And 0 is not listed
> >> because that's start all the time.
> >>
> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tr
> >> ee/drivers/nvmem/zynqmp_nvmem.c?h=v6.6-rc5#n39
> >
> > This defines the nvmem config, not what should be where.
> >
> >>
> >> And soc revision was also listed in origin binding example.
> >
> > Example is not a binding. Please drop enforcement of some specific
> > nodes from the binding.
>
> ok. Fine.
> Praveen: Please drop that descriptions about sub nodes.
>[Kundanala, Praveen Teja] Okay.
>
> Thanks,
> Michal