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

[Michal Simek]

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@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/tree/drivers/nvmem/zynqmp_nvmem.c?h=v6.6-rc5#n39
>
> This defines the nvmem config, not what should be where.

If you have only one entry you are also saying where it is.

Thanks,
Michal