Re: [PATCH v3 1/3] dt-bindings: remoteproc: k3-m4f: Add bindings for K3 AM64x SoCs
From: Martyn Welch
Date: Tue Mar 07 2023 - 13:36:58 EST
On Fri, 2023-03-03 at 09:06 +0100, Krzysztof Kozlowski wrote:
> On 02/03/2023 18:14, Martyn Welch wrote:
>
> > +
> > + mboxes:
> > + description: |
> > + OMAP Mailbox specifier denoting the sub-mailbox, to be used
> > for
>
> OMAP?
>
This device uses a mailbox compatible with the OMAP Mailbox, as defined
in Documentation/devicetree/bindings/mailbox/ti,omap-mailbox.yaml.
I note that documents title reads "TI OMAP2+ and K3 Mailbox devices".
I'll drop the "OMAP" here.
> > + communication with the remote processor. This property
> > should match
> > + with the sub-mailbox node used in the firmware image.
> > + maxItems: 1
> > +
> > + memory-region:
> > + description: |
> > + phandle to the reserved memory nodes to be associated with
> > the
> > + remoteproc device. There should be at least two reserved
> > memory nodes
> > + defined.
>
> Don't repeat constraints in free form text.
>
> > The reserved memory nodes should be carveout nodes, and
> > + should be defined with a "no-map" property as per the
> > bindings in
> > + Documentation/devicetree/bindings/reserved-memory/reserved-
> > memory.yaml
> > + minItems: 2
> > + maxItems: 8
> > + items:
> > + - description: region used for dynamic DMA allocations like
> > vrings and
> > + vring buffers
> > + - description: region reserved for firmware image sections
> > + additionalItems: true
>
> And what is the purpose of the rest of reserved nodes?
>
Up to 8 regions can be specified with their purpose determined by the
firmware running on the M4F core. The suggestion (and the
implementation in the example firmware) is to use the first 2 regions
as defined above for remoteproc with the others available to be used
for other purposes if necessary. The address translation module used
can cope with up to 8 regions.
>
Martyn