[PATCH 4/8] dt-bindings: Add Tegra264 clock and reset definitions

[Thierry Reding]

On Thu, May 08, 2025 at 10:42:33AM +0200, Krzysztof Kozlowski wrote:
> On 08/05/2025 09:53, Thierry Reding wrote:
> > On Thu, May 08, 2025 at 09:40:02AM +0200, Krzysztof Kozlowski wrote:
> >> On 07/05/2025 16:37, Thierry Reding wrote:
> >>> @@ -0,0 +1,9 @@
> >>> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> >>> +/* Copyright (c) 2022-2023, NVIDIA CORPORATION. All rights reserved. */
> >>> +
> >>> +#ifndef DT_BINDINGS_CLOCK_TEGRA264_CLOCK_H
> >>> +#define DT_BINDINGS_CLOCK_TEGRA264_CLOCK_H
> >>> +
> >>> +#define TEGRA264_CLK_CLK_S			2U
> >>
> >> Abstract IDs start from 0 or 1, not 2. Also drop "U".
> > 
> > These are not abstract IDs, they are defined by the BPMP ABI. We cannot
> > change them, otherwise it'll completely break.
> 
> 
> You mean from the firmware? Sure. You have entire commit msg to explain
> all unusual things here...

It's not unusual, though. This has been the convention for a number of
years now. But yeah, I guess I can be verbose and repeat all of these
details for each new generation...

> 
> > 
> > For similar reasons I'd like to keep the "U". These definitions are for
> > the most part directly imported from the BPMP ABI headers, though we do
> > try to be selective about what we add, to avoid adding hundreds of new
> > lines in one go, and several safety-checking tools run on these headers
> > that happen to require the "U" suffix to make sure these have a defined
> > type.
> > 
> >>> +
> >>> +#endif /* DT_BINDINGS_CLOCK_TEGRA264_CLOCK_H */
> >>> diff --git a/include/dt-bindings/reset/tegra264-reset.h b/include/dt-bindings/reset/tegra264-reset.h
> >>> new file mode 100644
> >>> index 000000000000..31d89dcf62fa
> >>> --- /dev/null
> >>> +++ b/include/dt-bindings/reset/tegra264-reset.h
> >>> @@ -0,0 +1,7 @@
> >>> +/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
> >>> +/* Copyright (c) 2022-2023, NVIDIA CORPORATION. All rights reserved. */
> >>> +
> >>> +#ifndef DT_BINDINGS_RESET_TEGRA264_RESET_H
> >>> +#define DT_BINDINGS_RESET_TEGRA264_RESET_H
> >>> +
> >> This is empty, drop.
> > 
> > We have three people currently working on additional drivers for this
> > SoC and they all need to add to these two files. Adding the empty file
> > here makes it a bit easier to coordinate things, making the resulting
> > conflicts trivial to resolve.
> 
> 
> Bindings are supposed to be complete (see writing bindings doc), this
> means also bindings headers. If the constants come from firmware, they
> are defined so I really do not understands why they cannot be published now.
> 
> Unless you mean that this is a new SoC and the firmware is not yet
> fixed/finished, but all this must be explained in the commit msg.

These are fully defined, but they are also close to 500 IDs, most of
which we won't be using for a long time, so it seems wasteful to dump
them all in here at once.

But I don't care all that much, if you want all of them, then that's
what you'll get.

Thierry
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20250508/c1033cac/attachment.sig>