Re: [PATCH v2 3/3] dt-bindings: hwinfo: Add mtk-socinfo driver

From: AngeloGioacchino Del Regno
Date: Wed Sep 20 2023 - 09:46:14 EST


Il 18/09/23 13:59, Krzysztof Kozlowski ha scritto:
On 18/09/2023 10:47, AngeloGioacchino Del Regno wrote:
Il 17/09/23 10:26, Krzysztof Kozlowski ha scritto:
On 15/09/2023 17:26, William-tw Lin wrote:
dt-binding documentation for mtk-socinfo driver.

Here and in subject, drop driver and instead descrbe hardware.

mtk-socinfo driver provides SoC-related information.
Such information includes manufacturer information, SoC name,
SoC segment name, and SoC marketing name.

Signed-off-by: William-tw Lin <william-tw.lin@xxxxxxxxxxxx>
---
.../bindings/hwinfo/mtk-socinfo.yaml | 48 +++++++++++++++++++
1 file changed, 48 insertions(+)
create mode 100644 Documentation/devicetree/bindings/hwinfo/mtk-socinfo.yaml

diff --git a/Documentation/devicetree/bindings/hwinfo/mtk-socinfo.yaml b/Documentation/devicetree/bindings/hwinfo/mtk-socinfo.yaml
new file mode 100644
index 000000000000..74f03f1dc404
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwinfo/mtk-socinfo.yaml

Nothing improved.

This is a friendly reminder during the review process.

It seems my previous comments were not fully addressed. Maybe my
feedback got lost between the quotes, maybe you just forgot to apply it.
Please go back to the previous discussion and either implement all
requested changes or keep discussing them.

Thank you.

@@ -0,0 +1,48 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwinfo/mtk-socinfo.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek SoC ChipID
+
+maintainers:
+ - William Lin <william-tw.lin@xxxxxxxxxxxx>
+ - Matthias Brugger <matthias.bgg@xxxxxxxxx>
+ - Kevin Hilman <khilman@xxxxxxxxxx>
+ - AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
+
+description:
+ MediaTek SoCs store various product information in eFuses, including
+ Chip ID and Revision fields, usable to identify the manufacturer,
+ SoC version, plus segment and marketing names.
+
+properties:
+ compatible:
+ const: mediatek,socinfo

What happened to compatibles? No, this is just wrong and no explained.
You ignored other comments as well. Really, that's not the way to go.


Practically, having different compatibles for each SoC is not needed, as
the only thing that changes between SoCs is the eFuse(s) that you read to
get the information - and that's all.


And how do you guarantee that no future SoC will have any difference?
How can you even predict it?


You're right, it's too much long sighted and at some point in the future this
assumption will be *inevitably* wrong.

Thanks,
Angelo


So ... we either use this driver with devicetree, giving it the right eFuses

I am talking about bindings, no driver.

to read from, or we duplicate the mtk-efuse driver, or we statically assign
the eFuses in the driver itself and we set compatibles like
"mediatek,mt8195-socinfo" to select that... ideas?

Device specific compatibles followed by fallback, just like for every
other review coming from me.
> Best regards,
Krzysztof