On 07/02/2022 05:14, Alim Akhtar wrote: > Hi Krzysztof > >> -----Original Message----- >> From: Krzysztof Kozlowski [mailto:krzysztof.kozlowski@xxxxxxxxxxxxx] >> Sent: Sunday, February 6, 2022 7:28 PM >> To: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>; Rob Herring >> <robh+dt@xxxxxxxxxx>; Lukasz Luba <lukasz.luba@xxxxxxx>; Alim Akhtar >> <alim.akhtar@xxxxxxxxxxx>; Dmitry Osipenko <digetx@xxxxxxxxx>; linux- >> kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- >> pm@xxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx; linux-arm- >> kernel@xxxxxxxxxxxxxxxxxxx >> Subject: [PATCH v3 5/8] dt-bindings: memory: lpddr3: deprecate >> manufacturer ID >> >> The memory manufacturer should be described in vendor part of compatible, >> so there is no need to duplicate it in a separate property. >> Similarly is done in LPDDR2 bindings. >> >> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx> >> --- >> .../bindings/memory-controllers/ddr/jedec,lpddr3.yaml | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/devicetree/bindings/memory- >> controllers/ddr/jedec,lpddr3.yaml >> b/Documentation/devicetree/bindings/memory- >> controllers/ddr/jedec,lpddr3.yaml >> index d6787b5190ee..3bcba15098ea 100644 >> --- a/Documentation/devicetree/bindings/memory- >> controllers/ddr/jedec,lpddr3.yaml >> +++ b/Documentation/devicetree/bindings/memory- >> controllers/ddr/jedec,lpd >> +++ dr3.yaml >> @@ -40,7 +40,9 @@ properties: >> manufacturer-id: >> $ref: /schemas/types.yaml#/definitions/uint32 >> description: | >> - Manufacturer ID value read from Mode Register 5. >> + Manufacturer ID value read from Mode Register 5. The property is >> + deprecated, manufacturer should be derived from the compatible. >> + deprecated: true >> > > Shouldn't it be the other way? As DT describes hardware and MR5 does contain > the Manufacturer ID, > so getting Manufacturer ID from MR5 makes aligned to hardware description. The code/driver can read MR5 and report it to user-space in case for example we have a device compatible with different vendor and same compatible is used. So compatible is re-used but we want real manufacturer ID from the hardware. But storing a fixed MR5 value in DT does not fit here. If someone takes effort to encode manufacturer ID in the DTS, then he/she should take effort to actually document the compatible. Basically having MR5 in DT is equal to having a compatible in DTS. I prefer the latter - simpler, less properties, using existing property from DT spec instead of custom one. Best regards, Krzysztof
