On Sunday, 30 June 2024 11:07:47 CEST Heiko Stübner wrote: > Am Sonntag, 30. Juni 2024, 00:01:41 CEST schrieb Diederik de Haas: > > On Saturday, 29 June 2024 18:39:02 CEST Dragan Simic wrote: > > > Add support for voltage ranges to the GPU OPPs defined in the SoC > > > dtsi for RK356x. These voltage ranges are useful for RK356x-based > > > boards that are designed to use the same power supply for the GPU > > > and NPU portions of the SoC, which is described further in the > > > following documents: > > > - Rockchip RK3566 Hardware Design Guide, version 1.1.0, page 37 > > > - Rockchip RK3568 Hardware Design Guide, version 1.2, page 78 > > > > That was interesting to read, thanks. > > Now I understand the difference between rk809(-5) and rk817(-5). > > > > But AFAIUI the above description described why there were separate tables > > for rk809 and rk817 in v1. But that was dropped in v2. So it seems to me > > the (commit) message should be updated accordingly? > > > > I also expected that (for v1) there would be a similar construct as was > > recently added for rk3588. But I should interpret Heiko's comments as that > > strategy should not be applied to rk356x? > > The issue I had was more about the #ifdef'ery and then having a board define > a constant to enable one or the other. Yeah, I had some thoughts about that too, but by the time I was ready to respond to that, there was v2, so that became irrelevant. > As far as I understood the description, the OPP itself is the same in > terms of frequency and voltage, just the regulator can't fully realize > that target voltage, so the solution is to allow a voltage range, to > also support the less-exact regulator. > > On the rk3588 on the other hand the soc variants have different OPP > tables themselfs, because the soc itself only supports different > frequencies+voltages. So the solution here is the split of the OPPs so > that we don't mess around with /delete-node/ edits of one OPP table. > > So TL;DR separate OPP tables are the way to go if the user needs different > freq+voltage values and voltage ranges allows boards to use less-adapted > regulators. Thanks for the explanation. One of the things I researched was whether there was a different OPP table in Rockchip's rk3566.dtsi (and then the assumption that RK817 = RK3566 and RK809 = RK3568, which would be flawed/incorrect). But there wasn't. Cheers, Diederik
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