Re: [PATCH v6 00/12] ARM/MIPS: DTS: add child nodes describing the PVRSGX GPU present in some OMAP SoC and JZ4780 (and many more)

From: Tony Lindgren
Date: Wed Apr 22 2020 - 15:33:40 EST


* Philipp Rossak <embed3d@xxxxxxxxx> [200422 19:05]:
> A few years back, I did a big research on the PowerVR GPUs. Back then I
> found an interesting TI datasheet. I forgot about this till I have seen the
> right buzz words. Sorry that I remembered it that late.
>
> Back then I came to the conclusion that all PowerVR GPU's have in general 3
> Clocks.
>
> A system clock, a memory clock and a core clock. [1].

Hmm I'm not sure if those names are sgx or SoC specific.

Anyways, the sgx clocks for omap variants are already handled
by the ti-sysc module as "fck" and "ick" so nothing to do there.

> The hyd_clk at sunxi devices seems to be the system clock.
>
> With those additional information it should be very easy to get a proper
> binding.

It would be best to find the clock(s) name used in the sgx docs
to avoid using SoC specific naming :)

But yeah "sysclk" "memclk" and "coreclk" seem just fine for
me for the optional clocks if that works for other SoCs.

Regards,

Tony

> [1]: https://github.com/embed-3d/PVRSGX_hwdoc/blob/master/sources/pdfs/Spruh73c_chapter_SGX_Graphics_Accelerator.pdf