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Date:   Sat, 28 Oct 2023 13:30:45 +0200
From:   Stanislav Jakubek <stano.jakubek@gmail.com>
To:     Conor Dooley <conor@kernel.org>
Cc:     Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Florian Fainelli <florian.fainelli@broadcom.com>,
        Ray Jui <rjui@broadcom.com>,
        Scott Branden <sbranden@broadcom.com>,
        bcm-kernel-feedback-list@broadcom.com, linux-clk@vger.kernel.org,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
        Artur Weber <aweber.kernel@gmail.com>
Subject: Re: [PATCH v2] dt-bindings: clock: brcm,kona-ccu: convert to YAML
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On Fri, Oct 27, 2023 at 03:47:48PM +0100, Conor Dooley wrote:
> On Tue, Oct 24, 2023 at 06:45:21PM +0200, Stanislav Jakubek wrote:
> > Convert Broadcom Kona family clock controller unit (CCU) bindings
> > to DT schema.
> 
> I didn't cross-check the clock-output-names, but this conversion mostly
> looks good to me.
> 
> > Changes during conversion:
> >   - remove "dmac" from clock-output-names for brcm,bcm11351-master-ccu,
> >     it is not used in DT nor the dt-bindings
> >   - remove "uartb4" from clock-output-names for brcm,bcm21664-slave-ccu,
> >     it is not used in DT nor the dt-bindings
> 
> This I'm not sure about - they _were_ documented in the text-form
> dt-binding, even if they weren't used in the dts. If the clock
> controller does actually produce these clocks, removing them doesn't
> make sense to me.

Hi Conor. Looking at downstream, I was not able to find these clocks, though
I admit that I'm not familiar enough with the downstream mess to be 100%
confident.

From what I can tell, the BCM21664 arch/arm/mach-hawaii/clock.c (e.g. [1])
doesn't contain any mention of uartb4, only uartb, uartb2 and uartb3.
And similarly, for the BCM281XX arch/arm/mach-capri/clock_capri.c (e.g. [2])
I wasn't able to find any mention of dmac, only dmac_mux_apb and dma_axi
(though these two don't seem to be supported on mainline yet).

Judging by that and the fact that mainline Linux or the dt-bindings includes
don't mention these clocks either, I would say the old txt bindings document
was the wrong one.

The old clock-output-name table also didn't match with the dt-bindings include
it was supposedly describing - for example, BCM281XX_MASTER_CCU_USB_IC is
defined as 4, not 5 as the old table stated.

[1] https://github.com/Samsung-KYLEPROXX/android_kernel_samsung_kyleproxx/blob/cm-14.1/arch/arm/mach-hawaii/clock.c
[2] https://github.com/surblazer/android_kernel_samsung_galaxys2plus-common/blob/android-7.1/arch/arm/mach-capri/clock_capri.c

Thanks,
Stanislav

> 
> Cheers,
> Conor.