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References: <20240109125814.3691033-1-tudor.ambarus@linaro.org> <20240109125814.3691033-9-tudor.ambarus@linaro.org>
In-Reply-To: <20240109125814.3691033-9-tudor.ambarus@linaro.org>
From: Sam Protsenko <semen.protsenko@linaro.org>
Date: Tue, 16 Jan 2024 11:57:54 -0600
Message-ID: <CAPLW+4mUMx9RvFiS0L2U+_Fd_PzcHhmNbyR4cmUrYF3BVgb=Cw@mail.gmail.com>
Subject: Re: [PATCH v3 08/12] arm64: dts: exynos: gs101: remove reg-io-width
 from serial
To: Tudor Ambarus <tudor.ambarus@linaro.org>
Cc: peter.griffin@linaro.org, krzysztof.kozlowski+dt@linaro.org, 
	gregkh@linuxfoundation.org, mturquette@baylibre.com, sboyd@kernel.org, 
	robh+dt@kernel.org, conor+dt@kernel.org, andi.shyti@kernel.org, 
	alim.akhtar@samsung.com, jirislaby@kernel.org, s.nawrocki@samsung.com, 
	tomasz.figa@gmail.com, cw00.choi@samsung.com, 
	linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, 
	linux-clk@vger.kernel.org, devicetree@vger.kernel.org, 
	linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, 
	linux-serial@vger.kernel.org, andre.draszik@linaro.org, 
	kernel-team@android.com, willmcvicker@google.com
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On Tue, Jan 9, 2024 at 7:00=E2=80=AFAM Tudor Ambarus <tudor.ambarus@linaro.=
org> wrote:
>
> Remove the reg-io-width property in order to comply with the bindings.
>
> The entire bus (PERIC) on which the GS101 serial resides only allows
> 32-bit register accesses. The reg-io-width dt property is disallowed
> for the "google,gs101-uart" compatible and instead the iotype is
> inferred from the compatible.
>
> Reviewed-by: Peter Griffin <peter.griffin@linaro.org>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
> ---

Reviewed-by: Sam Protsenko <semen.protsenko@linaro.org>

Just out of curiosity (I probably missed the relevant discussion
earlier): what is the actual reason for moving 'reg-io-width' to the
driver's code as 'iotype'? I mean, what is the actual problem that's
being solved by this -- is it to make the earlycon functional for
gs101? I'm asking because the bus width looks like a part of HW
description, which usually belongs to dts, from the design point of
view. Anyways, that's not a concern, just trying to understand the
decision.

> v3: collect Peter's R-b tag
> v2: new patch
>
>  arch/arm64/boot/dts/exynos/google/gs101.dtsi | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/exynos/google/gs101.dtsi b/arch/arm64/bo=
ot/dts/exynos/google/gs101.dtsi
> index d838e3a7af6e..4e5f4c748906 100644
> --- a/arch/arm64/boot/dts/exynos/google/gs101.dtsi
> +++ b/arch/arm64/boot/dts/exynos/google/gs101.dtsi
> @@ -366,7 +366,6 @@ usi_uart: usi@10a000c0 {
>                         serial_0: serial@10a00000 {
>                                 compatible =3D "google,gs101-uart";
>                                 reg =3D <0x10a00000 0xc0>;
> -                               reg-io-width =3D <4>;
>                                 interrupts =3D <GIC_SPI 634
>                                               IRQ_TYPE_LEVEL_HIGH 0>;
>                                 clocks =3D <&dummy_clk 0>, <&dummy_clk 0>=
;
> --
> 2.43.0.472.g3155946c3a-goog
>
>