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References: <20231214105243.3707730-1-tudor.ambarus@linaro.org> <20231214105243.3707730-10-tudor.ambarus@linaro.org>
In-Reply-To: <20231214105243.3707730-10-tudor.ambarus@linaro.org>
From:   Sam Protsenko <semen.protsenko@linaro.org>
Date:   Thu, 14 Dec 2023 09:42:53 -0600
Message-ID: <CAPLW+4kzdsuHiPqFuCbgD+595Kg3+mM8ziXr+D3K0LvEQXF_rQ@mail.gmail.com>
Subject: Re: [PATCH 09/13] arm64: dts: exynos: gs101: update USI UART to use
 peric0 clocks
To:     Tudor Ambarus <tudor.ambarus@linaro.org>
Cc:     peter.griffin@linaro.org, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, mturquette@baylibre.com,
        sboyd@kernel.org, conor+dt@kernel.org, andi.shyti@kernel.org,
        alim.akhtar@samsung.com, gregkh@linuxfoundation.org,
        jirislaby@kernel.org, catalin.marinas@arm.com, will@kernel.org,
        s.nawrocki@samsung.com, tomasz.figa@gmail.com,
        cw00.choi@samsung.com, arnd@arndb.de, andre.draszik@linaro.org,
        saravanak@google.com, willmcvicker@google.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
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On Thu, Dec 14, 2023 at 4:53=E2=80=AFAM Tudor Ambarus <tudor.ambarus@linaro=
.org> wrote:
>
> Get rid of the dummy clock and start using the cmu_peric0 clocks
> for the usi_uart and serial_0 nodes.
>
> Tested the serial at 115200, 1000000 and 3000000 baudrates,
> everthing went fine.
>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
> ---
>  arch/arm64/boot/dts/exynos/google/gs101.dtsi | 14 ++++----------
>  1 file changed, 4 insertions(+), 10 deletions(-)
>
> diff --git a/arch/arm64/boot/dts/exynos/google/gs101.dtsi b/arch/arm64/bo=
ot/dts/exynos/google/gs101.dtsi
> index d0b0ad70c6ba..ffb7b4d89a8c 100644
> --- a/arch/arm64/boot/dts/exynos/google/gs101.dtsi
> +++ b/arch/arm64/boot/dts/exynos/google/gs101.dtsi
> @@ -180,14 +180,6 @@ HERA_CPU_SLEEP: cpu-hera-sleep {
>                 };
>         };
>
> -       /* TODO replace with CCF clock */
> -       dummy_clk: clock-3 {
> -               compatible =3D "fixed-clock";
> -               #clock-cells =3D <0>;
> -               clock-frequency =3D <12345>;
> -               clock-output-names =3D "pclk";
> -       };
> -
>         /* ect node is required to be present by bootloader */
>         ect {
>         };
> @@ -369,7 +361,8 @@ usi_uart: usi@10a000c0 {
>                         ranges;
>                         #address-cells =3D <1>;
>                         #size-cells =3D <1>;
> -                       clocks =3D <&dummy_clk>, <&dummy_clk>;
> +                       clocks =3D <&cmu_peric0 CLK_GOUT_PERIC0_CLK_PERIC=
0_USI0_UART_CLK>,
> +                                <&cmu_peric0 CLK_DOUT_PERIC0_USI0_UART>;

Why using DIV clock here? Usually all leaf clocks are GATE clocks (at
least it's so in Exynos850).

>                         clock-names =3D "pclk", "ipclk";
>                         samsung,sysreg =3D <&sysreg_peric0 0x1020>;
>                         samsung,mode =3D <USI_V2_UART>;
> @@ -381,7 +374,8 @@ serial_0: serial@10a00000 {
>                                 reg-io-width =3D <4>;
>                                 interrupts =3D <GIC_SPI 634
>                                               IRQ_TYPE_LEVEL_HIGH 0>;
> -                               clocks =3D <&dummy_clk 0>, <&dummy_clk 0>=
;
> +                               clocks =3D <&cmu_peric0 CLK_GOUT_PERIC0_C=
LK_PERIC0_USI0_UART_CLK>,
> +                                        <&cmu_peric0 CLK_DOUT_PERIC0_USI=
0_UART>;

Ditto.

>                                 clock-names =3D "uart", "clk_uart_baud0";
>                                 samsung,uart-fifosize =3D <256>;
>                                 status =3D "disabled";
> --
> 2.43.0.472.g3155946c3a-goog
>