Re: [PATCH 3/3] arm64: dts: allwinner: a64: Add hwspinlock node

From: Andre Przywara <andre.przywara@arm.com>
To: Bastian Germann <bage@debian.org>
Cc: Wilken Gottwalt <wilken.gottwalt@posteo.net>,
	Ohad Ben-Cohen <ohad@wizery.com>,
	Bjorn Andersson <andersson@kernel.org>,
	Baolin Wang <baolin.wang@linux.alibaba.com>,
	Rob Herring <robh+dt@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Chen-Yu Tsai <wens@csie.org>,
	Samuel Holland <samuel@sholland.org>,
	linux-remoteproc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-sunxi@lists.linux.dev, devicetree@vger.kernel.org
Subject: Re: [PATCH 3/3] arm64: dts: allwinner: a64: Add hwspinlock node
Date: Tue, 14 Feb 2023 00:12:00 +0000	[thread overview]
Message-ID: <20230214001200.54504034@slackpad.lan> (raw)
In-Reply-To: <20230213231931.6546-4-bage@debian.org>

On Tue, 14 Feb 2023 00:19:30 +0100
Bastian Germann <bage@debian.org> wrote:

Hi,

> Add the hwspinlock to A64 which is already implemented for A31.
> 
> Signed-off-by: Bastian Germann <bage@debian.org>
> ---
>  arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> index 77b5349f6087..d4be8be0f2f3 100644
> --- a/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> +++ b/arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi
> @@ -851,6 +851,16 @@ wdt0: watchdog@1c20ca0 {
>  			clocks = <&osc24M>;
>  		};
>  
> +		hwspinlock: hwlock@1c18000 {
> +			compatible = "allwinner,sun6i-a31-hwspinlock";

I wonder if we should add a more specific compatible string here
(sun50i-a64-hwspinlock), with the existing one as a fallback.

Checked the address and the clock/reset against the manual.

I am not entirely sure if it's the best practice to unconditionally
enable those devices, but since it needs explicit consumers to be used,
it's probably fine.

Cheers,
Andre

> +			reg = <0x01c18000 0x1000>;
> +			clocks = <&ccu CLK_BUS_SPINLOCK>;
> +			clock-names = "ahb";
> +			resets = <&ccu RST_BUS_SPINLOCK>;
> +			reset-names = "ahb";
> +			#hwlock-cells = <1>;
> +		};
> +
>  		spdif: spdif@1c21000 {
>  			#sound-dai-cells = <0>;
>  			compatible = "allwinner,sun50i-a64-spdif",