From mboxrd@z Thu Jan  1 00:00:00 1970
From: alexandre.belloni@free-electrons.com (Alexandre Belloni)
Date: Fri, 1 Jul 2016 20:32:49 +0200
Subject: [PATCH 2/2] ARM: dts: at91: sama5d2: add ETM, ETB and ETMCK node
In-Reply-To: <1467383831-6985-2-git-send-email-olivier.schonken@gmail.com>
References: <1467383831-6985-1-git-send-email-olivier.schonken@gmail.com>
 <1467383831-6985-2-git-send-email-olivier.schonken@gmail.com>
Message-ID: <20160701183248.GC2874@piout.net>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 01/07/2016 at 16:37:11 +0200, Olivier Schonken wrote :
> Add node to support SAMA5D2 Embedded Trace Macrocell and Embedded
> Trace Buffer. Add a dummy clock node needed by drivers/amba/bus.c
> for succesfull probe. The coresight clock is always present, and
> can thus not be enabled/disabled by a register write.
> 
> This patch depends on coresight-etm3x: Add ARM ETM-A5 peripheral ID
> for proper functionality.
> 
> Signed-off-by: Olivier Schonken <olivier.schonken@gmail.com>
> ---
>  arch/arm/boot/dts/sama5d2.dtsi | 44 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 44 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/sama5d2.dtsi b/arch/arm/boot/dts/sama5d2.dtsi
> index 5d63206..4a3a3fb 100644
> --- a/arch/arm/boot/dts/sama5d2.dtsi
> +++ b/arch/arm/boot/dts/sama5d2.dtsi
> @@ -77,6 +77,37 @@
>  		interrupts = <2 IRQ_TYPE_LEVEL_HIGH 0>;
>  	};
>  
> +	etb: etb at 00740000 {
> +		compatible = "arm,coresight-etb10", "arm,primecell";
> +		reg = <0x740000 0x1000>;
> +		status = "okay";
> +
> +		clocks = <&etmck>;
> +		clock-names = "apb_pclk";
> +
> +		port {
> +			etb_in: endpoint {
> +				slave-mode;
> +				remote-endpoint = <&etm_out>;
> +			};
> +		};
> +	};
> +
> +	etm: etm at 0073C000 {
> +		compatible = "arm,coresight-etm3x", "arm,primecell";
> +		reg = <0x73C000 0x1000>;
> +		status = "okay";
> +
> +		clocks = <&etmck>;
> +		clock-names = "apb_pclk";
> +
> +		port {
> +			etm_out: endpoint {
> +				remote-endpoint = <&etb_in>;
> +			};
> +		};
> +	};
> +
>  	memory {
>  		reg = <0x20000000 0x20000000>;
>  	};
> @@ -474,6 +505,19 @@
>  					};
>  				};
>  
> +				/*
> +				 * This is a dummy clock needed by
> +				 * drivers/amba/bus.c when probing
> +				 * for ETM/ETB. On SAMA5D2 the coresight
> +				 * clock is always supplied.
> +				*/
> +
> +				etmck: etmck {
> +					#clock-cells = <0>;
> +					compatible = "fixed-clock";
> +					clock-frequency = <0>;
> +				};
> +

Hum, maybe you could take mck instead of adding a dummy clock in the
PCM.

Boris, do you have a better idea?

-- 
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com