From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Florian Fainelli" Subject: [PATCH 3/3] ARM: kernel: document ARM CPUs clocks and clock-frequency properties Date: Thu, 20 Jun 2013 15:39:06 +0100 Message-ID: <1371739146-32639-4-git-send-email-f.fainelli@gmail.com> References: <1371739146-32639-1-git-send-email-f.fainelli@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1371739146-32639-1-git-send-email-f.fainelli@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: lorenzo.pieralisi@arm.com Cc: Florian Fainelli , nico@linaro.org, devicetree-discuss@lists.ozlabs.org, rob.herring@calxeda.com, grant.likely@linaro.org, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org ARM CPU device tree nodes may contain a "clock-frequency" property, when set, this property must contain the CPU frequency in Hz, which is then used by the topology parsing code in arch/arm/kernel/topology.c to deduced the CPU capacity. The "clocks" property, if present shall be a phandle to a valid clock node. Document thes properties to avoid any possible confusion on the clock-frequency unit and also specify that "device_type" is also used by the topology code. Signed-off-by: Florian Fainelli --- Documentation/devicetree/bindings/arm/cpus.txt | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/arm/cpus.txt b/Documentation/devicetree/bindings/arm/cpus.txt index f32494d..1ce1ace 100644 --- a/Documentation/devicetree/bindings/arm/cpus.txt +++ b/Documentation/devicetree/bindings/arm/cpus.txt @@ -10,7 +10,7 @@ http://devicetree.org For the ARM architecture every CPU node must contain the following properties: -- device_type: must be "cpu" +- device_type: must be "cpu". Use by the topology code. - reg: property matching the CPU MPIDR[23:0] register bits reg[31:24] bits must be set to 0 - compatible: should be one of: @@ -45,6 +45,11 @@ For the ARM architecture every CPU node must contain the following properties: "marvell,xsc3" "marvell,xscale" +- clocks: phandle and clock specifier for the CPU clock, used if + "device_type" is present. +- clock-frequency: the frequency of the CPU, in Hz. Mandatory if "device_type" + is also present, used as fallback is "clocks" is not present. + Example: cpus { -- 1.8.1.2