Re: [PATCH v12 02/10] dt-bindings: introduce RPMH RSC bindings for Qualcomm SoCs

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Tue 19 Jun 06:11 PDT 2018, Raju P L S S S N wrote:

> From: Lina Iyer <ilina@codeaurora.org>
> 
> Add device binding documentation for Qualcomm Technology Inc's RPMH RSC
> driver. The driver is used for communicating resource state requests for
> shared resources.
> 
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Lina Iyer <ilina@codeaurora.org>
> Reviewed-by: Rob Herring <robh@kernel.org>
> [rplsssn@codeaurora.org: minor order correction for TCS type]

In accordance with section 11 of
Documentation/process/submitting-patches.rst you must to add your
Signed-off-by tag at the end of this list.

Same on patch 3.

Regards,
Bjorn

> ---
> Changes in v8:
> 	- Describe IRQ for all DRVs
> 
> Changes in v7:
> 	- Fix example
> 
> Changes in v6:
> 	- Address comments from Stephen Boyd
> 
> Changes in v3:
> 	- Move to soc/qcom
> 	- Amend text per Stephen's suggestions
> 
> Changes in v2:
> 	- Amend text to describe the registers in reg property
> 	- Add reg-names for the registers
> 	- Update examples to use GIC_SPI in interrupts instead of 0
> 	- Rephrase incorrect description
> 
> Changes in v3:
> 	- Fix unwanted capitalization
> 	- Remove clients from the examples, this doc does not describe
> 	  them
> 	- Rephrase introductory paragraph
> 	- Remove hardware specifics from DT bindings
> ---
>  .../devicetree/bindings/soc/qcom/rpmh-rsc.txt      | 137 +++++++++++++++++++++
>  1 file changed, 137 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt
> 
> diff --git a/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt b/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt
> new file mode 100644
> index 0000000..9b86d1e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/soc/qcom/rpmh-rsc.txt
> @@ -0,0 +1,137 @@
> +RPMH RSC:
> +------------
> +
> +Resource Power Manager Hardened (RPMH) is the mechanism for communicating with
> +the hardened resource accelerators on Qualcomm SoCs. Requests to the resources
> +can be written to the Trigger Command Set (TCS)  registers and using a (addr,
> +val) pair and triggered. Messages in the TCS are then sent in sequence over an
> +internal bus.
> +
> +The hardware block (Direct Resource Voter or DRV) is a part of the h/w entity
> +(Resource State Coordinator a.k.a RSC) that can handle multiple sleep and
> +active/wake resource requests. Multiple such DRVs can exist in a SoC and can
> +be written to from Linux. The structure of each DRV follows the same template
> +with a few variations that are captured by the properties here.
> +
> +A TCS may be triggered from Linux or triggered by the F/W after all the CPUs
> +have powered off to facilitate idle power saving. TCS could be classified as -
> +
> +	ACTIVE  /* Triggered by Linux */
> +	SLEEP   /* Triggered by F/W */
> +	WAKE    /* Triggered by F/W */
> +	CONTROL /* Triggered by F/W */
> +
> +The order in which they are described in the DT, should match the hardware
> +configuration.
> +
> +Requests can be made for the state of a resource, when the subsystem is active
> +or idle. When all subsystems like Modem, GPU, CPU are idle, the resource state
> +will be an aggregate of the sleep votes from each of those subsystems. Clients
> +may request a sleep value for their shared resources in addition to the active
> +mode requests.
> +
> +Properties:
> +
> +- compatible:
> +	Usage: required
> +	Value type: <string>
> +	Definition: Should be "qcom,rpmh-rsc".
> +
> +- reg:
> +	Usage: required
> +	Value type: <prop-encoded-array>
> +	Definition: The first register specifies the base address of the
> +		    DRV(s). The number of DRVs in the dependent on the RSC.
> +	            The tcs-offset specifies the start address of the
> +	            TCS in the DRVs.
> +
> +- reg-names:
> +	Usage: required
> +	Value type: <string>
> +	Definition: Maps the register specified in the reg property. Must be
> +	            "drv-0", "drv-1", "drv-2" etc and "tcs-offset". The
> +
> +- interrupts:
> +	Usage: required
> +	Value type: <prop-encoded-interrupt>
> +	Definition: The interrupt that trips when a message complete/response
> +	           is received for this DRV from the accelerators.
> +
> +- qcom,drv-id:
> +	Usage: required
> +	Value type: <u32>
> +	Definition: The id of the DRV in the RSC block that will be used by
> +		    this controller.
> +
> +- qcom,tcs-config:
> +	Usage: required
> +	Value type: <prop-encoded-array>
> +	Definition: The tuple defining the configuration of TCS.
> +	            Must have 2 cells which describe each TCS type.
> +	            <type number_of_tcs>.
> +	            The order of the TCS must match the hardware
> +	            configuration.
> +	- Cell #1 (TCS Type): TCS types to be specified -
> +	            ACTIVE_TCS
> +	            SLEEP_TCS
> +	            WAKE_TCS
> +	            CONTROL_TCS
> +	- Cell #2 (Number of TCS): <u32>
> +
> +- label:
> +	Usage: optional
> +	Value type: <string>
> +	Definition: Name for the RSC. The name would be used in trace logs.
> +
> +Drivers that want to use the RSC to communicate with RPMH must specify their
> +bindings as child nodes of the RSC controllers they wish to communicate with.
> +
> +Example 1:
> +
> +For a TCS whose RSC base address is is 0x179C0000 and is at a DRV id of 2, the
> +register offsets for DRV2 start at 0D00, the register calculations are like
> +this -
> +DRV0: 0x179C0000
> +DRV2: 0x179C0000 + 0x10000 = 0x179D0000
> +DRV2: 0x179C0000 + 0x10000 * 2 = 0x179E0000
> +TCS-OFFSET: 0xD00
> +
> +	apps_rsc: rsc@179c0000 {
> +		label = "apps_rsc";
> +		compatible = "qcom,rpmh-rsc";
> +		reg = <0x179c0000 0x10000>,
> +		      <0x179d0000 0x10000>,
> +		      <0x179e0000 0x10000>;
> +		reg-names = "drv-0", "drv-1", "drv-2";
> +		interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>,
> +			     <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>,
> +			     <GIC_SPI 5 IRQ_TYPE_LEVEL_HIGH>;
> +		qcom,tcs-offset = <0xd00>;
> +		qcom,drv-id = <2>;
> +		qcom,tcs-config = <ACTIVE_TCS  2>,
> +				  <SLEEP_TCS   3>,
> +				  <WAKE_TCS    3>,
> +				  <CONTROL_TCS 1>;
> +	};
> +
> +Example 2:
> +
> +For a TCS whose RSC base address is 0xAF20000 and is at DRV id of 0, the
> +register offsets for DRV0 start at 01C00, the register calculations are like
> +this -
> +DRV0: 0xAF20000
> +TCS-OFFSET: 0x1C00
> +
> +	disp_rsc: rsc@af20000 {
> +		label = "disp_rsc";
> +		compatible = "qcom,rpmh-rsc";
> +		reg = <0xaf20000 0x10000>;
> +		reg-names = "drv-0";
> +		interrupts = <GIC_SPI 129 IRQ_TYPE_LEVEL_HIGH>;
> +		qcom,tcs-offset = <0x1c00>;
> +		qcom,drv-id = <0>;
> +		qcom,tcs-config = <ACTIVE_TCS  0>,
> +				  <SLEEP_TCS   1>,
> +				  <WAKE_TCS    1>,
> +				  <CONTROL_TCS 0>;
> +	};
> -- 
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,\na Linux Foundation Collaborative Project
>