From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lina Iyer Subject: Re: [PATCH 2/2] dt-bindings: introduce Command DB for QCOM SoCs Date: Tue, 30 Jan 2018 16:17:50 +0000 Message-ID: <20180130161750.GA20815@codeaurora.org> References: <20180118220833.16616-3-ilina@codeaurora.org> <20180118222802.18161-1-ilina@codeaurora.org> <20180129190852.5ddcgdo3gkc2nw5r@rob-hp-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Return-path: Content-Disposition: inline In-Reply-To: <20180129190852.5ddcgdo3gkc2nw5r@rob-hp-laptop> Sender: linux-arm-msm-owner@vger.kernel.org To: Rob Herring Cc: andy.gross@linaro.org, david.brown@linaro.org, sboyd@codeaurora.org, rnayak@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-soc@vger.kernel.org, msivasub@codeaurora.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org Thanks Rob, for taking time to review these bindings. On Mon, Jan 29 2018 at 19:08 +0000, Rob Herring wrote: >On Thu, Jan 18, 2018 at 03:28:02PM -0700, Lina Iyer wrote: >> From: Mahesh Sivasubramanian >> >> Command DB provides information on shared resources like clocks, >> regulators etc., probed at boot by the remote subsytem and made >> available in shared memory. >> >> Cc: devicetree@vger.kernel.org >> Signed-off-by: Mahesh Sivasubramanian >> Signed-off-by: Lina Iyer >> --- >> .../devicetree/bindings/arm/msm/cmd-db.txt | 37 ++++++++++++++++++++++ >> 1 file changed, 37 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/arm/msm/cmd-db.txt >> >> diff --git a/Documentation/devicetree/bindings/arm/msm/cmd-db.txt b/Documentation/devicetree/bindings/arm/msm/cmd-db.txt >> new file mode 100644 >> index 000000000000..b56e3e3604d3 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/arm/msm/cmd-db.txt >> @@ -0,0 +1,37 @@ >> +Command DB >> +--------- > >Another strange QCom binding... > :) >> + >> +Command DB is a database that provides a mapping between resource key and the >> +resource address for a system resource managed by a remote processor. The data >> +is stored in a shared memory region and is loaded by the remote processor. > >Is said shared memory described in DT. If so, this should be a child >node. Only 8 bytes seems kind of fine grained for putting in DT when it >could be implied by the parent shared memory node. > I dont believe this memory will be described in DT for this chipset. Will ask internally. >> + >> +Some of the Qualcomm Technologies Inc SoC's have hardware accelerators for >> +controlling shared resources. Depending on the board configuration the shared >> +resource properties may change. These properties are dynamically probed by the >> +remote processor and made available in the shared memory. > >The table may change, but does the presence of it or shared memory >location (of the pointer) change? > The location may change between different SoCs, but will be present in all chipsets of this architecture. Thanks, Lina >> + >> +Command DB allows drivers to query resource parameters based on pre-determined >> +key strings. >> + >> +The devicetree representation of the command DB driver should be: >> + >> +PROPERTIES: >> +- compatible: >> + Usage: required >> + Value type: >> + Definition: Should be "qcom,cmd-db" >> + >> +- reg: >> + Usage: required >> + Value type: >> + Definition: First element is the base address of shared memory >> + Second element is the size of the shared memory region >> + Points to the dictionary address that houses the command DB >> + start address and the size of the command DB region >> + >> +Example: >> + >> + qcom,cmd-db@c3f000c { >> + compatible = "qcom,cmd-db"; >> + reg = <0xc3f000c 0x8>; >> + }; >> -- >> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, >> a Linux Foundation Collaborative Project >> >> -- >> To unsubscribe from this list: send the line "unsubscribe devicetree" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html