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Message-ID: <66c41caf-bf21-61af-c6e4-52b34b69c1ce@linaro.org>
Date:   Thu, 20 Apr 2023 03:50:16 +0200
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Subject: Re: [PATCH RFT v2 00/14] SMD RPMCC sleep preparations
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To:     Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
Cc:     linux-arm-msm@vger.kernel.org, linux-clk@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        devicetree@vger.kernel.org, Shawn Guo <shawn.guo@linaro.org>,
        Taniya Das <quic_tdas@quicinc.com>
References: <20230303-topic-rpmcc_sleep-v2-0-ae80a325fe94@linaro.org>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <20230303-topic-rpmcc_sleep-v2-0-ae80a325fe94@linaro.org>
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On 8.03.2023 22:35, Konrad Dybcio wrote:
> v1 -> v2:
> - Use CLK_IS_CRITICAL instead of leaving a clk enable vote, expand macros
>   to do so
> - Fix the keepalive clocks for 8998 & 660 (CNoC -> PNoC, it was
>   confusingly named cnoc_periph downstream)
> - Introduce .determinte_rate to ensure we don't set keepalive clocks'
>   rates below 19.2 MHz
> - Add a (!conditional!) way to test the ultimate goal of all these changes
>   by essentially enabling unused clk cleanup through a dt property (for
>   legacy reasons)
> 
> v2 was tested on:
> 
> - MSM8996 Sony Kagura (can disable unused)
> - MSM8998 Sony Maple (can disable unused with OOT icc)
> - SM6375 Sony PDX225 (can disable unused with OOT icc)
> 
> v1: https://lore.kernel.org/r/20230303-topic-rpmcc_sleep-v1-0-d9cfaf9b27a7@linaro.org
> 
> This series brings support for a couple of things necessary for the full
> system idle on SMD RPM SoCs, namely unused clk shutdown and keepalive
> votes (permanent active votes that are required on certain clocks for the
> platform to function).
> 
> Tested on MSM8996 and SM6375, does not seem to introduce any additional
> regressions.
> 
> Keepalive clocks for other platforms were gathered by digging in old
> downstream kernels, please give them a test.
I have an implementation of rpmcc-within-icc ready(ish) locally. Turns out
some SoCs need a keepalive (19.2MHz, active-only) vote on clocks that
are NOT governed by interconnect.. So before we can disable clocks,
both will need to be implemented.. ugh... I was hoping we could avoid
having it in rpmcc..

Konrad
> 
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> ---
> Konrad Dybcio (11):
>       dt-bindings: clock: qcom,rpmcc: Add a way to enable unused clock cleanup
>       clk: qcom: smd-rpm_ Make __DEFINE_CLK_SMD_RPM_BRANCH_PREFIX accept flags
>       clk: qcom: smd-rpm: Make DEFINE_CLK_SMD_RPM_BRANCH_A accept flags
>       clk: qcom: smd-rpm: Make BI_TCXO_AO critical
>       clk: qcom: smd-rpm: Make __DEFINE_CLK_SMD_RPM_PREFIX accept flags
>       clk: qcom: smd-rpm: Separate out a macro for defining an AO clock
>       clk: qcom: smd-rpm: Add support for keepalive votes
>       clk: qcom: smd-rpm: Introduce DEFINE_CLK_SMD_RPM_BUS_KEEPALIVE
>       clk: qcom: smd-rpm: Hook up PCNoC_0 keep_alive
>       clk: qcom: smd-rpm: Hook up CNoC_1 and SNoC_2 keep_alive
>       arm64: dts: qcom: msm8996: Enable rpmcc unused clk disablement
> 
> Shawn Guo (3):
>       clk: qcom: smd-rpm: Add .is_enabled hook
>       clk: qcom: smd-rpm: Add .is_prepared hook
>       clk: qcom: smd-rpm: Mark clock enabled in clk_smd_rpm_handoff()
> 
>  .../devicetree/bindings/clock/qcom,rpmcc.yaml      |   6 +
>  arch/arm64/boot/dts/qcom/msm8996.dtsi              |   1 +
>  drivers/clk/qcom/clk-smd-rpm.c                     | 133 +++++++++++++++------
>  3 files changed, 106 insertions(+), 34 deletions(-)
> ---
> base-commit: fc31900c948610e7b5c2f15fb7795832c8325327
> change-id: 20230303-topic-rpmcc_sleep-d67aad9f3012
> 
> Best regards,