From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: [PATCH v7 5/7] qcom: cpuidle: Add cpuidle driver for QCOM cpus Date: Tue, 30 Sep 2014 10:41:14 -0700 Message-ID: <7hmw9hypj9.fsf@deeprootsystems.com> References: <1411779495-39724-1-git-send-email-lina.iyer@linaro.org> <1411779495-39724-6-git-send-email-lina.iyer@linaro.org> <20140929153154.GF2165@e102568-lin.cambridge.arm.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <20140929153154.GF2165@e102568-lin.cambridge.arm.com> (Lorenzo Pieralisi's message of "Mon, 29 Sep 2014 16:31:55 +0100") Sender: linux-pm-owner@vger.kernel.org To: Lorenzo Pieralisi Cc: Lina Iyer , "daniel.lezcano@linaro.org" , "sboyd@codeaurora.org" , "galak@codeaurora.org" , "linux-arm-msm@vger.kernel.org" , "linux-pm@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "msivasub@codeaurora.org" List-Id: linux-arm-msm@vger.kernel.org Lorenzo Pieralisi writes: > Hi Lina, > > On Sat, Sep 27, 2014 at 01:58:13AM +0100, Lina Iyer wrote: >> Add cpuidle driver interface to allow cpus to go into C-States. Use the >> cpuidle DT interface common across ARM architectures to provide the >> C-State information to the cpuidle framework. >> >> Supported modes at this time are clock gating (wfi) and cpu power down >> (Standalone PC or spc). >> >> Signed-off-by: Lina Iyer >> --- >> .../bindings/arm/msm/qcom,idle-state.txt | 72 +++++++++++++++++ >> drivers/cpuidle/Kconfig.arm | 7 ++ >> drivers/cpuidle/Makefile | 1 + >> drivers/cpuidle/cpuidle-qcom.c | 89 ++++++++++++++++++++++ >> 4 files changed, 169 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt >> create mode 100644 drivers/cpuidle/cpuidle-qcom.c >> >> diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt b/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt >> new file mode 100644 >> index 0000000..47095b9 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt >> @@ -0,0 +1,72 @@ >> +QCOM Idle States for cpuidle driver >> + >> +ARM provides idle-state node to define the cpuidle states, as defined in [1]. >> +cpuidle-qcom is the cpuidle driver for Qualcomm SoCs and uses these idle >> +states. Idle states have different enter/exit latency and residency values. >> +The idle states supported by the QCOM SoC are defined as - >> + >> + * WFI >> + * Retention >> + * Standalone Power Collapse (Standalone PC or SPC) >> + * Power Collapse (PC) >> + >> +WFI: WFI does a little more in addition to architectural clock gating. ARM > > This may be misleading. Call it PlatformWFI or something like that, not WFI if > that's not what it is. This gets at a little pet peeve of mine: IMO, naming any state with "WFI" is a bit confusing, because typically *every* idle state is entered by one (or more) CPU executing WFI, no? Kevin