Re: [PATCH v9 0/9] cpuidle driver for QCOM SoCs: 8064, 8074, 8084

[Lina Iyer <lina.iyer@linaro.org>]

Any comments, Daniel, Kevin, Stephen?

On Fri, Oct 24 2014 at 17:40 -0600, Lina Iyer wrote:
>Changes since v8:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg11473.html ]
>- Flatten out the file structure - merge pm.c into spm.c after discussions
>- Add a new function to set warm boot address, in scm-boot.c
>- Support for 8064 (New)
>- Tested on 8074, 8084. 8064 was tested with a WIP tree
>- Address review comments from v8
>- Looking into possiblility of  initializing the cpuidle device for a cpu,
>only when the corresponding spm device is probed successfully.
>
>Changes since v7:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg11199.html ]
>- Address review comments
>- Tested on 8974 but not 8084
>- WFI renamed to Standby
>- Update commit text with original author and link to the downstream tree
>
>Changes since v6:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg11012.html ]
>- SPM device nodes merged with existing SAW DT nodes
>- SPM register information is handled within the driver
>- Clean up from using 'msm' to 'qcom'
>        - Shorten some enumerations as well
>- Review comments from v6 addressed
>- New: Support for 8084 SoC
>        - Not tested. I do not have a board with this SoC, but the SPM
>        configuration should be identical for WFI and SPC
>
>Changes since v5:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg10559.html ]
>- Merge spm-devices.c and spm.c into one file and one patch
>        - Simplify implementation of the driver.
>        - Update documentation mapping the DT properties with corresponding
>          SPM register information.
>- Removed scm-boot changes for quad core warmboot, its has been pulled in.
>
>Changes since v4:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg10327.html ]
>- Update to the v8 of ARM generic idle states patches
>- Use platform device model for cpuidle-qcom
>- Clean up msm-pm.c to remove unnecessary include files and functions
>- Update commit text and documentation for all idle states
>- Remove scm-boot relocate patch from this series, submitted earlier
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg10518.html ]
>
>Changes since v3:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg10288.html ]
>- Fix CONFIG_QCOM_PM Kconfig as bool
>- More clean ups in spm.c and spm-devices.c
>        - Removed and re-organized data structures to make initialization simple
>        - Remove export of sequence flush functions
>        - Updated commit text
>        - Comments for use of barriers.
>- Rebase on top of 3.17-rc1
>
>Changes since v2:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg10148.html ]
>- Prune all the drivers to support basic WFI and power down cpuidle
>  functionality. Remove debug code.
>- Integrate KConfig changes into the drivers' patches.
>- Use Lorenzo's ARM idle-states patches as the basis for reading cpuidle
>  c-states from DT.
>  [ http://marc.info/?l=linux-pm&m=140794514812383&w=2 ]
>- Incorporate review comments
>- Rebase on top of 3.16
>
>Changes since v1/RFC:
>[ https://www.mail-archive.com/linux-arm-msm@vger.kernel.org/msg10065.html ]
>- Remove hotplug from the patch series. Will submit it separately.
>- Fix SPM drivers per the review comments
>- Modify patch sequence to compile SPM drivers independent of msm-pm, so as to
>  allow wfi() calls to use SPM even without SoC interface driver.
>
>8074/8084/8064 like any ARM SoC can do architectural clock gating, that helps save
>on power, but not enough of leakage power.  Leakage power of the SoC can be
>further reduced by turning off power to the core. To aid this, every core (cpu
>and L2) is accompanied by a Sub-system Power Manager (SPM), that can be
>configured to indicate the low power mode, the core would be put into and the
>SPM programs the peripheral h/w accordingly to enter low power and turn off the
>power rail to the core.
>
>The idle invocation hierarchy -
>
>CPUIDLE
>        |
>        cpuidle-qcom.c [CPUIdle driver]
>        |
>        ------> spm.c [SPM driver]
>                |
>                ------> scm-boot.c [SCM interface layer]
>                        |
>------------------------|--------------------------
>(EL)                    Secure Monitor Code
>                        |
>                        |
>                        wfi();
>------------------------|--------------------------
>(HW)                    [CPU] {clock gate}
>                        |
>                        -----> [SPM] {statemachine}
>
>
>The patchset does the following -
>
>- Introduce the SPM driver to control power to the core
>- Add device bindings for 8974, 8084, 8064 CPU SPM devices
>- Add cpuidle driver for QCOM cpus, using ARM generic idle state definitions.
>- Add device bindings for 8974, 8084, 8064 idle-states - WFI and SPC
>
>Thanks,
>Lina
>
>
>Lina Iyer (9):
>  qcom: scm: scm_set_warm_boot_addr() to set the warmboot address
>  qcom: spm: Add Subsystem Power Manager driver
>  arm: dts: qcom: Add power-controller device node for 8974 Krait CPUs
>  arm: dts: qcom: Add power-controller device node for 8084 Krait CPUs
>  arm: dts: qcom: Update power-controller device node for 8064 Krait
>    CPUs
>  qcom: cpuidle: Add cpuidle driver for QCOM cpus
>  arm: dts: qcom: Add idle states device nodes for 8974
>  arm: dts: qcom: Add idle states device nodes for 8084
>  arm: dts: qcom: Add idle state device nodes for 8064
>
> .../bindings/arm/msm/qcom,idle-state.txt           |  81 +++++
> .../devicetree/bindings/arm/msm/qcom,saw2.txt      |  31 +-
> arch/arm/boot/dts/qcom-apq8064.dtsi                |  37 ++-
> arch/arm/boot/dts/qcom-apq8084.dtsi                |  46 ++-
> arch/arm/boot/dts/qcom-msm8974.dtsi                |  46 ++-
> drivers/cpuidle/Kconfig.arm                        |   7 +
> drivers/cpuidle/Makefile                           |   1 +
> drivers/cpuidle/cpuidle-qcom.c                     |  72 +++++
> drivers/soc/qcom/Kconfig                           |   8 +
> drivers/soc/qcom/Makefile                          |   1 +
> drivers/soc/qcom/scm-boot.c                        |  22 ++
> drivers/soc/qcom/spm.c                             | 334 +++++++++++++++++++++
> include/soc/qcom/pm.h                              |  31 ++
> include/soc/qcom/scm-boot.h                        |   1 +
> 14 files changed, 702 insertions(+), 16 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,idle-state.txt
> create mode 100644 drivers/cpuidle/cpuidle-qcom.c
> create mode 100644 drivers/soc/qcom/spm.c
> create mode 100644 include/soc/qcom/pm.h
>
>-- 
>2.1.0
>