From mboxrd@z Thu Jan 1 00:00:00 1970 From: jean.pihet@newoldbits.com Subject: [PATCH v2 00/11] PM QoS: add a per-device wake-up latency constraint class Date: Thu, 30 Jun 2011 17:11:14 +0200 Message-ID: <1309446685-17502-1-git-send-email-j-pihet__5944.12226132608$1309447050$gmane$org@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" , Paul Walmsley , Kevin Hilman , Magnus Damm , Linux PM mailing list Cc: Jean Pihet List-Id: linux-pm@vger.kernel.org From: Jean Pihet This patch set is in an RFC state, for review and comments. In order to implement the new class in PM QoS the following changes have been made: 1. Add a new PM QoS class for device wake-up constraints (PM_QOS_DEV_WAKEUP_LATENCY). Due to the per-device nature of the new class the constraints lists are stored inside the device dev_pm_info struct instead of the internal per-class constraints lists. The new class is only available from kernel drivers and so is not exported to user space. 2. Added a notification of device insertion/removal from the device PM framework to PM QoS. This allows to init/de-init the per-device constraints list upon device insertion and removal. RFC state for comments and review, barely tested 3. Make the pm_qos_add_request API more generic by using a struct pm_qos_parameters parameter. This allows easy extension in the future. 4. Upon a change of the strongest constraint in the PM_QOS_DEV_WAKEUP_LATENCY class a notification chain mechanism is used to take action on the system. This is the proposed way to have PM QoS and the platform dependant code to interact with each other, cf. 4 below. The notification mechanism now passes the constraint request struct ptr in order for the notifier callback to have access to the full set of constraint data, e.g. the struct device ptr. 5. cpuidle interaction with the OMAP3 cpuidle handler Since cpuidle is a CPU centric framework it decides the MPU next power state based on the MPU exit_latency and target_residency figures. The rest of the power domains get their next power state programmed from the PM_QOS_DEV_WAKEUP_LATENCY class of the PM QoS framework, via the device wake-up latency constraints. Note: the exit_latency and target_residency figures of the MPU include the MPU itself and the peripherals needed for the MPU to execute instructions (e.g. main memory, caches, IRQ controller, MMU etc). Some of those peripherals can belong to other power domains than the MPU subsystem and so the corresponding latencies must be included in those figures. 6. Update the pm_qos_add_request callers to the generic API 7. Minor clean-ups and rename of struct fields Questions: 1. How to retrieve the device ptr from a given device driver in order to add a constraint on it? 2. The device struct has recently been extended with the power domain information. Can this be used to apply the constraints on power domains? On-going developments, patches in preparation: 1. write Documentation for the new PM QoS class 2. validate the constraints framework on OMAP4 HW (done on OMAP3) 3. refine the power domains wake-up latency and the cpuidle figures Based on the master branch of the linux-omap git tree (3.0.0-rc3). Compile tested using OMAP and x86 generic defconfigs. Tested on OMAP3 Beagleboard (ES2.x) with full RETention and OFF modes. Changelog: v2: . Rework after comments on the mailing lists . Added a notification of device insertion/removal from the device PM framework . Validated on OMAP3 HW Jean Pihet (10): PM: add a per-device wake-up latency constraints plist PM: extend PM QoS with per-device wake-up constraints PM QoS: support the dynamic devices insertion and removal OMAP PM: create a PM layer plugin for per-device constraints OMAP PM: early init of the pwrdms states OMAP2+: powerdomain: control power domains next state OMAP3: powerdomain data: add wake-up latency figures OMAP2+: omap_hwmod: manage the wake-up latency constraints OMAP: PM CONSTRAINTS: implement the devices wake-up latency constraints OMAP2+: cpuidle only influences the MPU state Vishwanath BS (1): OMAP4: powerdomain data: add wake-up latency figures arch/arm/mach-omap2/cpuidle34xx.c | 42 +--- arch/arm/mach-omap2/omap_hwmod.c | 26 ++- arch/arm/mach-omap2/pm.h | 17 ++- arch/arm/mach-omap2/pm34xx.c | 2 +- arch/arm/mach-omap2/pm44xx.c | 2 +- arch/arm/mach-omap2/powerdomain.c | 190 ++++++++++++++ arch/arm/mach-omap2/powerdomain.h | 33 +++- arch/arm/mach-omap2/powerdomains3xxx_data.c | 77 ++++++ arch/arm/mach-omap2/powerdomains44xx_data.c | 85 +++++++ arch/arm/plat-omap/Kconfig | 7 + arch/arm/plat-omap/Makefile | 1 + arch/arm/plat-omap/i2c.c | 20 -- arch/arm/plat-omap/include/plat/omap-pm.h | 128 ---------- arch/arm/plat-omap/include/plat/omap_hwmod.h | 2 + arch/arm/plat-omap/omap-pm-constraints.c | 344 ++++++++++++++++++++++++++ arch/arm/plat-omap/omap-pm-noop.c | 89 ------- drivers/base/power/main.c | 5 + drivers/i2c/busses/i2c-omap.c | 35 ++- drivers/media/video/via-camera.c | 5 +- drivers/net/e1000e/netdev.c | 9 +- drivers/net/wireless/ipw2x00/ipw2100.c | 6 +- include/linux/pm.h | 3 + include/linux/pm_qos_params.h | 42 ++-- kernel/pm_qos_params.c | 231 ++++++++++++------ sound/core/pcm_native.c | 8 +- 25 files changed, 1023 insertions(+), 386 deletions(-) create mode 100644 arch/arm/plat-omap/omap-pm-constraints.c -- 1.7.4.1