Mike, are patches [3-5/5] in this revision fine by you? Rafael On Wednesday, August 24, 2011, MyungJoo Ham wrote: > The patchset revision v8 has minor updates since v7 and v6. > - Allow governors to have their own sysfs interface and init/exit callbacks. > > The patches 1/5 (OPP notifier) and 2/5 (DEVFREQ core) have no changes since v7. > There has been reordering between "add common sysfs interfaces" patch > and "add basic governors" (3/5 and 5/5) > "add internal interfaces for governors (4/5)" patch has been newly > introduced at v8 patchset. > > For a usage example, please look at > http://git.infradead.org/users/kmpark/linux-2.6-samsung/shortlog/refs/heads/devfreq > > In the above git tree, DVFS (dynamic voltage and frequency scaling) mechanism > is applied to the memory bus of Exynos4210 for Exynos4210-NURI boards. > In the example, the LPDDR2 DRAM frequency changes between 133, 266, and 400MHz > and other related clocks simply follow the determined DDR RAM clock. > > The DEVFREQ driver for Exynos4210 memory bus is at > /drivers/devfreq/exynos4210_memorybus.c in the git tree. > > In the dd (writing and reading 360MiB) test with NURI board, the memory > throughput was not changed (the performance is not deteriorated) while > the SoC power consumption has been reduced by 1%. When the memory access > is not that intense while the CPU is heavily used, the SoC power consumption > has been reduced by 6%. The power consumption has been compared with the > case using the conventional Exynos4210 CPUFREQ driver, which sets memory > bus frequency according to the CPU core frequency. Besides, when the CPU core > running slow and the memory access is intense, the performance (memory > throughput) has been increased by 11% (with higher SoC power consumption of > 5%). The tested governor is "simple-ondemand". > > MyungJoo Ham (5): > PM / OPP: Add OPP availability change notifier. > PM: Introduce DEVFREQ: generic DVFS framework with device-specific > OPPs > PM / DEVFREQ: add common sysfs interfaces > PM / DEVFREQ: add internal interfaces for governors > PM / DEVFREQ: add basic governors > > Documentation/ABI/testing/sysfs-devices-power | 46 +++ > drivers/Kconfig | 2 + > drivers/Makefile | 2 + > drivers/base/power/opp.c | 29 ++ > drivers/devfreq/Kconfig | 75 ++++ > drivers/devfreq/Makefile | 5 + > drivers/devfreq/devfreq.c | 463 +++++++++++++++++++++++++ > drivers/devfreq/governor.h | 20 + > drivers/devfreq/governor_performance.c | 24 ++ > drivers/devfreq/governor_powersave.c | 24 ++ > drivers/devfreq/governor_simpleondemand.c | 88 +++++ > drivers/devfreq/governor_userspace.c | 119 +++++++ > include/linux/devfreq.h | 150 ++++++++ > include/linux/opp.h | 12 + > 14 files changed, 1059 insertions(+), 0 deletions(-) > create mode 100644 drivers/devfreq/Kconfig > create mode 100644 drivers/devfreq/Makefile > create mode 100644 drivers/devfreq/devfreq.c > create mode 100644 drivers/devfreq/governor.h > create mode 100644 drivers/devfreq/governor_performance.c > create mode 100644 drivers/devfreq/governor_powersave.c > create mode 100644 drivers/devfreq/governor_simpleondemand.c > create mode 100644 drivers/devfreq/governor_userspace.c > create mode 100644 include/linux/devfreq.h > > _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
