The Adaptive Supply Voltage (ASV) on Exynos SoCs is a technique of adjusting subsystem operating points, i.e. power supply voltage for given clock frequency, in order to better match actual capabilities of the hardware and optimize power consumption. This applies to subsystems of the SoC like: CPU clusters, GPU, the memory controller or camera ISP. During production process the SoC chip is assigned to one of several bins (ASV groups) and the group information is encoded in the SoC CHIPID block registers and/or OTP memory. This information is then used to select more finely matching operating points for devices. The motivation of this patch set was, amongst others, to ensure proper Odroid XU3/XU4 operation with highest performance operating points. This patch set adds a driver parsing ASV tables from DT and finely adjusting CPU operating points to optimize power consumption and ensure proper operation for each SoC revision. I just recently noticed there are already somewhat similar drivers located in drivers/power/avs, I'm considering moving exynos-asv driver there in next iteration of this patch set. This patch set includes Exynos CHIPID driver posted by Pankaj Dubey and futher improved by Bartlomiej Zolnierkiewicz [1]. Tested on Odroid XU3, XU3 Lite, XU4 and Exynos5433 TM2 board (with further patches not included in this series). The DT binding documented in patch 3/8 doesn't describe any hardware, it's purely software description. I'd like to get some feedback specially on that one, I thought it was reasonable to put that data in DT. There will be many of this tables, per each SoC type and the driver looks much better with those tables in DT IMHO. [1] https://lkml.org/lkml/2018/11/15/908 Pankaj Dubey (3): soc: samsung: Add exynos chipid driver support ARM: EXYNOS: enable exynos_chipid for ARCH_EXYNOS ARM64: EXYNOS: enable exynos_chipid for ARCH_EXYNOS Sylwester Nawrocki (5): soc: samsung: Exynos chipid driver update dt-bindings: exynos: Add ASV tables binding documentation soc: samsung: Add Exynos Adaptive Supply Voltage driver ARM: EXYNOS: Enable exynos-asv driver for ARCH_EXYNOS ARM: dts: exynos: Add ASV tables for exynos5422/5800 .../devicetree/bindings/arm/samsung/asv.txt | 76 +++++ arch/arm/boot/dts/exynos5.dtsi | 2 +- arch/arm/boot/dts/exynos5800.dtsi | 207 +++++++++++++ arch/arm/mach-exynos/Kconfig | 2 + arch/arm64/Kconfig.platforms | 1 + drivers/soc/samsung/Kconfig | 16 + drivers/soc/samsung/Makefile | 5 + drivers/soc/samsung/exynos-asv.c | 279 ++++++++++++++++++ drivers/soc/samsung/exynos-asv.h | 114 +++++++ drivers/soc/samsung/exynos-chipid.c | 113 +++++++ drivers/soc/samsung/exynos-chipid.h | 48 +++ drivers/soc/samsung/exynos5422-asv.c | 209 +++++++++++++ drivers/soc/samsung/exynos5422-asv.h | 25 ++ 13 files changed, 1096 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/arm/samsung/asv.txt create mode 100644 drivers/soc/samsung/exynos-asv.c create mode 100644 drivers/soc/samsung/exynos-asv.h create mode 100644 drivers/soc/samsung/exynos-chipid.c create mode 100644 drivers/soc/samsung/exynos-chipid.h create mode 100644 drivers/soc/samsung/exynos5422-asv.c create mode 100644 drivers/soc/samsung/exynos5422-asv.h -- 2.17.1
