The following patchset adds interconnect[1][2] framework support to the exynos-bus devfreq driver. Extending the devfreq driver with interconnect functionality started as a response to the issue referenced in [3]. The patches can be subdivided into three groups: (a) Tweaking the interconnect framework to support the exynos-bus use case (patches 01--03/07). Exporting of_icc_get_from_provider() allows to avoid hardcoding every single graph edge in the DT or driver source, and relaxing the requirement on #interconnect-cells removes the need to provide dummy node IDs in the DT. A new field in struct icc_provider is used to explicitly allow configuring node pairs from two different providers. (b) Implementing interconnect providers in the exynos-bus devfreq driver and adding required DT properties for one selected platform, namely Exynos4412 (patches 04--05/07). Due to the fact that this aims to be a generic driver for various Exynos SoCs, node IDs are generated dynamically (rather than hardcoded). (c) Implementing a sample interconnect consumer for exynos-mixer targeted at solving the issue referenced in [3], again with DT properties only for Exynos4412 (patches 06--07/07). Integration of devfreq and interconnect frameworks is achieved by using the dev_pm_qos_*() API. When CONFIG_INTERCONNECT is 'n' (such as in exynos_defconfig) all interconnect API functions are no-ops. This series depends on these three patches (merged into devfreq-next[6]): * https://patchwork.kernel.org/patch/11279087/ * https://patchwork.kernel.org/patch/11279093/ * https://patchwork.kernel.org/patch/11293765/ and on this series: * https://patchwork.kernel.org/cover/11304545/ (which does not apply cleanly on next-20191220, adding --exclude=arch/arm/boot/dts/exynos5422-odroid-core.dtsi to 'git am' is a quick workaround) --- Changes since v2 [5]: * Use icc_std_aggregate(). * Implement a different modification of apply_constraints() in drivers/interconnect/core.c (patch 03). * Use 'exynos,interconnect-parent-node' in the DT instead of 'devfreq'/'parent', depending on the bus. * Rebase on DT patches that deprecate the 'devfreq' DT property. * Improve error handling, including freeing generated IDs on failure. * Remove exynos_bus_icc_connect() and add exynos_bus_icc_get_parent(). --- Changes since v1 [4]: * Rebase on coupled regulators patches. * Use dev_pm_qos_*() API instead of overriding frequency in exynos_bus_target(). * Use IDR for node ID allocation. * Reverse order of multiplication and division in mixer_set_memory_bandwidth() (patch 07) to avoid integer overflow. --- Artur Świgoń Samsung R&D Institute Poland Samsung Electronics --- References: [1] Documentation/interconnect/interconnect.rst [2] Documentation/devicetree/bindings/interconnect/interconnect.txt [3] https://patchwork.kernel.org/patch/10861757/ (original issue) [4] https://patchwork.kernel.org/cover/11054417/ (v1 of this RFC) [5] https://patchwork.kernel.org/cover/11152595/ (v2 of this RFC) [6] https://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/linux.git/log/?h=devfreq-next Artur Świgoń (6): interconnect: Export of_icc_get_from_provider() interconnect: Relax requirement in of_icc_get_from_provider() interconnect: Allow inter-provider pairs to be configured arm: dts: exynos: Add interconnect bindings for Exynos4412 devfreq: exynos-bus: Add interconnect functionality to exynos-bus arm: dts: exynos: Add interconnects to Exynos4412 mixer Marek Szyprowski (1): drm: exynos: mixer: Add interconnect support .../boot/dts/exynos4412-odroid-common.dtsi | 5 + arch/arm/boot/dts/exynos4412.dtsi | 1 + drivers/devfreq/exynos-bus.c | 144 ++++++++++++++++++ drivers/gpu/drm/exynos/exynos_mixer.c | 71 ++++++++- drivers/interconnect/core.c | 16 +- include/linux/interconnect-provider.h | 8 + 6 files changed, 232 insertions(+), 13 deletions(-) -- 2.17.1
