This series adds upstream DRAM and interconnect scaling support for imx8m series chips. It uses a per-SOC interconnect provider layered on top of multiple instances of devfreq for scalable nodes along the interconnect. Existing qcom interconnect providers mostly translate bandwidth requests into firmware calls but equivalent firmware on imx8m is much thinner. Scaling support for individual nodes (NIC/NOC and DDRC) is implemented through devfreq. The imx interconnect provider doesn't communicate with devfreq instance directly but rather computes "minimum frequencies" for nodes along the path and creates dev_pm_qos requests. This needs core changes for dev_pm_qos frequency support for devfreq: https://patchwork.kernel.org/project/linux-arm-kernel/list/?series=196443 Since imx interconnect only needs to interact with imx devfreq it would also be possible to tie them together directly, but it would be a little sad. Since there is no single devicetree node that can represent the "interconnect" the main NOC is picked as the "interconnect provider" and will probe the interconnect platform device if #interconnect-cells is present. This is a bit odd. On i.MX there are multiple instances of a few interconnect IPs, this patch identifies them by enumerating the entire devicetree scanning for the "interconnect-node-id" property. As far as I see current providers do this based entirely on compatible string of the interconnect instance and this seems very odd to me. Do you think we could move this "interconnect-node-id" approach to core interconnect bindings? The same interconnect-node-id property is used to identify the DDRC and this is arguably a hack. Also as a github branch (with few other changes): https://github.com/cdleonard/linux/tree/next_imx_busfreq This is layered upon imx-ddrc scaling support: * https://patchwork.kernel.org/project/linux-arm-kernel/list/?series=196459 The DDRC only really interacts by receiving dev_pm_qos requests. Changes since RFCv4: * Drop icc proxy nonsense * Make devfreq driver for NOC probe the ICC driver if #interconnect-cells is present. * Move NOC support to interconnect series and rename the node in DT * Add support for all chips at once, differences are not intereseting and there is more community interest for 8mq than 8mm. Link: https://patchwork.kernel.org/cover/11111865/ Changes since RFCv3: * Remove the virtual "icc" node and add devfreq nodes as proxy providers * Fix build on 32-bit arm (reported by kbuilt test robot) * Remove ARCH_MXC_ARM64 (never existed in upstream) * Remove _numlinks, calculate instead * Replace __BUSFREQ_H header guard * Improve commit message and comment spelling * Fix checkpatch issues Link to RFCv3: https://patchwork.kernel.org/cover/11078671/ Changes since RFCv2 and initial work by Alexandre Bailon: * Relying on devfreq and dev_pm_qos instead of CLK * No more "platform opp" stuff * No more special suspend handling: use suspend-opp on devfreq instead. * Replace all mentions of "busfreq" with "interconnect" Link to v2: https://patchwork.kernel.org/patch/11056789/ Leonard Crestez (10): dt-bindings: devfreq: Add bindings for generic imx buses PM / devfreq: Add generic imx bus driver PM / devfreq: imx: Register interconnect device PM / devfreq: Add devfreq_get_devfreq_by_node interconnect: Add imx core driver interconnect: imx: Add platform driver for imx8mm interconnect: imx: Add platform driver for imx8mq interconnect: imx: Add platform driver for imx8mn arm64: dts: imx8m: Add NOC nodes arm64: dts: imx8m: Add interconnect provider properties .../devicetree/bindings/devfreq/imx.yaml | 83 ++++++ arch/arm64/boot/dts/freescale/imx8mm.dtsi | 26 ++ arch/arm64/boot/dts/freescale/imx8mn.dtsi | 26 ++ arch/arm64/boot/dts/freescale/imx8mq.dtsi | 26 ++ drivers/devfreq/Kconfig | 12 + drivers/devfreq/Makefile | 1 + drivers/devfreq/devfreq.c | 42 ++- drivers/devfreq/imx-devfreq.c | 185 ++++++++++++ drivers/interconnect/Kconfig | 1 + drivers/interconnect/Makefile | 1 + drivers/interconnect/imx/Kconfig | 17 ++ drivers/interconnect/imx/Makefile | 4 + drivers/interconnect/imx/imx.c | 273 ++++++++++++++++++ drivers/interconnect/imx/imx.h | 60 ++++ drivers/interconnect/imx/imx8mm.c | 105 +++++++ drivers/interconnect/imx/imx8mn.c | 94 ++++++ drivers/interconnect/imx/imx8mq.c | 103 +++++++ include/dt-bindings/interconnect/imx8mm.h | 49 ++++ include/dt-bindings/interconnect/imx8mn.h | 41 +++ include/dt-bindings/interconnect/imx8mq.h | 48 +++ include/linux/devfreq.h | 1 + 21 files changed, 1187 insertions(+), 11 deletions(-) create mode 100644 Documentation/devicetree/bindings/devfreq/imx.yaml create mode 100644 drivers/devfreq/imx-devfreq.c create mode 100644 drivers/interconnect/imx/Kconfig create mode 100644 drivers/interconnect/imx/Makefile create mode 100644 drivers/interconnect/imx/imx.c create mode 100644 drivers/interconnect/imx/imx.h create mode 100644 drivers/interconnect/imx/imx8mm.c create mode 100644 drivers/interconnect/imx/imx8mn.c create mode 100644 drivers/interconnect/imx/imx8mq.c create mode 100644 include/dt-bindings/interconnect/imx8mm.h create mode 100644 include/dt-bindings/interconnect/imx8mn.h create mode 100644 include/dt-bindings/interconnect/imx8mq.h -- 2.17.1
