The following patchset enables CPU frequency scaling support on the QCS404 (with dynamic voltage scaling). It is important to notice that this functionality will be superseded by Core Power Reduction (CPR), a more accurate form of AVS found on certain Qualcomm SoCs. Some of the changes required to support CPR do conflict with the configuration required for CPUFreq. In particular, the following commit for CPR - already merged - will need to be reverted in order to enable CPUFreq. Author: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@xxxxxxxxxx> Date: Thu Jul 25 12:41:36 2019 +0200 cpufreq: Add qcs404 to cpufreq-dt-platdev blacklist Patch 8 "clk: qcom: hfpll: CLK_IGNORE_UNUSED" is a bit controversial; in this platform, this PLL provides the clock signal to a CPU core. But in others it might not. We opted for the minimal ammount of changes without affecting the default functionality: simply bypassing the COMMON_CLK_DISABLE_UNUSED framework and letting the firwmare chose whether to enable or disable the clock at boot. However maybe a DT property and marking the clock as critical would be more appropriate for this PLL. we'd appreciate the maintainer's input on this topic. v2: - dts: ms8916: apcs mux/divider: new bindings (the driver can still support the old bindings) - qcs404.dtsi fix apcs-hfpll definition fix cpu_opp_table definition - GPLL0_AO_OUT operating frequency define new alpha_pll_fixed_ops to limit the operating frequency v3: - qcom-apcs-ipc-mailbox replace goto to ease readability - apcs-msm8916.c rework patch to use of_clk_parent_fill - hfpll.c add relevant comments to the code - qcs404.dtsi add voltage scaling support v4: - squash OPP definition and DVFS enablement in dts (patches 10 and 13 in previous version) - qcom-apcs-ipc-mailbox replace return condition for readability - answer one question on CLK_IGNORE_UNUSED in mailing list Jorge Ramirez-Ortiz, Niklas Cassel (13): clk: qcom: gcc: limit GPLL0_AO_OUT operating frequency mbox: qcom: add APCS child device for QCS404 mbox: qcom: replace integer with valid macro dt-bindings: mailbox: qcom: Add clock-name optional property clk: qcom: apcs-msm8916: get parent clock names from DT clk: qcom: hfpll: get parent clock names from DT clk: qcom: hfpll: register as clock provider clk: qcom: hfpll: CLK_IGNORE_UNUSED arm64: dts: qcom: msm8916: Add the clocks for the APCS mux/divider arm64: dts: qcom: qcs404: Add HFPLL node arm64: dts: qcom: qcs404: Add the clocks for APCS mux/divider arm64: dts: qcom: qcs404: Add DVFS support arm64: defconfig: Enable HFPLL .../mailbox/qcom,apcs-kpss-global.txt | 24 +++++++++-- arch/arm64/boot/dts/qcom/msm8916.dtsi | 3 +- arch/arm64/boot/dts/qcom/qcs404.dtsi | 43 +++++++++++++++++++ arch/arm64/configs/defconfig | 1 + drivers/clk/qcom/apcs-msm8916.c | 23 ++++++++-- drivers/clk/qcom/clk-alpha-pll.c | 8 ++++ drivers/clk/qcom/clk-alpha-pll.h | 1 + drivers/clk/qcom/gcc-qcs404.c | 2 +- drivers/clk/qcom/hfpll.c | 25 ++++++++++- drivers/mailbox/qcom-apcs-ipc-mailbox.c | 11 +++-- 10 files changed, 128 insertions(+), 13 deletions(-) -- 2.22.0