[PATCH v4 00/12] Krait clocks + Krait CPUfreq
Sricharan R
sricharan at codeaurora.org
Fri Dec 8 01:34:53 PST 2017
oops, got Mike's id wrong. Will just re-post fixing his id.
On 12/8/2017 2:59 PM, Sricharan R wrote:
> Mostly a resend of the v3 posted by Stephen quite some time back [1]
> except for few changes.
> Based on reading some feedback from list,
> * Dropped the patch "clk: Add safe switch hook" from v3 [2].
> Now this is taken care by patch#10 in this series only for Krait.
> * Dropped the path "clk: Avoid sending high rates to downstream
> clocks during set_rate" from v3 [3].
> * Rebased on top of clk-next.
> * Dropped the DT update from the series. Will send seperately
> * Now with cpufreq-dt+opp supporting voltage scaling, registering the
> krait cpu supplies in DT should be sufficient. But one issue is,
> the qcom-cpufreq drivers reads the efuse and based on that registers
> the opp data and then registers the cpufreq-dt device. So when
> cpufreq-dt driver probes and registers the regulator to the OPP framework,
> it expects that the opp data for the device should not be registered before
> the regulator. Will send a RFC patch removing that check, to find out the
> right way of doing it.
>
> These patches provide cpufreq scaling on devices with Krait CPUs.
> In Krait CPU designs there's one PLL and two muxes per CPU, allowing
> us to switch CPU frequencies independently.
>
> secondary
> +-----+ +
> | QSB |-------+------------|\
> +-----+ | | |-+
> | +-------|/ |
> | | + |
> +-----+ | | |
> | PLL |----+-------+ | primary
> +-----+ | | | +
> | | +-----|\ +------+
> +-------+ | | | \ | |
> | HFPLL |----------+-----------------| |-----| CPU0 |
> +-------+ | | | | | | |
> | | | +-----+ | / +------+
> | | +-| / 2 |---------|/
> | | +-----+ +
> | | secondary
> | | +
> | +------------|\
> | | |-+
> +---------------|/ | primary
> + | +
> +-----|\ +------+
> +-------+ | \ | |
> | HFPLL |----------------------------| |-----| CPU1 |
> +-------+ | | | | |
> | +-----+ | / +------+
> +-| / 2 |---------|/
> +-----+ +
>
> To support this in the common clock framework we model the muxes,
> dividers, and PLLs as different clocks. CPUfreq only interacts
> with the primary mux (farthest right in the diagram). When CPUfreq
> sets a rate, the mux code finds the best parent that can provide the rate.
> Due to the design, QSB and the top PLL are always a fixed rate and thus
> only support one frequency each. These sources provide the lowest
> frequencies for the CPUs. The HFPLLs are where we can make the CPU go
> faster (GHz range). Sometimes we need to run the HFPLL twice as
> fast and divide it by two to get a particular frequency.
>
> When switching rates we can't leave the CPU clocked by the HFPLL because
> we need to turn off the output of the PLL when changing its frequency.
> This means we have to switch over to the secondary mux and use one of the
> fixed sources. This is why we need something like the safe parent patch.
>
> [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/332607.html
> [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/332615.html
> [3] http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/332608.html
>
> Sricharan R (2):
> clk: qcom: Add safe switch hook for krait mux clocks
> cpufreq: dt: Reintroduce independent_clocks platform data
>
> Stephen Boyd (10):
> ARM: Add Krait L2 register accessor functions
> clk: mux: Split out register accessors for reuse
> clk: qcom: Add support for High-Frequency PLLs (HFPLLs)
> clk: qcom: Add HFPLL driver
> clk: qcom: Add MSM8960/APQ8064's HFPLLs
> clk: qcom: Add IPQ806X's HFPLLs
> clk: qcom: Add support for Krait clocks
> clk: qcom: Add KPSS ACC/GCC driver
> clk: qcom: Add Krait clock controller driver
> cpufreq: Add module to register cpufreq on Krait CPUs
>
> .../devicetree/bindings/arm/msm/qcom,kpss-acc.txt | 7 +
> .../devicetree/bindings/arm/msm/qcom,kpss-gcc.txt | 28 ++
> .../devicetree/bindings/arm/msm/qcom,pvs.txt | 38 ++
> .../devicetree/bindings/clock/qcom,hfpll.txt | 40 ++
> .../devicetree/bindings/clock/qcom,krait-cc.txt | 22 ++
> arch/arm/common/Kconfig | 3 +
> arch/arm/common/Makefile | 1 +
> arch/arm/common/krait-l2-accessors.c | 58 +++
> arch/arm/include/asm/krait-l2-accessors.h | 20 +
> drivers/clk/clk-mux.c | 75 ++--
> drivers/clk/qcom/Kconfig | 28 ++
> drivers/clk/qcom/Makefile | 5 +
> drivers/clk/qcom/clk-hfpll.c | 253 +++++++++++++
> drivers/clk/qcom/clk-hfpll.h | 54 +++
> drivers/clk/qcom/clk-krait.c | 136 +++++++
> drivers/clk/qcom/clk-krait.h | 51 +++
> drivers/clk/qcom/gcc-ipq806x.c | 82 +++++
> drivers/clk/qcom/gcc-msm8960.c | 172 +++++++++
> drivers/clk/qcom/hfpll.c | 106 ++++++
> drivers/clk/qcom/kpss-xcc.c | 96 +++++
> drivers/clk/qcom/krait-cc.c | 406 +++++++++++++++++++++
> drivers/cpufreq/Kconfig.arm | 9 +
> drivers/cpufreq/Makefile | 1 +
> drivers/cpufreq/cpufreq-dt.c | 7 +-
> drivers/cpufreq/cpufreq-dt.h | 6 +
> drivers/cpufreq/qcom-cpufreq.c | 204 +++++++++++
> include/dt-bindings/clock/qcom,gcc-msm8960.h | 2 +
> include/linux/clk-provider.h | 9 +-
> 28 files changed, 1888 insertions(+), 31 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt
> create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,pvs.txt
> create mode 100644 Documentation/devicetree/bindings/clock/qcom,hfpll.txt
> create mode 100644 Documentation/devicetree/bindings/clock/qcom,krait-cc.txt
> create mode 100644 arch/arm/common/krait-l2-accessors.c
> create mode 100644 arch/arm/include/asm/krait-l2-accessors.h
> create mode 100644 drivers/clk/qcom/clk-hfpll.c
> create mode 100644 drivers/clk/qcom/clk-hfpll.h
> create mode 100644 drivers/clk/qcom/clk-krait.c
> create mode 100644 drivers/clk/qcom/clk-krait.h
> create mode 100644 drivers/clk/qcom/hfpll.c
> create mode 100644 drivers/clk/qcom/kpss-xcc.c
> create mode 100644 drivers/clk/qcom/krait-cc.c
> create mode 100644 drivers/cpufreq/qcom-cpufreq.c
>
--
"QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
More information about the linux-arm-kernel
mailing list