Messages in this thread | | | From | Nicolas Saenz Julienne <> | Subject | [PATCH 0/4] cpufreq support for the Raspberry Pi | Date | Tue, 4 Jun 2019 19:32:18 +0200 |
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Hi all, this series aims at adding cpufreq support to the Raspberry Pi family of boards.
The previous revision can be found at: https://lkml.org/lkml/2019/5/20/431
The series first factors out 'pllb' from clk-bcm2385 and creates a new clk driver that operates it over RPi's firmware interface[1]. We are forced to do so as the firmware 'owns' the pll and we're not allowed to change through the register interface directly as we might race with the over-temperature and under-voltage protections provided by the firmware.
Next it creates a minimal cpufreq driver that populates the CPU's opp table, and registers cpufreq-dt. Which is needed as the firmware controls the max and min frequencies available.
This was tested on a RPi3b+ and RPI2b which are the boards I have access to. Until this is tested broadly the cpufreq driver takes care of filtering out the rest of boards.
That's all, kind regards, Nicolas
[1] https://github.com/raspberrypi/firmware/wiki/Mailbox-property-interface
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Changes since RFC: - Addressed Viresh's comments in cpufreq driver - Addressed Stefan's comments in both cpufreq & clk drivers - Moved all firmware clk operations into it's own driver
Nicolas Saenz Julienne (4): clk: bcm2835: remove pllb clk: bcm283x: add driver interfacing with Raspberry Pi's firmware clk: bcm2835: register Raspberry Pi's firmware clk device cpufreq: add driver for Raspbery Pi
drivers/clk/bcm/Makefile | 1 + drivers/clk/bcm/clk-bcm2835.c | 40 ++-- drivers/clk/bcm/clk-raspberrypi.c | 316 ++++++++++++++++++++++++++ drivers/cpufreq/Kconfig.arm | 8 + drivers/cpufreq/Makefile | 1 + drivers/cpufreq/raspberrypi-cpufreq.c | 84 +++++++ 6 files changed, 423 insertions(+), 27 deletions(-) create mode 100644 drivers/clk/bcm/clk-raspberrypi.c create mode 100644 drivers/cpufreq/raspberrypi-cpufreq.c
-- 2.21.0
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