• Hector Martin's avatar
    cpufreq: apple-soc: Add new driver to control Apple SoC CPU P-states · 6286bbb4
    Hector Martin authored
    This driver implements CPU frequency scaling for Apple Silicon SoCs,
    including M1 (t8103), M1 Max/Pro/Ultra (t600x), and M2 (t8112).
    
    Each CPU cluster has its own register set, and frequency management is
    fully automated by the hardware; the driver only has to write one
    register. There is boost frequency support, but the hardware will only
    allow their use if only a subset of cores in a cluster are in
    non-deep-idle. Since we don't support deep idle yet, these frequencies
    are not achievable, but the driver supports them. They will remain
    disabled in the device tree until deep idle is implemented, to avoid
    confusing users.
    
    This driver does not yet implement the memory controller performance
    state tuning that usually accompanies higher CPU p-states. This will be
    done in a future patch.
    Acked-by: default avatarMarc Zyngier <maz@kernel.org>
    Signed-off-by: default avatarHector Martin <marcan@marcan.st>
    Signed-off-by: default avatarViresh Kumar <viresh.kumar@linaro.org>
    6286bbb4
cpufreq-dt-platdev.c 5.94 KB