It was recently observed that one of the worst offenders for system startup delays was the amd_pmc driver. With 5.18-rc1 and measured with ftrace amd_pmc_probe spends about 116ms. This is bonkers for what the init actually does. As a lot of the functionality that is slowing down startup is related to debugging mechanisms or conditional code that is executed during suspend, move it out of init. This speeds up the startup to happen in ~1ms. This is done at the expense that the first suspend or first time debug features are accessed it will be slower. Those aren't critical path for a user turning on the machine though, so this is a reasonable tradeoff. Mario Limonciello (3): platform/x86: amd-pmc: Move SMU logging setup out of init platform/x86: amd-pmc: Move FCH init to first use platform/x86: amd-pmc: Avoid reading SMU version at probe time drivers/platform/x86/amd-pmc.c | 85 +++++++++++++++++++++------------- 1 file changed, 54 insertions(+), 31 deletions(-) -- 2.34.1
