8c98644bfc
Turning on initcall debug on one system showed this: initcall sdhci_msm_driver_init+0x0/0x28 returned 0 after 34782 usecs The lion's share of this time (~33 ms) was in mmc_power_up(). This shouldn't be terribly surprising since there are a few calls to delay based on "power_delay_ms" and the default delay there is 10 ms. Because we haven't specified that we'd prefer asynchronous probe for this driver then we'll wait for this driver to finish before we start probes for more drivers. While 33 ms doesn't sound like tons, every little bit counts. There should be little problem with turning on asynchronous probe for this driver. It's already possible that previous drivers may have turned on asynchronous probe so we might already have other things (that probed before us) probing at the same time we are anyway. This driver isn't really providing resources (clocks, regulators, etc) that other drivers need to probe and even if it was they should be handling -EPROBE_DEFER. Let's turn this on and get a bit of boot speed back. Signed-off-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20200902164303.1.I5e598a25222b4534c0083b61dbfa4e0e76f66171@changeid Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.