distro bootcmd: make net boot only optionally start USB
authorStephen Warren <swarren@nvidia.com>
Tue, 26 Jan 2016 18:10:12 +0000 (11:10 -0700)
committerSimon Glass <sjg@chromium.org>
Fri, 29 Jan 2016 04:01:23 +0000 (21:01 -0700)
commit3483b75d94716191b354d046b4ed3f322500a3ee
tree6978404ba1b3c484d875bbc64d8f34b1bf88319b
parente578b92cdb378df0f09065e3222fe8620867a57a
distro bootcmd: make net boot only optionally start USB

Currently, the distro boot commands always enumerate USB devices before
performing network operations. However, depending on the board and end-
user configuration, network devices may not be attached to USB, and so
enumerating USB may not be necessary. Enhance the scripts to make this
step optional, so that the user can decrease boot time if they don't
need USB.

This change is performed by moving the "usb start" invocation into a
standalone variable. If the user desires, they can replace that
variable's value with some no-op command such as "true" instead.

Booting from a USB storage device always needs to enumerate USB devices,
so this action is still hard-coded.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
doc/README.distro
include/config_distro_bootcmd.h