mirror of
https://github.com/Telecominfraproject/OpenCellular.git
synced 2026-01-10 17:41:54 +00:00
c5b90d7e77
First implementation of a low power idle task for the LM4 chip. The low power mode is selected by defining CONFIG_LOW_POWER_IDLE in a board.h file. This commit turns it on for Peppy, Slippy, and Falco only because those are the only boards tested. When using the low power idle task, the chip goes in to deep sleep when it can. Deep sleep disables clocks to most peripherals and puts the onboard flash and RAM into a low power mode. The chip is woken out of deep sleep using the RTC in the hibernate module. Increased the idle task stack size to handle more involved idle task. In board.c, the array of GPIO info can be used to select which GPIO points can wake up the EC from deep sleep. Currenlty selected are the power button, lid open, AC present, PCH_SLP_S3, and PCH_SLP_S5. Additionally the port with the KB scan row GPIO point is also enabled to wake up the EC from deep sleep. Signed-off-by: Alec Berg <alecaberg@chromium.org> BUG=None BRANCH=none TEST=Passes all unit tests. Runs on slippy, peppy, and falco with no noticeable side affects. Verified that the power consumed by the EC is lower when in S3, S5 and G3 by scoping the sense resistor powering the chip. Change-Id: I83fa9a159a4b79201b99f2c32678dc4fc8921726 Reviewed-on: https://chromium-review.googlesource.com/172183 Reviewed-by: Vincent Palatin <vpalatin@chromium.org> Reviewed-by: Randall Spangler <rspangler@chromium.org> Commit-Queue: Alec Berg <alecaberg@chromium.org> Tested-by: Alec Berg <alecaberg@chromium.org>
In the most general case, the flash layout looks something like this: +---------------------+ | Reserved for EC use | +---------------------+ +---------------------+ | Vblock B | +---------------------+ | RW firmware B | +---------------------+ +---------------------+ | Vblock A | +---------------------+ | RW firmware A | +---------------------+ +---------------------+ | FMAP | +---------------------+ | Public root key | +---------------------+ | Read-only firmware | +---------------------+ BIOS firmware (and kernel) put the vblock info at the start of each image where it's easy to find. The Blizzard EC expects the firmware vector table to come first, so we have to put the vblock at the end. This means we have to know where to look for it, but that's built into the FMAP and the RO firmware anyway, so that's not an issue. The RO firmware doesn't need a vblock of course, but it does need some reserved space for vboot-related things. Using SHA256/RSA4096, the vblock is 2468 bytes (0x9a4), while the public root key is 1064 bytes (0x428) and the current FMAP is 644 bytes (0x284). If we reserve 4K at the top of each FW image, that should give us plenty of room for vboot-related stuff.