mb/google/poppy/variant/nami - Ensure power cycle of FPMCU on startup

Add functionality to ensure that the FPMCU is power cycled long enough
on boot to ensure proper reset.

This solution relies solely on coreboot to sequence the power and reset
signals appropriately (150ms on boot).

-Confirmed power is off for 150ms on boot.
-Confirmed RCC_CSR of FPMCU indicates power cycle occurred.
-Confirmed reset is de-asserted approx 3ms after power application
(target >2.5ms)


BUG=b:245954151
TEST=Confirmed FPMCU is still functional on Nami and timings are
as expected.

Change-Id: I0a23bda96bc2ea90be81a2310605f75c55c0a839
Signed-off-by: Tarun Tuli <taruntuli@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/73212
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Shelley Chen <shchen@google.com>
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>

0 files changed, 0 insertions, 0 deletions