This patch discards all the used entropy bits from the global memory
pool after being delivered to the requester (lower exception levels) by
overwriting them with zeroes.
It effectively implements the requirement, as part of TRNG FW interface
listed at DEN0098 (section 1.2).
https://developer.arm.com/documentation/den0098/latest
Change-Id: I447cbccc1a8ad972418a3569c99f010189d4b2f6
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
This patch adds the following changes to complete the existing
TRNG implementation:
1. Adds a feature specific scope for buildlog generation.
2. Updates the docs on the build flag "TRNG_SUPPORT" and its values.
3. Makefile update and improves the existing comments at few sections
for better understanding of the underlying logic.
Change-Id: I3f72f0ccd5c94005a2df87158cf23199d2160d37
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
This adds the TRNG Firmware Interface Service to the standard
service dispatcher. This includes a method for dispatching entropy
requests to platforms and includes an entropy pool implementation to
avoid dropping any entropy requested from the platform.
Change-Id: I71cadb3cb377a507652eca9e0d68714c973026e9
Signed-off-by: Jimmy Brisson <jimmy.brisson@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>