This patch changes several cache-related pieces to be cleaner, faster or
more correct. The largest point is removing the old
arm_invalidate_caches() function and surrounding bootblock code to
initialize SCTLR and replace it with an all-assembly function that takes
care of cache and SCTLR initialization to bring the system to a known
state. It runs without stack and before coreboot makes any write
accesses to be as compatible as possible with whatever state the system
was left in by preceeding code. This also finally fixes the dreaded
icache bug that wasted hundreds of milliseconds during boot.
CQ-DEPEND=CL:183877
BUG=None
TEST=Snow and Nyan still boot. Time between entering romstage main() and
the configure_l2ctlr() call on Nyan drops from 390ms to 0.3ms. Even with
icache turned on the old implementation took 7.8ms since it cleared the
cache multiple times with a slow algorithm.
Change-Id: I7bb4995af8184f6383f8e3b1b870b0662bde8bd4
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/183890
07a35925dc