Crash reporting via the default consoles registered by MULTI_CONSOLE_API
has been broken since commit d35cc34 (Console: Use callee-saved
registers), which was introduced to allow console drivers written in C.
It's not really possible with the current crash reporting framework to
support console drivers in C, however we should make sure that the
existing assembly drivers that do support crash reporting continue to
work through the MULTI_CONSOLE_API.
This patch fixes the problem by creating custom console_putc() and
console_flush() implementations for the crash reporting case that do not
use the stack. Platforms that want to use this feature will have to link
plat/common/aarch64/crash_console_helpers.S explicitly.
Also update the documentation to better reflect the new reality (of this
being an option rather than the expected default for most platforms).
Change-Id: Id0c761e5e2fddaf25c277bc7b8ab603946ca73cb
Signed-off-by: Julius Werner <jwerner@chromium.org>
Commit e74afb652 (Deprecate weak crash console functions) deprecated the
default inclusion of weak definitions for plat_crash_console functions
in plat/common/aarch64/platform_helpers.S. The code was later copied out
to plat/common/aarch64/crash_console_helpers.S so platforms can link it
explicitly if they want to. However, since deprecation does not mean
removal, the same code is also still duplicated in platform_helpers.S.
The duplicated code contains both empty stubs for the !MULTI_CONSOLE_API
case, and a real implementation that used to work but was broken by
commit d35cc34 (Console: Use callee-saved registers) for
MULTI_CONSOLE_API. It's not great to have both of these duplicated in
two files, so this patch splits them up: in platform_helpers.S we'll
only keep the empty stubs (guarded by !ERROR_DEPRECATED), which should
not regress functionality since the MULTI_CONSOLE_API implementation was
already broken anyway. In crash_console_helpers.S, we'll only keep the
MULTI_CONSOLE_API version, which is enough both as an implementation in
itself and as a sample for how to reimplement these functions in a
platform-specific file.
Change-Id: I83d95a90ab6aac597dc2ea2f2797ac2c8ed075d4
Signed-off-by: Julius Werner <jwerner@chromium.org>
Platforms that wish to use the sample functions have to add the file to
their Makefile. It is not included by default.
Change-Id: I713617bb58dc218967199248f68da86241d7ec40
Signed-off-by: Antonio Nino Diaz <antonio.ninodiaz@arm.com>
Julius Werner
Antonio Nino Diaz