libpayload: Add mock architecture

Mock architecture can be used to build libpayload using host compiler.
It can be enabled by setting ARCH_MOCK=y in the dotconfig. It sets
LITTLE_ENDIAN=y, as most machines these days use little-endian CPUs.
Libpayload will use HOSTCC as CC, HOSTLD as LD, etc. instead of tools
provided by xcompile.
Mock architecture configuration can be used by payloads for testing
purposes. Thanks to it, tests can be architecture-independent,
and can be executed without requiring compatible Kconfig options,
e.g. ARCH_ARM64=y for ARM64 machine. However, one has to provide
implementation for most architecture-specific functions present
in arch/* directories.

Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Change-Id: Ie3a6e6f6cad2f8a2e48a8e546d3b79c577653080
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57708
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

1 files changed, 18 insertions, 0 deletions

diff --git a/payloads/libpayload/include/mock/arch/cache.h b/payloads/libpayload/include/mock/arch/cache.h
new file mode 100644
index 0000000000..1e71d5e0e2
--- /dev/null
+++ b/payloads/libpayload/include/mock/arch/cache.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef __ARCH_CACHE_H__
+#define __ARCH_CACHE_H__
+
+/* No support for cache in the mock architecture */
+
+#define dmb()
+#define dsb()
+#define dcache_clean_all()
+#define dcache_clean_by_mva(addr, len)
+#define dcache_invalidate_all()
+#define dcache_invalidate_by_mva(addr, len)
+#define dcache_clean_invalidate_all()
+#define dcache_clean_invalidate_by_mva(addr, len)
+#define cache_sync_instructions()
+
+#endif /* __ARCH_CACHE_H__ */