kernel_optimize_test/arch/mips/Makefile.postlink
Paul Burton e4acfbc18f
MIPS: Check Loongson3 LL/SC errata workaround correctness
When Loongson3 LL/SC errata workarounds are enabled (ie.
CONFIG_CPU_LOONGSON3_WORKAROUNDS=y) run a tool to scan through the
compiled kernel & ensure that the workaround is applied correctly. That
is, ensure that:

  - Every LL or LLD instruction is preceded by a sync instruction.

  - Any branches from within an LL/SC loop to outside of that loop
    target a sync instruction.

Reasoning for these conditions can be found by reading the comment above
the definition of __SYNC_loongson3_war in arch/mips/include/asm/sync.h.

This tool will help ensure that we don't inadvertently introduce code
paths that miss the required workarounds.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: linux-kernel@vger.kernel.org
2019-10-07 09:43:13 -07:00

45 lines
962 B
Makefile

# SPDX-License-Identifier: GPL-2.0
# ===========================================================================
# Post-link MIPS pass
# ===========================================================================
#
# 1. Check that Loongson3 LL/SC workarounds are applied correctly
# 2. Insert relocations into vmlinux
PHONY := __archpost
__archpost:
-include include/config/auto.conf
include scripts/Kbuild.include
CMD_LS3_LLSC = arch/mips/tools/loongson3-llsc-check
quiet_cmd_ls3_llsc = LLSCCHK $@
cmd_ls3_llsc = $(CMD_LS3_LLSC) $@
CMD_RELOCS = arch/mips/boot/tools/relocs
quiet_cmd_relocs = RELOCS $@
cmd_relocs = $(CMD_RELOCS) $@
# `@true` prevents complaint when there is nothing to be done
vmlinux: FORCE
@true
ifeq ($(CONFIG_CPU_LOONGSON3_WORKAROUNDS),y)
$(call if_changed,ls3_llsc)
endif
ifeq ($(CONFIG_RELOCATABLE),y)
$(call if_changed,relocs)
endif
%.ko: FORCE
@true
clean:
@true
PHONY += FORCE clean
FORCE:
.PHONY: $(PHONY)