linux-dev/arch/mips/loongson2ef/Platform, branch master

MIPS: Loongson{2ef,64}: Wrap -mno-branch-likely with cc-option

2022-02-07T17:30:12Z

This flag is not supported by clang, which results in a warning: clang-14: warning: argument unused during compilation: '-mno-branch-likely' [-Wunused-command-line-argument] This breaks cc-option, which adds -Werror to make this warning fatal and catch flags that are not supported. Wrap this flag in cc-option so that it does not cause cc-option to fail, which can cause randconfigs to be really noisy, due to warnings not getting disabled that should be. Additionally, move the cc-option check to Kconfig so that the check is done at configuration time, rather than build time, as builds with no configuration change will be quicker because the cc-option call will not need to happen in those instances. Suggested-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Thomas Bogendoerfer

MIPS: Loongson2ef: Remove unnecessary {as,cc}-option calls

2021-12-09T09:27:14Z

When building with LLVM's integrated assembler, the build errors because it does not implement -mfix-loongson2f-{jump,nop}: arch/mips/loongson2ef/Platform:36: *** only binutils >= 2.20.2 have needed option -mfix-loongson2f-nop. Stop. The error is a little misleading because binutils are not being used in this case. To clear this up, remove the as-option calls because binutils 2.23 is the minimum supported version for building the kernel. At the same time, remove the cc-option calls for the '-march=' flags, as GCC 5.1.0 is the minimum supported version. This change will not fix the LLVM build for CONFIG_CPU_LOONGSON2{E,F}, as it does not implement the loongson2{e,f} march arguments (nor r4600, so it will error prior to this change) nor the assembler flags mentioned above but it will make the errors more obvious. Link: https://github.com/ClangBuiltLinux/linux/issues/1529 Reported-by: Ryutaroh Matsumoto Signed-off-by: Nathan Chancellor Signed-off-by: Thomas Bogendoerfer

MIPS: Loongson2ef: Disable Loongson MMI instructions

2020-09-23T12:47:22Z

It was missed when I was forking Loongson2ef from Loongson64 but should be applied to Loongson2ef as march=loongson2f will also enable Loongson MMI in GCC-9+. Signed-off-by: Jiaxun Yang Fixes: 71e2f4dd5a65 ("MIPS: Fork loongson2ef from loongson64") Reported-by: Thomas Bogendoerfer Cc: stable@vger.kernel.org # v5.8+ Signed-off-by: Thomas Bogendoerfer

MIPS: Loongson-2EF: disable fix-loongson3-llsc in compiler

2020-06-22T15:35:31Z

Firstly, Loongson-2EF support ll/sc instructions, but doesn't need fix-loongson3-llsc compile option. Secondly, fix-loongson3-llsc will cause kernel startup fail at futex_init, because compiler will add 'sync' before 'll', which will affect __ex_table. futex_init will pass NULL uaddr parameter to futex_atomic_cmpxchg_inatomic. futex_atomic_cmpxchg_inatomic will access uaddr directly, which will cause page fault exception, the exception should be handled by __ex_table's nextinsn if the exception insn exsit in __ex_table. Because __ex_table is affected by compiler, the exception can not be handled, and futex_atomic_cmpxchg_inatomic will crash. Error code as below: __ex_table.insn = 1b, which is 'sync' compiled with fix-loongson3-llsc, but the actual exception instrction is ll. So, do_page_fault will not find the correct inst in __ex_table, and can not handle this exception. "1: "user_ll("%1", "%3")" \n" " bne %1, %z4, 3f \n" " .set pop \n" " move $1, %z5 \n" " .set "MIPS_ISA_ARCH_LEVEL" \n" "2: "user_sc("$1", "%2")" \n" " beqz $1, 1b \n" "3: " __SYNC_ELSE(full, loongson3_war, __WEAK_LLSC_MB) "\n" " .insn \n" " .set pop \n" " .section .fixup,\"ax\" \n" "4: li %0, %6 \n" " j 3b \n" " .previous \n" " .section __ex_table,\"a\" \n" " "__UA_ADDR "\t1b, 4b \n" " "__UA_ADDR "\t2b, 4b \n" " .previous Signed-off-by: Lichao Liu Reviewed-by: Jiaxun Yang Signed-off-by: Thomas Bogendoerfer

MIPS: Only include the platform file needed

2020-05-12T22:17:18Z

Instead of including all Platform files, we simply include the needed one and avoid clashes with makefile variables. Signed-off-by: Thomas Bogendoerfer

MIPS: Fork loongson2ef from loongson64

2019-11-01T21:30:52Z

As later model of GSx64 family processors including 2-series-soc have similar design with initial loongson3a while loongson2e/f seems less identical, we separate loongson2e/f support code out of mach-loongson64 to make our life easier. This patch contains mostly file moving works. Signed-off-by: Jiaxun Yang [paulburton@kernel.org: Squash in the MAINTAINERS updates] Signed-off-by: Paul Burton Cc: linux-mips@vger.kernel.org Cc: paul.burton@mips.com