Commit Graph

6 Commits

Author SHA1 Message Date
Nathan Chancellor
d49fc69293 MIPS: Loongson{2ef,64}: Wrap -mno-branch-likely with cc-option
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 <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2022-02-07 18:30:12 +01:00
Nathan Chancellor
13ceb48bc1 MIPS: Loongson2ef: Remove unnecessary {as,cc}-option calls
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 <ryutaroh@ict.e.titech.ac.jp>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2021-12-09 10:27:14 +01:00
Jiaxun Yang
b13812ddea MIPS: Loongson2ef: Disable Loongson MMI instructions
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 <jiaxun.yang@flygoat.com>
Fixes: 71e2f4dd5a ("MIPS: Fork loongson2ef from loongson64")
Reported-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-09-23 14:47:22 +02:00
Lichao Liu
2984b3f8c2 MIPS: Loongson-2EF: disable fix-loongson3-llsc in compiler
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 <liulichao@loongson.cn>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-06-22 17:35:31 +02:00
Thomas Bogendoerfer
26bff9eb49 MIPS: Only include the platform file needed
Instead of including all Platform files, we simply include the
needed one and avoid clashes with makefile variables.

Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
2020-05-13 00:17:18 +02:00
Jiaxun Yang
71e2f4dd5a
MIPS: Fork loongson2ef from loongson64
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 <jiaxun.yang@flygoat.com>
[paulburton@kernel.org: Squash in the MAINTAINERS updates]
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: paul.burton@mips.com
2019-11-01 14:30:52 -07:00