Hi Hans,
2016-04-09 20:53 GMT+09:00 Hans de Goede hdegoede@redhat.com:
v7_maint_dcache_all() does not work reliable when build with gcc6, see: https://bugzilla.redhat.com/show_bug.cgi?id=1318788
While debugging this I learned that v7_maint_dcache_all() is unreliable when build with gcc5 too when it is marked as noinline.
This commit fixes the reliability issues by replacing the C-code with the ready to use asm implementation from the kernel.
Given that this code when written as C-code clearly is quite fragile (also see the existing comments about the C-code being the way it is to get optimal assembly) and that we have a proven asm alternative, I believe that this is the best solution.
Note that we actually already had a copy of the kernel's v7_flush_dcache_all() before this commit in arch/arm/mach-uniphier/arm32/lowlevel_init.S.
This commit moves that code arch/arm/cpu/armv7/cache_v7_asm.S, renames it to __v7_flush_dcache_all(), and adds a v7_flush_dcache_all() wrapper which saves / restores the clobbered registers for use from C-code.
Signed-off-by: Hans de Goede hdegoede@redhat.com
Changes in v2: -Remove "Copyright (C) 2012-2015 Masahiro Yamada" from the header -Move the v7_flush_dcache_all asm code from arch/arm/mach-uniphier/arm32/lowlevel_init.S to arch/arm/cpu/armv7/cache_v7_asm.S instead of adding a second copy
arch/arm/cpu/armv7/Makefile | 2 +- arch/arm/cpu/armv7/cache_v7.c | 41 ++------------ arch/arm/cpu/armv7/cache_v7_asm.S | 84 ++++++++++++++++++++++++++++ arch/arm/mach-uniphier/arm32/lowlevel_init.S | 67 +--------------------- 4 files changed, 92 insertions(+), 102 deletions(-) create mode 100644 arch/arm/cpu/armv7/cache_v7_asm.S
I tested this patch on my board and I did not see any problem.
So, for mach-uniphier portion,
Acked-by: Masahiro Yamada yamada.masahiro@socionext.com
Thanks!