diff options
| author | Paul Burton | 2018-11-08 23:44:55 +0000 |
|---|---|---|
| committer | Paul Burton | 2018-11-12 14:26:16 -0800 |
| commit | 57eeacede4db235891ddc37544262413f909763e (patch) | |
| tree | cf373c0297e703460de5348b34a50efa9e53ed2a /arch/mips/Kconfig | |
| parent | 47bf2b031754ce6f02345a0353f21def75ccd5fc (diff) | |
MIPS: Use Kconfig to select CPU_NO_EFFICIENT_FFS
Select CONFIG_CPU_NO_EFFICIENT_FFS via Kconfig when the kernel is
configured for a pre-MIPS32r1 CPU, rather than defining its equivalent
in asm/cpu-features.h based upon overrides of cpu_has_mips* macros.
The latter only works if a platform has an cpu-feature-overrides.h
header which defines cpu_has_mips* macros, which are not generally
needed. There are many cases where we know that the target ISA for a
kernel build is MIPS32r1 or later & thus includes the CLZ instruction,
without requiring any overrides from the platform. Using Kconfig allows
us to take those into account, and more naturally make a decision about
instruction support using information about the target ISA.
Signed-off-by: Paul Burton <paul.burton@mips.com>
Patchwork: https://patchwork.linux-mips.org/patch/21045/
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Zhaoxiu Zeng <zhaoxiu.zeng@gmail.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Diffstat (limited to 'arch/mips/Kconfig')
| -rw-r--r-- | arch/mips/Kconfig | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 513a9c8b6058..6eb17b4a617f 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -15,6 +15,7 @@ config MIPS select ARCH_WANT_IPC_PARSE_VERSION select BUILDTIME_EXTABLE_SORT select CLONE_BACKWARDS + select CPU_NO_EFFICIENT_FFS if (TARGET_ISA_REV < 1) select CPU_PM if CPU_IDLE select DMA_DIRECT_OPS select GENERIC_ATOMIC64 if !64BIT @@ -2031,7 +2032,7 @@ config CPU_MIPS64 default y if CPU_MIPS64_R1 || CPU_MIPS64_R2 || CPU_MIPS64_R6 # -# These two indicate the revision of the architecture, either Release 1 or Release 2 +# These indicate the revision of the architecture # config CPU_MIPSR1 bool @@ -2052,6 +2053,16 @@ config CPU_MIPSR6 select MIPS_CRC_SUPPORT select MIPS_SPRAM +config TARGET_ISA_REV + int + default 1 if CPU_MIPSR1 + default 2 if CPU_MIPSR2 + default 6 if CPU_MIPSR6 + default 0 + help + Reflects the ISA revision being targeted by the kernel build. This + is effectively the Kconfig equivalent of MIPS_ISA_REV. + config EVA bool |