diff options
Diffstat (limited to 'conf')
| -rw-r--r-- | conf/machine/include/tune-thumb.conf | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/conf/machine/include/tune-thumb.conf b/conf/machine/include/tune-thumb.conf index 862c2c3fcc..02c4fd0927 100644 --- a/conf/machine/include/tune-thumb.conf +++ b/conf/machine/include/tune-thumb.conf @@ -1,2 +1,32 @@ -TARGET_CC_ARCH += " -mthumb " +#tune file for thumb instructions + +ARM_INSTRUCTION_SET ?= "thumb" +# "arm" "thumb" +# The instruction set the compiler should use when generating application +# code. The kernel is always compiled with arm code at present. arm code +# is the original 32 bit ARM instruction set, thumb code is the 16 bit +# encoded RISC sub-set. Thumb code is smaller (maybe 70% of the ARM size) +# but requires more instructions (140% for 70% smaller code) so may be +# slower. + +THUMB_INTERWORK ?= "yes" +# "yes" "no" +# Whether to compile with code to allow interworking between the two +# instruction sets. This allows thumb code to be executed on a primarily +# arm system and vice versa. It is strongly recommended that DISTROs not +# turn this off - the actual cost is very small. + +OVERRIDE_THUMB = "${@['', ':thumb'][bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == 'thumb']}" +OVERRIDE_INTERWORK = "${@['', ':thumb-interwork'][bb.data.getVar('THUMB_INTERWORK', d, 1) == 'yes']}" +OVERRIDES += "${OVERRIDE_THUMB}${OVERRIDE_INTERWORK}" + +# Compiler and linker options for application code and kernel code. These +# options ensure that the compiler has the correct settings for the selected +# instruction set and interworking. +ARM_INTERWORK_M_OPT = "${@['-mno-thumb-interwork', '-mthumb-interwork'][bb.data.getVar('THUMB_INTERWORK', d, 1) == 'yes']}" +ARM_THUMB_M_OPT = "${@['-mno-thumb', '-mthumb'][bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == 'thumb']}" + +# +TARGET_CC_ARCH = + "${ARM_INTERWORK_M_OPT} ${ARM_THUMB_M_OPT}" +TARGET_CC_KERNEL_ARCH =+ "-mno-thumb" |