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-rw-r--r--meta/conf/machine/include/tune-thumb.inc32
1 files changed, 32 insertions, 0 deletions
diff --git a/meta/conf/machine/include/tune-thumb.inc b/meta/conf/machine/include/tune-thumb.inc
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1#tune file for thumb instructions
2
3ARM_INSTRUCTION_SET ?= "arm"
4# "arm" "thumb"
5# The instruction set the compiler should use when generating application
6# code. The kernel is always compiled with arm code at present. arm code
7# is the original 32 bit ARM instruction set, thumb code is the 16 bit
8# encoded RISC sub-set. Thumb code is smaller (maybe 70% of the ARM size)
9# but requires more instructions (140% for 70% smaller code) so may be
10# slower.
11
12THUMB_INTERWORK ?= "yes"
13# "yes" "no"
14# Whether to compile with code to allow interworking between the two
15# instruction sets. This allows thumb code to be executed on a primarily
16# arm system and vice versa. It is strongly recommended that DISTROs not
17# turn this off - the actual cost is very small.
18
19OVERRIDE_THUMB = "${@['', ':thumb'][bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == 'thumb']}"
20OVERRIDE_INTERWORK = "${@['', ':thumb-interwork'][bb.data.getVar('THUMB_INTERWORK', d, 1) == 'yes']}"
21OVERRIDES .= "${OVERRIDE_THUMB}${OVERRIDE_INTERWORK}"
22
23# Compiler and linker options for application code and kernel code. These
24# options ensure that the compiler has the correct settings for the selected
25# instruction set and interworking.
26ARM_INTERWORK_M_OPT = "${@['-mno-thumb-interwork', '-mthumb-interwork'][bb.data.getVar('THUMB_INTERWORK', d, 1) == 'yes']}"
27ARM_THUMB_M_OPT = "${@['-mno-thumb', '-mthumb'][bb.data.getVar('ARM_INSTRUCTION_SET', d, 1) == 'thumb']}"
28
29#
30TARGET_CC_ARCH += "${ARM_INTERWORK_M_OPT} ${ARM_THUMB_M_OPT}"
31TARGET_CC_KERNEL_ARCH += "-mno-thumb-interwork -mno-thumb"
32