CONFIG_BFIN_EXTMEM_WRITETHROUGH is not available for thedefaultarchitecture x86.
Result is shown for architecture blackfin
default or selected kernelversion does not have config value CONFIG_BFIN_EXTMEM_WRITETHROUGH.
Result is shown for kernelversion 6.7-rc3
Write through
configname: CONFIG_BFIN_EXTMEM_WRITETHROUGH
External memory DCACHE policy
└─>Write through
In linux kernel since version 2.6.31 (release Date: 2009-09-09)
Write Back Policy:
Cached data will be written back to SDRAM only when needed.
This can give a nice increase in performance, but beware of
broken drivers that do not properly invalidate/flush their
cache.
Write Through Policy:
Cached data will always be written back to SDRAM when the
cache is updated. This is a completely safe setting, but
performance is worse than Write Back.
If you are unsure of the options and you want to be safe,
then go with Write Through.
Cached data will be written back to SDRAM only when needed.
This can give a nice increase in performance, but beware of
broken drivers that do not properly invalidate/flush their
cache.
Write Through Policy:
Cached data will always be written back to SDRAM when the
cache is updated. This is a completely safe setting, but
performance is worse than Write Back.
If you are unsure of the options and you want to be safe,
then go with Write Through.