OpenSDV
/
linux-stable-rt
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
linux-stable-rt/arch/mn10300/mm/Kconfig.cache

67 lines
1.8 KiB
Plaintext
Raw Normal View History

MN10300: Cache: Split cache bits out of arch Kconfig Split the cache bits out of arch/mn10300/Kconfig as they're quite complex. Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:41 +08:00
#
# MN10300 CPU cache options
#
choice
prompt "CPU Caching mode"
default MN10300_CACHE_WBACK
help
This option determines the caching mode for the kernel.
Write-Back caching mode involves the all reads and writes causing
the affected cacheline to be read into the cache first before being
operated upon. Memory is not then updated by a write until the cache
is filled and a cacheline needs to be displaced from the cache to
make room. Only at that point is it written back.
Write-Through caching only fetches cachelines from memory on a
read. Writes always get written directly to memory. If the affected
cacheline is also in cache, it will be updated too.
The final option is to turn of caching entirely.
config MN10300_CACHE_WBACK
bool "Write-Back"
config MN10300_CACHE_WTHRU
bool "Write-Through"
config MN10300_CACHE_DISABLED
bool "Disabled"
endchoice
MN10300: Provide a MN10300_CACHE_ENABLED config option Provide a MN10300_CACHE_ENABLED config option as inverted logic of MN10300_CACHE_DISABLED to make things simpler. Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:42 +08:00
config MN10300_CACHE_ENABLED
def_bool y if !MN10300_CACHE_DISABLED
MN10300: AM34: The current cacheflush routines operate by controlling tag regs The current cache flush and invalidate routines operate by controlling the cache tag registers. Rename the files and add config items to select them. This makes it easier to support the use of other cache flush methods instead, such as the use of AM34's area purge registers, if available. Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:43 +08:00
choice
prompt "CPU cache flush/invalidate method"
MN10300: AM34: Add cacheflushing by using the AM34 purge registers The AM34 CPU core provides an automated way of purging the cache rather than manually iterating over all the tags in the cache. Make it possible to use these. Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com> Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:45 +08:00
default MN10300_CACHE_MANAGE_BY_TAG if !AM34_2
default MN10300_CACHE_MANAGE_BY_REG if AM34_2
MN10300: AM34: The current cacheflush routines operate by controlling tag regs The current cache flush and invalidate routines operate by controlling the cache tag registers. Rename the files and add config items to select them. This makes it easier to support the use of other cache flush methods instead, such as the use of AM34's area purge registers, if available. Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:43 +08:00
depends on MN10300_CACHE_ENABLED
help
This determines the method by which CPU cache flushing and
invalidation is performed.
config MN10300_CACHE_MANAGE_BY_TAG
bool "Use the cache tag registers directly"
MN10300: AM34: Add cacheflushing by using the AM34 purge registers The AM34 CPU core provides an automated way of purging the cache rather than manually iterating over all the tags in the cache. Make it possible to use these. Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com> Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:45 +08:00
config MN10300_CACHE_MANAGE_BY_REG
bool "Flush areas by way of automatic purge registers (AM34 only)"
depends on AM34_2
MN10300: AM34: The current cacheflush routines operate by controlling tag regs The current cache flush and invalidate routines operate by controlling the cache tag registers. Rename the files and add config items to select them. This makes it easier to support the use of other cache flush methods instead, such as the use of AM34's area purge registers, if available. Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:43 +08:00
endchoice
config MN10300_CACHE_INV_BY_TAG
def_bool y if MN10300_CACHE_MANAGE_BY_TAG && MN10300_CACHE_ENABLED
MN10300: AM34: Add cacheflushing by using the AM34 purge registers The AM34 CPU core provides an automated way of purging the cache rather than manually iterating over all the tags in the cache. Make it possible to use these. Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com> Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:45 +08:00
config MN10300_CACHE_INV_BY_REG
def_bool y if MN10300_CACHE_MANAGE_BY_REG && MN10300_CACHE_ENABLED
MN10300: AM34: The current cacheflush routines operate by controlling tag regs The current cache flush and invalidate routines operate by controlling the cache tag registers. Rename the files and add config items to select them. This makes it easier to support the use of other cache flush methods instead, such as the use of AM34's area purge registers, if available. Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:43 +08:00
config MN10300_CACHE_FLUSH_BY_TAG
def_bool y if MN10300_CACHE_MANAGE_BY_TAG && MN10300_CACHE_WBACK
MN10300: AM34: Add cacheflushing by using the AM34 purge registers The AM34 CPU core provides an automated way of purging the cache rather than manually iterating over all the tags in the cache. Make it possible to use these. Signed-off-by: Akira Takeuchi <takeuchi.akr@jp.panasonic.com> Signed-off-by: Kiyoshi Owada <owada.kiyoshi@jp.panasonic.com> Signed-off-by: David Howells <dhowells@redhat.com>
2010-10-28 00:28:45 +08:00
config MN10300_CACHE_FLUSH_BY_REG
def_bool y if MN10300_CACHE_MANAGE_BY_REG && MN10300_CACHE_WBACK