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Diffstat (limited to 'arch/mn10300/mm/Kconfig.cache')
| -rw-r--r-- | arch/mn10300/mm/Kconfig.cache | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/arch/mn10300/mm/Kconfig.cache b/arch/mn10300/mm/Kconfig.cache new file mode 100644 index 0000000..c4fd923 --- /dev/null +++ b/arch/mn10300/mm/Kconfig.cache @@ -0,0 +1,101 @@ +# +# 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" + help + The dcache operates in delayed write-back mode. It must be manually + flushed if writes are made that subsequently need to be executed or + to be DMA'd by a device. + +config MN10300_CACHE_WTHRU + bool "Write-Through" + help + The dcache operates in immediate write-through mode. Writes are + committed to RAM immediately in addition to being stored in the + cache. This means that the written data is immediately available for + execution or DMA. + + This is not available for use with an SMP kernel if cache flushing + and invalidation by automatic purge register is not selected. + +config MN10300_CACHE_DISABLED + bool "Disabled" + help + The icache and dcache are disabled. + +endchoice + +config MN10300_CACHE_ENABLED + def_bool y if !MN10300_CACHE_DISABLED + + +choice + prompt "CPU cache flush/invalidate method" + default MN10300_CACHE_MANAGE_BY_TAG if !AM34_2 + default MN10300_CACHE_MANAGE_BY_REG if AM34_2 + 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" + depends on !(SMP && MN10300_CACHE_WTHRU) + +config MN10300_CACHE_MANAGE_BY_REG + bool "Flush areas by way of automatic purge registers (AM34 only)" + depends on AM34_2 + +endchoice + +config MN10300_CACHE_INV_BY_TAG + def_bool y if MN10300_CACHE_MANAGE_BY_TAG && MN10300_CACHE_ENABLED + +config MN10300_CACHE_INV_BY_REG + def_bool y if MN10300_CACHE_MANAGE_BY_REG && MN10300_CACHE_ENABLED + +config MN10300_CACHE_FLUSH_BY_TAG + def_bool y if MN10300_CACHE_MANAGE_BY_TAG && MN10300_CACHE_WBACK + +config MN10300_CACHE_FLUSH_BY_REG + def_bool y if MN10300_CACHE_MANAGE_BY_REG && MN10300_CACHE_WBACK + + +config MN10300_HAS_CACHE_SNOOP + def_bool n + +config MN10300_CACHE_SNOOP + bool "Use CPU Cache Snooping" + depends on MN10300_CACHE_ENABLED && MN10300_HAS_CACHE_SNOOP + default y + +config MN10300_CACHE_FLUSH_ICACHE + def_bool y if MN10300_CACHE_WBACK && !MN10300_CACHE_SNOOP + help + Set if we need the dcache flushing before the icache is invalidated. + +config MN10300_CACHE_INV_ICACHE + def_bool y if MN10300_CACHE_WTHRU && !MN10300_CACHE_SNOOP + help + Set if we need the icache to be invalidated, even if the dcache is in + write-through mode and doesn't need flushing. |
