diff options
Diffstat (limited to 'mk/config.mk')
| -rw-r--r-- | mk/config.mk | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/mk/config.mk b/mk/config.mk index 148a4b42..c00a1461 100644 --- a/mk/config.mk +++ b/mk/config.mk @@ -154,6 +154,26 @@ CFG_RPMB_FS_DEV_ID ?= 0 # config files CFG_RPMB_FS_RD_ENTRIES ?= 8 +# Enables caching of FAT FS entries when set to a value greater than zero. +# When enabled, the cache stores the first 'CFG_RPMB_FS_CACHE_ENTRIES' FAT FS +# entries. The cache is populated when FAT FS entries are initially read in. +# When traversing the FAT FS entries, we read from the cache instead of reading +# in the entries from RPMB storage. Consequently, when a FAT FS entry is +# written, the cache is updated. In scenarios where an estimate of the number +# of FAT FS entries can be made, the cache may be specifically tailored to +# store all entries. The caching can improve RPMB I/O at the cost +# of additional memory. +# Without caching, we temporarily require +# CFG_RPMB_FS_RD_ENTRIES*sizeof(struct rpmb_fat_entry) bytes of heap memory +# while traversing the FAT FS (e.g. in read_fat). +# For example 8*256 bytes = 2kB while in read_fat. +# With caching, we constantly require up to +# CFG_RPMB_FS_CACHE_ENTRIES*sizeof(struct rpmb_fat_entry) bytes of heap memory +# depending on how many elements are in the cache, and additional temporary +# CFG_RPMB_FS_RD_ENTRIES*sizeof(struct rpmb_fat_entry) bytes of heap memory +# in case the cache is too small to hold all elements when traversing. +CFG_RPMB_FS_CACHE_ENTRIES ?= 0 + # Enables RPMB key programming by the TEE, in case the RPMB partition has not # been configured yet. # !!! Security warning !!! |