diff --git a/docs/porting-guide.md b/docs/porting-guide.md index aa014f159..7534e395f 100644 --- a/docs/porting-guide.md +++ b/docs/porting-guide.md @@ -1087,13 +1087,15 @@ The default implementation spins forever. Argument : uintptr_t mem_base, unsigned int mem_size, unsigned int flags - Return : void + Return : int BL1 calls this function while handling FWU copy and authenticate SMCs. The platform must ensure that the provided `mem_base` and `mem_size` are mapped into BL1, and that this memory corresponds to either a secure or non-secure memory region as indicated by the security state of the `flags` argument. +This function must return 0 on success, a non-null error code otherwise. + The default implementation of this function asserts therefore platforms must override it when using the FWU feature.