README: Update reference to AMBA 5 spec for atomic transactions

README.md

@@ -75,15 +75,15 @@ In addition to the modules above, which are available in synthesis and simulatio
 
 ## Atomic Operations
 
-AXI4+ATOPs means the full AXI4 specification plus atomic operations (ATOPs) as defined in Section E2.1 of the AMBA5 specification. This has the following implications for modules that do not implement ATOPs and systems that include such modules:
+AXI4+ATOPs means the full AXI4 specification plus atomic operations (ATOPs) as defined in Section E1.1 of the AMBA5 specification. This has the following implications for modules that do not implement ATOPs and systems that include such modules:
 
 - Masters that do not issue ATOPs must set `aw_atop` to `'0`.
 - Slaves that do not support ATOPs must specify this in their interface documentation and can ignore the `aw_atop` signal.
 - System designers are responsible for ensuring that
   1. slaves that do not support ATOPs are behind an [`axi_atop_filter`](src/axi_atop_filter.sv) if any master could issue an ATOP to such slaves and
   2. the `aw_atop` signal is well-defined at the input of any (non-AXI4-Lite) module in this repository.
 
-Masters and slaves that do support ATOPs must adhere to Section E2.1 of the AMBA5 specification.
+Masters and slaves that do support ATOPs must adhere to Section E1.1 of the AMBA5 specification.
 
 
 ## Which EDA Tools Are Supported?