diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b896b420..5bddc9553 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -118,8 +118,6 @@ elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "(ppc|powerpc)")
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "s390x")
     set(ARCH "s390x")
     set(ARCH_S390X ON)
-    # CROSS not supported on big-endian (https://github.com/open-quantum-safe/liboqs/issues/1961)
-    set(OQS_ENABLE_SIG_CROSS OFF)
     if(${OQS_DIST_BUILD})
         set(OQS_DIST_S390X_BUILD ON)
     endif()
diff --git a/PLATFORMS.md b/PLATFORMS.md
index d33efa272..7bd573338 100644
--- a/PLATFORMS.md
+++ b/PLATFORMS.md
@@ -60,3 +60,5 @@ In this policy, the words "must" and "must not" specify absolute requirements th
 ### Tier 3
 
 - x86 for Windows (Visual Studio Toolchain)
+- ppc641e for Ubuntu (Focal)
+- s390x for Ubuntu (Focal)
diff --git a/README.md b/README.md
index e2b55b91c..b9a0d9f5d 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,7 @@ liboqs
 
 [![Main Branch Tests](https://github.com/open-quantum-safe/liboqs/actions/workflows/commit-to-main.yml/badge.svg)](https://github.com/open-quantum-safe/liboqs/actions/workflows/commit-to-main.yml)
 [![Weekly Tests](https://github.com/open-quantum-safe/liboqs/actions/workflows/weekly.yml/badge.svg)](https://github.com/open-quantum-safe/liboqs/actions/workflows/weekly.yml)
+![Travis Build Status](https://img.shields.io/travis/com/open-quantum-safe/liboqs?logo=travis&label=Travis%20CI&labelColor=%23343B42&color=%232EBB4E)
 
 liboqs is an open source C library for quantum-safe cryptographic algorithms.