diff --git a/lang/mono/Makefile b/lang/mono/Makefile
index e8094d46e013..541b96c9dd10 100644
--- a/lang/mono/Makefile
+++ b/lang/mono/Makefile
@@ -1,94 +1,102 @@
 # Created by: Yukihiro Nakai <nakai@FreeBSD.org>
 
 PORTNAME=	mono
 PORTVERSION=	5.10.1.57
 PORTREVISION=	3
 CATEGORIES=	lang
 MASTER_SITES=	https://download.mono-project.com/sources/mono/
 DISTFILES=	${PORTNAME}-${PORTVERSION}${EXTRACT_SUFX}
 
 MAINTAINER=	mono@FreeBSD.org
 COMMENT=	Open source implementation of .NET Development Framework
 
 LICENSE=	MIT
 LICENSE_FILE=	${WRKSRC}/LICENSE
 
 ONLY_FOR_ARCHS=		amd64 armv6 armv7 i386 powerpc
 
 BUILD_DEPENDS=	p5-XML-Parser>=0:textproc/p5-XML-Parser \
 		bash:shells/bash \
 		cmake>0:devel/cmake
 LIB_DEPENDS=	libinotify.so:devel/libinotify
 RUN_DEPENDS=	${PY_PILLOW} \
 		ca_root_nss>=0:security/ca_root_nss
 
 CONFLICTS_INSTALL=	czmq-3*
 
 OPTIONS_DEFINE=		MONOLITE NLS X11
 OPTIONS_DEFAULT=	MONOLITE X11
 OPTIONS_SUB=	yes
 
 MONOLITE_DESC=		Use monolite to bootstrap mcs (otherwise use installed mcs)
 MONOLITE_DISTFILES=	monolite-linux-${MONOLITE_VERSION}-latest.tar.gz:monolite
 MONOLITE_MASTER_SITES=	http://download.mono-project.com/monolite/:monolite
 MONOLITE_VERSION=	1051000004
 
 NLS_CONFIGURE_OFF=	--disable-nls
 NLS_USES=	gettext
 
 X11_USES=	display:test
 
 USES=	autoreconf bison compiler:c11 cpe gmake iconv libtool \
 	pathfix perl5 python:3.6+ shebangfix tar:bzip2
 USE_PERL5=	build
 GNU_CONFIGURE=	yes
 USE_LDCONFIG=	yes
 SHEBANG_FILES=	scripts/mono-heapviz mono/mini/genmdesc.py mono/tests/test_lldb.py
 BINARY_ALIAS=	python=${PYTHON_CMD}
 
-CONFIGURE_ARGS=	--disable-dtrace --enable-btls
+CONFIGURE_ARGS=	--disable-dtrace
 CONFIGURE_ENV=	ac_cv_header_sys_inotify_h=no
 
 MAKE_ENV=	MONO_SHARED_DIR="${WRKDIR}" \
 		INSTALL_STRIP_FLAG="${STRIP}" \
 		TZ=UTC
 
 TEST_ARGS=	-k
 TEST_TARGET=	check
 
 PORTSCOUT=	limit:^\d+\.\d+\.[1-9]\d*
 
 LOCALBASE?=	/usr/local
 .if !exists(${LOCALBASE}/bin/mcs)
 OPTIONS_SLAVE=	MONOLITE
 .endif
 
+.include <bsd.port.options.mk>
+
+.if ${ARCH} == powerpc
+PLIST+=	${.CURDIR}/pkg-plist.powerpc
+.else
+CONFIGURE_ARGS+=	--enable-btls
+.endif
+
 post-extract-MONOLITE-on:
 	${MKDIR} ${WRKSRC}/mcs/class/lib/monolite-linux
 	${MV} ${WRKDIR}/monolite-linux-${MONOLITE_VERSION}-latest ${WRKSRC}/mcs/class/lib/monolite-linux/${MONOLITE_VERSION}
 
 post-patch:
 	${REINPLACE_CMD} -e 's|^#!/bin/bash|#!/usr/bin/env bash|g' \
 		${WRKSRC}/scripts/mono-find-provides.in \
 		${WRKSRC}/scripts/mono-find-requires.in \
 		${WRKSRC}/scripts/mono-test-install
 	${FIND} ${WRKSRC} -name '*.sh' | ${XARGS} ${REINPLACE_CMD} \
 		-e 's|^#!/bin/bash|#!/bin/sh|g'
 	${SED} 's/tarball/${PORTVERSION}/' ${WRKSRC}/mono/mini/Makefile.am.in \
 		> ${WRKSRC}/mono/mini/Makefile.am
 	${REINPLACE_CMD} -e 's|/usr/share|${PREFIX}|g' \
 		${WRKSRC}/mcs/class/corlib/System/Environment.cs \
 		${WRKSRC}/external/corefx/src/System.Runtime.Extensions/src/System/Environment.Unix.cs
 	${REINPLACE_CMD} -e 's|/usr/share/.mono|${PREFIX}/share/mono|g' \
 		${WRKSRC}/man/mono-configuration-crypto.1 \
 		${WRKSRC}/man/mono.1 \
 		${WRKSRC}/man/mozroots.1
 
 post-configure:
 	${REINPLACE_CMD} -e 's|share\/man|man|g' \
 		${WRKSRC}/mcs/jay/Makefile
 
 post-install:
 	${MKDIR} ${STAGEDIR}${PREFIX}/mono
 
 .include <bsd.port.mk>
diff --git a/lang/mono/files/patch-mono_utils_mono-sigcontext.h b/lang/mono/files/patch-mono_utils_mono-sigcontext.h
new file mode 100644
index 000000000000..22cf2458435d
--- /dev/null
+++ b/lang/mono/files/patch-mono_utils_mono-sigcontext.h
@@ -0,0 +1,17 @@
+--- mono/utils/mono-sigcontext.h.orig	2021-10-05 20:43:22.170433000 +0200
++++ mono/utils/mono-sigcontext.h	2021-10-05 20:43:36.848022000 +0200
+@@ -363,10 +363,10 @@
+ #elif defined(__FreeBSD__)
+ 	typedef ucontext_t os_ucontext;
+ 
+-	#define UCONTEXT_REG_Rn(ctx, n)   ((ctx)->uc_mcontext.mc_gpr [(n)])
+-	#define UCONTEXT_REG_FPRn(ctx, n) ((ctx)->uc_mcontext.mc_fpreg [(n)])
+-	#define UCONTEXT_REG_NIP(ctx)     ((ctx)->uc_mcontext.mc_srr0)
+-	#define UCONTEXT_REG_LNK(ctx)     ((ctx)->uc_mcontext.mc_lr)
++	#define UCONTEXT_REG_Rn(ctx, n)   (((os_ucontext*)(ctx))->uc_mcontext.mc_gpr [(n)])
++	#define UCONTEXT_REG_FPRn(ctx, n) (((os_ucontext*)(ctx))->uc_mcontext.mc_fpreg [(n)])
++	#define UCONTEXT_REG_NIP(ctx)     (((os_ucontext*)(ctx))->uc_mcontext.mc_srr0)
++	#define UCONTEXT_REG_LNK(ctx)     (((os_ucontext*)(ctx))->uc_mcontext.mc_lr)
+ #endif
+ 
+ #elif defined(TARGET_ARM)