Index: sys/conf/kern.pre.mk
===================================================================
--- sys/conf/kern.pre.mk
+++ sys/conf/kern.pre.mk
@@ -184,8 +184,9 @@
 	  ${CC} -c ${CFLAGS} ${WERROR} ${PROF} ${.PREFIX}.c
 
 NORMAL_FW= uudecode -o ${.TARGET} ${.ALLSRC}
-NORMAL_FWO= ${LD} -b binary --no-warn-mismatch -d -warn-common -r \
-	-m ${LD_EMULATION} -o ${.TARGET} ${.ALLSRC:M*.fw}
+NORMAL_FWO= ${CC:N${CCACHE_BIN}} -c ${ASM_CFLAGS} ${WERROR} -o ${.TARGET} \
+	$S/kern/firmw.S -DFIRMW_FILE="${.ALLSRC:M*.fw}" \
+	-DFIRMW_SYMBOL="${.ALLSRC:M*.fw:C/[-.\/]/_/g}"
 
 # for ZSTD in the kernel (include zstd/lib/freebsd before other CFLAGS)
 ZSTD_C= ${CC} -c -DZSTD_HEAPMODE=1 -I$S/contrib/zstd/lib/freebsd ${CFLAGS} -I$S/contrib/zstd/lib -I$S/contrib/zstd/lib/common ${WERROR} -Wno-inline -Wno-missing-prototypes ${PROF} -U__BMI__ ${.IMPSRC}
Index: sys/conf/kmod.mk
===================================================================
--- sys/conf/kmod.mk
+++ sys/conf/kmod.mk
@@ -187,19 +187,13 @@
 CLEANFILES+=	${KMOD:S/$/.c/}
 
 .for _firmw in ${FIRMWS}
-${_firmw:C/\:.*$/.fwo/:T}:	${_firmw:C/\:.*$//}
+${_firmw:C/\:.*$/.fwo/:T}:	${_firmw:C/\:.*$//} ${SYSDIR}/kern/firmw.S
 	@${ECHO} ${_firmw:C/\:.*$//} ${.ALLSRC:M*${_firmw:C/\:.*$//}}
-	@if [ -e ${_firmw:C/\:.*$//} ]; then			\
-		${LD} -b binary --no-warn-mismatch ${_LDFLAGS}	\
-		    -m ${LD_EMULATION} -r -d			\
-		    -o ${.TARGET} ${_firmw:C/\:.*$//};		\
-	else							\
-		ln -s ${.ALLSRC:M*${_firmw:C/\:.*$//}} ${_firmw:C/\:.*$//}; \
-		${LD} -b binary --no-warn-mismatch ${_LDFLAGS}	\
-		    -m ${LD_EMULATION} -r -d			\
-		    -o ${.TARGET} ${_firmw:C/\:.*$//};		\
-		rm ${_firmw:C/\:.*$//};				\
-	fi
+	${CC:N${CCACHE_BIN}} -c -x assembler-with-cpp -DLOCORE 	\
+	    ${CFLAGS} ${WERROR} 				\
+	    -DFIRMW_FILE="${.ALLSRC:M*${_firmw:C/\:.*$//}}" 	\
+	    -DFIRMW_SYMBOL="${_firmw:C/\:.*$//:C/[-.\/]/_/g}"	\
+	    ${SYSDIR}/kern/firmw.S -o ${.TARGET}
 
 OBJS+=	${_firmw:C/\:.*$/.fwo/:T}
 .endfor
Index: sys/kern/firmw.S
===================================================================
--- /dev/null
+++ sys/kern/firmw.S
@@ -0,0 +1,47 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2020 John Baldwin <jhb@FreeBSD.org>
+ *
+ * This software was developed by SRI International and the University of
+ * Cambridge Computer Laboratory (Department of Computer Science and
+ * Technology) under DARPA contract HR0011-18-C-0016 ("ECATS"), as part of the
+ * DARPA SSITH research programme.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+
+#define	FIRMW_START(S)	__CONCAT(_binary_, __CONCAT(S, _start))
+#define	FIRMW_END(S)	__CONCAT(_binary_, __CONCAT(S, _end))
+
+	.section rodata, "a", %progbits
+	.globl	FIRMW_START(FIRMW_SYMBOL)
+	.type	FIRMW_START(FIRMW_SYMBOL), %object
+FIRMW_START(FIRMW_SYMBOL):
+	.incbin	__XSTRING(FIRMW_FILE)
+	.size	FIRMW_START(FIRMW_SYMBOL), . - FIRMW_START(FIRMW_SYMBOL)
+	.globl	FIRMW_END(FIRMW_SYMBOL)
+	.type	FIRMW_END(FIRMW_SYMBOL), %object
+FIRMW_END(FIRMW_SYMBOL):
+	.size	FIRMW_END(FIRMW_SYMBOL), . - FIRMW_END(FIRMW_SYMBOL)
Index: sys/tools/fw_stub.awk
===================================================================
--- sys/tools/fw_stub.awk
+++ sys/tools/fw_stub.awk
@@ -143,7 +143,7 @@
 
 for (file_i = 0; file_i < num_files; file_i++) {
 	symb = filenames[file_i];
-	# '-', '.' and '/' are converted to '_' by ld/objcopy
+	# '-', '.' and '/' are converted to '_'
 	gsub(/-|\.|\//, "_", symb);
 	printc("extern char _binary_" symb "_start[], _binary_" symb "_end[];");
 }
@@ -170,7 +170,7 @@
 	short = shortnames[file_i];
 	symb = filenames[file_i];
 	version = versions[file_i];
-	# '-', '.' and '/' are converted to '_' by ld/objcopy
+	# '-', '.' and '/' are converted to '_'
 	gsub(/-|\.|\//, "_", symb);
 
 	reg = "\t\tfp = ";