xtensa: add __bswap{si,di}2 helpers

gcc-13 may generate calls for __bswap{si,di}2. This breaks the kernel
build when optimization for size is selected. Add __bswap{si,di}2
helpers to fix that.

Cc: stable@vger.kernel.org
Fixes: 19c5699 ("xtensa: don't link with libgcc")
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

arch/xtensa/kernel/xtensa_ksyms.c

@@ -56,6 +56,8 @@ EXPORT_SYMBOL(empty_zero_page);
  */
 extern long long __ashrdi3(long long, int);
 extern long long __ashldi3(long long, int);
+extern long long __bswapdi2(long long);
+extern int __bswapsi2(int);
 extern long long __lshrdi3(long long, int);
 extern int __divsi3(int, int);
 extern int __modsi3(int, int);
@@ -66,6 +68,8 @@ extern unsigned long long __umulsidi3(unsigned int, unsigned int);
 
 EXPORT_SYMBOL(__ashldi3);
 EXPORT_SYMBOL(__ashrdi3);
+EXPORT_SYMBOL(__bswapdi2);
+EXPORT_SYMBOL(__bswapsi2);
 EXPORT_SYMBOL(__lshrdi3);
 EXPORT_SYMBOL(__divsi3);
 EXPORT_SYMBOL(__modsi3);

arch/xtensa/lib/Makefile

@@ -4,7 +4,7 @@
 #
 
 lib-y	+= memcopy.o memset.o checksum.o \
-	   ashldi3.o ashrdi3.o lshrdi3.o \
+	   ashldi3.o ashrdi3.o bswapdi2.o bswapsi2.o lshrdi3.o \
 	   divsi3.o udivsi3.o modsi3.o umodsi3.o mulsi3.o umulsidi3.o \
 	   usercopy.o strncpy_user.o strnlen_user.o
 lib-$(CONFIG_PCI) += pci-auto.o

arch/xtensa/lib/bswapdi2.S

@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0 */
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+ENTRY(__bswapdi2)
+
+	abi_entry_default
+	ssai	8
+	srli	a4, a2, 16
+	src	a4, a4, a2
+	src	a4, a4, a4
+	src	a4, a2, a4
+	srli	a2, a3, 16
+	src	a2, a2, a3
+	src	a2, a2, a2
+	src	a2, a3, a2
+	mov	a3, a4
+	abi_ret_default
+
+ENDPROC(__bswapdi2)

arch/xtensa/lib/bswapsi2.S

@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later WITH GCC-exception-2.0 */
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+ENTRY(__bswapsi2)
+
+	abi_entry_default
+	ssai	8
+	srli	a3, a2, 16
+	src	a3, a3, a2
+	src	a3, a3, a3
+	src	a2, a2, a3
+	abi_ret_default
+
+ENDPROC(__bswapsi2)