Resguardo inicial

linux-7.2.3/arch/xtensa/lib/Makefile

@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for Xtensa-specific library files.
+#
+
+lib-y	+= memcopy.o memset.o checksum.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 strnlen_user.o
+lib-$(CONFIG_ARCH_HAS_STRNCPY_FROM_USER) += strncpy_user.o
+lib-$(CONFIG_PCI) += pci-auto.o

linux-7.2.3/arch/xtensa/lib/ashldi3.S

@@ -0,0 +1,29 @@
+/* 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>
+
+#ifdef __XTENSA_EB__
+#define uh a2
+#define ul a3
+#else
+#define uh a3
+#define ul a2
+#endif /* __XTENSA_EB__ */
+
+ENTRY(__ashldi3)
+
+	abi_entry_default
+	ssl	a4
+	bgei	a4, 32, .Llow_only
+	src	uh, uh, ul
+	sll	ul, ul
+	abi_ret_default
+
+.Llow_only:
+	sll	uh, ul
+	movi	ul, 0
+	abi_ret_default
+
+ENDPROC(__ashldi3)
+EXPORT_SYMBOL(__ashldi3)

linux-7.2.3/arch/xtensa/lib/ashrdi3.S

@@ -0,0 +1,29 @@
+/* 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>
+
+#ifdef __XTENSA_EB__
+#define uh a2
+#define ul a3
+#else
+#define uh a3
+#define ul a2
+#endif /* __XTENSA_EB__ */
+
+ENTRY(__ashrdi3)
+
+	abi_entry_default
+	ssr	a4
+	bgei	a4, 32, .Lhigh_only
+	src	ul, uh, ul
+	sra	uh, uh
+	abi_ret_default
+
+.Lhigh_only:
+	sra	ul, uh
+	srai	uh, uh, 31
+	abi_ret_default
+
+ENDPROC(__ashrdi3)
+EXPORT_SYMBOL(__ashrdi3)

linux-7.2.3/arch/xtensa/lib/bswapdi2.S

@@ -0,0 +1,22 @@
+/* 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)
+EXPORT_SYMBOL(__bswapdi2)

linux-7.2.3/arch/xtensa/lib/bswapsi2.S

@@ -0,0 +1,17 @@
+/* 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)
+EXPORT_SYMBOL(__bswapsi2)

linux-7.2.3/arch/xtensa/lib/checksum.S

@@ -0,0 +1,359 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * INET		An implementation of the TCP/IP protocol suite for the LINUX
+ *		operating system.  INET is implemented using the  BSD Socket
+ *		interface as the means of communication with the user level.
+ *
+ *		IP/TCP/UDP checksumming routines
+ *
+ * Xtensa version:  Copyright (C) 2001 Tensilica, Inc. by Kevin Chea
+ *                  Optimized by Joe Taylor
+ */
+
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+/*
+ * computes a partial checksum, e.g. for TCP/UDP fragments
+ */
+
+/*
+ * unsigned int csum_partial(const unsigned char *buf, int len,
+ *                           unsigned int sum);
+ *    a2 = buf
+ *    a3 = len
+ *    a4 = sum
+ *
+ * This function assumes 2- or 4-byte alignment.  Other alignments will fail!
+ */
+
+/* ONES_ADD converts twos-complement math to ones-complement. */
+#define ONES_ADD(sum, val)	  \
+	add	sum, sum, val	; \
+	bgeu	sum, val, 99f	; \
+	addi	sum, sum, 1	; \
+99:				;
+
+.text
+ENTRY(csum_partial)
+
+	/*
+	 * Experiments with Ethernet and SLIP connections show that buf
+	 * is aligned on either a 2-byte or 4-byte boundary.
+	 */
+	abi_entry_default
+	extui	a5, a2, 0, 2
+	bnez	a5, 8f		/* branch if 2-byte aligned */
+	/* Fall-through on common case, 4-byte alignment */
+1:
+	srli	a5, a3, 5	/* 32-byte chunks */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a5, 2f
+#else
+	beqz	a5, 2f
+	slli	a5, a5, 5
+	add	a5, a5, a2	/* a5 = end of last 32-byte chunk */
+.Loop1:
+#endif
+	l32i	a6, a2, 0
+	l32i	a7, a2, 4
+	ONES_ADD(a4, a6)
+	ONES_ADD(a4, a7)
+	l32i	a6, a2, 8
+	l32i	a7, a2, 12
+	ONES_ADD(a4, a6)
+	ONES_ADD(a4, a7)
+	l32i	a6, a2, 16
+	l32i	a7, a2, 20
+	ONES_ADD(a4, a6)
+	ONES_ADD(a4, a7)
+	l32i	a6, a2, 24
+	l32i	a7, a2, 28
+	ONES_ADD(a4, a6)
+	ONES_ADD(a4, a7)
+	addi	a2, a2, 4*8
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a5, .Loop1
+#endif
+2:
+	extui	a5, a3, 2, 3	/* remaining 4-byte chunks */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a5, 3f
+#else
+	beqz	a5, 3f
+	slli	a5, a5, 2
+	add	a5, a5, a2	/* a5 = end of last 4-byte chunk */
+.Loop2:
+#endif
+	l32i	a6, a2, 0
+	ONES_ADD(a4, a6)
+	addi	a2, a2, 4
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a5, .Loop2
+#endif
+3:
+	_bbci.l	a3, 1, 5f	/* remaining 2-byte chunk */
+	l16ui	a6, a2, 0
+	ONES_ADD(a4, a6)
+	addi	a2, a2, 2
+5:
+	_bbci.l	a3, 0, 7f	/* remaining 1-byte chunk */
+6:	l8ui	a6, a2, 0
+#ifdef __XTENSA_EB__
+	slli	a6, a6, 8	/* load byte into bits 8..15 */
+#endif
+	ONES_ADD(a4, a6)
+7:
+	mov	a2, a4
+	abi_ret_default
+
+	/* uncommon case, buf is 2-byte aligned */
+8:
+	beqz	a3, 7b		/* branch if len == 0 */
+	beqi	a3, 1, 6b	/* branch if len == 1 */
+
+	extui	a5, a2, 0, 1
+	bnez	a5, 8f		/* branch if 1-byte aligned */
+
+	l16ui	a6, a2, 0	/* common case, len >= 2 */
+	ONES_ADD(a4, a6)
+	addi	a2, a2, 2	/* adjust buf */
+	addi	a3, a3, -2	/* adjust len */
+	j	1b		/* now buf is 4-byte aligned */
+
+	/* case: odd-byte aligned, len > 1
+	 * This case is dog slow, so don't give us an odd address.
+	 * (I don't think this ever happens, but just in case.)
+	 */
+8:
+	srli	a5, a3, 2	/* 4-byte chunks */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a5, 2f
+#else
+	beqz	a5, 2f
+	slli	a5, a5, 2
+	add	a5, a5, a2	/* a5 = end of last 4-byte chunk */
+.Loop3:
+#endif
+	l8ui	a6, a2, 0	/* bits 24..31 */
+	l16ui	a7, a2, 1	/* bits  8..23 */
+	l8ui	a8, a2, 3	/* bits  0.. 8 */
+#ifdef	__XTENSA_EB__
+	slli	a6, a6, 24
+#else
+	slli	a8, a8, 24
+#endif
+	slli	a7, a7, 8
+	or	a7, a7, a6
+	or	a7, a7, a8
+	ONES_ADD(a4, a7)
+	addi	a2, a2, 4
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a5, .Loop3
+#endif
+2:
+	_bbci.l	a3, 1, 3f	/* remaining 2-byte chunk, still odd addr */
+	l8ui	a6, a2, 0
+	l8ui	a7, a2, 1
+#ifdef	__XTENSA_EB__
+	slli	a6, a6, 8
+#else
+	slli	a7, a7, 8
+#endif
+	or	a7, a7, a6
+	ONES_ADD(a4, a7)
+	addi	a2, a2, 2
+3:
+	j	5b		/* branch to handle the remaining byte */
+
+ENDPROC(csum_partial)
+EXPORT_SYMBOL(csum_partial)
+
+/*
+ * Copy from ds while checksumming, otherwise like csum_partial
+ */
+
+/*
+unsigned int csum_partial_copy_generic (const char *src, char *dst, int len)
+	a2  = src
+	a3  = dst
+	a4  = len
+	a5  = sum
+	a8  = temp
+	a9  = temp
+	a10 = temp
+
+    This function is optimized for 4-byte aligned addresses.  Other
+    alignments work, but not nearly as efficiently.
+ */
+
+ENTRY(csum_partial_copy_generic)
+
+	abi_entry_default
+	movi	a5, -1
+	or	a10, a2, a3
+
+	/* We optimize the following alignment tests for the 4-byte
+	aligned case.  Two bbsi.l instructions might seem more optimal
+	(commented out below).  However, both labels 5: and 3: are out
+	of the imm8 range, so the assembler relaxes them into
+	equivalent bbci.l, j combinations, which is actually
+	slower. */
+
+	extui	a9, a10, 0, 2
+	beqz	a9, 1f		/* branch if both are 4-byte aligned */
+	bbsi.l	a10, 0, 5f	/* branch if one address is odd */
+	j	3f		/* one address is 2-byte aligned */
+
+/*	_bbsi.l	a10, 0, 5f */	/* branch if odd address */
+/*	_bbsi.l	a10, 1, 3f */	/* branch if 2-byte-aligned address */
+
+1:
+	/* src and dst are both 4-byte aligned */
+	srli	a10, a4, 5	/* 32-byte chunks */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a10, 2f
+#else
+	beqz	a10, 2f
+	slli	a10, a10, 5
+	add	a10, a10, a2	/* a10 = end of last 32-byte src chunk */
+.Loop5:
+#endif
+EX(10f)	l32i	a9, a2, 0
+EX(10f)	l32i	a8, a2, 4
+EX(10f)	s32i	a9, a3, 0
+EX(10f)	s32i	a8, a3, 4
+	ONES_ADD(a5, a9)
+	ONES_ADD(a5, a8)
+EX(10f)	l32i	a9, a2, 8
+EX(10f)	l32i	a8, a2, 12
+EX(10f)	s32i	a9, a3, 8
+EX(10f)	s32i	a8, a3, 12
+	ONES_ADD(a5, a9)
+	ONES_ADD(a5, a8)
+EX(10f)	l32i	a9, a2, 16
+EX(10f)	l32i	a8, a2, 20
+EX(10f)	s32i	a9, a3, 16
+EX(10f)	s32i	a8, a3, 20
+	ONES_ADD(a5, a9)
+	ONES_ADD(a5, a8)
+EX(10f)	l32i	a9, a2, 24
+EX(10f)	l32i	a8, a2, 28
+EX(10f)	s32i	a9, a3, 24
+EX(10f)	s32i	a8, a3, 28
+	ONES_ADD(a5, a9)
+	ONES_ADD(a5, a8)
+	addi	a2, a2, 32
+	addi	a3, a3, 32
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a10, .Loop5
+#endif
+2:
+	extui	a10, a4, 2, 3	/* remaining 4-byte chunks */
+	extui	a4, a4, 0, 2	/* reset len for general-case, 2-byte chunks */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a10, 3f
+#else
+	beqz	a10, 3f
+	slli	a10, a10, 2
+	add	a10, a10, a2	/* a10 = end of last 4-byte src chunk */
+.Loop6:
+#endif
+EX(10f)	l32i	a9, a2, 0
+EX(10f)	s32i	a9, a3, 0
+	ONES_ADD(a5, a9)
+	addi	a2, a2, 4
+	addi	a3, a3, 4
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a10, .Loop6
+#endif
+3:
+	/*
+	Control comes to here in two cases: (1) It may fall through
+	to here from the 4-byte alignment case to process, at most,
+	one 2-byte chunk.  (2) It branches to here from above if
+	either src or dst is 2-byte aligned, and we process all bytes
+	here, except for perhaps a trailing odd byte.  It's
+	inefficient, so align your addresses to 4-byte boundaries.
+
+	a2 = src
+	a3 = dst
+	a4 = len
+	a5 = sum
+	*/
+	srli	a10, a4, 1	/* 2-byte chunks */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a10, 4f
+#else
+	beqz	a10, 4f
+	slli	a10, a10, 1
+	add	a10, a10, a2	/* a10 = end of last 2-byte src chunk */
+.Loop7:
+#endif
+EX(10f)	l16ui	a9, a2, 0
+EX(10f)	s16i	a9, a3, 0
+	ONES_ADD(a5, a9)
+	addi	a2, a2, 2
+	addi	a3, a3, 2
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a10, .Loop7
+#endif
+4:
+	/* This section processes a possible trailing odd byte. */
+	_bbci.l	a4, 0, 8f	/* 1-byte chunk */
+EX(10f)	l8ui	a9, a2, 0
+EX(10f)	s8i	a9, a3, 0
+#ifdef __XTENSA_EB__
+	slli	a9, a9, 8	/* shift byte to bits 8..15 */
+#endif
+	ONES_ADD(a5, a9)
+8:
+	mov	a2, a5
+	abi_ret_default
+
+5:
+	/* Control branch to here when either src or dst is odd.  We
+	process all bytes using 8-bit accesses.  Grossly inefficient,
+	so don't feed us an odd address. */
+
+	srli	a10, a4, 1	/* handle in pairs for 16-bit csum */
+#if XCHAL_HAVE_LOOPS
+	loopgtz	a10, 6f
+#else
+	beqz	a10, 6f
+	slli	a10, a10, 1
+	add	a10, a10, a2	/* a10 = end of last odd-aligned, 2-byte src chunk */
+.Loop8:
+#endif
+EX(10f)	l8ui	a9, a2, 0
+EX(10f)	l8ui	a8, a2, 1
+EX(10f)	s8i	a9, a3, 0
+EX(10f)	s8i	a8, a3, 1
+#ifdef __XTENSA_EB__
+	slli	a9, a9, 8	/* combine into a single 16-bit value */
+#else				/* for checksum computation */
+	slli	a8, a8, 8
+#endif
+	or	a9, a9, a8
+	ONES_ADD(a5, a9)
+	addi	a2, a2, 2
+	addi	a3, a3, 2
+#if !XCHAL_HAVE_LOOPS
+	blt	a2, a10, .Loop8
+#endif
+6:
+	j	4b		/* process the possible trailing odd byte */
+
+ENDPROC(csum_partial_copy_generic)
+EXPORT_SYMBOL(csum_partial_copy_generic)
+
+
+# Exception handler:
+.section .fixup, "ax"
+10:
+	movi	a2, 0
+	abi_ret_default
+
+.previous

linux-7.2.3/arch/xtensa/lib/divsi3.S

@@ -0,0 +1,75 @@
+/* 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(__divsi3)
+
+	abi_entry_default
+#if XCHAL_HAVE_DIV32
+	quos	a2, a2, a3
+#else
+	xor	a7, a2, a3	/* sign = dividend ^ divisor */
+	do_abs	a6, a2, a4	/* udividend = abs (dividend) */
+	do_abs	a3, a3, a4	/* udivisor = abs (divisor) */
+	bltui	a3, 2, .Lle_one	/* check if udivisor <= 1 */
+	do_nsau	a5, a6, a2, a8	/* udividend_shift = nsau (udividend) */
+	do_nsau	a4, a3, a2, a8	/* udivisor_shift = nsau (udivisor) */
+	bgeu	a5, a4, .Lspecial
+
+	sub	a4, a4, a5	/* count = udivisor_shift - udividend_shift */
+	ssl	a4
+	sll	a3, a3		/* udivisor <<= count */
+	movi	a2, 0		/* quotient = 0 */
+
+	/* test-subtract-and-shift loop; one quotient bit on each iteration */
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lloopend
+#endif /* XCHAL_HAVE_LOOPS */
+.Lloop:
+	bltu	a6, a3, .Lzerobit
+	sub	a6, a6, a3
+	addi	a2, a2, 1
+.Lzerobit:
+	slli	a2, a2, 1
+	srli	a3, a3, 1
+#if !XCHAL_HAVE_LOOPS
+	addi	a4, a4, -1
+	bnez	a4, .Lloop
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lloopend:
+
+	bltu	a6, a3, .Lreturn
+	addi	a2, a2, 1	/* increment if udividend >= udivisor */
+.Lreturn:
+	neg	a5, a2
+	movltz	a2, a5, a7	/* return (sign < 0) ? -quotient : quotient */
+	abi_ret_default
+
+.Lle_one:
+	beqz	a3, .Lerror
+	neg	a2, a6		/* if udivisor == 1, then return... */
+	movgez	a2, a6, a7	/* (sign < 0) ? -udividend : udividend */
+	abi_ret_default
+
+.Lspecial:
+	bltu	a6, a3, .Lreturn0 /* if dividend < divisor, return 0 */
+	movi	a2, 1
+	movi	a4, -1
+	movltz	a2, a4, a7	/* else return (sign < 0) ? -1 : 1 */
+	abi_ret_default
+
+.Lerror:
+	/* Divide by zero: Use an illegal instruction to force an exception.
+	   The subsequent "DIV0" string can be recognized by the exception
+	   handler to identify the real cause of the exception.  */
+	ill
+	.ascii	"DIV0"
+
+.Lreturn0:
+	movi	a2, 0
+#endif /* XCHAL_HAVE_DIV32 */
+	abi_ret_default
+
+ENDPROC(__divsi3)
+EXPORT_SYMBOL(__divsi3)

linux-7.2.3/arch/xtensa/lib/lshrdi3.S

@@ -0,0 +1,29 @@
+/* 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>
+
+#ifdef __XTENSA_EB__
+#define uh a2
+#define ul a3
+#else
+#define uh a3
+#define ul a2
+#endif /* __XTENSA_EB__ */
+
+ENTRY(__lshrdi3)
+
+	abi_entry_default
+	ssr	a4
+	bgei	a4, 32, .Lhigh_only
+	src	ul, uh, ul
+	srl	uh, uh
+	abi_ret_default
+
+.Lhigh_only:
+	srl	ul, uh
+	movi	uh, 0
+	abi_ret_default
+
+ENDPROC(__lshrdi3)
+EXPORT_SYMBOL(__lshrdi3)

linux-7.2.3/arch/xtensa/lib/memcopy.S

@@ -0,0 +1,542 @@
+/*
+ * arch/xtensa/lib/hal/memcopy.S -- Core HAL library functions
+ * xthal_memcpy and xthal_bcopy
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2002 - 2012 Tensilica Inc.
+ */
+
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+/*
+ * void *memcpy(void *dst, const void *src, size_t len);
+ *
+ * This function is intended to do the same thing as the standard
+ * library function memcpy() for most cases.
+ * However, where the source and/or destination references
+ * an instruction RAM or ROM or a data RAM or ROM, that
+ * source and/or destination will always be accessed with
+ * 32-bit load and store instructions (as required for these
+ * types of devices).
+ *
+ * !!!!!!!  XTFIXME:
+ * !!!!!!!  Handling of IRAM/IROM has not yet
+ * !!!!!!!  been implemented.
+ *
+ * The (general case) algorithm is as follows:
+ *   If destination is unaligned, align it by conditionally
+ *     copying 1 and 2 bytes.
+ *   If source is aligned,
+ *     do 16 bytes with a loop, and then finish up with
+ *     8, 4, 2, and 1 byte copies conditional on the length;
+ *   else (if source is unaligned),
+ *     do the same, but use SRC to align the source data.
+ *   This code tries to use fall-through branches for the common
+ *     case of aligned source and destination and multiple
+ *     of 4 (or 8) length.
+ *
+ * Register use:
+ *	a0/ return address
+ *	a1/ stack pointer
+ *	a2/ return value
+ *	a3/ src
+ *	a4/ length
+ *	a5/ dst
+ *	a6/ tmp
+ *	a7/ tmp
+ *	a8/ tmp
+ *	a9/ tmp
+ *	a10/ tmp
+ *	a11/ tmp
+ */
+
+	.text
+
+/*
+ * Byte by byte copy
+ */
+	.align	4
+	.byte	0		# 1 mod 4 alignment for LOOPNEZ
+				# (0 mod 4 alignment for LBEG)
+.Lbytecopy:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lbytecopydone
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a4, .Lbytecopydone
+	add	a7, a3, a4	# a7 = end address for source
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lnextbyte:
+	l8ui	a6, a3, 0
+	addi	a3, a3, 1
+	s8i	a6, a5, 0
+	addi	a5, a5, 1
+#if !XCHAL_HAVE_LOOPS
+	bne	a3, a7, .Lnextbyte # continue loop if $a3:src != $a7:src_end
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lbytecopydone:
+	abi_ret_default
+
+/*
+ * Destination is unaligned
+ */
+
+	.align	4
+.Ldst1mod2:	# dst is only byte aligned
+	_bltui	a4, 7, .Lbytecopy	# do short copies byte by byte
+
+	# copy 1 byte
+	l8ui	a6, a3,  0
+	addi	a3, a3,  1
+	addi	a4, a4, -1
+	s8i	a6, a5,  0
+	addi	a5, a5,  1
+	_bbci.l	a5, 1, .Ldstaligned	# if dst is now aligned, then
+					# return to main algorithm
+.Ldst2mod4:	# dst 16-bit aligned
+	# copy 2 bytes
+	_bltui	a4, 6, .Lbytecopy	# do short copies byte by byte
+	l8ui	a6, a3,  0
+	l8ui	a7, a3,  1
+	addi	a3, a3,  2
+	addi	a4, a4, -2
+	s8i	a6, a5,  0
+	s8i	a7, a5,  1
+	addi	a5, a5,  2
+	j	.Ldstaligned	# dst is now aligned, return to main algorithm
+
+ENTRY(__memcpy)
+WEAK(memcpy)
+
+	abi_entry_default
+	# a2/ dst, a3/ src, a4/ len
+	mov	a5, a2		# copy dst so that a2 is return value
+.Lcommon:
+	_bbsi.l	a2, 0, .Ldst1mod2	# if dst is 1 mod 2
+	_bbsi.l	a2, 1, .Ldst2mod4	# if dst is 2 mod 4
+.Ldstaligned:	# return here from .Ldst?mod? once dst is aligned
+	srli	a7, a4, 4	# number of loop iterations with 16B
+				# per iteration
+	movi	a8, 3		# if source is not aligned,
+	_bany	a3, a8, .Lsrcunaligned	# then use shifting copy
+	/*
+	 * Destination and source are word-aligned, use word copy.
+	 */
+	# copy 16 bytes per iteration for word-aligned dst and word-aligned src
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .Loop1done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .Loop1done
+	slli	a8, a7, 4
+	add	a8, a8, a3	# a8 = end of last 16B source chunk
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop1:
+	l32i	a6, a3,  0
+	l32i	a7, a3,  4
+	s32i	a6, a5,  0
+	l32i	a6, a3,  8
+	s32i	a7, a5,  4
+	l32i	a7, a3, 12
+	s32i	a6, a5,  8
+	addi	a3, a3, 16
+	s32i	a7, a5, 12
+	addi	a5, a5, 16
+#if !XCHAL_HAVE_LOOPS
+	bne	a3, a8, .Loop1  # continue loop if a3:src != a8:src_end
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop1done:
+	bbci.l	a4, 3, .L2
+	# copy 8 bytes
+	l32i	a6, a3,  0
+	l32i	a7, a3,  4
+	addi	a3, a3,  8
+	s32i	a6, a5,  0
+	s32i	a7, a5,  4
+	addi	a5, a5,  8
+.L2:
+	bbsi.l	a4, 2, .L3
+	bbsi.l	a4, 1, .L4
+	bbsi.l	a4, 0, .L5
+	abi_ret_default
+.L3:
+	# copy 4 bytes
+	l32i	a6, a3,  0
+	addi	a3, a3,  4
+	s32i	a6, a5,  0
+	addi	a5, a5,  4
+	bbsi.l	a4, 1, .L4
+	bbsi.l	a4, 0, .L5
+	abi_ret_default
+.L4:
+	# copy 2 bytes
+	l16ui	a6, a3,  0
+	addi	a3, a3,  2
+	s16i	a6, a5,  0
+	addi	a5, a5,  2
+	bbsi.l	a4, 0, .L5
+	abi_ret_default
+.L5:
+	# copy 1 byte
+	l8ui	a6, a3,  0
+	s8i	a6, a5,  0
+	abi_ret_default
+
+/*
+ * Destination is aligned, Source is unaligned
+ */
+
+	.align	4
+.Lsrcunaligned:
+	_beqz	a4, .Ldone	# avoid loading anything for zero-length copies
+	# copy 16 bytes per iteration for word-aligned dst and unaligned src
+	__ssa8	a3		# set shift amount from byte offset
+
+/* set to 1 when running on ISS (simulator) with the
+   lint or ferret client, or 0 to save a few cycles */
+#define SIM_CHECKS_ALIGNMENT	1
+#if XCHAL_UNALIGNED_LOAD_EXCEPTION || SIM_CHECKS_ALIGNMENT
+	and	a11, a3, a8	# save unalignment offset for below
+	sub	a3, a3, a11	# align a3
+#endif
+	l32i	a6, a3, 0	# load first word
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .Loop2done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .Loop2done
+	slli	a10, a7, 4
+	add	a10, a10, a3	# a10 = end of last 16B source chunk
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop2:
+	l32i	a7, a3,  4
+	l32i	a8, a3,  8
+	__src_b	a6, a6, a7
+	s32i	a6, a5,  0
+	l32i	a9, a3, 12
+	__src_b	a7, a7, a8
+	s32i	a7, a5,  4
+	l32i	a6, a3, 16
+	__src_b	a8, a8, a9
+	s32i	a8, a5,  8
+	addi	a3, a3, 16
+	__src_b	a9, a9, a6
+	s32i	a9, a5, 12
+	addi	a5, a5, 16
+#if !XCHAL_HAVE_LOOPS
+	bne	a3, a10, .Loop2 # continue loop if a3:src != a10:src_end
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop2done:
+	bbci.l	a4, 3, .L12
+	# copy 8 bytes
+	l32i	a7, a3,  4
+	l32i	a8, a3,  8
+	__src_b	a6, a6, a7
+	s32i	a6, a5,  0
+	addi	a3, a3,  8
+	__src_b	a7, a7, a8
+	s32i	a7, a5,  4
+	addi	a5, a5,  8
+	mov	a6, a8
+.L12:
+	bbci.l	a4, 2, .L13
+	# copy 4 bytes
+	l32i	a7, a3,  4
+	addi	a3, a3,  4
+	__src_b	a6, a6, a7
+	s32i	a6, a5,  0
+	addi	a5, a5,  4
+	mov	a6, a7
+.L13:
+#if XCHAL_UNALIGNED_LOAD_EXCEPTION || SIM_CHECKS_ALIGNMENT
+	add	a3, a3, a11	# readjust a3 with correct misalignment
+#endif
+	bbsi.l	a4, 1, .L14
+	bbsi.l	a4, 0, .L15
+.Ldone:	abi_ret_default
+.L14:
+	# copy 2 bytes
+	l8ui	a6, a3,  0
+	l8ui	a7, a3,  1
+	addi	a3, a3,  2
+	s8i	a6, a5,  0
+	s8i	a7, a5,  1
+	addi	a5, a5,  2
+	bbsi.l	a4, 0, .L15
+	abi_ret_default
+.L15:
+	# copy 1 byte
+	l8ui	a6, a3,  0
+	s8i	a6, a5,  0
+	abi_ret_default
+
+ENDPROC(__memcpy)
+EXPORT_SYMBOL(__memcpy)
+EXPORT_SYMBOL(memcpy)
+
+/*
+ * void *memmove(void *dst, const void *src, size_t len);
+ *
+ * This function is intended to do the same thing as the standard
+ * library function memmove() for most cases.
+ * However, where the source and/or destination references
+ * an instruction RAM or ROM or a data RAM or ROM, that
+ * source and/or destination will always be accessed with
+ * 32-bit load and store instructions (as required for these
+ * types of devices).
+ *
+ * !!!!!!!  XTFIXME:
+ * !!!!!!!  Handling of IRAM/IROM has not yet
+ * !!!!!!!  been implemented.
+ *
+ * The (general case) algorithm is as follows:
+ *   If end of source doesn't overlap destination then use memcpy.
+ *   Otherwise do memcpy backwards.
+ *
+ * Register use:
+ *	a0/ return address
+ *	a1/ stack pointer
+ *	a2/ return value
+ *	a3/ src
+ *	a4/ length
+ *	a5/ dst
+ *	a6/ tmp
+ *	a7/ tmp
+ *	a8/ tmp
+ *	a9/ tmp
+ *	a10/ tmp
+ *	a11/ tmp
+ */
+
+/*
+ * Byte by byte copy
+ */
+	.align	4
+	.byte	0		# 1 mod 4 alignment for LOOPNEZ
+				# (0 mod 4 alignment for LBEG)
+.Lbackbytecopy:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lbackbytecopydone
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a4, .Lbackbytecopydone
+	sub	a7, a3, a4	# a7 = start address for source
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lbacknextbyte:
+	addi	a3, a3, -1
+	l8ui	a6, a3, 0
+	addi	a5, a5, -1
+	s8i	a6, a5, 0
+#if !XCHAL_HAVE_LOOPS
+	bne	a3, a7, .Lbacknextbyte # continue loop if
+				       # $a3:src != $a7:src_start
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lbackbytecopydone:
+	abi_ret_default
+
+/*
+ * Destination is unaligned
+ */
+
+	.align	4
+.Lbackdst1mod2:	# dst is only byte aligned
+	_bltui	a4, 7, .Lbackbytecopy	# do short copies byte by byte
+
+	# copy 1 byte
+	addi	a3, a3, -1
+	l8ui	a6, a3,  0
+	addi	a5, a5, -1
+	s8i	a6, a5,  0
+	addi	a4, a4, -1
+	_bbci.l	a5, 1, .Lbackdstaligned	# if dst is now aligned, then
+					# return to main algorithm
+.Lbackdst2mod4:	# dst 16-bit aligned
+	# copy 2 bytes
+	_bltui	a4, 6, .Lbackbytecopy	# do short copies byte by byte
+	addi	a3, a3, -2
+	l8ui	a6, a3,  0
+	l8ui	a7, a3,  1
+	addi	a5, a5, -2
+	s8i	a6, a5,  0
+	s8i	a7, a5,  1
+	addi	a4, a4, -2
+	j	.Lbackdstaligned	# dst is now aligned,
+					# return to main algorithm
+
+ENTRY(__memmove)
+WEAK(memmove)
+
+	abi_entry_default
+	# a2/ dst, a3/ src, a4/ len
+	mov	a5, a2		# copy dst so that a2 is return value
+.Lmovecommon:
+	sub	a6, a5, a3
+	bgeu	a6, a4, .Lcommon
+
+	add	a5, a5, a4
+	add	a3, a3, a4
+
+	_bbsi.l	a5, 0, .Lbackdst1mod2	# if dst is 1 mod 2
+	_bbsi.l	a5, 1, .Lbackdst2mod4	# if dst is 2 mod 4
+.Lbackdstaligned:	# return here from .Lbackdst?mod? once dst is aligned
+	srli	a7, a4, 4	# number of loop iterations with 16B
+				# per iteration
+	movi	a8, 3		# if source is not aligned,
+	_bany	a3, a8, .Lbacksrcunaligned	# then use shifting copy
+	/*
+	 * Destination and source are word-aligned, use word copy.
+	 */
+	# copy 16 bytes per iteration for word-aligned dst and word-aligned src
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .LbackLoop1done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .LbackLoop1done
+	slli	a8, a7, 4
+	sub	a8, a3, a8	# a8 = start of first 16B source chunk
+#endif /* !XCHAL_HAVE_LOOPS */
+.LbackLoop1:
+	addi	a3, a3, -16
+	l32i	a7, a3, 12
+	l32i	a6, a3,  8
+	addi	a5, a5, -16
+	s32i	a7, a5, 12
+	l32i	a7, a3,  4
+	s32i	a6, a5,  8
+	l32i	a6, a3,  0
+	s32i	a7, a5,  4
+	s32i	a6, a5,  0
+#if !XCHAL_HAVE_LOOPS
+	bne	a3, a8, .LbackLoop1  # continue loop if a3:src != a8:src_start
+#endif /* !XCHAL_HAVE_LOOPS */
+.LbackLoop1done:
+	bbci.l	a4, 3, .Lback2
+	# copy 8 bytes
+	addi	a3, a3, -8
+	l32i	a6, a3,  0
+	l32i	a7, a3,  4
+	addi	a5, a5, -8
+	s32i	a6, a5,  0
+	s32i	a7, a5,  4
+.Lback2:
+	bbsi.l	a4, 2, .Lback3
+	bbsi.l	a4, 1, .Lback4
+	bbsi.l	a4, 0, .Lback5
+	abi_ret_default
+.Lback3:
+	# copy 4 bytes
+	addi	a3, a3, -4
+	l32i	a6, a3,  0
+	addi	a5, a5, -4
+	s32i	a6, a5,  0
+	bbsi.l	a4, 1, .Lback4
+	bbsi.l	a4, 0, .Lback5
+	abi_ret_default
+.Lback4:
+	# copy 2 bytes
+	addi	a3, a3, -2
+	l16ui	a6, a3,  0
+	addi	a5, a5, -2
+	s16i	a6, a5,  0
+	bbsi.l	a4, 0, .Lback5
+	abi_ret_default
+.Lback5:
+	# copy 1 byte
+	addi	a3, a3, -1
+	l8ui	a6, a3,  0
+	addi	a5, a5, -1
+	s8i	a6, a5,  0
+	abi_ret_default
+
+/*
+ * Destination is aligned, Source is unaligned
+ */
+
+	.align	4
+.Lbacksrcunaligned:
+	_beqz	a4, .Lbackdone	# avoid loading anything for zero-length copies
+	# copy 16 bytes per iteration for word-aligned dst and unaligned src
+	__ssa8	a3		# set shift amount from byte offset
+#define SIM_CHECKS_ALIGNMENT	1	/* set to 1 when running on ISS with
+					 * the lint or ferret client, or 0
+					 * to save a few cycles */
+#if XCHAL_UNALIGNED_LOAD_EXCEPTION || SIM_CHECKS_ALIGNMENT
+	and	a11, a3, a8	# save unalignment offset for below
+	sub	a3, a3, a11	# align a3
+#endif
+	l32i	a6, a3, 0	# load first word
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .LbackLoop2done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .LbackLoop2done
+	slli	a10, a7, 4
+	sub	a10, a3, a10	# a10 = start of first 16B source chunk
+#endif /* !XCHAL_HAVE_LOOPS */
+.LbackLoop2:
+	addi	a3, a3, -16
+	l32i	a7, a3, 12
+	l32i	a8, a3,  8
+	addi	a5, a5, -16
+	__src_b	a6, a7, a6
+	s32i	a6, a5, 12
+	l32i	a9, a3,  4
+	__src_b	a7, a8, a7
+	s32i	a7, a5,  8
+	l32i	a6, a3,  0
+	__src_b	a8, a9, a8
+	s32i	a8, a5,  4
+	__src_b	a9, a6, a9
+	s32i	a9, a5,  0
+#if !XCHAL_HAVE_LOOPS
+	bne	a3, a10, .LbackLoop2 # continue loop if a3:src != a10:src_start
+#endif /* !XCHAL_HAVE_LOOPS */
+.LbackLoop2done:
+	bbci.l	a4, 3, .Lback12
+	# copy 8 bytes
+	addi	a3, a3, -8
+	l32i	a7, a3,  4
+	l32i	a8, a3,  0
+	addi	a5, a5, -8
+	__src_b	a6, a7, a6
+	s32i	a6, a5,  4
+	__src_b	a7, a8, a7
+	s32i	a7, a5,  0
+	mov	a6, a8
+.Lback12:
+	bbci.l	a4, 2, .Lback13
+	# copy 4 bytes
+	addi	a3, a3, -4
+	l32i	a7, a3,  0
+	addi	a5, a5, -4
+	__src_b	a6, a7, a6
+	s32i	a6, a5,  0
+	mov	a6, a7
+.Lback13:
+#if XCHAL_UNALIGNED_LOAD_EXCEPTION || SIM_CHECKS_ALIGNMENT
+	add	a3, a3, a11	# readjust a3 with correct misalignment
+#endif
+	bbsi.l	a4, 1, .Lback14
+	bbsi.l	a4, 0, .Lback15
+.Lbackdone:
+	abi_ret_default
+.Lback14:
+	# copy 2 bytes
+	addi	a3, a3, -2
+	l8ui	a6, a3,  0
+	l8ui	a7, a3,  1
+	addi	a5, a5, -2
+	s8i	a6, a5,  0
+	s8i	a7, a5,  1
+	bbsi.l	a4, 0, .Lback15
+	abi_ret_default
+.Lback15:
+	# copy 1 byte
+	addi	a3, a3, -1
+	addi	a5, a5, -1
+	l8ui	a6, a3,  0
+	s8i	a6, a5,  0
+	abi_ret_default
+
+ENDPROC(__memmove)
+EXPORT_SYMBOL(__memmove)
+EXPORT_SYMBOL(memmove)

linux-7.2.3/arch/xtensa/lib/memset.S

@@ -0,0 +1,155 @@
+/*
+ *  arch/xtensa/lib/memset.S
+ *
+ *  ANSI C standard library function memset
+ *  (Well, almost.  .fixup code might return zero.)
+ *
+ *  This file is subject to the terms and conditions of the GNU General
+ *  Public License.  See the file "COPYING" in the main directory of
+ *  this archive for more details.
+ *
+ *  Copyright (C) 2002 Tensilica Inc.
+ */
+
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+/*
+ * void *memset(void *dst, int c, size_t length)
+ *
+ * The algorithm is as follows:
+ *   Create a word with c in all byte positions
+ *   If the destination is aligned,
+ *     do 16B chucks with a loop, and then finish up with
+ *     8B, 4B, 2B, and 1B stores conditional on the length.
+ *   If destination is unaligned, align it by conditionally
+ *     setting 1B and 2B and then go to aligned case.
+ *   This code tries to use fall-through branches for the common
+ *     case of an aligned destination (except for the branches to
+ *     the alignment labels).
+ */
+
+.text
+ENTRY(__memset)
+WEAK(memset)
+
+	abi_entry_default
+	# a2/ dst, a3/ c, a4/ length
+	extui	a3, a3, 0, 8	# mask to just 8 bits
+	slli	a7, a3, 8	# duplicate character in all bytes of word
+	or	a3, a3, a7	# ...
+	slli	a7, a3, 16	# ...
+	or	a3, a3, a7	# ...
+	mov	a5, a2		# copy dst so that a2 is return value
+	movi	a6, 3		# for alignment tests
+	bany	a2, a6, .Ldstunaligned # if dst is unaligned
+.L0:	# return here from .Ldstunaligned when dst is aligned
+	srli	a7, a4, 4	# number of loop iterations with 16B
+				# per iteration
+	bnez	a4, .Laligned
+	abi_ret_default
+
+/*
+ * Destination is word-aligned.
+ */
+	# set 16 bytes per iteration for word-aligned dst
+	.align	4		# 1 mod 4 alignment for LOOPNEZ
+	.byte	0		# (0 mod 4 alignment for LBEG)
+.Laligned:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .Loop1done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .Loop1done
+	slli	a6, a7, 4
+	add	a6, a6, a5	# a6 = end of last 16B chunk
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop1:
+EX(10f) s32i	a3, a5,  0
+EX(10f) s32i	a3, a5,  4
+EX(10f) s32i	a3, a5,  8
+EX(10f) s32i	a3, a5, 12
+	addi	a5, a5, 16
+#if !XCHAL_HAVE_LOOPS
+	blt	a5, a6, .Loop1
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop1done:
+	bbci.l	a4, 3, .L2
+	# set 8 bytes
+EX(10f) s32i	a3, a5,  0
+EX(10f) s32i	a3, a5,  4
+	addi	a5, a5,  8
+.L2:
+	bbci.l	a4, 2, .L3
+	# set 4 bytes
+EX(10f) s32i	a3, a5,  0
+	addi	a5, a5,  4
+.L3:
+	bbci.l	a4, 1, .L4
+	# set 2 bytes
+EX(10f) s16i	a3, a5,  0
+	addi	a5, a5,  2
+.L4:
+	bbci.l	a4, 0, .L5
+	# set 1 byte
+EX(10f) s8i	a3, a5,  0
+.L5:
+.Lret1:
+	abi_ret_default
+
+/*
+ * Destination is unaligned
+ */
+
+.Ldstunaligned:
+	bltui	a4, 8, .Lbyteset	# do short copies byte by byte
+	bbci.l	a5, 0, .L20		# branch if dst alignment half-aligned
+	# dst is only byte aligned
+	# set 1 byte
+EX(10f) s8i	a3, a5,  0
+	addi	a5, a5,  1
+	addi	a4, a4, -1
+	# now retest if dst aligned
+	bbci.l	a5, 1, .L0	# if now aligned, return to main algorithm
+.L20:
+	# dst half-aligned
+	# set 2 bytes
+EX(10f) s16i	a3, a5,  0
+	addi	a5, a5,  2
+	addi	a4, a4, -2
+	j	.L0		# dst is now aligned, return to main algorithm
+
+/*
+ * Byte by byte set
+ */
+	.align	4
+	.byte	0		# 1 mod 4 alignment for LOOPNEZ
+				# (0 mod 4 alignment for LBEG)
+.Lbyteset:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lbytesetdone
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a4, .Lbytesetdone
+	add	a6, a5, a4	# a6 = ending address
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lbyteloop:
+EX(10f) s8i	a3, a5, 0
+	addi	a5, a5, 1
+#if !XCHAL_HAVE_LOOPS
+	blt	a5, a6, .Lbyteloop
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lbytesetdone:
+	abi_ret_default
+
+ENDPROC(__memset)
+EXPORT_SYMBOL(__memset)
+EXPORT_SYMBOL(memset)
+
+	.section .fixup, "ax"
+	.align	4
+
+/* We return zero if a failure occurred. */
+
+10:
+	movi	a2, 0
+	abi_ret_default

linux-7.2.3/arch/xtensa/lib/modsi3.S

@@ -0,0 +1,88 @@
+/* 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(__modsi3)
+
+	abi_entry_default
+#if XCHAL_HAVE_DIV32
+	rems	a2, a2, a3
+#else
+	mov	a7, a2		/* save original (signed) dividend */
+	do_abs	a2, a2, a4	/* udividend = abs (dividend) */
+	do_abs	a3, a3, a4	/* udivisor = abs (divisor) */
+	bltui	a3, 2, .Lle_one	/* check if udivisor <= 1 */
+	do_nsau	a5, a2, a6, a8	/* udividend_shift = nsau (udividend) */
+	do_nsau	a4, a3, a6, a8	/* udivisor_shift = nsau (udivisor) */
+	bgeu	a5, a4, .Lspecial
+
+	sub	a4, a4, a5	/* count = udivisor_shift - udividend_shift */
+	ssl	a4
+	sll	a3, a3		/* udivisor <<= count */
+
+	/* test-subtract-and-shift loop */
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lloopend
+#endif /* XCHAL_HAVE_LOOPS */
+.Lloop:
+	bltu	a2, a3, .Lzerobit
+	sub	a2, a2, a3
+.Lzerobit:
+	srli	a3, a3, 1
+#if !XCHAL_HAVE_LOOPS
+	addi	a4, a4, -1
+	bnez	a4, .Lloop
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lloopend:
+
+.Lspecial:
+	bltu	a2, a3, .Lreturn
+	sub	a2, a2, a3	/* subtract again if udividend >= udivisor */
+.Lreturn:
+	bgez	a7, .Lpositive
+	neg	a2, a2		/* if (dividend < 0), return -udividend */
+.Lpositive:
+	abi_ret_default
+
+.Lle_one:
+	bnez	a3, .Lreturn0
+
+	/* Divide by zero: Use an illegal instruction to force an exception.
+	   The subsequent "DIV0" string can be recognized by the exception
+	   handler to identify the real cause of the exception.  */
+	ill
+	.ascii	"DIV0"
+
+.Lreturn0:
+	movi	a2, 0
+#endif /* XCHAL_HAVE_DIV32 */
+	abi_ret_default
+
+ENDPROC(__modsi3)
+EXPORT_SYMBOL(__modsi3)
+
+#if !XCHAL_HAVE_NSA
+	.section .rodata
+	.align	4
+	.global	__nsau_data
+	.type	__nsau_data, @object
+__nsau_data:
+	.byte	8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4
+	.byte	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
+	.byte	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
+	.byte	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
+	.byte	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+	.byte	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+	.byte	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+	.byte	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.byte	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+	.size	__nsau_data, . - __nsau_data
+#endif /* !XCHAL_HAVE_NSA */

linux-7.2.3/arch/xtensa/lib/mulsi3.S

@@ -0,0 +1,134 @@
+/* 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>
+
+	.macro	do_addx2 dst, as, at, tmp
+#if XCHAL_HAVE_ADDX
+	addx2	\dst, \as, \at
+#else
+	slli	\tmp, \as, 1
+	add	\dst, \tmp, \at
+#endif
+	.endm
+
+	.macro	do_addx4 dst, as, at, tmp
+#if XCHAL_HAVE_ADDX
+	addx4	\dst, \as, \at
+#else
+	slli	\tmp, \as, 2
+	add	\dst, \tmp, \at
+#endif
+	.endm
+
+	.macro	do_addx8 dst, as, at, tmp
+#if XCHAL_HAVE_ADDX
+	addx8	\dst, \as, \at
+#else
+	slli	\tmp, \as, 3
+	add	\dst, \tmp, \at
+#endif
+	.endm
+
+ENTRY(__mulsi3)
+
+	abi_entry_default
+
+#if XCHAL_HAVE_MUL32
+	mull	a2, a2, a3
+
+#elif XCHAL_HAVE_MUL16
+	or	a4, a2, a3
+	srai	a4, a4, 16
+	bnez	a4, .LMUL16
+	mul16u	a2, a2, a3
+	abi_ret_default
+.LMUL16:
+	srai	a4, a2, 16
+	srai	a5, a3, 16
+	mul16u	a7, a4, a3
+	mul16u	a6, a5, a2
+	mul16u	a4, a2, a3
+	add	a7, a7, a6
+	slli	a7, a7, 16
+	add	a2, a7, a4
+
+#elif XCHAL_HAVE_MAC16
+	mul.aa.hl a2, a3
+	mula.aa.lh a2, a3
+	rsr	a5, ACCLO
+	umul.aa.ll a2, a3
+	rsr	a4, ACCLO
+	slli	a5, a5, 16
+	add	a2, a4, a5
+
+#else /* !MUL32 && !MUL16 && !MAC16 */
+
+	/* Multiply one bit at a time, but unroll the loop 4x to better
+	   exploit the addx instructions and avoid overhead.
+	   Peel the first iteration to save a cycle on init.  */
+
+	/* Avoid negative numbers.  */
+	xor	a5, a2, a3	/* Top bit is 1 if one input is negative.  */
+	do_abs	a3, a3, a6
+	do_abs	a2, a2, a6
+
+	/* Swap so the second argument is smaller.  */
+	sub	a7, a2, a3
+	mov	a4, a3
+	movgez	a4, a2, a7	/* a4 = max (a2, a3) */
+	movltz	a3, a2, a7	/* a3 = min (a2, a3) */
+
+	movi	a2, 0
+	extui	a6, a3, 0, 1
+	movnez	a2, a4, a6
+
+	do_addx2 a7, a4, a2, a7
+	extui	a6, a3, 1, 1
+	movnez	a2, a7, a6
+
+	do_addx4 a7, a4, a2, a7
+	extui	a6, a3, 2, 1
+	movnez	a2, a7, a6
+
+	do_addx8 a7, a4, a2, a7
+	extui	a6, a3, 3, 1
+	movnez	a2, a7, a6
+
+	bgeui	a3, 16, .Lmult_main_loop
+	neg	a3, a2
+	movltz	a2, a3, a5
+	abi_ret_default
+
+	.align	4
+.Lmult_main_loop:
+	srli	a3, a3, 4
+	slli	a4, a4, 4
+
+	add	a7, a4, a2
+	extui	a6, a3, 0, 1
+	movnez	a2, a7, a6
+
+	do_addx2 a7, a4, a2, a7
+	extui	a6, a3, 1, 1
+	movnez	a2, a7, a6
+
+	do_addx4 a7, a4, a2, a7
+	extui	a6, a3, 2, 1
+	movnez	a2, a7, a6
+
+	do_addx8 a7, a4, a2, a7
+	extui	a6, a3, 3, 1
+	movnez	a2, a7, a6
+
+	bgeui	a3, 16, .Lmult_main_loop
+
+	neg	a3, a2
+	movltz	a2, a3, a5
+
+#endif /* !MUL32 && !MUL16 && !MAC16 */
+
+	abi_ret_default
+
+ENDPROC(__mulsi3)
+EXPORT_SYMBOL(__mulsi3)

linux-7.2.3/arch/xtensa/lib/pci-auto.c

@@ -0,0 +1,318 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * arch/xtensa/lib/pci-auto.c
+ *
+ * PCI autoconfiguration library
+ *
+ * Copyright (C) 2001 - 2005 Tensilica Inc.
+ *
+ * Chris Zankel <zankel@tensilica.com, cez@zankel.net>
+ *
+ * Based on work from Matt Porter <mporter@mvista.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+
+#include <asm/pci-bridge.h>
+
+
+/*
+ *
+ * Setting up a PCI
+ *
+ * pci_ctrl->first_busno = <first bus number (0)>
+ * pci_ctrl->last_busno = <last bus number (0xff)>
+ * pci_ctrl->ops = <PCI config operations>
+ * pci_ctrl->map_irq = <function to return the interrupt number for a device>
+ *
+ * pci_ctrl->io_space.start = <IO space start address (PCI view)>
+ * pci_ctrl->io_space.end = <IO space end address (PCI view)>
+ * pci_ctrl->io_space.base = <IO space offset: address 0 from CPU space>
+ * pci_ctrl->mem_space.start = <MEM space start address (PCI view)>
+ * pci_ctrl->mem_space.end = <MEM space end address (PCI view)>
+ * pci_ctrl->mem_space.base = <MEM space offset: address 0 from CPU space>
+ *
+ * pcibios_init_resource(&pci_ctrl->io_resource, <IO space start>,
+ * 			 <IO space end>, IORESOURCE_IO, "PCI host bridge");
+ * pcibios_init_resource(&pci_ctrl->mem_resources[0], <MEM space start>,
+ * 			 <MEM space end>, IORESOURCE_MEM, "PCI host bridge");
+ *
+ * pci_ctrl->last_busno = pciauto_bus_scan(pci_ctrl,pci_ctrl->first_busno);
+ *
+ * int __init pciauto_bus_scan(struct pci_controller *pci_ctrl, int current_bus)
+ *
+ */
+
+static int pciauto_upper_iospc;
+static int pciauto_upper_memspc;
+
+static struct pci_dev pciauto_dev;
+static struct pci_bus pciauto_bus;
+
+/*
+ * Helper functions
+ */
+
+/* Initialize the bars of a PCI device.  */
+
+static void __init
+pciauto_setup_bars(struct pci_dev *dev, int bar_limit)
+{
+	int bar_size;
+	int bar, bar_nr;
+	int *upper_limit;
+	int found_mem64 = 0;
+
+	for (bar = PCI_BASE_ADDRESS_0, bar_nr = 0;
+	     bar <= bar_limit;
+	     bar+=4, bar_nr++)
+	{
+		/* Tickle the BAR and get the size */
+		pci_write_config_dword(dev, bar, 0xffffffff);
+		pci_read_config_dword(dev, bar, &bar_size);
+
+		/* If BAR is not implemented go to the next BAR */
+		if (!bar_size)
+			continue;
+
+		/* Check the BAR type and set our address mask */
+		if (bar_size & PCI_BASE_ADDRESS_SPACE_IO)
+		{
+			bar_size &= PCI_BASE_ADDRESS_IO_MASK;
+			upper_limit = &pciauto_upper_iospc;
+			pr_debug("PCI Autoconfig: BAR %d, I/O, ", bar_nr);
+		}
+		else
+		{
+			if ((bar_size & PCI_BASE_ADDRESS_MEM_TYPE_MASK) ==
+			    PCI_BASE_ADDRESS_MEM_TYPE_64)
+				found_mem64 = 1;
+
+			bar_size &= PCI_BASE_ADDRESS_MEM_MASK;
+			upper_limit = &pciauto_upper_memspc;
+			pr_debug("PCI Autoconfig: BAR %d, Mem, ", bar_nr);
+		}
+
+		/* Allocate a base address (bar_size is negative!) */
+		*upper_limit = (*upper_limit + bar_size) & bar_size;
+
+		/* Write it out and update our limit */
+		pci_write_config_dword(dev, bar, *upper_limit);
+
+		/*
+		 * If we are a 64-bit decoder then increment to the
+		 * upper 32 bits of the bar and force it to locate
+		 * in the lower 4GB of memory.
+		 */
+
+		if (found_mem64)
+			pci_write_config_dword(dev, (bar+=4), 0x00000000);
+
+		pr_debug("size=0x%x, address=0x%x\n",
+			 ~bar_size + 1, *upper_limit);
+	}
+}
+
+/* Initialize the interrupt number. */
+
+static void __init
+pciauto_setup_irq(struct pci_controller* pci_ctrl,struct pci_dev *dev,int devfn)
+{
+	u8 pin;
+	int irq = 0;
+
+	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+
+	/* Fix illegal pin numbers. */
+
+	if (pin == 0 || pin > 4)
+		pin = 1;
+
+	if (pci_ctrl->map_irq)
+		irq = pci_ctrl->map_irq(dev, PCI_SLOT(devfn), pin);
+
+	if (irq == -1)
+		irq = 0;
+
+	pr_debug("PCI Autoconfig: Interrupt %d, pin %d\n", irq, pin);
+
+	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
+}
+
+
+static void __init
+pciauto_prescan_setup_bridge(struct pci_dev *dev, int current_bus,
+			     int sub_bus, int *iosave, int *memsave)
+{
+	/* Configure bus number registers */
+	pci_write_config_byte(dev, PCI_PRIMARY_BUS, current_bus);
+	pci_write_config_byte(dev, PCI_SECONDARY_BUS, sub_bus + 1);
+	pci_write_config_byte(dev, PCI_SUBORDINATE_BUS,	0xff);
+
+	/* Round memory allocator to 1MB boundary */
+	pciauto_upper_memspc &= ~(0x100000 - 1);
+	*memsave = pciauto_upper_memspc;
+
+	/* Round I/O allocator to 4KB boundary */
+	pciauto_upper_iospc &= ~(0x1000 - 1);
+	*iosave = pciauto_upper_iospc;
+
+	/* Set up memory and I/O filter limits, assume 32-bit I/O space */
+	pci_write_config_word(dev, PCI_MEMORY_LIMIT,
+			      ((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
+	pci_write_config_byte(dev, PCI_IO_LIMIT,
+			      ((pciauto_upper_iospc - 1) & 0x0000f000) >> 8);
+	pci_write_config_word(dev, PCI_IO_LIMIT_UPPER16,
+			      ((pciauto_upper_iospc - 1) & 0xffff0000) >> 16);
+}
+
+static void __init
+pciauto_postscan_setup_bridge(struct pci_dev *dev, int current_bus, int sub_bus,
+			      int *iosave, int *memsave)
+{
+	int cmdstat;
+
+	/* Configure bus number registers */
+	pci_write_config_byte(dev, PCI_SUBORDINATE_BUS,	sub_bus);
+
+	/*
+	 * Round memory allocator to 1MB boundary.
+	 * If no space used, allocate minimum.
+	 */
+	pciauto_upper_memspc &= ~(0x100000 - 1);
+	if (*memsave == pciauto_upper_memspc)
+		pciauto_upper_memspc -= 0x00100000;
+
+	pci_write_config_word(dev, PCI_MEMORY_BASE, pciauto_upper_memspc >> 16);
+
+	/* Allocate 1MB for pre-fretch */
+	pci_write_config_word(dev, PCI_PREF_MEMORY_LIMIT,
+			      ((pciauto_upper_memspc - 1) & 0xfff00000) >> 16);
+
+	pciauto_upper_memspc -= 0x100000;
+
+	pci_write_config_word(dev, PCI_PREF_MEMORY_BASE,
+			      pciauto_upper_memspc >> 16);
+
+	/* Round I/O allocator to 4KB boundary */
+	pciauto_upper_iospc &= ~(0x1000 - 1);
+	if (*iosave == pciauto_upper_iospc)
+		pciauto_upper_iospc -= 0x1000;
+
+	pci_write_config_byte(dev, PCI_IO_BASE,
+			      (pciauto_upper_iospc & 0x0000f000) >> 8);
+	pci_write_config_word(dev, PCI_IO_BASE_UPPER16,
+			      pciauto_upper_iospc >> 16);
+
+	/* Enable memory and I/O accesses, enable bus master */
+	pci_read_config_dword(dev, PCI_COMMAND, &cmdstat);
+	pci_write_config_dword(dev, PCI_COMMAND,
+			       cmdstat |
+			       PCI_COMMAND_IO |
+			       PCI_COMMAND_MEMORY |
+			       PCI_COMMAND_MASTER);
+}
+
+/*
+ * Scan the current PCI bus.
+ */
+
+
+int __init pciauto_bus_scan(struct pci_controller *pci_ctrl, int current_bus)
+{
+	int sub_bus, pci_devfn, pci_class, cmdstat;
+	unsigned short vid;
+	unsigned char header_type;
+	struct pci_dev *dev = &pciauto_dev;
+	bool found_multi = false;
+
+	pciauto_dev.bus = &pciauto_bus;
+	pciauto_dev.sysdata = pci_ctrl;
+	pciauto_bus.ops = pci_ctrl->ops;
+
+	/*
+	 * Fetch our I/O and memory space upper boundaries used
+	 * to allocated base addresses on this pci_controller.
+	 */
+
+	if (current_bus == pci_ctrl->first_busno)
+	{
+		pciauto_upper_iospc = pci_ctrl->io_resource.end + 1;
+		pciauto_upper_memspc = pci_ctrl->mem_resources[0].end + 1;
+	}
+
+	sub_bus = current_bus;
+
+	for (pci_devfn = 0; pci_devfn < 0xff; pci_devfn++)
+	{
+		/* Skip our host bridge */
+		if ((current_bus == pci_ctrl->first_busno) && (pci_devfn == 0))
+			continue;
+
+		if (PCI_FUNC(pci_devfn) && !found_multi)
+			continue;
+
+		pciauto_bus.number = current_bus;
+		pciauto_dev.devfn = pci_devfn;
+
+		/* If config space read fails from this device, move on */
+		if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type))
+			continue;
+
+		if (!PCI_FUNC(pci_devfn))
+			found_multi = FIELD_GET(PCI_HEADER_TYPE_MFD, header_type);
+		pci_read_config_word(dev, PCI_VENDOR_ID, &vid);
+
+		if (vid == 0xffff || vid == 0x0000) {
+			found_multi = false;
+			continue;
+		}
+
+		pci_read_config_dword(dev, PCI_CLASS_REVISION, &pci_class);
+
+		if ((pci_class >> 16) == PCI_CLASS_BRIDGE_PCI) {
+
+			int iosave, memsave;
+
+			pr_debug("PCI Autoconfig: Found P2P bridge, device %d\n",
+				 PCI_SLOT(pci_devfn));
+
+			/* Allocate PCI I/O and/or memory space */
+			pciauto_setup_bars(dev, PCI_BASE_ADDRESS_1);
+
+			pciauto_prescan_setup_bridge(dev, current_bus, sub_bus,
+					&iosave, &memsave);
+			sub_bus = pciauto_bus_scan(pci_ctrl, sub_bus+1);
+			pciauto_postscan_setup_bridge(dev, current_bus, sub_bus,
+					&iosave, &memsave);
+			pciauto_bus.number = current_bus;
+
+			continue;
+
+		}
+
+		/*
+		 * Found a peripheral, enable some standard
+		 * settings
+		 */
+
+		pci_read_config_dword(dev, PCI_COMMAND,	&cmdstat);
+		pci_write_config_dword(dev, PCI_COMMAND,
+				cmdstat |
+					PCI_COMMAND_IO |
+					PCI_COMMAND_MEMORY |
+					PCI_COMMAND_MASTER);
+		pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0x80);
+
+		/* Allocate PCI I/O and/or memory space */
+		pr_debug("PCI Autoconfig: Found Bus %d, Device %d, Function %d\n",
+			 current_bus, PCI_SLOT(pci_devfn), PCI_FUNC(pci_devfn));
+
+		pciauto_setup_bars(dev, PCI_BASE_ADDRESS_5);
+		pciauto_setup_irq(pci_ctrl, dev, pci_devfn);
+	}
+	return sub_bus;
+}

linux-7.2.3/arch/xtensa/lib/strncpy_user.S

@@ -0,0 +1,217 @@
+/*
+ *  arch/xtensa/lib/strncpy_user.S
+ *
+ *  This file is subject to the terms and conditions of the GNU General
+ *  Public License.  See the file "COPYING" in the main directory of
+ *  this archive for more details.
+ *
+ *  Returns: -EFAULT if exception before terminator, N if the entire
+ *  buffer filled, else strlen.
+ *
+ *  Copyright (C) 2002 Tensilica Inc.
+ */
+
+#include <linux/errno.h>
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+/*
+ * char *__strncpy_user(char *dst, const char *src, size_t len)
+ */
+
+#ifdef __XTENSA_EB__
+# define MASK0 0xff000000
+# define MASK1 0x00ff0000
+# define MASK2 0x0000ff00
+# define MASK3 0x000000ff
+#else
+# define MASK0 0x000000ff
+# define MASK1 0x0000ff00
+# define MASK2 0x00ff0000
+# define MASK3 0xff000000
+#endif
+
+# Register use
+#   a0/ return address
+#   a1/ stack pointer
+#   a2/ return value
+#   a3/ src
+#   a4/ len
+#   a5/ mask0
+#   a6/ mask1
+#   a7/ mask2
+#   a8/ mask3
+#   a9/ tmp
+#   a10/ tmp
+#   a11/ dst
+
+.text
+ENTRY(__strncpy_user)
+
+	abi_entry_default
+	# a2/ dst, a3/ src, a4/ len
+	mov	a11, a2		# leave dst in return value register
+	beqz	a4, .Lret	# if len is zero
+	movi	a5, MASK0	# mask for byte 0
+	movi	a6, MASK1	# mask for byte 1
+	movi	a7, MASK2	# mask for byte 2
+	movi	a8, MASK3	# mask for byte 3
+	bbsi.l	a3, 0, .Lsrc1mod2 # if only  8-bit aligned
+	bbsi.l	a3, 1, .Lsrc2mod4 # if only 16-bit aligned
+.Lsrcaligned:	# return here when src is word-aligned
+	srli	a10, a4, 2	# number of loop iterations with 4B per loop
+	movi	a9, 3
+	bnone	a11, a9, .Laligned
+	j	.Ldstunaligned
+
+.Lsrc1mod2:	# src address is odd
+EX(11f)	l8ui	a9, a3, 0		# get byte 0
+	addi	a3, a3, 1		# advance src pointer
+EX(10f)	s8i	a9, a11, 0		# store byte 0
+	beqz	a9, .Lret		# if byte 0 is zero
+	addi	a11, a11, 1		# advance dst pointer
+	addi	a4, a4, -1		# decrement len
+	beqz	a4, .Lret		# if len is zero
+	bbci.l	a3, 1, .Lsrcaligned	# if src is now word-aligned
+
+.Lsrc2mod4:	# src address is 2 mod 4
+EX(11f)	l8ui	a9, a3, 0		# get byte 0
+	/* 1-cycle interlock */
+EX(10f)	s8i	a9, a11, 0		# store byte 0
+	beqz	a9, .Lret		# if byte 0 is zero
+	addi	a11, a11, 1		# advance dst pointer
+	addi	a4, a4, -1		# decrement len
+	beqz	a4, .Lret		# if len is zero
+EX(11f)	l8ui	a9, a3, 1		# get byte 0
+	addi	a3, a3, 2		# advance src pointer
+EX(10f)	s8i	a9, a11, 0		# store byte 0
+	beqz	a9, .Lret		# if byte 0 is zero
+	addi	a11, a11, 1		# advance dst pointer
+	addi	a4, a4, -1		# decrement len
+	bnez	a4, .Lsrcaligned	# if len is nonzero
+.Lret:
+	sub	a2, a11, a2		# compute strlen
+	abi_ret_default
+
+/*
+ * dst is word-aligned, src is word-aligned
+ */
+	.align	4		# 1 mod 4 alignment for LOOPNEZ
+	.byte	0		# (0 mod 4 alignment for LBEG)
+.Laligned:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a10, .Loop1done
+#else
+	beqz	a10, .Loop1done
+	slli	a10, a10, 2
+	add	a10, a10, a11	# a10 = end of last 4B chunck
+#endif
+.Loop1:
+EX(11f)	l32i	a9, a3, 0		# get word from src
+	addi	a3, a3, 4		# advance src pointer
+	bnone	a9, a5, .Lz0		# if byte 0 is zero
+	bnone	a9, a6, .Lz1		# if byte 1 is zero
+	bnone	a9, a7, .Lz2		# if byte 2 is zero
+EX(10f)	s32i	a9, a11, 0		# store word to dst
+	bnone	a9, a8, .Lz3		# if byte 3 is zero
+	addi	a11, a11, 4		# advance dst pointer
+#if !XCHAL_HAVE_LOOPS
+	blt	a11, a10, .Loop1
+#endif
+
+.Loop1done:
+	bbci.l	a4, 1, .L100
+	# copy 2 bytes
+EX(11f)	l16ui	a9, a3, 0
+	addi	a3, a3, 2		# advance src pointer
+#ifdef __XTENSA_EB__
+	bnone	a9, a7, .Lz0		# if byte 2 is zero
+	bnone	a9, a8, .Lz1		# if byte 3 is zero
+#else
+	bnone	a9, a5, .Lz0		# if byte 0 is zero
+	bnone	a9, a6, .Lz1		# if byte 1 is zero
+#endif
+EX(10f)	s16i	a9, a11, 0
+	addi	a11, a11, 2		# advance dst pointer
+.L100:
+	bbci.l	a4, 0, .Lret
+EX(11f)	l8ui	a9, a3, 0
+	/* slot */
+EX(10f)	s8i	a9, a11, 0
+	beqz	a9, .Lret		# if byte is zero
+	addi	a11, a11, 1-3		# advance dst ptr 1, but also cancel
+					# the effect of adding 3 in .Lz3 code
+	/* fall thru to .Lz3 and "retw" */
+
+.Lz3:	# byte 3 is zero
+	addi	a11, a11, 3		# advance dst pointer
+	sub	a2, a11, a2		# compute strlen
+	abi_ret_default
+.Lz0:	# byte 0 is zero
+#ifdef __XTENSA_EB__
+	movi	a9, 0
+#endif /* __XTENSA_EB__ */
+EX(10f)	s8i	a9, a11, 0
+	sub	a2, a11, a2		# compute strlen
+	abi_ret_default
+.Lz1:	# byte 1 is zero
+#ifdef __XTENSA_EB__
+	extui   a9, a9, 16, 16
+#endif /* __XTENSA_EB__ */
+EX(10f)	s16i	a9, a11, 0
+	addi	a11, a11, 1		# advance dst pointer
+	sub	a2, a11, a2		# compute strlen
+	abi_ret_default
+.Lz2:	# byte 2 is zero
+#ifdef __XTENSA_EB__
+	extui   a9, a9, 16, 16
+#endif /* __XTENSA_EB__ */
+EX(10f)	s16i	a9, a11, 0
+	movi	a9, 0
+EX(10f)	s8i	a9, a11, 2
+	addi	a11, a11, 2		# advance dst pointer
+	sub	a2, a11, a2		# compute strlen
+	abi_ret_default
+
+	.align	4		# 1 mod 4 alignment for LOOPNEZ
+	.byte	0		# (0 mod 4 alignment for LBEG)
+.Ldstunaligned:
+/*
+ * for now just use byte copy loop
+ */
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lunalignedend
+#else
+	beqz	a4, .Lunalignedend
+	add	a10, a11, a4		# a10 = ending address
+#endif /* XCHAL_HAVE_LOOPS */
+.Lnextbyte:
+EX(11f)	l8ui	a9, a3, 0
+	addi	a3, a3, 1
+EX(10f)	s8i	a9, a11, 0
+	beqz	a9, .Lunalignedend
+	addi	a11, a11, 1
+#if !XCHAL_HAVE_LOOPS
+	blt	a11, a10, .Lnextbyte
+#endif
+
+.Lunalignedend:
+	sub	a2, a11, a2		# compute strlen
+	abi_ret_default
+
+ENDPROC(__strncpy_user)
+EXPORT_SYMBOL(__strncpy_user)
+
+	.section .fixup, "ax"
+	.align	4
+
+	/* For now, just return -EFAULT.  Future implementations might
+	 * like to clear remaining kernel space, like the fixup
+	 * implementation in memset().  Thus, we differentiate between
+	 * load/store fixups. */
+
+10:
+11:
+	movi	a2, -EFAULT
+	abi_ret_default

linux-7.2.3/arch/xtensa/lib/strnlen_user.S

@@ -0,0 +1,142 @@
+/*
+ *  arch/xtensa/lib/strnlen_user.S
+ *
+ *  This file is subject to the terms and conditions of the GNU General
+ *  Public License.  See the file "COPYING" in the main directory of
+ *  this archive for more details.
+ *
+ *  Returns strnlen, including trailing zero terminator.
+ *  Zero indicates error.
+ *
+ *  Copyright (C) 2002 Tensilica Inc.
+ */
+
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+/*
+ * size_t __strnlen_user(const char *s, size_t len)
+ */
+
+#ifdef __XTENSA_EB__
+# define MASK0 0xff000000
+# define MASK1 0x00ff0000
+# define MASK2 0x0000ff00
+# define MASK3 0x000000ff
+#else
+# define MASK0 0x000000ff
+# define MASK1 0x0000ff00
+# define MASK2 0x00ff0000
+# define MASK3 0xff000000
+#endif
+
+# Register use:
+#   a2/ src
+#   a3/ len
+#   a4/ tmp
+#   a5/ mask0
+#   a6/ mask1
+#   a7/ mask2
+#   a8/ mask3
+#   a9/ tmp
+#   a10/ tmp
+
+.text
+ENTRY(__strnlen_user)
+
+	abi_entry_default
+	# a2/ s, a3/ len
+	addi	a4, a2, -4	# because we overincrement at the end;
+				# we compensate with load offsets of 4
+	movi	a5, MASK0	# mask for byte 0
+	movi	a6, MASK1	# mask for byte 1
+	movi	a7, MASK2	# mask for byte 2
+	movi	a8, MASK3	# mask for byte 3
+	bbsi.l	a2, 0, .L1mod2	# if only  8-bit aligned
+	bbsi.l	a2, 1, .L2mod4	# if only 16-bit aligned
+
+/*
+ * String is word-aligned.
+ */
+.Laligned:
+	srli	a10, a3, 2	# number of loop iterations with 4B per loop
+#if XCHAL_HAVE_LOOPS
+	loopnez	a10, .Ldone
+#else
+	beqz	a10, .Ldone
+	slli	a10, a10, 2
+	add	a10, a10, a4	# a10 = end of last 4B chunk
+#endif /* XCHAL_HAVE_LOOPS */
+.Loop:
+EX(10f)	l32i	a9, a4, 4		# get next word of string
+	addi	a4, a4, 4		# advance string pointer
+	bnone	a9, a5, .Lz0		# if byte 0 is zero
+	bnone	a9, a6, .Lz1		# if byte 1 is zero
+	bnone	a9, a7, .Lz2		# if byte 2 is zero
+	bnone	a9, a8, .Lz3		# if byte 3 is zero
+#if !XCHAL_HAVE_LOOPS
+	blt	a4, a10, .Loop
+#endif
+
+.Ldone:
+EX(10f)	l32i	a9, a4, 4	# load 4 bytes for remaining checks
+
+	bbci.l	a3, 1, .L100
+	# check two more bytes (bytes 0, 1 of word)
+	addi	a4, a4, 2	# advance string pointer
+	bnone	a9, a5, .Lz0	# if byte 0 is zero
+	bnone	a9, a6, .Lz1	# if byte 1 is zero
+.L100:
+	bbci.l	a3, 0, .L101
+	# check one more byte (byte 2 of word)
+	# Actually, we don't need to check.  Zero or nonzero, we'll add one.
+	# Do not add an extra one for the NULL terminator since we have
+	#  exhausted the original len parameter.
+	addi	a4, a4, 1	# advance string pointer
+.L101:
+	sub	a2, a4, a2	# compute length
+	abi_ret_default
+
+# NOTE that in several places below, we point to the byte just after
+# the zero byte in order to include the NULL terminator in the count.
+
+.Lz3:	# byte 3 is zero
+	addi	a4, a4, 3	# point to zero byte
+.Lz0:	# byte 0 is zero
+	addi	a4, a4, 1	# point just beyond zero byte
+	sub	a2, a4, a2	# subtract to get length
+	abi_ret_default
+.Lz1:	# byte 1 is zero
+	addi	a4, a4, 1+1	# point just beyond zero byte
+	sub	a2, a4, a2	# subtract to get length
+	abi_ret_default
+.Lz2:	# byte 2 is zero
+	addi	a4, a4, 2+1	# point just beyond zero byte
+	sub	a2, a4, a2	# subtract to get length
+	abi_ret_default
+
+.L1mod2:	# address is odd
+EX(10f)	l8ui	a9, a4, 4		# get byte 0
+	addi	a4, a4, 1		# advance string pointer
+	beqz	a9, .Lz3		# if byte 0 is zero
+	bbci.l	a4, 1, .Laligned	# if string pointer is now word-aligned
+
+.L2mod4:	# address is 2 mod 4
+	addi	a4, a4, 2	# advance ptr for aligned access
+EX(10f)	l32i	a9, a4, 0	# get word with first two bytes of string
+	bnone	a9, a7, .Lz2	# if byte 2 (of word, not string) is zero
+	bany	a9, a8, .Laligned # if byte 3 (of word, not string) is nonzero
+	# byte 3 is zero
+	addi	a4, a4, 3+1	# point just beyond zero byte
+	sub	a2, a4, a2	# subtract to get length
+	abi_ret_default
+
+ENDPROC(__strnlen_user)
+EXPORT_SYMBOL(__strnlen_user)
+
+	.section .fixup, "ax"
+	.align	4
+10:
+	movi	a2, 0
+	abi_ret_default

linux-7.2.3/arch/xtensa/lib/udivsi3.S

@@ -0,0 +1,69 @@
+/* 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(__udivsi3)
+
+	abi_entry_default
+#if XCHAL_HAVE_DIV32
+	quou	a2, a2, a3
+#else
+	bltui	a3, 2, .Lle_one	/* check if the divisor <= 1 */
+
+	mov	a6, a2		/* keep dividend in a6 */
+	do_nsau	a5, a6, a2, a7	/* dividend_shift = nsau (dividend) */
+	do_nsau	a4, a3, a2, a7	/* divisor_shift = nsau (divisor) */
+	bgeu	a5, a4, .Lspecial
+
+	sub	a4, a4, a5	/* count = divisor_shift - dividend_shift */
+	ssl	a4
+	sll	a3, a3		/* divisor <<= count */
+	movi	a2, 0		/* quotient = 0 */
+
+	/* test-subtract-and-shift loop; one quotient bit on each iteration */
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lloopend
+#endif /* XCHAL_HAVE_LOOPS */
+.Lloop:
+	bltu	a6, a3, .Lzerobit
+	sub	a6, a6, a3
+	addi	a2, a2, 1
+.Lzerobit:
+	slli	a2, a2, 1
+	srli	a3, a3, 1
+#if !XCHAL_HAVE_LOOPS
+	addi	a4, a4, -1
+	bnez	a4, .Lloop
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lloopend:
+
+	bltu	a6, a3, .Lreturn
+	addi	a2, a2, 1	/* increment quotient if dividend >= divisor */
+.Lreturn:
+	abi_ret_default
+
+.Lle_one:
+	beqz	a3, .Lerror	/* if divisor == 1, return the dividend */
+	abi_ret_default
+
+.Lspecial:
+	/* return dividend >= divisor */
+	bltu	a6, a3, .Lreturn0
+	movi	a2, 1
+	abi_ret_default
+
+.Lerror:
+	/* Divide by zero: Use an illegal instruction to force an exception.
+	   The subsequent "DIV0" string can be recognized by the exception
+	   handler to identify the real cause of the exception.  */
+	ill
+	.ascii	"DIV0"
+
+.Lreturn0:
+	movi	a2, 0
+#endif /* XCHAL_HAVE_DIV32 */
+	abi_ret_default
+
+ENDPROC(__udivsi3)
+EXPORT_SYMBOL(__udivsi3)

linux-7.2.3/arch/xtensa/lib/umodsi3.S

@@ -0,0 +1,58 @@
+/* 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(__umodsi3)
+
+	abi_entry_default
+#if XCHAL_HAVE_DIV32
+	remu	a2, a2, a3
+#else
+	bltui	a3, 2, .Lle_one	/* check if the divisor is <= 1 */
+
+	do_nsau	a5, a2, a6, a7	/* dividend_shift = nsau (dividend) */
+	do_nsau	a4, a3, a6, a7	/* divisor_shift = nsau (divisor) */
+	bgeu	a5, a4, .Lspecial
+
+	sub	a4, a4, a5	/* count = divisor_shift - dividend_shift */
+	ssl	a4
+	sll	a3, a3		/* divisor <<= count */
+
+	/* test-subtract-and-shift loop */
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lloopend
+#endif /* XCHAL_HAVE_LOOPS */
+.Lloop:
+	bltu	a2, a3, .Lzerobit
+	sub	a2, a2, a3
+.Lzerobit:
+	srli	a3, a3, 1
+#if !XCHAL_HAVE_LOOPS
+	addi	a4, a4, -1
+	bnez	a4, .Lloop
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lloopend:
+
+.Lspecial:
+	bltu	a2, a3, .Lreturn
+	sub	a2, a2, a3	/* subtract once more if dividend >= divisor */
+.Lreturn:
+	abi_ret_default
+
+.Lle_one:
+	bnez	a3, .Lreturn0
+
+	/* Divide by zero: Use an illegal instruction to force an exception.
+	   The subsequent "DIV0" string can be recognized by the exception
+	   handler to identify the real cause of the exception.  */
+	ill
+	.ascii	"DIV0"
+
+.Lreturn0:
+	movi	a2, 0
+#endif /* XCHAL_HAVE_DIV32 */
+	abi_ret_default
+
+ENDPROC(__umodsi3)
+EXPORT_SYMBOL(__umodsi3)

linux-7.2.3/arch/xtensa/lib/umulsidi3.S

@@ -0,0 +1,233 @@
+/* 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>
+
+#if XCHAL_HAVE_MUL16 || XCHAL_HAVE_MUL32 || XCHAL_HAVE_MAC16
+#define XCHAL_NO_MUL 0
+#else
+#define XCHAL_NO_MUL 1
+#endif
+
+ENTRY(__umulsidi3)
+
+#ifdef __XTENSA_CALL0_ABI__
+	abi_entry(32)
+	s32i	a12, sp, 16
+	s32i	a13, sp, 20
+	s32i	a14, sp, 24
+	s32i	a15, sp, 28
+#elif XCHAL_NO_MUL
+	/* This is not really a leaf function; allocate enough stack space
+	   to allow CALL12s to a helper function.  */
+	abi_entry(32)
+#else
+	abi_entry_default
+#endif
+
+#ifdef __XTENSA_EB__
+#define wh a2
+#define wl a3
+#else
+#define wh a3
+#define wl a2
+#endif /* __XTENSA_EB__ */
+
+	/* This code is taken from the mulsf3 routine in ieee754-sf.S.
+	   See more comments there.  */
+
+#if XCHAL_HAVE_MUL32_HIGH
+	mull	a6, a2, a3
+	muluh	wh, a2, a3
+	mov	wl, a6
+
+#else /* ! MUL32_HIGH */
+
+#if defined(__XTENSA_CALL0_ABI__) && XCHAL_NO_MUL
+	/* a0 and a8 will be clobbered by calling the multiply function
+	   but a8 is not used here and need not be saved.  */
+	s32i	a0, sp, 0
+#endif
+
+#if XCHAL_HAVE_MUL16 || XCHAL_HAVE_MUL32
+
+#define a2h a4
+#define a3h a5
+
+	/* Get the high halves of the inputs into registers.  */
+	srli	a2h, a2, 16
+	srli	a3h, a3, 16
+
+#define a2l a2
+#define a3l a3
+
+#if XCHAL_HAVE_MUL32 && !XCHAL_HAVE_MUL16
+	/* Clear the high halves of the inputs.  This does not matter
+	   for MUL16 because the high bits are ignored.  */
+	extui	a2, a2, 0, 16
+	extui	a3, a3, 0, 16
+#endif
+#endif /* MUL16 || MUL32 */
+
+
+#if XCHAL_HAVE_MUL16
+
+#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
+	mul16u	dst, xreg ## xhalf, yreg ## yhalf
+
+#elif XCHAL_HAVE_MUL32
+
+#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
+	mull	dst, xreg ## xhalf, yreg ## yhalf
+
+#elif XCHAL_HAVE_MAC16
+
+/* The preprocessor insists on inserting a space when concatenating after
+   a period in the definition of do_mul below.  These macros are a workaround
+   using underscores instead of periods when doing the concatenation.  */
+#define umul_aa_ll umul.aa.ll
+#define umul_aa_lh umul.aa.lh
+#define umul_aa_hl umul.aa.hl
+#define umul_aa_hh umul.aa.hh
+
+#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
+	umul_aa_ ## xhalf ## yhalf	xreg, yreg; \
+	rsr	dst, ACCLO
+
+#else /* no multiply hardware */
+
+#define set_arg_l(dst, src) \
+	extui	dst, src, 0, 16
+#define set_arg_h(dst, src) \
+	srli	dst, src, 16
+
+#ifdef __XTENSA_CALL0_ABI__
+#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
+	set_arg_ ## xhalf (a13, xreg); \
+	set_arg_ ## yhalf (a14, yreg); \
+	call0	.Lmul_mulsi3; \
+	mov	dst, a12
+#else
+#define do_mul(dst, xreg, xhalf, yreg, yhalf) \
+	set_arg_ ## xhalf (a14, xreg); \
+	set_arg_ ## yhalf (a15, yreg); \
+	call12	.Lmul_mulsi3; \
+	mov	dst, a14
+#endif /* __XTENSA_CALL0_ABI__ */
+
+#endif /* no multiply hardware */
+
+	/* Add pp1 and pp2 into a6 with carry-out in a9.  */
+	do_mul(a6, a2, l, a3, h)	/* pp 1 */
+	do_mul(a11, a2, h, a3, l)	/* pp 2 */
+	movi	a9, 0
+	add	a6, a6, a11
+	bgeu	a6, a11, 1f
+	addi	a9, a9, 1
+1:
+	/* Shift the high half of a9/a6 into position in a9.  Note that
+	   this value can be safely incremented without any carry-outs.  */
+	ssai	16
+	src	a9, a9, a6
+
+	/* Compute the low word into a6.  */
+	do_mul(a11, a2, l, a3, l)	/* pp 0 */
+	sll	a6, a6
+	add	a6, a6, a11
+	bgeu	a6, a11, 1f
+	addi	a9, a9, 1
+1:
+	/* Compute the high word into wh.  */
+	do_mul(wh, a2, h, a3, h)	/* pp 3 */
+	add	wh, wh, a9
+	mov	wl, a6
+
+#endif /* !MUL32_HIGH */
+
+#if defined(__XTENSA_CALL0_ABI__) && XCHAL_NO_MUL
+	/* Restore the original return address.  */
+	l32i	a0, sp, 0
+#endif
+#ifdef __XTENSA_CALL0_ABI__
+	l32i	a12, sp, 16
+	l32i	a13, sp, 20
+	l32i	a14, sp, 24
+	l32i	a15, sp, 28
+	abi_ret(32)
+#else
+	abi_ret_default
+#endif
+
+#if XCHAL_NO_MUL
+
+	.macro	do_addx2 dst, as, at, tmp
+#if XCHAL_HAVE_ADDX
+	addx2	\dst, \as, \at
+#else
+	slli	\tmp, \as, 1
+	add	\dst, \tmp, \at
+#endif
+	.endm
+
+	.macro	do_addx4 dst, as, at, tmp
+#if XCHAL_HAVE_ADDX
+	addx4	\dst, \as, \at
+#else
+	slli	\tmp, \as, 2
+	add	\dst, \tmp, \at
+#endif
+	.endm
+
+	.macro	do_addx8 dst, as, at, tmp
+#if XCHAL_HAVE_ADDX
+	addx8	\dst, \as, \at
+#else
+	slli	\tmp, \as, 3
+	add	\dst, \tmp, \at
+#endif
+	.endm
+
+	/* For Xtensa processors with no multiply hardware, this simplified
+	   version of _mulsi3 is used for multiplying 16-bit chunks of
+	   the floating-point mantissas.  When using CALL0, this function
+	   uses a custom ABI: the inputs are passed in a13 and a14, the
+	   result is returned in a12, and a8 and a15 are clobbered.  */
+	.align	4
+.Lmul_mulsi3:
+	abi_entry_default
+
+	.macro mul_mulsi3_body dst, src1, src2, tmp1, tmp2
+	movi	\dst, 0
+1:	add	\tmp1, \src2, \dst
+	extui	\tmp2, \src1, 0, 1
+	movnez	\dst, \tmp1, \tmp2
+
+	do_addx2 \tmp1, \src2, \dst, \tmp1
+	extui	\tmp2, \src1, 1, 1
+	movnez	\dst, \tmp1, \tmp2
+
+	do_addx4 \tmp1, \src2, \dst, \tmp1
+	extui	\tmp2, \src1, 2, 1
+	movnez	\dst, \tmp1, \tmp2
+
+	do_addx8 \tmp1, \src2, \dst, \tmp1
+	extui	\tmp2, \src1, 3, 1
+	movnez	\dst, \tmp1, \tmp2
+
+	srli	\src1, \src1, 4
+	slli	\src2, \src2, 4
+	bnez	\src1, 1b
+	.endm
+
+#ifdef __XTENSA_CALL0_ABI__
+	mul_mulsi3_body a12, a13, a14, a15, a8
+#else
+	/* The result will be written into a2, so save that argument in a4.  */
+	mov	a4, a2
+	mul_mulsi3_body a2, a4, a3, a5, a6
+#endif
+	abi_ret_default
+#endif /* XCHAL_NO_MUL */
+
+ENDPROC(__umulsidi3)
+EXPORT_SYMBOL(__umulsidi3)

linux-7.2.3/arch/xtensa/lib/usercopy.S

@@ -0,0 +1,301 @@
+/*
+ *  arch/xtensa/lib/usercopy.S
+ *
+ *  Copy to/from user space (derived from arch/xtensa/lib/hal/memcopy.S)
+ *
+ *  DO NOT COMBINE this function with <arch/xtensa/lib/hal/memcopy.S>.
+ *  It needs to remain separate and distinct.  The hal files are part
+ *  of the Xtensa link-time HAL, and those files may differ per
+ *  processor configuration.  Patching the kernel for another
+ *  processor configuration includes replacing the hal files, and we
+ *  could lose the special functionality for accessing user-space
+ *  memory during such a patch.  We sacrifice a little code space here
+ *  in favor to simplify code maintenance.
+ *
+ *  This file is subject to the terms and conditions of the GNU General
+ *  Public License.  See the file "COPYING" in the main directory of
+ *  this archive for more details.
+ *
+ *  Copyright (C) 2002 Tensilica Inc.
+ */
+
+
+/*
+ * size_t __xtensa_copy_user (void *dst, const void *src, size_t len);
+ *
+ * The returned value is the number of bytes not copied.  Implies zero
+ * is success.
+ *
+ * The general case algorithm is as follows:
+ *   If the destination and source are both aligned,
+ *     do 16B chunks with a loop, and then finish up with
+ *     8B, 4B, 2B, and 1B copies conditional on the length.
+ *   If destination is aligned and source unaligned,
+ *     do the same, but use SRC to align the source data.
+ *   If destination is unaligned, align it by conditionally
+ *     copying 1B and 2B and then retest.
+ *   This code tries to use fall-through braches for the common
+ *     case of aligned destinations (except for the branches to
+ *     the alignment label).
+ *
+ * Register use:
+ *	a0/ return address
+ *	a1/ stack pointer
+ *	a2/ return value
+ *	a3/ src
+ *	a4/ length
+ *	a5/ dst
+ *	a6/ tmp
+ *	a7/ tmp
+ *	a8/ tmp
+ *	a9/ tmp
+ *	a10/ tmp
+ *	a11/ original length
+ */
+
+#include <linux/linkage.h>
+#include <asm/asmmacro.h>
+#include <asm/core.h>
+
+	.text
+ENTRY(__xtensa_copy_user)
+
+#if !XCHAL_HAVE_LOOPS && defined(__XTENSA_CALL0_ABI__)
+#define STACK_SIZE 4
+#else
+#define STACK_SIZE 0
+#endif
+	abi_entry(STACK_SIZE)
+	# a2/ dst, a3/ src, a4/ len
+	mov	a5, a2		# copy dst so that a2 is return value
+	mov	a11, a4		# preserve original len for error case
+.Lcommon:
+	bbsi.l	a2, 0, .Ldst1mod2 # if dst is 1 mod 2
+	bbsi.l	a2, 1, .Ldst2mod4 # if dst is 2 mod 4
+.Ldstaligned:	# return here from .Ldstunaligned when dst is aligned
+	srli	a7, a4, 4	# number of loop iterations with 16B
+				# per iteration
+	movi	a8, 3		  # if source is also aligned,
+	bnone	a3, a8, .Laligned # then use word copy
+	__ssa8	a3		# set shift amount from byte offset
+	bnez	a4, .Lsrcunaligned
+	movi	a2, 0		# return success for len==0
+	abi_ret(STACK_SIZE)
+
+/*
+ * Destination is unaligned
+ */
+
+.Ldst1mod2:	# dst is only byte aligned
+	bltui	a4, 7, .Lbytecopy	# do short copies byte by byte
+
+	# copy 1 byte
+EX(10f)	l8ui	a6, a3, 0
+	addi	a3, a3,  1
+EX(10f)	s8i	a6, a5,  0
+	addi	a5, a5,  1
+	addi	a4, a4, -1
+	bbci.l	a5, 1, .Ldstaligned	# if dst is now aligned, then
+					# return to main algorithm
+.Ldst2mod4:	# dst 16-bit aligned
+	# copy 2 bytes
+	bltui	a4, 6, .Lbytecopy	# do short copies byte by byte
+EX(10f)	l8ui	a6, a3, 0
+EX(10f)	l8ui	a7, a3, 1
+	addi	a3, a3,  2
+EX(10f)	s8i	a6, a5,  0
+EX(10f)	s8i	a7, a5,  1
+	addi	a5, a5,  2
+	addi	a4, a4, -2
+	j	.Ldstaligned	# dst is now aligned, return to main algorithm
+
+/*
+ * Byte by byte copy
+ */
+	.align	4
+	.byte	0		# 1 mod 4 alignment for LOOPNEZ
+				# (0 mod 4 alignment for LBEG)
+.Lbytecopy:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a4, .Lbytecopydone
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a4, .Lbytecopydone
+	add	a7, a3, a4	# a7 = end address for source
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lnextbyte:
+EX(10f)	l8ui	a6, a3, 0
+	addi	a3, a3, 1
+EX(10f)	s8i	a6, a5, 0
+	addi	a5, a5, 1
+#if !XCHAL_HAVE_LOOPS
+	blt	a3, a7, .Lnextbyte
+#endif /* !XCHAL_HAVE_LOOPS */
+.Lbytecopydone:
+	movi	a2, 0		# return success for len bytes copied
+	abi_ret(STACK_SIZE)
+
+/*
+ * Destination and source are word-aligned.
+ */
+	# copy 16 bytes per iteration for word-aligned dst and word-aligned src
+	.align	4		# 1 mod 4 alignment for LOOPNEZ
+	.byte	0		# (0 mod 4 alignment for LBEG)
+.Laligned:
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .Loop1done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .Loop1done
+	slli	a8, a7, 4
+	add	a8, a8, a3	# a8 = end of last 16B source chunk
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop1:
+EX(10f)	l32i	a6, a3,  0
+EX(10f)	l32i	a7, a3,  4
+EX(10f)	s32i	a6, a5,  0
+EX(10f)	l32i	a6, a3,  8
+EX(10f)	s32i	a7, a5,  4
+EX(10f)	l32i	a7, a3, 12
+EX(10f)	s32i	a6, a5,  8
+	addi	a3, a3, 16
+EX(10f)	s32i	a7, a5, 12
+	addi	a5, a5, 16
+#if !XCHAL_HAVE_LOOPS
+	blt	a3, a8, .Loop1
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop1done:
+	bbci.l	a4, 3, .L2
+	# copy 8 bytes
+EX(10f)	l32i	a6, a3,  0
+EX(10f)	l32i	a7, a3,  4
+	addi	a3, a3,  8
+EX(10f)	s32i	a6, a5,  0
+EX(10f)	s32i	a7, a5,  4
+	addi	a5, a5,  8
+.L2:
+	bbci.l	a4, 2, .L3
+	# copy 4 bytes
+EX(10f)	l32i	a6, a3,  0
+	addi	a3, a3,  4
+EX(10f)	s32i	a6, a5,  0
+	addi	a5, a5,  4
+.L3:
+	bbci.l	a4, 1, .L4
+	# copy 2 bytes
+EX(10f)	l16ui	a6, a3,  0
+	addi	a3, a3,  2
+EX(10f)	s16i	a6, a5,  0
+	addi	a5, a5,  2
+.L4:
+	bbci.l	a4, 0, .L5
+	# copy 1 byte
+EX(10f)	l8ui	a6, a3,  0
+EX(10f)	s8i	a6, a5,  0
+.L5:
+	movi	a2, 0		# return success for len bytes copied
+	abi_ret(STACK_SIZE)
+
+/*
+ * Destination is aligned, Source is unaligned
+ */
+
+	.align	4
+	.byte	0		# 1 mod 4 alignement for LOOPNEZ
+				# (0 mod 4 alignment for LBEG)
+.Lsrcunaligned:
+	# copy 16 bytes per iteration for word-aligned dst and unaligned src
+	and	a10, a3, a8	# save unalignment offset for below
+	sub	a3, a3, a10	# align a3 (to avoid sim warnings only; not needed for hardware)
+EX(10f)	l32i	a6, a3, 0	# load first word
+#if XCHAL_HAVE_LOOPS
+	loopnez	a7, .Loop2done
+#else /* !XCHAL_HAVE_LOOPS */
+	beqz	a7, .Loop2done
+#if defined(__XTENSA_CALL0_ABI__)
+	s32i	a10, a1, 0
+	slli	a10, a7, 4
+	add	a10, a10, a3	# a10 = end of last 16B source chunk
+#else
+	slli	a12, a7, 4
+	add	a12, a12, a3	# a12 = end of last 16B source chunk
+#endif
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop2:
+EX(10f)	l32i	a7, a3,  4
+EX(10f)	l32i	a8, a3,  8
+	__src_b	a6, a6, a7
+EX(10f)	s32i	a6, a5,  0
+EX(10f)	l32i	a9, a3, 12
+	__src_b	a7, a7, a8
+EX(10f)	s32i	a7, a5,  4
+EX(10f)	l32i	a6, a3, 16
+	__src_b	a8, a8, a9
+EX(10f)	s32i	a8, a5,  8
+	addi	a3, a3, 16
+	__src_b	a9, a9, a6
+EX(10f)	s32i	a9, a5, 12
+	addi	a5, a5, 16
+#if !XCHAL_HAVE_LOOPS
+#if defined(__XTENSA_CALL0_ABI__)
+	blt	a3, a10, .Loop2
+	l32i	a10, a1, 0
+#else
+	blt	a3, a12, .Loop2
+#endif
+#endif /* !XCHAL_HAVE_LOOPS */
+.Loop2done:
+	bbci.l	a4, 3, .L12
+	# copy 8 bytes
+EX(10f)	l32i	a7, a3,  4
+EX(10f)	l32i	a8, a3,  8
+	__src_b	a6, a6, a7
+EX(10f)	s32i	a6, a5,  0
+	addi	a3, a3,  8
+	__src_b	a7, a7, a8
+EX(10f)	s32i	a7, a5,  4
+	addi	a5, a5,  8
+	mov	a6, a8
+.L12:
+	bbci.l	a4, 2, .L13
+	# copy 4 bytes
+EX(10f)	l32i	a7, a3,  4
+	addi	a3, a3,  4
+	__src_b	a6, a6, a7
+EX(10f)	s32i	a6, a5,  0
+	addi	a5, a5,  4
+	mov	a6, a7
+.L13:
+	add	a3, a3, a10	# readjust a3 with correct misalignment
+	bbci.l	a4, 1, .L14
+	# copy 2 bytes
+EX(10f)	l8ui	a6, a3,  0
+EX(10f)	l8ui	a7, a3,  1
+	addi	a3, a3,  2
+EX(10f)	s8i	a6, a5,  0
+EX(10f)	s8i	a7, a5,  1
+	addi	a5, a5,  2
+.L14:
+	bbci.l	a4, 0, .L15
+	# copy 1 byte
+EX(10f)	l8ui	a6, a3,  0
+EX(10f)	s8i	a6, a5,  0
+.L15:
+	movi	a2, 0		# return success for len bytes copied
+	abi_ret(STACK_SIZE)
+
+ENDPROC(__xtensa_copy_user)
+EXPORT_SYMBOL(__xtensa_copy_user)
+
+	.section .fixup, "ax"
+	.align	4
+
+/* a2 = original dst; a5 = current dst; a11= original len
+ * bytes_copied = a5 - a2
+ * retval = bytes_not_copied = original len - bytes_copied
+ * retval = a11 - (a5 - a2)
+ */
+
+
+10:
+	sub	a2, a5, a2	/* a2 <-- bytes copied */
+	sub	a2, a11, a2	/* a2 <-- bytes not copied */
+	abi_ret(STACK_SIZE)