提交 249ac17e 编写于 作者: C Chris Zankel 提交者: Linus Torvalds

[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 4

The attached patches provides part 4 of an architecture implementation for the
Tensilica Xtensa CPU series.
Signed-off-by: NChris Zankel <chris@zankel.net>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
上级 5a0015d6
#
# Makefile for Xtensa-specific library files.
#
lib-y += memcopy.o memset.o checksum.o strcasecmp.o \
usercopy.o strncpy_user.o strnlen_user.o
lib-$(CONFIG_PCI) += pci-auto.o
/*
* 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
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <asm/errno.h>
#include <linux/linkage.h>
#define _ASMLANGUAGE
#include <xtensa/config/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.
*/
entry sp, 32
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
retw
/* 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 */
/*
* Copy from ds while checksumming, otherwise like csum_partial
*
* The macros SRC and DST specify the type of access for the instruction.
* thus we can call a custom exception handler for each access type.
*/
#define SRC(y...) \
9999: y; \
.section __ex_table, "a"; \
.long 9999b, 6001f ; \
.previous
#define DST(y...) \
9999: y; \
.section __ex_table, "a"; \
.long 9999b, 6002f ; \
.previous
/*
unsigned int csum_partial_copy_generic (const char *src, char *dst, int len,
int sum, int *src_err_ptr, int *dst_err_ptr)
a2 = src
a3 = dst
a4 = len
a5 = sum
a6 = src_err_ptr
a7 = dst_err_ptr
a8 = temp
a9 = temp
a10 = temp
a11 = original len for exception handling
a12 = original dst for exception handling
This function is optimized for 4-byte aligned addresses. Other
alignments work, but not nearly as efficiently.
*/
ENTRY(csum_partial_copy_generic)
entry sp, 32
mov a12, a3
mov a11, a4
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
SRC( l32i a9, a2, 0 )
SRC( l32i a8, a2, 4 )
DST( s32i a9, a3, 0 )
DST( s32i a8, a3, 4 )
ONES_ADD(a5, a9)
ONES_ADD(a5, a8)
SRC( l32i a9, a2, 8 )
SRC( l32i a8, a2, 12 )
DST( s32i a9, a3, 8 )
DST( s32i a8, a3, 12 )
ONES_ADD(a5, a9)
ONES_ADD(a5, a8)
SRC( l32i a9, a2, 16 )
SRC( l32i a8, a2, 20 )
DST( s32i a9, a3, 16 )
DST( s32i a8, a3, 20 )
ONES_ADD(a5, a9)
ONES_ADD(a5, a8)
SRC( l32i a9, a2, 24 )
SRC( l32i a8, a2, 28 )
DST( s32i a9, a3, 24 )
DST( 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
SRC( l32i a9, a2, 0 )
DST( 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
SRC( l16ui a9, a2, 0 )
DST( 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 */
SRC( l8ui a9, a2, 0 )
DST( 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
retw
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
SRC( l8ui a9, a2, 0 )
SRC( l8ui a8, a2, 1 )
DST( s8i a9, a3, 0 )
DST( 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 */
# Exception handler:
.section .fixup, "ax"
/*
a6 = src_err_ptr
a7 = dst_err_ptr
a11 = original len for exception handling
a12 = original dst for exception handling
*/
6001:
_movi a2, -EFAULT
s32i a2, a6, 0 /* src_err_ptr */
# clear the complete destination - computing the rest
# is too much work
movi a2, 0
#if XCHAL_HAVE_LOOPS
loopgtz a11, 2f
#else
beqz a11, 2f
add a11, a11, a12 /* a11 = ending address */
.Leloop:
#endif
s8i a2, a12, 0
addi a12, a12, 1
#if !XCHAL_HAVE_LOOPS
blt a12, a11, .Leloop
#endif
2:
retw
6002:
movi a2, -EFAULT
s32i a2, a7, 0 /* dst_err_ptr */
movi a2, 0
retw
.previous
/*
* 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 - 2005 Tensilica Inc.
*/
#include <xtensa/coreasm.h>
.macro src_b r, w0, w1
#ifdef __XTENSA_EB__
src \r, \w0, \w1
#else
src \r, \w1, \w0
#endif
.endm
.macro ssa8 r
#ifdef __XTENSA_EB__
ssa8b \r
#else
ssa8l \r
#endif
.endm
/*
* void *memcpy(void *dst, const void *src, size_t len);
* void *memmove(void *dst, const void *src, size_t len);
* void *bcopy(const void *src, void *dst, size_t len);
*
* This function is intended to do the same thing as the standard
* library function memcpy() (or bcopy()) 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 bcopy version is provided here to avoid the overhead
* of an extra call, for callers that require this convention.
*
* 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
.align 4
.global bcopy
.type bcopy,@function
bcopy:
entry sp, 16 # minimal stack frame
# a2=src, a3=dst, a4=len
mov a5, a3 # copy dst so that a2 is return value
mov a3, a2
mov a2, a5
j .Lcommon # go to common code for memcpy+bcopy
/*
* 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
blt a3, a7, .Lnextbyte
#endif /* !XCHAL_HAVE_LOOPS */
.Lbytecopydone:
retw
/*
* 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
.align 4
.global memcpy
.type memcpy,@function
memcpy:
.global memmove
.type memmove,@function
memmove:
entry sp, 16 # minimal stack frame
# 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
blt a3, a8, .Loop1
#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
retw
.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
retw
.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
retw
.L5:
# copy 1 byte
l8ui a6, a3, 0
s8i a6, a5, 0
retw
/*
* 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
#define SIM_CHECKS_ALIGNMENT 1 /* set to 1 when running on ISS (simulator) 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, .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
blt a3, a10, .Loop2
#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: retw
.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
retw
.L15:
# copy 1 byte
l8ui a6, a3, 0
s8i a6, a5, 0
retw
/*
* Local Variables:
* mode:fundamental
* comment-start: "# "
* comment-start-skip: "# *"
* End:
*/
/*
* 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 <xtensa/coreasm.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).
*/
/* Load or store instructions that may cause exceptions use the EX macro. */
#define EX(insn,reg1,reg2,offset,handler) \
9: insn reg1, reg2, offset; \
.section __ex_table, "a"; \
.word 9b, handler; \
.previous
.text
.align 4
.global memset
.type memset,@function
memset:
entry sp, 16 # minimal stack frame
# 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
retw
/*
* 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(s32i, a3, a5, 0, memset_fixup)
EX(s32i, a3, a5, 4, memset_fixup)
EX(s32i, a3, a5, 8, memset_fixup)
EX(s32i, a3, a5, 12, memset_fixup)
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(s32i, a3, a5, 0, memset_fixup)
EX(s32i, a3, a5, 4, memset_fixup)
addi a5, a5, 8
.L2:
bbci.l a4, 2, .L3
# set 4 bytes
EX(s32i, a3, a5, 0, memset_fixup)
addi a5, a5, 4
.L3:
bbci.l a4, 1, .L4
# set 2 bytes
EX(s16i, a3, a5, 0, memset_fixup)
addi a5, a5, 2
.L4:
bbci.l a4, 0, .L5
# set 1 byte
EX(s8i, a3, a5, 0, memset_fixup)
.L5:
.Lret1:
retw
/*
* 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(s8i, a3, a5, 0, memset_fixup)
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(s16i, a3, a5, 0, memset_fixup)
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(s8i, a3, a5, 0, memset_fixup)
addi a5, a5, 1
#if !XCHAL_HAVE_LOOPS
blt a5, a6, .Lbyteloop
#endif /* !XCHAL_HAVE_LOOPS */
.Lbytesetdone:
retw
.section .fixup, "ax"
.align 4
/* We return zero if a failure occurred. */
memset_fixup:
movi a2, 0
retw
/*
* arch/xtensa/kernel/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>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#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)
*
*/
/* define DEBUG to print some debugging messages. */
#undef DEBUG
#ifdef DEBUG
# define DBG(x...) printk(x)
#else
# define DBG(x...)
#endif
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;
DBG("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;
DBG("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);
DBG("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;
DBG("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, found_multi=0;
unsigned short vid;
unsigned char header_type;
struct pci_dev *dev = &pciauto_dev;
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 = header_type & 0x80;
pci_read_config_word(dev, PCI_VENDOR_ID, &vid);
if (vid == 0xffff || vid == 0x0000) {
found_multi = 0;
continue;
}
pci_read_config_dword(dev, PCI_CLASS_REVISION, &pci_class);
if ((pci_class >> 16) == PCI_CLASS_BRIDGE_PCI) {
int iosave, memsave;
DBG("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;
}
#if 0
/* Skip legacy mode IDE controller */
if ((pci_class >> 16) == PCI_CLASS_STORAGE_IDE) {
unsigned char prg_iface;
pci_read_config_byte(dev, PCI_CLASS_PROG, &prg_iface);
if (!(prg_iface & PCIAUTO_IDE_MODE_MASK)) {
DBG("PCI Autoconfig: Skipping legacy mode "
"IDE controller\n");
continue;
}
}
#endif
/*
* 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 */
DBG("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/arch/xtensa/lib/strcasecmp.c
*
* 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/string.h>
/* We handle nothing here except the C locale. Since this is used in
only one place, on strings known to contain only 7 bit ASCII, this
is ok. */
int strcasecmp(const char *a, const char *b)
{
int ca, cb;
do {
ca = *a++ & 0xff;
cb = *b++ & 0xff;
if (ca >= 'A' && ca <= 'Z')
ca += 'a' - 'A';
if (cb >= 'A' && cb <= 'Z')
cb += 'a' - 'A';
} while (ca == cb && ca != '\0');
return ca - cb;
}
/*
* 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 <xtensa/coreasm.h>
#include <linux/errno.h>
/* Load or store instructions that may cause exceptions use the EX macro. */
#define EX(insn,reg1,reg2,offset,handler) \
9: insn reg1, reg2, offset; \
.section __ex_table, "a"; \
.word 9b, handler; \
.previous
/*
* char *__strncpy_user(char *dst, const char *src, size_t len)
*/
.text
.begin literal
.align 4
.Lmask0:
.byte 0xff, 0x00, 0x00, 0x00
.Lmask1:
.byte 0x00, 0xff, 0x00, 0x00
.Lmask2:
.byte 0x00, 0x00, 0xff, 0x00
.Lmask3:
.byte 0x00, 0x00, 0x00, 0xff
.end literal
# 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
# a12/ tmp
.align 4
.global __strncpy_user
.type __strncpy_user,@function
__strncpy_user:
entry sp, 16 # minimal stack frame
# a2/ dst, a3/ src, a4/ len
mov a11, a2 # leave dst in return value register
beqz a4, .Lret # if len is zero
l32r a5, .Lmask0 # mask for byte 0
l32r a6, .Lmask1 # mask for byte 1
l32r a7, .Lmask2 # mask for byte 2
l32r a8, .Lmask3 # 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 a12, 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(l8ui, a9, a3, 0, fixup_l) # get byte 0
addi a3, a3, 1 # advance src pointer
EX(s8i, a9, a11, 0, fixup_s) # 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(l8ui, a9, a3, 0, fixup_l) # get byte 0
/* 1-cycle interlock */
EX(s8i, a9, a11, 0, fixup_s) # 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(l8ui, a9, a3, 1, fixup_l) # get byte 0
addi a3, a3, 2 # advance src pointer
EX(s8i, a9, a11, 0, fixup_s) # 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
retw
/*
* 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 a12, .Loop1done
#else
beqz a12, .Loop1done
slli a12, a12, 2
add a12, a12, a11 # a12 = end of last 4B chunck
#endif
.Loop1:
EX(l32i, a9, a3, 0, fixup_l) # 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(s32i, a9, a11, 0, fixup_s) # 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, a12, .Loop1
#endif
.Loop1done:
bbci.l a4, 1, .L100
# copy 2 bytes
EX(l16ui, a9, a3, 0, fixup_l)
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(s16i, a9, a11, 0, fixup_s)
addi a11, a11, 2 # advance dst pointer
.L100:
bbci.l a4, 0, .Lret
EX(l8ui, a9, a3, 0, fixup_l)
/* slot */
EX(s8i, a9, a11, 0, fixup_s)
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
retw
.Lz0: # byte 0 is zero
#ifdef __XTENSA_EB__
movi a9, 0
#endif /* __XTENSA_EB__ */
EX(s8i, a9, a11, 0, fixup_s)
sub a2, a11, a2 # compute strlen
retw
.Lz1: # byte 1 is zero
#ifdef __XTENSA_EB__
extui a9, a9, 16, 16
#endif /* __XTENSA_EB__ */
EX(s16i, a9, a11, 0, fixup_s)
addi a11, a11, 1 # advance dst pointer
sub a2, a11, a2 # compute strlen
retw
.Lz2: # byte 2 is zero
#ifdef __XTENSA_EB__
extui a9, a9, 16, 16
#endif /* __XTENSA_EB__ */
EX(s16i, a9, a11, 0, fixup_s)
movi a9, 0
EX(s8i, a9, a11, 2, fixup_s)
addi a11, a11, 2 # advance dst pointer
sub a2, a11, a2 # compute strlen
retw
.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 a12, a11, a4 # a12 = ending address
#endif /* XCHAL_HAVE_LOOPS */
.Lnextbyte:
EX(l8ui, a9, a3, 0, fixup_l)
addi a3, a3, 1
EX(s8i, a9, a11, 0, fixup_s)
beqz a9, .Lunalignedend
addi a11, a11, 1
#if !XCHAL_HAVE_LOOPS
blt a11, a12, .Lnextbyte
#endif
.Lunalignedend:
sub a2, a11, a2 # compute strlen
retw
.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. */
fixup_s:
fixup_l:
movi a2, -EFAULT
retw
/*
* 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 <xtensa/coreasm.h>
/* Load or store instructions that may cause exceptions use the EX macro. */
#define EX(insn,reg1,reg2,offset,handler) \
9: insn reg1, reg2, offset; \
.section __ex_table, "a"; \
.word 9b, handler; \
.previous
/*
* size_t __strnlen_user(const char *s, size_t len)
*/
.text
.begin literal
.align 4
.Lmask0:
.byte 0xff, 0x00, 0x00, 0x00
.Lmask1:
.byte 0x00, 0xff, 0x00, 0x00
.Lmask2:
.byte 0x00, 0x00, 0xff, 0x00
.Lmask3:
.byte 0x00, 0x00, 0x00, 0xff
.end literal
# Register use:
# a2/ src
# a3/ len
# a4/ tmp
# a5/ mask0
# a6/ mask1
# a7/ mask2
# a8/ mask3
# a9/ tmp
# a10/ tmp
.align 4
.global __strnlen_user
.type __strnlen_user,@function
__strnlen_user:
entry sp, 16 # minimal stack frame
# a2/ s, a3/ len
addi a4, a2, -4 # because we overincrement at the end;
# we compensate with load offsets of 4
l32r a5, .Lmask0 # mask for byte 0
l32r a6, .Lmask1 # mask for byte 1
l32r a7, .Lmask2 # mask for byte 2
l32r a8, .Lmask3 # 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(l32i, a9, a4, 4, lenfixup) # 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(l32i, a9, a4, 4, lenfixup) # 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
retw
# 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
retw
.Lz1: # byte 1 is zero
addi a4, a4, 1+1 # point just beyond zero byte
sub a2, a4, a2 # subtract to get length
retw
.Lz2: # byte 2 is zero
addi a4, a4, 2+1 # point just beyond zero byte
sub a2, a4, a2 # subtract to get length
retw
.L1mod2: # address is odd
EX(l8ui, a9, a4, 4, lenfixup) # 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(l32i, a9, a4, 0, lenfixup) # 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
retw
.section .fixup, "ax"
.align 4
lenfixup:
movi a2, 0
retw
/*
* 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 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 loose 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 <xtensa/coreasm.h>
#ifdef __XTENSA_EB__
#define ALIGN(R, W0, W1) src R, W0, W1
#define SSA8(R) ssa8b R
#else
#define ALIGN(R, W0, W1) src R, W1, W0
#define SSA8(R) ssa8l R
#endif
/* Load or store instructions that may cause exceptions use the EX macro. */
#define EX(insn,reg1,reg2,offset,handler) \
9: insn reg1, reg2, offset; \
.section __ex_table, "a"; \
.word 9b, handler; \
.previous
.text
.align 4
.global __xtensa_copy_user
.type __xtensa_copy_user,@function
__xtensa_copy_user:
entry sp, 16 # minimal stack frame
# 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
retw
/*
* Destination is unaligned
*/
.Ldst1mod2: # dst is only byte aligned
bltui a4, 7, .Lbytecopy # do short copies byte by byte
# copy 1 byte
EX(l8ui, a6, a3, 0, l_fixup)
addi a3, a3, 1
EX(s8i, a6, a5, 0, s_fixup)
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(l8ui, a6, a3, 0, l_fixup)
EX(l8ui, a7, a3, 1, l_fixup)
addi a3, a3, 2
EX(s8i, a6, a5, 0, s_fixup)
EX(s8i, a7, a5, 1, s_fixup)
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(l8ui, a6, a3, 0, l_fixup)
addi a3, a3, 1
EX(s8i, a6, a5, 0, s_fixup)
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
retw
/*
* 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(l32i, a6, a3, 0, l_fixup)
EX(l32i, a7, a3, 4, l_fixup)
EX(s32i, a6, a5, 0, s_fixup)
EX(l32i, a6, a3, 8, l_fixup)
EX(s32i, a7, a5, 4, s_fixup)
EX(l32i, a7, a3, 12, l_fixup)
EX(s32i, a6, a5, 8, s_fixup)
addi a3, a3, 16
EX(s32i, a7, a5, 12, s_fixup)
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(l32i, a6, a3, 0, l_fixup)
EX(l32i, a7, a3, 4, l_fixup)
addi a3, a3, 8
EX(s32i, a6, a5, 0, s_fixup)
EX(s32i, a7, a5, 4, s_fixup)
addi a5, a5, 8
.L2:
bbci.l a4, 2, .L3
# copy 4 bytes
EX(l32i, a6, a3, 0, l_fixup)
addi a3, a3, 4
EX(s32i, a6, a5, 0, s_fixup)
addi a5, a5, 4
.L3:
bbci.l a4, 1, .L4
# copy 2 bytes
EX(l16ui, a6, a3, 0, l_fixup)
addi a3, a3, 2
EX(s16i, a6, a5, 0, s_fixup)
addi a5, a5, 2
.L4:
bbci.l a4, 0, .L5
# copy 1 byte
EX(l8ui, a6, a3, 0, l_fixup)
EX(s8i, a6, a5, 0, s_fixup)
.L5:
movi a2, 0 # return success for len bytes copied
retw
/*
* 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(l32i, a6, a3, 0, l_fixup) # 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:
EX(l32i, a7, a3, 4, l_fixup)
EX(l32i, a8, a3, 8, l_fixup)
ALIGN( a6, a6, a7)
EX(s32i, a6, a5, 0, s_fixup)
EX(l32i, a9, a3, 12, l_fixup)
ALIGN( a7, a7, a8)
EX(s32i, a7, a5, 4, s_fixup)
EX(l32i, a6, a3, 16, l_fixup)
ALIGN( a8, a8, a9)
EX(s32i, a8, a5, 8, s_fixup)
addi a3, a3, 16
ALIGN( a9, a9, a6)
EX(s32i, a9, a5, 12, s_fixup)
addi a5, a5, 16
#if !XCHAL_HAVE_LOOPS
blt a3, a10, .Loop2
#endif /* !XCHAL_HAVE_LOOPS */
.Loop2done:
bbci.l a4, 3, .L12
# copy 8 bytes
EX(l32i, a7, a3, 4, l_fixup)
EX(l32i, a8, a3, 8, l_fixup)
ALIGN( a6, a6, a7)
EX(s32i, a6, a5, 0, s_fixup)
addi a3, a3, 8
ALIGN( a7, a7, a8)
EX(s32i, a7, a5, 4, s_fixup)
addi a5, a5, 8
mov a6, a8
.L12:
bbci.l a4, 2, .L13
# copy 4 bytes
EX(l32i, a7, a3, 4, l_fixup)
addi a3, a3, 4
ALIGN( a6, a6, a7)
EX(s32i, a6, a5, 0, s_fixup)
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(l8ui, a6, a3, 0, l_fixup)
EX(l8ui, a7, a3, 1, l_fixup)
addi a3, a3, 2
EX(s8i, a6, a5, 0, s_fixup)
EX(s8i, a7, a5, 1, s_fixup)
addi a5, a5, 2
.L14:
bbci.l a4, 0, .L15
# copy 1 byte
EX(l8ui, a6, a3, 0, l_fixup)
EX(s8i, a6, a5, 0, s_fixup)
.L15:
movi a2, 0 # return success for len bytes copied
retw
.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)
*
* Clearing the remaining pieces of kernel memory plugs security
* holes. This functionality is the equivalent of the *_zeroing
* functions that some architectures provide.
*/
.Lmemset:
.word memset
s_fixup:
sub a2, a5, a2 /* a2 <-- bytes copied */
sub a2, a11, a2 /* a2 <-- bytes not copied */
retw
l_fixup:
sub a2, a5, a2 /* a2 <-- bytes copied */
sub a2, a11, a2 /* a2 <-- bytes not copied == return value */
/* void *memset(void *s, int c, size_t n); */
mov a6, a5 /* s */
movi a7, 0 /* c */
mov a8, a2 /* n */
l32r a4, .Lmemset
callx4 a4
/* Ignore memset return value in a6. */
/* a2 still contains bytes not copied. */
retw
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