diff options
Diffstat (limited to 'kernel/arch/xtensa/lib')
| -rw-r--r-- | kernel/arch/xtensa/lib/Makefile | 7 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/checksum.S | 412 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/memcopy.S | 576 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/memset.S | 160 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/pci-auto.c | 347 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/strncpy_user.S | 225 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/strnlen_user.S | 147 | ||||
| -rw-r--r-- | kernel/arch/xtensa/lib/usercopy.S | 320 |
8 files changed, 2194 insertions, 0 deletions
diff --git a/kernel/arch/xtensa/lib/Makefile b/kernel/arch/xtensa/lib/Makefile new file mode 100644 index 000000000..6c4fdd86a --- /dev/null +++ b/kernel/arch/xtensa/lib/Makefile @@ -0,0 +1,7 @@ +# +# Makefile for Xtensa-specific library files. +# + +lib-y += memcopy.o memset.o checksum.o \ + usercopy.o strncpy_user.o strnlen_user.o +lib-$(CONFIG_PCI) += pci-auto.o diff --git a/kernel/arch/xtensa/lib/checksum.S b/kernel/arch/xtensa/lib/checksum.S new file mode 100644 index 000000000..4eb573d27 --- /dev/null +++ b/kernel/arch/xtensa/lib/checksum.S @@ -0,0 +1,412 @@ +/* + * 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> +#include <variant/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 */ + +ENDPROC(csum_partial) + +/* + * 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 */ + +ENDPROC(csum_partial_copy_generic) + + +# 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 diff --git a/kernel/arch/xtensa/lib/memcopy.S b/kernel/arch/xtensa/lib/memcopy.S new file mode 100644 index 000000000..b1c219aca --- /dev/null +++ b/kernel/arch/xtensa/lib/memcopy.S @@ -0,0 +1,576 @@ +/* + * 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 <variant/core.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); + * + * 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: + 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: + + 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 + 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 + 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 + +/* 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: 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 + + +/* + * void bcopy(const void *src, void *dest, size_t n); + */ + .align 4 + .global bcopy + .type bcopy,@function +bcopy: + entry sp, 16 # minimal stack frame + # a2=src, a3=dst, a4=len + mov a5, a3 + mov a3, a2 + mov a2, a5 + j .Lmovecommon # go to common code for memmove+bcopy + +/* + * 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: + retw + +/* + * 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 + + .align 4 + .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 +.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, .backLoop1done +#else /* !XCHAL_HAVE_LOOPS */ + beqz a7, .backLoop1done + slli a8, a7, 4 + sub a8, a3, a8 # a8 = start of first 16B source chunk +#endif /* !XCHAL_HAVE_LOOPS */ +.backLoop1: + 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, .backLoop1 # continue loop if a3:src != a8:src_start +#endif /* !XCHAL_HAVE_LOOPS */ +.backLoop1done: + 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 + retw +.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 + retw +.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 + retw +.Lback5: + # copy 1 byte + addi a3, a3, -1 + l8ui a6, a3, 0 + addi a5, a5, -1 + s8i a6, a5, 0 + retw + +/* + * 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, .backLoop2done +#else /* !XCHAL_HAVE_LOOPS */ + beqz a7, .backLoop2done + slli a10, a7, 4 + sub a10, a3, a10 # a10 = start of first 16B source chunk +#endif /* !XCHAL_HAVE_LOOPS */ +.backLoop2: + 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, .backLoop2 # continue loop if a3:src != a10:src_start +#endif /* !XCHAL_HAVE_LOOPS */ +.backLoop2done: + 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: + retw +.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 + retw +.Lback15: + # copy 1 byte + addi a3, a3, -1 + addi a5, a5, -1 + l8ui a6, a3, 0 + s8i a6, a5, 0 + retw + + +/* + * Local Variables: + * mode:fundamental + * comment-start: "# " + * comment-start-skip: "# *" + * End: + */ diff --git a/kernel/arch/xtensa/lib/memset.S b/kernel/arch/xtensa/lib/memset.S new file mode 100644 index 000000000..10b8c400f --- /dev/null +++ b/kernel/arch/xtensa/lib/memset.S @@ -0,0 +1,160 @@ +/* + * 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 <variant/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). + */ + +/* 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 diff --git a/kernel/arch/xtensa/lib/pci-auto.c b/kernel/arch/xtensa/lib/pci-auto.c new file mode 100644 index 000000000..34d05abbd --- /dev/null +++ b/kernel/arch/xtensa/lib/pci-auto.c @@ -0,0 +1,347 @@ +/* + * 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> + * + * 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; +} diff --git a/kernel/arch/xtensa/lib/strncpy_user.S b/kernel/arch/xtensa/lib/strncpy_user.S new file mode 100644 index 000000000..1ad0ecf45 --- /dev/null +++ b/kernel/arch/xtensa/lib/strncpy_user.S @@ -0,0 +1,225 @@ +/* + * 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 <variant/core.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) + */ + +#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 +# a12/ tmp + +.text +.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 + 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 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 + diff --git a/kernel/arch/xtensa/lib/strnlen_user.S b/kernel/arch/xtensa/lib/strnlen_user.S new file mode 100644 index 000000000..4c03b1e58 --- /dev/null +++ b/kernel/arch/xtensa/lib/strnlen_user.S @@ -0,0 +1,147 @@ +/* + * 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 <variant/core.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) + */ + +#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 +.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 + 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(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 diff --git a/kernel/arch/xtensa/lib/usercopy.S b/kernel/arch/xtensa/lib/usercopy.S new file mode 100644 index 000000000..ace1892a8 --- /dev/null +++ b/kernel/arch/xtensa/lib/usercopy.S @@ -0,0 +1,320 @@ +/* + * 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 <variant/core.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 |