+++ /dev/null
-/*
- * 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
- *
- * Authors: Jorge Cwik, <jorge@laser.satlink.net>
- * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
- * Tom May, <ftom@netcom.com>
- * Pentium Pro/II routines:
- * Alexander Kjeldaas <astor@guardian.no>
- * Finn Arne Gangstad <finnag@guardian.no>
- * Lots of code moved from tcp.c and ip.c; see those files
- * for more names.
- *
- * Changes: Ingo Molnar, converted csum_partial_copy() to 2.1 exception
- * handling.
- * Andi Kleen, add zeroing on error
- * converted to pure assembler
- * Hirokazu Takata,Hiroyuki Kondo rewrite for the m32r architecture.
- *
- * 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/linkage.h>
-#include <asm/assembler.h>
-#include <asm/errno.h>
-
-/*
- * computes a partial checksum, e.g. for TCP/UDP fragments
- */
-
-/*
-unsigned int csum_partial(const unsigned char * buff, int len, unsigned int sum)
- */
-
-
-#ifdef CONFIG_ISA_DUAL_ISSUE
-
- /*
- * Experiments with Ethernet and SLIP connections show that buff
- * is aligned on either a 2-byte or 4-byte boundary. We get at
- * least a twofold speedup on 486 and Pentium if it is 4-byte aligned.
- * Fortunately, it is easy to convert 2-byte alignment to 4-byte
- * alignment for the unrolled loop.
- */
-
- .text
-ENTRY(csum_partial)
- ; Function args
- ; r0: unsigned char *buff
- ; r1: int len
- ; r2: unsigned int sum
-
- push r2 || ldi r2, #0
- and3 r7, r0, #1 ; Check alignment.
- beqz r7, 1f ; Jump if alignment is ok.
- ; 1-byte mis aligned
- ldub r4, @r0 || addi r0, #1
- ; clear c-bit || Alignment uses up bytes.
- cmp r0, r0 || addi r1, #-1
- ldi r3, #0 || addx r2, r4
- addx r2, r3
- .fillinsn
-1:
- and3 r4, r0, #2 ; Check alignment.
- beqz r4, 2f ; Jump if alignment is ok.
- ; clear c-bit || Alignment uses up two bytes.
- cmp r0, r0 || addi r1, #-2
- bgtz r1, 1f ; Jump if we had at least two bytes.
- bra 4f || addi r1, #2
- .fillinsn ; len(r1) was < 2. Deal with it.
-1:
- ; 2-byte aligned
- lduh r4, @r0 || ldi r3, #0
- addx r2, r4 || addi r0, #2
- addx r2, r3
- .fillinsn
-2:
- ; 4-byte aligned
- cmp r0, r0 ; clear c-bit
- srl3 r6, r1, #5
- beqz r6, 2f
- .fillinsn
-
-1: ld r3, @r0+
- ld r4, @r0+ ; +4
- ld r5, @r0+ ; +8
- ld r3, @r0+ || addx r2, r3 ; +12
- ld r4, @r0+ || addx r2, r4 ; +16
- ld r5, @r0+ || addx r2, r5 ; +20
- ld r3, @r0+ || addx r2, r3 ; +24
- ld r4, @r0+ || addx r2, r4 ; +28
- addx r2, r5 || addi r6, #-1
- addx r2, r3
- addx r2, r4
- bnez r6, 1b
-
- addx r2, r6 ; r6=0
- cmp r0, r0 ; This clears c-bit
- .fillinsn
-2: and3 r6, r1, #0x1c ; withdraw len
- beqz r6, 4f
- srli r6, #2
- .fillinsn
-
-3: ld r4, @r0+ || addi r6, #-1
- addx r2, r4
- bnez r6, 3b
-
- addx r2, r6 ; r6=0
- cmp r0, r0 ; This clears c-bit
- .fillinsn
-4: and3 r1, r1, #3
- beqz r1, 7f ; if len == 0 goto end
- and3 r6, r1, #2
- beqz r6, 5f ; if len < 2 goto 5f(1byte)
- lduh r4, @r0 || addi r0, #2
- addi r1, #-2 || slli r4, #16
- addx r2, r4
- beqz r1, 6f
- .fillinsn
-5: ldub r4, @r0 || ldi r1, #0
-#ifndef __LITTLE_ENDIAN__
- slli r4, #8
-#endif
- addx r2, r4
- .fillinsn
-6: addx r2, r1
- .fillinsn
-7:
- and3 r0, r2, #0xffff
- srli r2, #16
- add r0, r2
- srl3 r2, r0, #16
- beqz r2, 1f
- addi r0, #1
- and3 r0, r0, #0xffff
- .fillinsn
-1:
- beqz r7, 1f ; swap the upper byte for the lower
- and3 r2, r0, #0xff
- srl3 r0, r0, #8
- slli r2, #8
- or r0, r2
- .fillinsn
-1:
- pop r2 || cmp r0, r0
- addx r0, r2 || ldi r2, #0
- addx r0, r2
- jmp r14
-
-#else /* not CONFIG_ISA_DUAL_ISSUE */
-
- /*
- * Experiments with Ethernet and SLIP connections show that buff
- * is aligned on either a 2-byte or 4-byte boundary. We get at
- * least a twofold speedup on 486 and Pentium if it is 4-byte aligned.
- * Fortunately, it is easy to convert 2-byte alignment to 4-byte
- * alignment for the unrolled loop.
- */
-
- .text
-ENTRY(csum_partial)
- ; Function args
- ; r0: unsigned char *buff
- ; r1: int len
- ; r2: unsigned int sum
-
- push r2
- ldi r2, #0
- and3 r7, r0, #1 ; Check alignment.
- beqz r7, 1f ; Jump if alignment is ok.
- ; 1-byte mis aligned
- ldub r4, @r0
- addi r0, #1
- addi r1, #-1 ; Alignment uses up bytes.
- cmp r0, r0 ; clear c-bit
- ldi r3, #0
- addx r2, r4
- addx r2, r3
- .fillinsn
-1:
- and3 r4, r0, #2 ; Check alignment.
- beqz r4, 2f ; Jump if alignment is ok.
- addi r1, #-2 ; Alignment uses up two bytes.
- cmp r0, r0 ; clear c-bit
- bgtz r1, 1f ; Jump if we had at least two bytes.
- addi r1, #2 ; len(r1) was < 2. Deal with it.
- bra 4f
- .fillinsn
-1:
- ; 2-byte aligned
- lduh r4, @r0
- addi r0, #2
- ldi r3, #0
- addx r2, r4
- addx r2, r3
- .fillinsn
-2:
- ; 4-byte aligned
- cmp r0, r0 ; clear c-bit
- srl3 r6, r1, #5
- beqz r6, 2f
- .fillinsn
-
-1: ld r3, @r0+
- ld r4, @r0+ ; +4
- ld r5, @r0+ ; +8
- addx r2, r3
- addx r2, r4
- addx r2, r5
- ld r3, @r0+ ; +12
- ld r4, @r0+ ; +16
- ld r5, @r0+ ; +20
- addx r2, r3
- addx r2, r4
- addx r2, r5
- ld r3, @r0+ ; +24
- ld r4, @r0+ ; +28
- addi r6, #-1
- addx r2, r3
- addx r2, r4
- bnez r6, 1b
- addx r2, r6 ; r6=0
- cmp r0, r0 ; This clears c-bit
- .fillinsn
-
-2: and3 r6, r1, #0x1c ; withdraw len
- beqz r6, 4f
- srli r6, #2
- .fillinsn
-
-3: ld r4, @r0+
- addi r6, #-1
- addx r2, r4
- bnez r6, 3b
- addx r2, r6 ; r6=0
- cmp r0, r0 ; This clears c-bit
- .fillinsn
-
-4: and3 r1, r1, #3
- beqz r1, 7f ; if len == 0 goto end
- and3 r6, r1, #2
- beqz r6, 5f ; if len < 2 goto 5f(1byte)
-
- lduh r4, @r0
- addi r0, #2
- addi r1, #-2
- slli r4, #16
- addx r2, r4
- beqz r1, 6f
- .fillinsn
-5: ldub r4, @r0
-#ifndef __LITTLE_ENDIAN__
- slli r4, #8
-#endif
- addx r2, r4
- .fillinsn
-6: ldi r5, #0
- addx r2, r5
- .fillinsn
-7:
- and3 r0, r2, #0xffff
- srli r2, #16
- add r0, r2
- srl3 r2, r0, #16
- beqz r2, 1f
- addi r0, #1
- and3 r0, r0, #0xffff
- .fillinsn
-1:
- beqz r7, 1f
- mv r2, r0
- srl3 r0, r2, #8
- and3 r2, r2, #0xff
- slli r2, #8
- or r0, r2
- .fillinsn
-1:
- pop r2
- cmp r0, r0
- addx r0, r2
- ldi r2, #0
- addx r0, r2
- jmp r14
-
-#endif /* not CONFIG_ISA_DUAL_ISSUE */
-
-/*
-unsigned int csum_partial_copy_generic (const char *src, char *dst,
- int len, int sum, int *src_err_ptr, int *dst_err_ptr)
- */
-
-/*
- * 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 all access types.
- *
- * FIXME: could someone double-check whether I haven't mixed up some SRC and
- * DST definitions? It's damn hard to trigger all cases. I hope I got
- * them all but there's no guarantee.
- */
-
-ENTRY(csum_partial_copy_generic)
- nop
- nop
- nop
- nop
- jmp r14
- nop
- nop
- nop
-
- .end
projects / linux-2.6-microblaze.git / blobdiff