diff options
author | Ralf Baechle <ralf@linux-mips.org> | 1997-01-07 02:33:00 +0000 |
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committer | <ralf@linux-mips.org> | 1997-01-07 02:33:00 +0000 |
commit | beb116954b9b7f3bb56412b2494b562f02b864b1 (patch) | |
tree | 120e997879884e1b9d93b265221b939d2ef1ade1 /arch/sparc/lib/checksum.S | |
parent | 908d4681a1dc3792ecafbe64265783a86c4cccb6 (diff) |
Import of Linux/MIPS 2.1.14
Diffstat (limited to 'arch/sparc/lib/checksum.S')
-rw-r--r-- | arch/sparc/lib/checksum.S | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/arch/sparc/lib/checksum.S b/arch/sparc/lib/checksum.S new file mode 100644 index 000000000..a71371bf8 --- /dev/null +++ b/arch/sparc/lib/checksum.S @@ -0,0 +1,439 @@ +/* checksum.S: Sparc optimized checksum code. + * + * Copyright(C) 1995 Linus Torvalds + * Copyright(C) 1995 Miguel de Icaza + * Copyright(C) 1996 David S. Miller + * + * derived from: + * Linux/Alpha checksum c-code + * Linux/ix86 inline checksum assembly + * RFC1071 Computing the Internet Checksum (esp. Jacobsons m68k code) + * David Mosberger-Tang for optimized reference c-code + * BSD4.4 portable checksum routine + */ + +#include <asm-sparc/cprefix.h> + +#define CSUM_BIGCHUNK(buf, offset, sum, t0, t1, t2, t3, t4, t5) \ + ldd [buf + offset + 0x00], t0; \ + ldd [buf + offset + 0x08], t2; \ + addxcc t0, sum, sum; \ + addxcc t1, sum, sum; \ + ldd [buf + offset + 0x10], t4; \ + addxcc t2, sum, sum; \ + addxcc t3, sum, sum; \ + ldd [buf + offset + 0x18], t0; \ + addxcc t4, sum, sum; \ + addxcc t5, sum, sum; \ + addxcc t0, sum, sum; \ + addxcc t1, sum, sum; + +#define CSUM_LASTCHUNK(buf, offset, sum, t0, t1, t2, t3) \ + ldd [buf - offset - 0x08], t0; \ + ldd [buf - offset - 0x00], t2; \ + addxcc t0, sum, sum; \ + addxcc t1, sum, sum; \ + addxcc t2, sum, sum; \ + addxcc t3, sum, sum; + + /* Do end cruft out of band to get better cache patterns. */ +csum_partial_end_cruft: + be 1f ! caller asks %o1 & 0x8 + andcc %o1, 4, %g0 ! nope, check for word remaining + ldd [%o0], %g2 ! load two + addcc %g2, %o2, %o2 ! add first word to sum + addxcc %g3, %o2, %o2 ! add second word as well + add %o0, 8, %o0 ! advance buf ptr + addx %g0, %o2, %o2 ! add in final carry + andcc %o1, 4, %g0 ! check again for word remaining +1: be 1f ! nope, skip this code + andcc %o1, 3, %o1 ! check for trailing bytes + ld [%o0], %g2 ! load it + addcc %g2, %o2, %o2 ! add to sum + add %o0, 4, %o0 ! advance buf ptr + addx %g0, %o2, %o2 ! add in final carry + andcc %o1, 3, %g0 ! check again for trailing bytes +1: be 1f ! no trailing bytes, return + addcc %o1, -1, %g0 ! only one byte remains? + bne 2f ! at least two bytes more + subcc %o1, 2, %o1 ! only two bytes more? + b 4f ! only one byte remains + or %g0, %g0, %o4 ! clear fake hword value +2: lduh [%o0], %o4 ! get hword + be 6f ! jmp if only hword remains + add %o0, 2, %o0 ! advance buf ptr either way + sll %o4, 16, %o4 ! create upper hword +4: ldub [%o0], %o5 ! get final byte + sll %o5, 8, %o5 ! put into place + or %o5, %o4, %o4 ! coalese with hword (if any) +6: addcc %o4, %o2, %o2 ! add to sum +1: retl ! get outta here + addx %g0, %o2, %o0 ! add final carry into retval + + /* Also do alignment out of band to get better cache patterns. */ +csum_partial_fix_alignment: + cmp %o1, 6 + bl cpte - 0x4 + andcc %o0, 0x2, %g0 + be 1f + andcc %o0, 0x4, %g0 + lduh [%o0 + 0x00], %g2 + sub %o1, 2, %o1 + add %o0, 2, %o0 + sll %g2, 16, %g2 + addcc %g2, %o2, %o2 + srl %o2, 16, %g3 + addx %g0, %g3, %g2 + sll %o2, 16, %o2 + sll %g2, 16, %g3 + srl %o2, 16, %o2 + andcc %o0, 0x4, %g0 + or %g3, %o2, %o2 +1: be cpa + andcc %o1, 0xffffff80, %o3 + ld [%o0 + 0x00], %g2 + sub %o1, 4, %o1 + addcc %g2, %o2, %o2 + add %o0, 4, %o0 + addx %g0, %o2, %o2 + b cpa + andcc %o1, 0xffffff80, %o3 + + /* The common case is to get called with a nicely aligned + * buffer of size 0x20. Follow the code path for that case. + */ + .globl C_LABEL(csum_partial) +C_LABEL(csum_partial): /* %o0=buf, %o1=len, %o2=sum */ + andcc %o0, 0x7, %g0 ! alignment problems? + bne csum_partial_fix_alignment ! yep, handle it + sethi %hi(cpte - 8), %g7 ! prepare table jmp ptr + andcc %o1, 0xffffff80, %o3 ! num loop iterations +cpa: be 3f ! none to do + andcc %o1, 0x70, %g1 ! clears carry flag too +5: CSUM_BIGCHUNK(%o0, 0x00, %o2, %o4, %o5, %g2, %g3, %g4, %g5) + CSUM_BIGCHUNK(%o0, 0x20, %o2, %o4, %o5, %g2, %g3, %g4, %g5) + CSUM_BIGCHUNK(%o0, 0x40, %o2, %o4, %o5, %g2, %g3, %g4, %g5) + CSUM_BIGCHUNK(%o0, 0x60, %o2, %o4, %o5, %g2, %g3, %g4, %g5) + addx %g0, %o2, %o2 ! sink in final carry + subcc %o3, 128, %o3 ! detract from loop iters + bne 5b ! more to do + add %o0, 128, %o0 ! advance buf ptr + andcc %o1, 0x70, %g1 ! clears carry flag too +3: be cpte ! nope + andcc %o1, 0xf, %g0 ! anything left at all? + srl %g1, 1, %o4 ! compute offset + sub %g7, %g1, %g7 ! adjust jmp ptr + sub %g7, %o4, %g7 ! final jmp ptr adjust + jmp %g7 + %lo(cpte - 8) ! enter the table + add %o0, %g1, %o0 ! advance buf ptr +cptbl: CSUM_LASTCHUNK(%o0, 0x68, %o2, %g2, %g3, %g4, %g5) + CSUM_LASTCHUNK(%o0, 0x58, %o2, %g2, %g3, %g4, %g5) + CSUM_LASTCHUNK(%o0, 0x48, %o2, %g2, %g3, %g4, %g5) + CSUM_LASTCHUNK(%o0, 0x38, %o2, %g2, %g3, %g4, %g5) + CSUM_LASTCHUNK(%o0, 0x28, %o2, %g2, %g3, %g4, %g5) + CSUM_LASTCHUNK(%o0, 0x18, %o2, %g2, %g3, %g4, %g5) + CSUM_LASTCHUNK(%o0, 0x08, %o2, %g2, %g3, %g4, %g5) + addx %g0, %o2, %o2 ! fetch final carry + andcc %o1, 0xf, %g0 ! anything left at all? +cpte: bne csum_partial_end_cruft ! yep, handle it + andcc %o1, 8, %g0 ! check how much +cpout: retl ! get outta here + mov %o2, %o0 ! return computed csum + + /* This aligned version executes typically in 8.5 superscalar cycles, this + * is the best I can do. I say 8.5 because the final add will pair with + * the next ldd in the main unrolled loop. Thus the pipe is always full. + */ +#define CSUMCOPY_BIGCHUNK_ALIGNED(src, dst, sum, off, t0, t1, t2, t3, t4, t5, t6, t7) \ + ldd [src + off + 0x00], t0; \ + ldd [src + off + 0x08], t2; \ + addxcc t0, sum, sum; \ + ldd [src + off + 0x10], t4; \ + addxcc t1, sum, sum; \ + ldd [src + off + 0x18], t6; \ + addxcc t2, sum, sum; \ + std t0, [dst + off + 0x00]; \ + addxcc t3, sum, sum; \ + std t2, [dst + off + 0x08]; \ + addxcc t4, sum, sum; \ + std t4, [dst + off + 0x10]; \ + addxcc t5, sum, sum; \ + std t6, [dst + off + 0x18]; \ + addxcc t6, sum, sum; \ + addxcc t7, sum, sum; + + /* 12 superscalar cycles seems to be the limit for this case, + * because of this we thus do all the ldd's together to get + * Viking MXCC into streaming mode. Ho hum... + */ +#define CSUMCOPY_BIGCHUNK(src, dst, sum, off, t0, t1, t2, t3, t4, t5, t6, t7) \ + ldd [src + off + 0x00], t0; \ + ldd [src + off + 0x08], t2; \ + ldd [src + off + 0x10], t4; \ + ldd [src + off + 0x18], t6; \ + st t0, [dst + off + 0x00]; \ + addxcc t0, sum, sum; \ + st t1, [dst + off + 0x04]; \ + addxcc t1, sum, sum; \ + st t2, [dst + off + 0x08]; \ + addxcc t2, sum, sum; \ + st t3, [dst + off + 0x0c]; \ + addxcc t3, sum, sum; \ + st t4, [dst + off + 0x10]; \ + addxcc t4, sum, sum; \ + st t5, [dst + off + 0x14]; \ + addxcc t5, sum, sum; \ + st t6, [dst + off + 0x18]; \ + addxcc t6, sum, sum; \ + st t7, [dst + off + 0x1c]; \ + addxcc t7, sum, sum; + + /* Yuck, 6 superscalar cycles... */ +#define CSUMCOPY_LASTCHUNK(src, dst, sum, off, t0, t1, t2, t3) \ + ldd [src - off - 0x08], t0; \ + ldd [src - off - 0x00], t2; \ + addxcc t0, sum, sum; \ + st t0, [dst - off - 0x08]; \ + addxcc t1, sum, sum; \ + st t1, [dst - off - 0x04]; \ + addxcc t2, sum, sum; \ + st t2, [dst - off - 0x00]; \ + addxcc t3, sum, sum; \ + st t3, [dst - off + 0x04]; + + /* Handle the end cruft code out of band for better cache patterns. */ +cc_end_cruft: + be 1f + andcc %o3, 4, %g0 + ldd [%o0 + 0x00], %g2 + add %o1, 8, %o1 + addcc %g2, %g7, %g7 + add %o0, 8, %o0 + addxcc %g3, %g7, %g7 + st %g2, [%o1 - 0x08] + addx %g0, %g7, %g7 + andcc %o3, 4, %g0 + st %g3, [%o1 - 0x04] +1: be 1f + andcc %o3, 3, %o3 + ld [%o0 + 0x00], %g2 + add %o1, 4, %o1 + addcc %g2, %g7, %g7 + st %g2, [%o1 - 0x04] + addx %g0, %g7, %g7 + add %o0, 4, %o0 + andcc %o3, 3, %g0 +1: be 1f + addcc %o3, -1, %g0 + bne 2f + subcc %o3, 2, %o3 + b 4f + or %g0, %g0, %o4 +2: lduh [%o0 + 0x00], %o4 + add %o0, 2, %o0 + sth %o4, [%o1 + 0x00] + be 6f + add %o1, 2, %o1 + sll %o4, 16, %o4 +4: ldub [%o0 + 0x00], %o5 + stb %o5, [%o1 + 0x00] + sll %o5, 8, %o5 + or %o5, %o4, %o4 +6: addcc %o4, %g7, %g7 +1: retl + addx %g0, %g7, %o0 + + /* Also, handle the alignment code out of band. */ +cc_dword_align: + cmp %g1, 6 + bl,a ccte + andcc %g1, 0xf, %o3 + andcc %o0, 0x1, %g0 + bne ccslow + andcc %o0, 0x2, %g0 + be 1f + andcc %o0, 0x4, %g0 + lduh [%o0 + 0x00], %g2 + sub %g1, 2, %g1 + sth %g2, [%o1 + 0x00] + add %o0, 2, %o0 + sll %g2, 16, %g2 + addcc %g2, %g7, %g7 + add %o1, 2, %o1 + srl %g7, 16, %g3 + addx %g0, %g3, %g2 + sll %g7, 16, %g7 + sll %g2, 16, %g3 + srl %g7, 16, %g7 + andcc %o0, 0x4, %g0 + or %g3, %g7, %g7 +1: be 3f + andcc %g1, 0xffffff80, %g0 + ld [%o0 + 0x00], %g2 + sub %g1, 4, %g1 + st %g2, [%o1 + 0x00] + add %o0, 4, %o0 + addcc %g2, %g7, %g7 + add %o1, 4, %o1 + addx %g0, %g7, %g7 + b 3f + andcc %g1, 0xffffff80, %g0 + + /* Sun, you just can't beat me, you just can't. Stop trying, + * give up. I'm serious, I am going to kick the living shit + * out of you, game over, lights out. + */ + .align 8 + .globl C_LABEL(csum_partial_copy) +C_LABEL(csum_partial_copy): /* %o0=src, %o1=dest, %o2=len, %o3=sum */ + xor %o0, %o1, %o4 ! get changing bits + mov %o2, %g1 ! free up %o2 + andcc %o4, 3, %g0 ! check for mismatched alignment + bne ccslow ! better this than unaligned/fixups + andcc %o0, 7, %g0 ! need to align things? + mov %o3, %g7 ! free up %o3 + bne cc_dword_align ! yes, we check for short lengths there + andcc %g1, 0xffffff80, %g0 ! can we use unrolled loop? +3: be 3f ! nope, less than one loop remains + andcc %o1, 4, %g0 ! dest aligned on 4 or 8 byte boundry? + be ccdbl + 4 ! 8 byte aligned, kick ass +5: CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x00,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x20,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x40,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x60,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + sub %g1, 128, %g1 ! detract from length + addx %g0, %g7, %g7 ! add in last carry bit + andcc %g1, 0xffffff80, %g0 ! more to csum? + add %o0, 128, %o0 ! advance src ptr + bne 5b ! we did not go negative, continue looping + add %o1, 128, %o1 ! advance dest ptr +3: andcc %g1, 0x70, %o2 ! can use table? +ccmerge:be ccte ! nope, go and check for end cruft + andcc %g1, 0xf, %o3 ! get low bits of length (clears carry btw) + srl %o2, 1, %o4 ! begin negative offset computation + sethi %hi(ccte - 8), %o5 ! set up table ptr end + add %o0, %o2, %o0 ! advance src ptr + sub %o5, %o4, %o5 ! continue table calculation + sll %o2, 1, %g2 ! constant multiplies are fun... + sub %o5, %g2, %o5 ! some more adjustments + jmp %o5 + %lo(ccte - 8) ! jump into it, duff style, wheee... + add %o1, %o2, %o1 ! advance dest ptr (carry is clear btw) +cctbl: CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x68,%g2,%g3,%g4,%g5) + CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x58,%g2,%g3,%g4,%g5) + CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x48,%g2,%g3,%g4,%g5) + CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x38,%g2,%g3,%g4,%g5) + CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x28,%g2,%g3,%g4,%g5) + CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x18,%g2,%g3,%g4,%g5) + CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x08,%g2,%g3,%g4,%g5) + addx %g0, %g7, %g7 + andcc %o3, 0xf, %g0 ! check for low bits set +ccte: bne cc_end_cruft ! something left, handle it out of band + andcc %o3, 8, %g0 ! begin checks for that code + retl ! return + mov %g7, %o0 ! give em the computed checksum +ccdbl: CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x00,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x20,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x40,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x60,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3) + sub %g1, 128, %g1 ! detract from length + addx %g0, %g7, %g7 ! add in last carry bit + andcc %g1, 0xffffff80, %g0 ! more to csum? + add %o0, 128, %o0 ! advance src ptr + bne ccdbl ! we did not go negative, continue looping + add %o1, 128, %o1 ! advance dest ptr + b ccmerge ! finish it off, above + andcc %g1, 0x70, %o2 ! can use table? (clears carry btw) + +ccslow: + save %sp, -104, %sp + mov %i0, %g2 + mov %g2, %o4 + orcc %i2, %g0, %o5 + ble .LL37 + mov 0, %o3 + andcc %g2, 1, %g3 + be .LL50 + sra %o5, 1, %o1 + ldub [%g2], %o3 + add %i2, -1, %o5 + add %g2, 1, %o4 + sra %o5, 1, %o1 +.LL50: + cmp %o1, 0 + be .LL39 + andcc %o4, 2, %g0 + be,a .LL51 + sra %o1, 1, %o1 + add %o1, -1, %o1 + lduh [%o4], %o0 + add %o5, -2, %o5 + add %o3, %o0, %o3 + add %o4, 2, %o4 + sra %o1, 1, %o1 +.LL51: + cmp %o1, 0 + be .LL41 + mov 0, %o2 +.LL42: + ld [%o4], %o0 + add %o3, %o2, %o3 + add %o3, %o0, %o3 + cmp %o3, %o0 + addx %g0, 0, %o2 + addcc %o1, -1, %o1 + bne .LL42 + add %o4, 4, %o4 + add %o3, %o2, %o3 + sethi %hi(65535), %o0 + or %o0, %lo(65535), %o0 + and %o3, %o0, %o0 + srl %o3, 16, %o1 + add %o0, %o1, %o3 +.LL41: + andcc %o5, 2, %g0 + be .LL52 + andcc %o5, 1, %g0 + lduh [%o4], %o0 + add %o3, %o0, %o3 + add %o4, 2, %o4 +.LL39: + andcc %o5, 1, %g0 +.LL52: + be .LL53 + sethi %hi(65535), %o0 + ldub [%o4], %o0 + sll %o0, 8, %o0 + add %o3, %o0, %o3 + sethi %hi(65535), %o0 +.LL53: + or %o0, %lo(65535), %o0 + and %o3, %o0, %o2 + srl %o3, 16, %o1 + add %o2, %o1, %o1 + and %o1, %o0, %o2 + srl %o1, 16, %o1 + add %o2, %o1, %o1 + and %o1, %o0, %o0 + srl %o1, 16, %o1 + add %o0, %o1, %o1 + sll %o1, 16, %o0 + cmp %g3, 0 + be .LL37 + srl %o0, 16, %o3 + srl %o0, 24, %o1 + and %o3, 255, %o0 + sll %o0, 8, %o0 + or %o1, %o0, %o3 +.LL37: + add %o3, %i3, %o1 + sethi %hi(65535), %o0 + or %o0, %lo(65535), %o0 + and %o1, %o0, %o0 + srl %o1, 16, %o1 + add %o0, %o1, %i0 + mov %i1, %o0 + mov %g2, %o1 + call C_LABEL(__memcpy) + mov %i2, %o2 + ret + restore |