/* SPDX-License-Identifier: GPL-2.0 */ /* checksum.S: Sparc optimized checksum code. * * Copyright(C) 1995 Linus Torvalds * Copyright(C) 1995 Miguel de Icaza * Copyright(C) 1996 David S. Miller * Copyright(C) 1997 Jakub Jelinek * * 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 #include #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 csum_partial EXPORT_SYMBOL(csum_partial) 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 /* Work around cpp -rob */ #define ALLOC #alloc #define EXECINSTR #execinstr #define EX(x,y) \ 98: x,y; \ .section __ex_table,ALLOC; \ .align 4; \ .word 98b, cc_fault; \ .text; \ .align 4 #define EXT(start,end) \ .section __ex_table,ALLOC; \ .align 4; \ .word start, 0, end, cc_fault; \ .text; \ .align 4 /* 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. * If you change these macros (including order of instructions), * please check the fixup code below as well. */ #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 EX(ldd [%o0 + 0x00], %g2) add %o1, 8, %o1 addcc %g2, %g7, %g7 add %o0, 8, %o0 addxcc %g3, %g7, %g7 EX(st %g2, [%o1 - 0x08]) addx %g0, %g7, %g7 andcc %o3, 4, %g0 EX(st %g3, [%o1 - 0x04]) 1: be 1f andcc %o3, 3, %o3 EX(ld [%o0 + 0x00], %g2) add %o1, 4, %o1 addcc %g2, %g7, %g7 EX(st %g2, [%o1 - 0x04]) addx %g0, %g7, %g7 andcc %o3, 3, %g0 add %o0, 4, %o0 1: be 1f addcc %o3, -1, %g0 bne 2f subcc %o3, 2, %o3 b 4f or %g0, %g0, %o4 2: EX(lduh [%o0 + 0x00], %o4) add %o0, 2, %o0 EX(sth %o4, [%o1 + 0x00]) be 6f add %o1, 2, %o1 sll %o4, 16, %o4 4: EX(ldub [%o0 + 0x00], %o5) EX(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, 16 bge 1f srl %g1, 1, %o3 2: cmp %o3, 0 be,a ccte andcc %g1, 0xf, %o3 andcc %o3, %o0, %g0 ! Check %o0 only (%o1 has the same last 2 bits) be,a 2b srl %o3, 1, %o3 1: andcc %o0, 0x1, %g0 bne ccslow andcc %o0, 0x2, %g0 be 1f andcc %o0, 0x4, %g0 EX(lduh [%o0 + 0x00], %g4) sub %g1, 2, %g1 EX(sth %g4, [%o1 + 0x00]) add %o0, 2, %o0 sll %g4, 16, %g4 addcc %g4, %g7, %g7 add %o1, 2, %o1 srl %g7, 16, %g3 addx %g0, %g3, %g4 sll %g7, 16, %g7 sll %g4, 16, %g3 srl %g7, 16, %g7 andcc %o0, 0x4, %g0 or %g3, %g7, %g7 1: be 3f andcc %g1, 0xffffff80, %g0 EX(ld [%o0 + 0x00], %g4) sub %g1, 4, %g1 EX(st %g4, [%o1 + 0x00]) add %o0, 4, %o0 addcc %g4, %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 __csum_partial_copy_sparc_generic EXPORT_SYMBOL(__csum_partial_copy_sparc_generic) __csum_partial_copy_sparc_generic: /* %o0=src, %o1=dest, %g1=len, %g7=sum */ xor %o0, %o1, %o4 ! get changing bits andcc %o4, 3, %g0 ! check for mismatched alignment bne ccslow ! better this than unaligned/fixups andcc %o0, 7, %g0 ! need to align things? 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 boundary? 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) 10: EXT(5b, 10b) ! note for exception handling 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(12f), %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(12f) ! 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) 12: EXT(cctbl, 12b) ! note for exception table handling 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) 11: EXT(ccdbl, 11b) ! note for exception table handling 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: cmp %g1, 0 mov 0, %g5 bleu 4f andcc %o0, 1, %o5 be,a 1f srl %g1, 1, %g4 sub %g1, 1, %g1 EX(ldub [%o0], %g5) add %o0, 1, %o0 EX(stb %g5, [%o1]) srl %g1, 1, %g4 add %o1, 1, %o1 1: cmp %g4, 0 be,a 3f andcc %g1, 1, %g0 andcc %o0, 2, %g0 be,a 1f srl %g4, 1, %g4 EX(lduh [%o0], %o4) sub %g1, 2, %g1 srl %o4, 8, %g2 sub %g4, 1, %g4 EX(stb %g2, [%o1]) add %o4, %g5, %g5 EX(stb %o4, [%o1 + 1]) add %o0, 2, %o0 srl %g4, 1, %g4 add %o1, 2, %o1 1: cmp %g4, 0 be,a 2f andcc %g1, 2, %g0 EX(ld [%o0], %o4) 5: srl %o4, 24, %g2 srl %o4, 16, %g3 EX(stb %g2, [%o1]) srl %o4, 8, %g2 EX(stb %g3, [%o1 + 1]) add %o0, 4, %o0 EX(stb %g2, [%o1 + 2]) addcc %o4, %g5, %g5 EX(stb %o4, [%o1 + 3]) addx %g5, %g0, %g5 ! I am now to lazy to optimize this (question it add %o1, 4, %o1 ! is worthy). Maybe some day - with the sll/srl subcc %g4, 1, %g4 ! tricks bne,a 5b EX(ld [%o0], %o4) sll %g5, 16, %g2 srl %g5, 16, %g5 srl %g2, 16, %g2 andcc %g1, 2, %g0 add %g2, %g5, %g5 2: be,a 3f andcc %g1, 1, %g0 EX(lduh [%o0], %o4) andcc %g1, 1, %g0 srl %o4, 8, %g2 add %o0, 2, %o0 EX(stb %g2, [%o1]) add %g5, %o4, %g5 EX(stb %o4, [%o1 + 1]) add %o1, 2, %o1 3: be,a 1f sll %g5, 16, %o4 EX(ldub [%o0], %g2) sll %g2, 8, %o4 EX(stb %g2, [%o1]) add %g5, %o4, %g5 sll %g5, 16, %o4 1: addcc %o4, %g5, %g5 srl %g5, 16, %o4 addx %g0, %o4, %g5 orcc %o5, %g0, %g0 be 4f srl %g5, 8, %o4 and %g5, 0xff, %g2 and %o4, 0xff, %o4 sll %g2, 8, %g2 or %g2, %o4, %g5 4: addcc %g7, %g5, %g7 retl addx %g0, %g7, %o0 /* We do these strange calculations for the csum_*_from_user case only, ie. * we only bother with faults on loads... */ cc_fault: retl clr %o0