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cfd5fa7021
trivial - we don't even look at instruction offsets in the handler Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
458 lines
14 KiB
ArmAsm
458 lines
14 KiB
ArmAsm
/* SPDX-License-Identifier: GPL-2.0 */
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/* checksum.S: Sparc optimized checksum code.
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*
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* Copyright(C) 1995 Linus Torvalds
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* Copyright(C) 1995 Miguel de Icaza
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* Copyright(C) 1996 David S. Miller
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* Copyright(C) 1997 Jakub Jelinek
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*
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* derived from:
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* Linux/Alpha checksum c-code
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* Linux/ix86 inline checksum assembly
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* RFC1071 Computing the Internet Checksum (esp. Jacobsons m68k code)
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* David Mosberger-Tang for optimized reference c-code
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* BSD4.4 portable checksum routine
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*/
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#include <asm/errno.h>
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#include <asm/export.h>
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#define CSUM_BIGCHUNK(buf, offset, sum, t0, t1, t2, t3, t4, t5) \
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ldd [buf + offset + 0x00], t0; \
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ldd [buf + offset + 0x08], t2; \
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addxcc t0, sum, sum; \
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addxcc t1, sum, sum; \
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ldd [buf + offset + 0x10], t4; \
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addxcc t2, sum, sum; \
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addxcc t3, sum, sum; \
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ldd [buf + offset + 0x18], t0; \
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addxcc t4, sum, sum; \
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addxcc t5, sum, sum; \
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addxcc t0, sum, sum; \
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addxcc t1, sum, sum;
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#define CSUM_LASTCHUNK(buf, offset, sum, t0, t1, t2, t3) \
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ldd [buf - offset - 0x08], t0; \
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ldd [buf - offset - 0x00], t2; \
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addxcc t0, sum, sum; \
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addxcc t1, sum, sum; \
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addxcc t2, sum, sum; \
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addxcc t3, sum, sum;
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/* Do end cruft out of band to get better cache patterns. */
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csum_partial_end_cruft:
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be 1f ! caller asks %o1 & 0x8
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andcc %o1, 4, %g0 ! nope, check for word remaining
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ldd [%o0], %g2 ! load two
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addcc %g2, %o2, %o2 ! add first word to sum
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addxcc %g3, %o2, %o2 ! add second word as well
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add %o0, 8, %o0 ! advance buf ptr
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addx %g0, %o2, %o2 ! add in final carry
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andcc %o1, 4, %g0 ! check again for word remaining
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1: be 1f ! nope, skip this code
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andcc %o1, 3, %o1 ! check for trailing bytes
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ld [%o0], %g2 ! load it
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addcc %g2, %o2, %o2 ! add to sum
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add %o0, 4, %o0 ! advance buf ptr
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addx %g0, %o2, %o2 ! add in final carry
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andcc %o1, 3, %g0 ! check again for trailing bytes
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1: be 1f ! no trailing bytes, return
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addcc %o1, -1, %g0 ! only one byte remains?
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bne 2f ! at least two bytes more
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subcc %o1, 2, %o1 ! only two bytes more?
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b 4f ! only one byte remains
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or %g0, %g0, %o4 ! clear fake hword value
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2: lduh [%o0], %o4 ! get hword
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be 6f ! jmp if only hword remains
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add %o0, 2, %o0 ! advance buf ptr either way
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sll %o4, 16, %o4 ! create upper hword
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4: ldub [%o0], %o5 ! get final byte
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sll %o5, 8, %o5 ! put into place
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or %o5, %o4, %o4 ! coalese with hword (if any)
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6: addcc %o4, %o2, %o2 ! add to sum
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1: retl ! get outta here
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addx %g0, %o2, %o0 ! add final carry into retval
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/* Also do alignment out of band to get better cache patterns. */
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csum_partial_fix_alignment:
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cmp %o1, 6
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bl cpte - 0x4
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andcc %o0, 0x2, %g0
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be 1f
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andcc %o0, 0x4, %g0
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lduh [%o0 + 0x00], %g2
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sub %o1, 2, %o1
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add %o0, 2, %o0
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sll %g2, 16, %g2
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addcc %g2, %o2, %o2
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srl %o2, 16, %g3
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addx %g0, %g3, %g2
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sll %o2, 16, %o2
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sll %g2, 16, %g3
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srl %o2, 16, %o2
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andcc %o0, 0x4, %g0
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or %g3, %o2, %o2
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1: be cpa
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andcc %o1, 0xffffff80, %o3
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ld [%o0 + 0x00], %g2
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sub %o1, 4, %o1
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addcc %g2, %o2, %o2
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add %o0, 4, %o0
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addx %g0, %o2, %o2
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b cpa
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andcc %o1, 0xffffff80, %o3
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/* The common case is to get called with a nicely aligned
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* buffer of size 0x20. Follow the code path for that case.
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*/
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.globl csum_partial
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EXPORT_SYMBOL(csum_partial)
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csum_partial: /* %o0=buf, %o1=len, %o2=sum */
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andcc %o0, 0x7, %g0 ! alignment problems?
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bne csum_partial_fix_alignment ! yep, handle it
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sethi %hi(cpte - 8), %g7 ! prepare table jmp ptr
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andcc %o1, 0xffffff80, %o3 ! num loop iterations
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cpa: be 3f ! none to do
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andcc %o1, 0x70, %g1 ! clears carry flag too
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5: CSUM_BIGCHUNK(%o0, 0x00, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
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CSUM_BIGCHUNK(%o0, 0x20, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
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CSUM_BIGCHUNK(%o0, 0x40, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
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CSUM_BIGCHUNK(%o0, 0x60, %o2, %o4, %o5, %g2, %g3, %g4, %g5)
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addx %g0, %o2, %o2 ! sink in final carry
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subcc %o3, 128, %o3 ! detract from loop iters
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bne 5b ! more to do
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add %o0, 128, %o0 ! advance buf ptr
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andcc %o1, 0x70, %g1 ! clears carry flag too
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3: be cpte ! nope
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andcc %o1, 0xf, %g0 ! anything left at all?
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srl %g1, 1, %o4 ! compute offset
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sub %g7, %g1, %g7 ! adjust jmp ptr
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sub %g7, %o4, %g7 ! final jmp ptr adjust
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jmp %g7 + %lo(cpte - 8) ! enter the table
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add %o0, %g1, %o0 ! advance buf ptr
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cptbl: CSUM_LASTCHUNK(%o0, 0x68, %o2, %g2, %g3, %g4, %g5)
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CSUM_LASTCHUNK(%o0, 0x58, %o2, %g2, %g3, %g4, %g5)
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CSUM_LASTCHUNK(%o0, 0x48, %o2, %g2, %g3, %g4, %g5)
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CSUM_LASTCHUNK(%o0, 0x38, %o2, %g2, %g3, %g4, %g5)
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CSUM_LASTCHUNK(%o0, 0x28, %o2, %g2, %g3, %g4, %g5)
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CSUM_LASTCHUNK(%o0, 0x18, %o2, %g2, %g3, %g4, %g5)
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CSUM_LASTCHUNK(%o0, 0x08, %o2, %g2, %g3, %g4, %g5)
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addx %g0, %o2, %o2 ! fetch final carry
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andcc %o1, 0xf, %g0 ! anything left at all?
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cpte: bne csum_partial_end_cruft ! yep, handle it
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andcc %o1, 8, %g0 ! check how much
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cpout: retl ! get outta here
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mov %o2, %o0 ! return computed csum
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/* Work around cpp -rob */
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#define ALLOC #alloc
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#define EXECINSTR #execinstr
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#define EX(x,y) \
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98: x,y; \
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.section __ex_table,ALLOC; \
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.align 4; \
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.word 98b, cc_fault; \
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.text; \
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.align 4
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/* This aligned version executes typically in 8.5 superscalar cycles, this
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* is the best I can do. I say 8.5 because the final add will pair with
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* the next ldd in the main unrolled loop. Thus the pipe is always full.
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* If you change these macros (including order of instructions),
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* please check the fixup code below as well.
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*/
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#define CSUMCOPY_BIGCHUNK_ALIGNED(src, dst, sum, off, t0, t1, t2, t3, t4, t5, t6, t7) \
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EX(ldd [src + off + 0x00], t0); \
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EX(ldd [src + off + 0x08], t2); \
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addxcc t0, sum, sum; \
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EX(ldd [src + off + 0x10], t4); \
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addxcc t1, sum, sum; \
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EX(ldd [src + off + 0x18], t6); \
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addxcc t2, sum, sum; \
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EX(std t0, [dst + off + 0x00]); \
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addxcc t3, sum, sum; \
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EX(std t2, [dst + off + 0x08]); \
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addxcc t4, sum, sum; \
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EX(std t4, [dst + off + 0x10]); \
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addxcc t5, sum, sum; \
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EX(std t6, [dst + off + 0x18]); \
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addxcc t6, sum, sum; \
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addxcc t7, sum, sum;
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/* 12 superscalar cycles seems to be the limit for this case,
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* because of this we thus do all the ldd's together to get
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* Viking MXCC into streaming mode. Ho hum...
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*/
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#define CSUMCOPY_BIGCHUNK(src, dst, sum, off, t0, t1, t2, t3, t4, t5, t6, t7) \
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EX(ldd [src + off + 0x00], t0); \
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EX(ldd [src + off + 0x08], t2); \
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EX(ldd [src + off + 0x10], t4); \
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EX(ldd [src + off + 0x18], t6); \
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EX(st t0, [dst + off + 0x00]); \
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addxcc t0, sum, sum; \
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EX(st t1, [dst + off + 0x04]); \
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addxcc t1, sum, sum; \
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EX(st t2, [dst + off + 0x08]); \
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addxcc t2, sum, sum; \
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EX(st t3, [dst + off + 0x0c]); \
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addxcc t3, sum, sum; \
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EX(st t4, [dst + off + 0x10]); \
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addxcc t4, sum, sum; \
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EX(st t5, [dst + off + 0x14]); \
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addxcc t5, sum, sum; \
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EX(st t6, [dst + off + 0x18]); \
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addxcc t6, sum, sum; \
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EX(st t7, [dst + off + 0x1c]); \
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addxcc t7, sum, sum;
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/* Yuck, 6 superscalar cycles... */
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#define CSUMCOPY_LASTCHUNK(src, dst, sum, off, t0, t1, t2, t3) \
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EX(ldd [src - off - 0x08], t0); \
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EX(ldd [src - off - 0x00], t2); \
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addxcc t0, sum, sum; \
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EX(st t0, [dst - off - 0x08]); \
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addxcc t1, sum, sum; \
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EX(st t1, [dst - off - 0x04]); \
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addxcc t2, sum, sum; \
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EX(st t2, [dst - off - 0x00]); \
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addxcc t3, sum, sum; \
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EX(st t3, [dst - off + 0x04]);
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/* Handle the end cruft code out of band for better cache patterns. */
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cc_end_cruft:
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be 1f
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andcc %o3, 4, %g0
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EX(ldd [%o0 + 0x00], %g2)
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add %o1, 8, %o1
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addcc %g2, %g7, %g7
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add %o0, 8, %o0
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addxcc %g3, %g7, %g7
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EX(st %g2, [%o1 - 0x08])
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addx %g0, %g7, %g7
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andcc %o3, 4, %g0
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EX(st %g3, [%o1 - 0x04])
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1: be 1f
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andcc %o3, 3, %o3
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EX(ld [%o0 + 0x00], %g2)
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add %o1, 4, %o1
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addcc %g2, %g7, %g7
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EX(st %g2, [%o1 - 0x04])
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addx %g0, %g7, %g7
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andcc %o3, 3, %g0
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add %o0, 4, %o0
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1: be 1f
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addcc %o3, -1, %g0
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bne 2f
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subcc %o3, 2, %o3
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b 4f
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or %g0, %g0, %o4
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2: EX(lduh [%o0 + 0x00], %o4)
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add %o0, 2, %o0
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EX(sth %o4, [%o1 + 0x00])
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be 6f
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add %o1, 2, %o1
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sll %o4, 16, %o4
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4: EX(ldub [%o0 + 0x00], %o5)
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EX(stb %o5, [%o1 + 0x00])
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sll %o5, 8, %o5
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or %o5, %o4, %o4
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6: addcc %o4, %g7, %g7
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1: retl
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addx %g0, %g7, %o0
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/* Also, handle the alignment code out of band. */
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cc_dword_align:
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cmp %g1, 16
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bge 1f
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srl %g1, 1, %o3
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2: cmp %o3, 0
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be,a ccte
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andcc %g1, 0xf, %o3
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andcc %o3, %o0, %g0 ! Check %o0 only (%o1 has the same last 2 bits)
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be,a 2b
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srl %o3, 1, %o3
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1: andcc %o0, 0x1, %g0
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bne ccslow
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andcc %o0, 0x2, %g0
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be 1f
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andcc %o0, 0x4, %g0
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EX(lduh [%o0 + 0x00], %g4)
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sub %g1, 2, %g1
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EX(sth %g4, [%o1 + 0x00])
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add %o0, 2, %o0
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sll %g4, 16, %g4
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addcc %g4, %g7, %g7
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add %o1, 2, %o1
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srl %g7, 16, %g3
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addx %g0, %g3, %g4
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sll %g7, 16, %g7
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sll %g4, 16, %g3
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srl %g7, 16, %g7
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andcc %o0, 0x4, %g0
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or %g3, %g7, %g7
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1: be 3f
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andcc %g1, 0xffffff80, %g0
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EX(ld [%o0 + 0x00], %g4)
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sub %g1, 4, %g1
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EX(st %g4, [%o1 + 0x00])
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add %o0, 4, %o0
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addcc %g4, %g7, %g7
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add %o1, 4, %o1
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addx %g0, %g7, %g7
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b 3f
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andcc %g1, 0xffffff80, %g0
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/* Sun, you just can't beat me, you just can't. Stop trying,
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* give up. I'm serious, I am going to kick the living shit
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* out of you, game over, lights out.
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*/
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.align 8
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.globl __csum_partial_copy_sparc_generic
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EXPORT_SYMBOL(__csum_partial_copy_sparc_generic)
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__csum_partial_copy_sparc_generic:
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/* %o0=src, %o1=dest, %g1=len, %g7=sum */
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xor %o0, %o1, %o4 ! get changing bits
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andcc %o4, 3, %g0 ! check for mismatched alignment
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bne ccslow ! better this than unaligned/fixups
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andcc %o0, 7, %g0 ! need to align things?
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bne cc_dword_align ! yes, we check for short lengths there
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andcc %g1, 0xffffff80, %g0 ! can we use unrolled loop?
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3: be 3f ! nope, less than one loop remains
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andcc %o1, 4, %g0 ! dest aligned on 4 or 8 byte boundary?
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be ccdbl + 4 ! 8 byte aligned, kick ass
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5: CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x00,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x20,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x40,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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CSUMCOPY_BIGCHUNK(%o0,%o1,%g7,0x60,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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sub %g1, 128, %g1 ! detract from length
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addx %g0, %g7, %g7 ! add in last carry bit
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andcc %g1, 0xffffff80, %g0 ! more to csum?
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add %o0, 128, %o0 ! advance src ptr
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bne 5b ! we did not go negative, continue looping
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add %o1, 128, %o1 ! advance dest ptr
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3: andcc %g1, 0x70, %o2 ! can use table?
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ccmerge:be ccte ! nope, go and check for end cruft
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andcc %g1, 0xf, %o3 ! get low bits of length (clears carry btw)
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srl %o2, 1, %o4 ! begin negative offset computation
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sethi %hi(12f), %o5 ! set up table ptr end
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add %o0, %o2, %o0 ! advance src ptr
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sub %o5, %o4, %o5 ! continue table calculation
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sll %o2, 1, %g2 ! constant multiplies are fun...
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sub %o5, %g2, %o5 ! some more adjustments
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jmp %o5 + %lo(12f) ! jump into it, duff style, wheee...
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add %o1, %o2, %o1 ! advance dest ptr (carry is clear btw)
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cctbl: CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x68,%g2,%g3,%g4,%g5)
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CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x58,%g2,%g3,%g4,%g5)
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CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x48,%g2,%g3,%g4,%g5)
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CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x38,%g2,%g3,%g4,%g5)
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CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x28,%g2,%g3,%g4,%g5)
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CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x18,%g2,%g3,%g4,%g5)
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CSUMCOPY_LASTCHUNK(%o0,%o1,%g7,0x08,%g2,%g3,%g4,%g5)
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12: addx %g0, %g7, %g7
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andcc %o3, 0xf, %g0 ! check for low bits set
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ccte: bne cc_end_cruft ! something left, handle it out of band
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andcc %o3, 8, %g0 ! begin checks for that code
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retl ! return
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mov %g7, %o0 ! give em the computed checksum
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ccdbl: CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x00,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x20,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x40,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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|
CSUMCOPY_BIGCHUNK_ALIGNED(%o0,%o1,%g7,0x60,%o4,%o5,%g2,%g3,%g4,%g5,%o2,%o3)
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|
sub %g1, 128, %g1 ! detract from length
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|
addx %g0, %g7, %g7 ! add in last carry bit
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|
andcc %g1, 0xffffff80, %g0 ! more to csum?
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|
add %o0, 128, %o0 ! advance src ptr
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|
bne ccdbl ! we did not go negative, continue looping
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|
add %o1, 128, %o1 ! advance dest ptr
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b ccmerge ! finish it off, above
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|
andcc %g1, 0x70, %o2 ! can use table? (clears carry btw)
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|
|
|
ccslow: cmp %g1, 0
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|
mov 0, %g5
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|
bleu 4f
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|
andcc %o0, 1, %o5
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|
be,a 1f
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|
srl %g1, 1, %g4
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|
sub %g1, 1, %g1
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|
EX(ldub [%o0], %g5)
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|
add %o0, 1, %o0
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|
EX(stb %g5, [%o1])
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|
srl %g1, 1, %g4
|
|
add %o1, 1, %o1
|
|
1: cmp %g4, 0
|
|
be,a 3f
|
|
andcc %g1, 1, %g0
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|
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:
|
|
ret
|
|
clr %o0
|