mirror of
https://github.com/torvalds/linux.git
synced 2024-12-14 23:25:54 +00:00
1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
173 lines
3.7 KiB
ArmAsm
173 lines
3.7 KiB
ArmAsm
/* checksum.S: Sparc V9 optimized checksum code.
|
|
*
|
|
* Copyright(C) 1995 Linus Torvalds
|
|
* Copyright(C) 1995 Miguel de Icaza
|
|
* Copyright(C) 1996, 2000 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
|
|
*/
|
|
|
|
.text
|
|
|
|
csum_partial_fix_alignment:
|
|
/* We checked for zero length already, so there must be
|
|
* at least one byte.
|
|
*/
|
|
be,pt %icc, 1f
|
|
nop
|
|
ldub [%o0 + 0x00], %o4
|
|
add %o0, 1, %o0
|
|
sub %o1, 1, %o1
|
|
1: andcc %o0, 0x2, %g0
|
|
be,pn %icc, csum_partial_post_align
|
|
cmp %o1, 2
|
|
blu,pn %icc, csum_partial_end_cruft
|
|
nop
|
|
lduh [%o0 + 0x00], %o5
|
|
add %o0, 2, %o0
|
|
sub %o1, 2, %o1
|
|
ba,pt %xcc, csum_partial_post_align
|
|
add %o5, %o4, %o4
|
|
|
|
.align 32
|
|
.globl csum_partial
|
|
csum_partial: /* %o0=buff, %o1=len, %o2=sum */
|
|
prefetch [%o0 + 0x000], #n_reads
|
|
clr %o4
|
|
prefetch [%o0 + 0x040], #n_reads
|
|
brz,pn %o1, csum_partial_finish
|
|
andcc %o0, 0x3, %g0
|
|
|
|
/* We "remember" whether the lowest bit in the address
|
|
* was set in %g7. Because if it is, we have to swap
|
|
* upper and lower 8 bit fields of the sum we calculate.
|
|
*/
|
|
bne,pn %icc, csum_partial_fix_alignment
|
|
andcc %o0, 0x1, %g7
|
|
|
|
csum_partial_post_align:
|
|
prefetch [%o0 + 0x080], #n_reads
|
|
andncc %o1, 0x3f, %o3
|
|
|
|
prefetch [%o0 + 0x0c0], #n_reads
|
|
sub %o1, %o3, %o1
|
|
brz,pn %o3, 2f
|
|
prefetch [%o0 + 0x100], #n_reads
|
|
|
|
/* So that we don't need to use the non-pairing
|
|
* add-with-carry instructions we accumulate 32-bit
|
|
* values into a 64-bit register. At the end of the
|
|
* loop we fold it down to 32-bits and so on.
|
|
*/
|
|
prefetch [%o0 + 0x140], #n_reads
|
|
1: lduw [%o0 + 0x00], %o5
|
|
lduw [%o0 + 0x04], %g1
|
|
lduw [%o0 + 0x08], %g2
|
|
add %o4, %o5, %o4
|
|
lduw [%o0 + 0x0c], %g3
|
|
add %o4, %g1, %o4
|
|
lduw [%o0 + 0x10], %o5
|
|
add %o4, %g2, %o4
|
|
lduw [%o0 + 0x14], %g1
|
|
add %o4, %g3, %o4
|
|
lduw [%o0 + 0x18], %g2
|
|
add %o4, %o5, %o4
|
|
lduw [%o0 + 0x1c], %g3
|
|
add %o4, %g1, %o4
|
|
lduw [%o0 + 0x20], %o5
|
|
add %o4, %g2, %o4
|
|
lduw [%o0 + 0x24], %g1
|
|
add %o4, %g3, %o4
|
|
lduw [%o0 + 0x28], %g2
|
|
add %o4, %o5, %o4
|
|
lduw [%o0 + 0x2c], %g3
|
|
add %o4, %g1, %o4
|
|
lduw [%o0 + 0x30], %o5
|
|
add %o4, %g2, %o4
|
|
lduw [%o0 + 0x34], %g1
|
|
add %o4, %g3, %o4
|
|
lduw [%o0 + 0x38], %g2
|
|
add %o4, %o5, %o4
|
|
lduw [%o0 + 0x3c], %g3
|
|
add %o4, %g1, %o4
|
|
prefetch [%o0 + 0x180], #n_reads
|
|
add %o4, %g2, %o4
|
|
subcc %o3, 0x40, %o3
|
|
add %o0, 0x40, %o0
|
|
bne,pt %icc, 1b
|
|
add %o4, %g3, %o4
|
|
|
|
2: and %o1, 0x3c, %o3
|
|
brz,pn %o3, 2f
|
|
sub %o1, %o3, %o1
|
|
1: lduw [%o0 + 0x00], %o5
|
|
subcc %o3, 0x4, %o3
|
|
add %o0, 0x4, %o0
|
|
bne,pt %icc, 1b
|
|
add %o4, %o5, %o4
|
|
|
|
2:
|
|
/* fold 64-->32 */
|
|
srlx %o4, 32, %o5
|
|
srl %o4, 0, %o4
|
|
add %o4, %o5, %o4
|
|
srlx %o4, 32, %o5
|
|
srl %o4, 0, %o4
|
|
add %o4, %o5, %o4
|
|
|
|
/* fold 32-->16 */
|
|
sethi %hi(0xffff0000), %g1
|
|
srl %o4, 16, %o5
|
|
andn %o4, %g1, %g2
|
|
add %o5, %g2, %o4
|
|
srl %o4, 16, %o5
|
|
andn %o4, %g1, %g2
|
|
add %o5, %g2, %o4
|
|
|
|
csum_partial_end_cruft:
|
|
/* %o4 has the 16-bit sum we have calculated so-far. */
|
|
cmp %o1, 2
|
|
blu,pt %icc, 1f
|
|
nop
|
|
lduh [%o0 + 0x00], %o5
|
|
sub %o1, 2, %o1
|
|
add %o0, 2, %o0
|
|
add %o4, %o5, %o4
|
|
1: brz,pt %o1, 1f
|
|
nop
|
|
ldub [%o0 + 0x00], %o5
|
|
sub %o1, 1, %o1
|
|
add %o0, 1, %o0
|
|
sllx %o5, 8, %o5
|
|
add %o4, %o5, %o4
|
|
1:
|
|
/* fold 32-->16 */
|
|
sethi %hi(0xffff0000), %g1
|
|
srl %o4, 16, %o5
|
|
andn %o4, %g1, %g2
|
|
add %o5, %g2, %o4
|
|
srl %o4, 16, %o5
|
|
andn %o4, %g1, %g2
|
|
add %o5, %g2, %o4
|
|
|
|
1: brz,pt %g7, 1f
|
|
nop
|
|
|
|
/* We started with an odd byte, byte-swap the result. */
|
|
srl %o4, 8, %o5
|
|
and %o4, 0xff, %g1
|
|
sll %g1, 8, %g1
|
|
or %o5, %g1, %o4
|
|
|
|
1: add %o2, %o4, %o2
|
|
|
|
csum_partial_finish:
|
|
retl
|
|
mov %o2, %o0
|