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Diffstat (limited to 'kernel/arch/powerpc/lib/copy_32.S')
| -rw-r--r-- | kernel/arch/powerpc/lib/copy_32.S | 391 |
1 files changed, 391 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/lib/copy_32.S b/kernel/arch/powerpc/lib/copy_32.S new file mode 100644 index 000000000..6813f80d1 --- /dev/null +++ b/kernel/arch/powerpc/lib/copy_32.S @@ -0,0 +1,391 @@ +/* + * Memory copy functions for 32-bit PowerPC. + * + * Copyright (C) 1996-2005 Paul Mackerras. + * + * 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 <asm/processor.h> +#include <asm/cache.h> +#include <asm/errno.h> +#include <asm/ppc_asm.h> + +#define COPY_16_BYTES \ + lwz r7,4(r4); \ + lwz r8,8(r4); \ + lwz r9,12(r4); \ + lwzu r10,16(r4); \ + stw r7,4(r6); \ + stw r8,8(r6); \ + stw r9,12(r6); \ + stwu r10,16(r6) + +#define COPY_16_BYTES_WITHEX(n) \ +8 ## n ## 0: \ + lwz r7,4(r4); \ +8 ## n ## 1: \ + lwz r8,8(r4); \ +8 ## n ## 2: \ + lwz r9,12(r4); \ +8 ## n ## 3: \ + lwzu r10,16(r4); \ +8 ## n ## 4: \ + stw r7,4(r6); \ +8 ## n ## 5: \ + stw r8,8(r6); \ +8 ## n ## 6: \ + stw r9,12(r6); \ +8 ## n ## 7: \ + stwu r10,16(r6) + +#define COPY_16_BYTES_EXCODE(n) \ +9 ## n ## 0: \ + addi r5,r5,-(16 * n); \ + b 104f; \ +9 ## n ## 1: \ + addi r5,r5,-(16 * n); \ + b 105f; \ +.section __ex_table,"a"; \ + .align 2; \ + .long 8 ## n ## 0b,9 ## n ## 0b; \ + .long 8 ## n ## 1b,9 ## n ## 0b; \ + .long 8 ## n ## 2b,9 ## n ## 0b; \ + .long 8 ## n ## 3b,9 ## n ## 0b; \ + .long 8 ## n ## 4b,9 ## n ## 1b; \ + .long 8 ## n ## 5b,9 ## n ## 1b; \ + .long 8 ## n ## 6b,9 ## n ## 1b; \ + .long 8 ## n ## 7b,9 ## n ## 1b; \ + .text + + .text + .stabs "arch/powerpc/lib/",N_SO,0,0,0f + .stabs "copy_32.S",N_SO,0,0,0f +0: + +CACHELINE_BYTES = L1_CACHE_BYTES +LG_CACHELINE_BYTES = L1_CACHE_SHIFT +CACHELINE_MASK = (L1_CACHE_BYTES-1) + +_GLOBAL(memset) + rlwimi r4,r4,8,16,23 + rlwimi r4,r4,16,0,15 + addi r6,r3,-4 + cmplwi 0,r5,4 + blt 7f + stwu r4,4(r6) + beqlr + andi. r0,r6,3 + add r5,r0,r5 + subf r6,r0,r6 + srwi r0,r5,2 + mtctr r0 + bdz 6f +1: stwu r4,4(r6) + bdnz 1b +6: andi. r5,r5,3 +7: cmpwi 0,r5,0 + beqlr + mtctr r5 + addi r6,r6,3 +8: stbu r4,1(r6) + bdnz 8b + blr + +_GLOBAL(memmove) + cmplw 0,r3,r4 + bgt backwards_memcpy + /* fall through */ + +_GLOBAL(memcpy) + srwi. r7,r5,3 + addi r6,r3,-4 + addi r4,r4,-4 + beq 2f /* if less than 8 bytes to do */ + andi. r0,r6,3 /* get dest word aligned */ + mtctr r7 + bne 5f +1: lwz r7,4(r4) + lwzu r8,8(r4) + stw r7,4(r6) + stwu r8,8(r6) + bdnz 1b + andi. r5,r5,7 +2: cmplwi 0,r5,4 + blt 3f + lwzu r0,4(r4) + addi r5,r5,-4 + stwu r0,4(r6) +3: cmpwi 0,r5,0 + beqlr + mtctr r5 + addi r4,r4,3 + addi r6,r6,3 +4: lbzu r0,1(r4) + stbu r0,1(r6) + bdnz 4b + blr +5: subfic r0,r0,4 + mtctr r0 +6: lbz r7,4(r4) + addi r4,r4,1 + stb r7,4(r6) + addi r6,r6,1 + bdnz 6b + subf r5,r0,r5 + rlwinm. r7,r5,32-3,3,31 + beq 2b + mtctr r7 + b 1b + +_GLOBAL(backwards_memcpy) + rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */ + add r6,r3,r5 + add r4,r4,r5 + beq 2f + andi. r0,r6,3 + mtctr r7 + bne 5f +1: lwz r7,-4(r4) + lwzu r8,-8(r4) + stw r7,-4(r6) + stwu r8,-8(r6) + bdnz 1b + andi. r5,r5,7 +2: cmplwi 0,r5,4 + blt 3f + lwzu r0,-4(r4) + subi r5,r5,4 + stwu r0,-4(r6) +3: cmpwi 0,r5,0 + beqlr + mtctr r5 +4: lbzu r0,-1(r4) + stbu r0,-1(r6) + bdnz 4b + blr +5: mtctr r0 +6: lbzu r7,-1(r4) + stbu r7,-1(r6) + bdnz 6b + subf r5,r0,r5 + rlwinm. r7,r5,32-3,3,31 + beq 2b + mtctr r7 + b 1b + +_GLOBAL(__copy_tofrom_user) + addi r4,r4,-4 + addi r6,r3,-4 + neg r0,r3 + andi. r0,r0,CACHELINE_MASK /* # bytes to start of cache line */ + beq 58f + + cmplw 0,r5,r0 /* is this more than total to do? */ + blt 63f /* if not much to do */ + andi. r8,r0,3 /* get it word-aligned first */ + mtctr r8 + beq+ 61f +70: lbz r9,4(r4) /* do some bytes */ +71: stb r9,4(r6) + addi r4,r4,1 + addi r6,r6,1 + bdnz 70b +61: subf r5,r0,r5 + srwi. r0,r0,2 + mtctr r0 + beq 58f +72: lwzu r9,4(r4) /* do some words */ +73: stwu r9,4(r6) + bdnz 72b + + .section __ex_table,"a" + .align 2 + .long 70b,100f + .long 71b,101f + .long 72b,102f + .long 73b,103f + .text + +58: srwi. r0,r5,LG_CACHELINE_BYTES /* # complete cachelines */ + clrlwi r5,r5,32-LG_CACHELINE_BYTES + li r11,4 + beq 63f + + /* Here we decide how far ahead to prefetch the source */ + li r3,4 + cmpwi r0,1 + li r7,0 + ble 114f + li r7,1 +#if MAX_COPY_PREFETCH > 1 + /* Heuristically, for large transfers we prefetch + MAX_COPY_PREFETCH cachelines ahead. For small transfers + we prefetch 1 cacheline ahead. */ + cmpwi r0,MAX_COPY_PREFETCH + ble 112f + li r7,MAX_COPY_PREFETCH +112: mtctr r7 +111: dcbt r3,r4 + addi r3,r3,CACHELINE_BYTES + bdnz 111b +#else + dcbt r3,r4 + addi r3,r3,CACHELINE_BYTES +#endif /* MAX_COPY_PREFETCH > 1 */ + +114: subf r8,r7,r0 + mr r0,r7 + mtctr r8 + +53: dcbt r3,r4 +54: dcbz r11,r6 + .section __ex_table,"a" + .align 2 + .long 54b,105f + .text +/* the main body of the cacheline loop */ + COPY_16_BYTES_WITHEX(0) +#if L1_CACHE_BYTES >= 32 + COPY_16_BYTES_WITHEX(1) +#if L1_CACHE_BYTES >= 64 + COPY_16_BYTES_WITHEX(2) + COPY_16_BYTES_WITHEX(3) +#if L1_CACHE_BYTES >= 128 + COPY_16_BYTES_WITHEX(4) + COPY_16_BYTES_WITHEX(5) + COPY_16_BYTES_WITHEX(6) + COPY_16_BYTES_WITHEX(7) +#endif +#endif +#endif + bdnz 53b + cmpwi r0,0 + li r3,4 + li r7,0 + bne 114b + +63: srwi. r0,r5,2 + mtctr r0 + beq 64f +30: lwzu r0,4(r4) +31: stwu r0,4(r6) + bdnz 30b + +64: andi. r0,r5,3 + mtctr r0 + beq+ 65f +40: lbz r0,4(r4) +41: stb r0,4(r6) + addi r4,r4,1 + addi r6,r6,1 + bdnz 40b +65: li r3,0 + blr + +/* read fault, initial single-byte copy */ +100: li r9,0 + b 90f +/* write fault, initial single-byte copy */ +101: li r9,1 +90: subf r5,r8,r5 + li r3,0 + b 99f +/* read fault, initial word copy */ +102: li r9,0 + b 91f +/* write fault, initial word copy */ +103: li r9,1 +91: li r3,2 + b 99f + +/* + * this stuff handles faults in the cacheline loop and branches to either + * 104f (if in read part) or 105f (if in write part), after updating r5 + */ + COPY_16_BYTES_EXCODE(0) +#if L1_CACHE_BYTES >= 32 + COPY_16_BYTES_EXCODE(1) +#if L1_CACHE_BYTES >= 64 + COPY_16_BYTES_EXCODE(2) + COPY_16_BYTES_EXCODE(3) +#if L1_CACHE_BYTES >= 128 + COPY_16_BYTES_EXCODE(4) + COPY_16_BYTES_EXCODE(5) + COPY_16_BYTES_EXCODE(6) + COPY_16_BYTES_EXCODE(7) +#endif +#endif +#endif + +/* read fault in cacheline loop */ +104: li r9,0 + b 92f +/* fault on dcbz (effectively a write fault) */ +/* or write fault in cacheline loop */ +105: li r9,1 +92: li r3,LG_CACHELINE_BYTES + mfctr r8 + add r0,r0,r8 + b 106f +/* read fault in final word loop */ +108: li r9,0 + b 93f +/* write fault in final word loop */ +109: li r9,1 +93: andi. r5,r5,3 + li r3,2 + b 99f +/* read fault in final byte loop */ +110: li r9,0 + b 94f +/* write fault in final byte loop */ +111: li r9,1 +94: li r5,0 + li r3,0 +/* + * At this stage the number of bytes not copied is + * r5 + (ctr << r3), and r9 is 0 for read or 1 for write. + */ +99: mfctr r0 +106: slw r3,r0,r3 + add. r3,r3,r5 + beq 120f /* shouldn't happen */ + cmpwi 0,r9,0 + bne 120f +/* for a read fault, first try to continue the copy one byte at a time */ + mtctr r3 +130: lbz r0,4(r4) +131: stb r0,4(r6) + addi r4,r4,1 + addi r6,r6,1 + bdnz 130b +/* then clear out the destination: r3 bytes starting at 4(r6) */ +132: mfctr r3 + srwi. r0,r3,2 + li r9,0 + mtctr r0 + beq 113f +112: stwu r9,4(r6) + bdnz 112b +113: andi. r0,r3,3 + mtctr r0 + beq 120f +114: stb r9,4(r6) + addi r6,r6,1 + bdnz 114b +120: blr + + .section __ex_table,"a" + .align 2 + .long 30b,108b + .long 31b,109b + .long 40b,110b + .long 41b,111b + .long 130b,132b + .long 131b,120b + .long 112b,120b + .long 114b,120b + .text |