diff options
Diffstat (limited to 'arch/powerpc/lib/copy_32.S')
| -rw-r--r-- | arch/powerpc/lib/copy_32.S | 518 |
1 files changed, 518 insertions, 0 deletions
diff --git a/arch/powerpc/lib/copy_32.S b/arch/powerpc/lib/copy_32.S new file mode 100644 index 000000000..a3bcf4786 --- /dev/null +++ b/arch/powerpc/lib/copy_32.S @@ -0,0 +1,518 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Memory copy functions for 32-bit PowerPC. + * + * Copyright (C) 1996-2005 Paul Mackerras. + */ +#include <asm/processor.h> +#include <asm/cache.h> +#include <asm/errno.h> +#include <asm/ppc_asm.h> +#include <asm/export.h> +#include <asm/code-patching-asm.h> +#include <asm/kasan.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; \ + EX_TABLE(8 ## n ## 0b,9 ## n ## 0b); \ + EX_TABLE(8 ## n ## 1b,9 ## n ## 0b); \ + EX_TABLE(8 ## n ## 2b,9 ## n ## 0b); \ + EX_TABLE(8 ## n ## 3b,9 ## n ## 0b); \ + EX_TABLE(8 ## n ## 4b,9 ## n ## 1b); \ + EX_TABLE(8 ## n ## 5b,9 ## n ## 1b); \ + EX_TABLE(8 ## n ## 6b,9 ## n ## 1b); \ + EX_TABLE(8 ## n ## 7b,9 ## n ## 1b) + + .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) + +#ifndef CONFIG_KASAN +_GLOBAL(memset16) + rlwinm. r0 ,r5, 31, 1, 31 + addi r6, r3, -4 + beq- 2f + rlwimi r4 ,r4 ,16 ,0 ,15 + mtctr r0 +1: stwu r4, 4(r6) + bdnz 1b +2: andi. r0, r5, 1 + beqlr + sth r4, 4(r6) + blr +EXPORT_SYMBOL(memset16) +#endif + +/* + * Use dcbz on the complete cache lines in the destination + * to set them to zero. This requires that the destination + * area is cacheable. -- paulus + * + * During early init, cache might not be active yet, so dcbz cannot be used. + * We therefore skip the optimised bloc that uses dcbz. This jump is + * replaced by a nop once cache is active. This is done in machine_init() + */ +_GLOBAL_KASAN(memset) + cmplwi 0,r5,4 + blt 7f + + rlwimi r4,r4,8,16,23 + rlwimi r4,r4,16,0,15 + + stw r4,0(r3) + beqlr + andi. r0,r3,3 + add r5,r0,r5 + subf r6,r0,r3 + cmplwi 0,r4,0 + /* + * Skip optimised bloc until cache is enabled. Will be replaced + * by 'bne' during boot to use normal procedure if r4 is not zero + */ +5: b 2f + patch_site 5b, patch__memset_nocache + + clrlwi r7,r6,32-LG_CACHELINE_BYTES + add r8,r7,r5 + srwi r9,r8,LG_CACHELINE_BYTES + addic. r9,r9,-1 /* total number of complete cachelines */ + ble 2f + xori r0,r7,CACHELINE_MASK & ~3 + srwi. r0,r0,2 + beq 3f + mtctr r0 +4: stwu r4,4(r6) + bdnz 4b +3: mtctr r9 + li r7,4 +10: dcbz r7,r6 + addi r6,r6,CACHELINE_BYTES + bdnz 10b + clrlwi r5,r8,32-LG_CACHELINE_BYTES + addi r5,r5,4 + +2: srwi r0,r5,2 + mtctr r0 + bdz 6f +1: stwu r4,4(r6) + bdnz 1b +6: andi. r5,r5,3 + beqlr + mtctr r5 + addi r6,r6,3 +8: stbu r4,1(r6) + bdnz 8b + blr + +7: cmpwi 0,r5,0 + beqlr + mtctr r5 + addi r6,r3,-1 +9: stbu r4,1(r6) + bdnz 9b + blr +EXPORT_SYMBOL(memset) +EXPORT_SYMBOL_KASAN(memset) + +/* + * This version uses dcbz on the complete cache lines in the + * destination area to reduce memory traffic. This requires that + * the destination area is cacheable. + * We only use this version if the source and dest don't overlap. + * -- paulus. + * + * During early init, cache might not be active yet, so dcbz cannot be used. + * We therefore jump to generic_memcpy which doesn't use dcbz. This jump is + * replaced by a nop once cache is active. This is done in machine_init() + */ +_GLOBAL_KASAN(memmove) + cmplw 0,r3,r4 + bgt backwards_memcpy + /* fall through */ + +_GLOBAL_KASAN(memcpy) +1: b generic_memcpy + patch_site 1b, patch__memcpy_nocache + + add r7,r3,r5 /* test if the src & dst overlap */ + add r8,r4,r5 + cmplw 0,r4,r7 + cmplw 1,r3,r8 + crand 0,0,4 /* cr0.lt &= cr1.lt */ + blt generic_memcpy /* if regions overlap */ + + 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 */ + subf r5,r0,r5 + mtctr r8 + beq+ 61f +70: lbz r9,4(r4) /* do some bytes */ + addi r4,r4,1 + addi r6,r6,1 + stb r9,3(r6) + bdnz 70b +61: srwi. r0,r0,2 + mtctr r0 + beq 58f +72: lwzu r9,4(r4) /* do some words */ + stwu r9,4(r6) + bdnz 72b + +58: srwi. r0,r5,LG_CACHELINE_BYTES /* # complete cachelines */ + clrlwi r5,r5,32-LG_CACHELINE_BYTES + li r11,4 + mtctr r0 + beq 63f +53: + dcbz r11,r6 + COPY_16_BYTES +#if L1_CACHE_BYTES >= 32 + COPY_16_BYTES +#if L1_CACHE_BYTES >= 64 + COPY_16_BYTES + COPY_16_BYTES +#if L1_CACHE_BYTES >= 128 + COPY_16_BYTES + COPY_16_BYTES + COPY_16_BYTES + COPY_16_BYTES +#endif +#endif +#endif + bdnz 53b + +63: srwi. r0,r5,2 + mtctr r0 + beq 64f +30: lwzu r0,4(r4) + stwu r0,4(r6) + bdnz 30b + +64: andi. r0,r5,3 + mtctr r0 + beq+ 65f + addi r4,r4,3 + addi r6,r6,3 +40: lbzu r0,1(r4) + stbu r0,1(r6) + bdnz 40b +65: blr +EXPORT_SYMBOL(memcpy) +EXPORT_SYMBOL(memmove) +EXPORT_SYMBOL_KASAN(memcpy) +EXPORT_SYMBOL_KASAN(memmove) + +generic_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 + + EX_TABLE(70b,100f) + EX_TABLE(71b,101f) + EX_TABLE(72b,102f) + EX_TABLE(73b,103f) + +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 + EX_TABLE(54b,105f) +/* 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 +120: blr + + EX_TABLE(30b,108b) + EX_TABLE(31b,109b) + EX_TABLE(40b,110b) + EX_TABLE(41b,111b) + EX_TABLE(130b,132b) + EX_TABLE(131b,120b) + +EXPORT_SYMBOL(__copy_tofrom_user) |