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-rw-r--r--arch/powerpc/lib/checksum_32.S309
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diff --git a/arch/powerpc/lib/checksum_32.S b/arch/powerpc/lib/checksum_32.S
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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * This file contains assembly-language implementations
+ * of IP-style 1's complement checksum routines.
+ *
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Severely hacked about by Paul Mackerras (paulus@cs.anu.edu.au).
+ */
+
+#include <linux/export.h>
+#include <linux/sys.h>
+#include <asm/processor.h>
+#include <asm/cache.h>
+#include <asm/errno.h>
+#include <asm/ppc_asm.h>
+
+ .text
+
+/*
+ * computes the checksum of a memory block at buff, length len,
+ * and adds in "sum" (32-bit)
+ *
+ * __csum_partial(buff, len, sum)
+ */
+_GLOBAL(__csum_partial)
+ subi r3,r3,4
+ srawi. r6,r4,2 /* Divide len by 4 and also clear carry */
+ beq 3f /* if we're doing < 4 bytes */
+ andi. r0,r3,2 /* Align buffer to longword boundary */
+ beq+ 1f
+ lhz r0,4(r3) /* do 2 bytes to get aligned */
+ subi r4,r4,2
+ addi r3,r3,2
+ srwi. r6,r4,2 /* # words to do */
+ adde r5,r5,r0
+ beq 3f
+1: andi. r6,r6,3 /* Prepare to handle words 4 by 4 */
+ beq 21f
+ mtctr r6
+2: lwzu r0,4(r3)
+ adde r5,r5,r0
+ bdnz 2b
+21: srwi. r6,r4,4 /* # blocks of 4 words to do */
+ beq 3f
+ lwz r0,4(r3)
+ mtctr r6
+ lwz r6,8(r3)
+ adde r5,r5,r0
+ lwz r7,12(r3)
+ adde r5,r5,r6
+ lwzu r8,16(r3)
+ adde r5,r5,r7
+ bdz 23f
+22: lwz r0,4(r3)
+ adde r5,r5,r8
+ lwz r6,8(r3)
+ adde r5,r5,r0
+ lwz r7,12(r3)
+ adde r5,r5,r6
+ lwzu r8,16(r3)
+ adde r5,r5,r7
+ bdnz 22b
+23: adde r5,r5,r8
+3: andi. r0,r4,2
+ beq+ 4f
+ lhz r0,4(r3)
+ addi r3,r3,2
+ adde r5,r5,r0
+4: andi. r0,r4,1
+ beq+ 5f
+ lbz r0,4(r3)
+ slwi r0,r0,8 /* Upper byte of word */
+ adde r5,r5,r0
+5: addze r3,r5 /* add in final carry */
+ blr
+EXPORT_SYMBOL(__csum_partial)
+
+/*
+ * Computes the checksum of a memory block at src, length len,
+ * and adds in 0xffffffff, while copying the block to dst.
+ * If an access exception occurs it returns zero.
+ *
+ * csum_partial_copy_generic(src, dst, len)
+ */
+#define CSUM_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); \
+ adde r12,r12,r7; \
+8 ## n ## 5: \
+ stw r8,8(r6); \
+ adde r12,r12,r8; \
+8 ## n ## 6: \
+ stw r9,12(r6); \
+ adde r12,r12,r9; \
+8 ## n ## 7: \
+ stwu r10,16(r6); \
+ adde r12,r12,r10
+
+#define CSUM_COPY_16_BYTES_EXCODE(n) \
+ EX_TABLE(8 ## n ## 0b, fault); \
+ EX_TABLE(8 ## n ## 1b, fault); \
+ EX_TABLE(8 ## n ## 2b, fault); \
+ EX_TABLE(8 ## n ## 3b, fault); \
+ EX_TABLE(8 ## n ## 4b, fault); \
+ EX_TABLE(8 ## n ## 5b, fault); \
+ EX_TABLE(8 ## n ## 6b, fault); \
+ EX_TABLE(8 ## n ## 7b, fault);
+
+ .text
+
+CACHELINE_BYTES = L1_CACHE_BYTES
+LG_CACHELINE_BYTES = L1_CACHE_SHIFT
+CACHELINE_MASK = (L1_CACHE_BYTES-1)
+
+_GLOBAL(csum_partial_copy_generic)
+ li r12,-1
+ addic r0,r0,0 /* clear carry */
+ addi r6,r4,-4
+ neg r0,r4
+ addi r4,r3,-4
+ andi. r0,r0,CACHELINE_MASK /* # bytes to start of cache line */
+ crset 4*cr7+eq
+ beq 58f
+
+ cmplw 0,r5,r0 /* is this more than total to do? */
+ blt 63f /* if not much to do */
+ rlwinm r7,r6,3,0x8
+ rlwnm r12,r12,r7,0,31 /* odd destination address: rotate one byte */
+ cmplwi cr7,r7,0 /* is destination address even ? */
+ andi. r8,r0,3 /* get it word-aligned first */
+ mtctr r8
+ beq+ 61f
+ li r3,0
+70: lbz r9,4(r4) /* do some bytes */
+ addi r4,r4,1
+ slwi r3,r3,8
+ rlwimi r3,r9,0,24,31
+71: stb r9,4(r6)
+ addi r6,r6,1
+ bdnz 70b
+ adde r12,r12,r3
+61: subf r5,r0,r5
+ srwi. r0,r0,2
+ mtctr r0
+ beq 58f
+72: lwzu r9,4(r4) /* do some words */
+ adde r12,r12,r9
+73: 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
+ 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
+/* the main body of the cacheline loop */
+ CSUM_COPY_16_BYTES_WITHEX(0)
+#if L1_CACHE_BYTES >= 32
+ CSUM_COPY_16_BYTES_WITHEX(1)
+#if L1_CACHE_BYTES >= 64
+ CSUM_COPY_16_BYTES_WITHEX(2)
+ CSUM_COPY_16_BYTES_WITHEX(3)
+#if L1_CACHE_BYTES >= 128
+ CSUM_COPY_16_BYTES_WITHEX(4)
+ CSUM_COPY_16_BYTES_WITHEX(5)
+ CSUM_COPY_16_BYTES_WITHEX(6)
+ CSUM_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)
+ adde r12,r12,r0
+31: stwu r0,4(r6)
+ bdnz 30b
+
+64: andi. r0,r5,2
+ beq+ 65f
+40: lhz r0,4(r4)
+ addi r4,r4,2
+41: sth r0,4(r6)
+ adde r12,r12,r0
+ addi r6,r6,2
+65: andi. r0,r5,1
+ beq+ 66f
+50: lbz r0,4(r4)
+51: stb r0,4(r6)
+ slwi r0,r0,8
+ adde r12,r12,r0
+66: addze r3,r12
+ beqlr+ cr7
+ rlwinm r3,r3,8,0,31 /* odd destination address: rotate one byte */
+ blr
+
+fault:
+ li r3,0
+ blr
+
+ EX_TABLE(70b, fault);
+ EX_TABLE(71b, fault);
+ EX_TABLE(72b, fault);
+ EX_TABLE(73b, fault);
+ EX_TABLE(54b, fault);
+
+/*
+ * this stuff handles faults in the cacheline loop and branches to either
+ * fault (if in read part) or fault (if in write part)
+ */
+ CSUM_COPY_16_BYTES_EXCODE(0)
+#if L1_CACHE_BYTES >= 32
+ CSUM_COPY_16_BYTES_EXCODE(1)
+#if L1_CACHE_BYTES >= 64
+ CSUM_COPY_16_BYTES_EXCODE(2)
+ CSUM_COPY_16_BYTES_EXCODE(3)
+#if L1_CACHE_BYTES >= 128
+ CSUM_COPY_16_BYTES_EXCODE(4)
+ CSUM_COPY_16_BYTES_EXCODE(5)
+ CSUM_COPY_16_BYTES_EXCODE(6)
+ CSUM_COPY_16_BYTES_EXCODE(7)
+#endif
+#endif
+#endif
+
+ EX_TABLE(30b, fault);
+ EX_TABLE(31b, fault);
+ EX_TABLE(40b, fault);
+ EX_TABLE(41b, fault);
+ EX_TABLE(50b, fault);
+ EX_TABLE(51b, fault);
+
+EXPORT_SYMBOL(csum_partial_copy_generic)
+
+/*
+ * __sum16 csum_ipv6_magic(const struct in6_addr *saddr,
+ * const struct in6_addr *daddr,
+ * __u32 len, __u8 proto, __wsum sum)
+ */
+
+_GLOBAL(csum_ipv6_magic)
+ lwz r8, 0(r3)
+ lwz r9, 4(r3)
+ addc r0, r7, r8
+ lwz r10, 8(r3)
+ adde r0, r0, r9
+ lwz r11, 12(r3)
+ adde r0, r0, r10
+ lwz r8, 0(r4)
+ adde r0, r0, r11
+ lwz r9, 4(r4)
+ adde r0, r0, r8
+ lwz r10, 8(r4)
+ adde r0, r0, r9
+ lwz r11, 12(r4)
+ adde r0, r0, r10
+ add r5, r5, r6 /* assumption: len + proto doesn't carry */
+ adde r0, r0, r11
+ adde r0, r0, r5
+ addze r0, r0
+ rotlwi r3, r0, 16
+ add r3, r0, r3
+ not r3, r3
+ rlwinm r3, r3, 16, 16, 31
+ blr
+EXPORT_SYMBOL(csum_ipv6_magic)