1/* 2 * (C) Copyright 2010 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8/* 9 * This is a workaround for issues on the MPC5200, where unaligned 10 * 32-bit-accesses to the local bus will deliver corrupted data. This 11 * happens for example when trying to use memcpy() from an odd NOR 12 * flash address; the behaviour can be also seen when using "md" on an 13 * odd NOR flash address (but there it is not a bug in U-Boot, which 14 * only shows the behaviour of this processor). 15 * 16 * For memcpy(), we test if either the source or the target address 17 * are not 32 bit aligned, and - if so - if the source address is in 18 * NOR flash: in this case we perform a byte-wise (slow) then; for 19 * aligned operations of non-flash areas we use the optimized (fast) 20 * real __memcpy(). This way we minimize the performance impact of 21 * this workaround. 22 * 23 */ 24 25#include <common.h> 26#include <flash.h> 27#include <linux/types.h> 28 29void *memcpy(void *trg, const void *src, size_t len) 30{ 31 extern void* __memcpy(void *, const void *, size_t); 32 char *s = (char *)src; 33 char *t = (char *)trg; 34 void *dest = (void *)src; 35 36 /* 37 * Check is source address is in flash: 38 * If not, we use the fast assembler code 39 */ 40 if (((((unsigned long)s & 3) == 0) /* source aligned */ 41 && /* AND */ 42 (((unsigned long)t & 3) == 0)) /* target aligned, */ 43 || /* or */ 44 (addr2info((ulong)s) == NULL)) { /* source not in flash */ 45 return __memcpy(trg, src, len); 46 } 47 48 /* 49 * Copying from flash, perform byte by byte copy. 50 */ 51 while (len-- > 0) 52 *t++ = *s++; 53 54 return dest; 55} 56