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/*
* (C) Copyright 2010
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* This is a workaround for issues on the MPC5200, where unaligned
* 32-bit-accesses to the local bus will deliver corrupted data. This
* happens for example when trying to use memcpy() from an odd NOR
* flash address; the behaviour can be also seen when using "md" on an
* odd NOR flash address (but there it is not a bug in U-Boot, which
* only shows the behaviour of this processor).
*
* For memcpy(), we test if either the source or the target address
* are not 32 bit aligned, and - if so - if the source address is in
* NOR flash: in this case we perform a byte-wise (slow) then; for
* aligned operations of non-flash areas we use the optimized (fast)
* real __memcpy(). This way we minimize the performance impact of
* this workaround.
*
*/
#include <common.h>
#include <flash.h>
#include <linux/types.h>
void *memcpy(void *trg, const void *src, size_t len)
{
extern void* __memcpy(void *, const void *, size_t);
char *s = (char *)src;
char *t = (char *)trg;
void *dest = (void *)src;
/*
* Check is source address is in flash:
* If not, we use the fast assembler code
*/
if (((((unsigned long)s & 3) == 0) /* source aligned */
&& /* AND */
(((unsigned long)t & 3) == 0)) /* target aligned, */
|| /* or */
(addr2info((ulong)s) == NULL)) { /* source not in flash */
return __memcpy(trg, src, len);
}
/*
* Copying from flash, perform byte by byte copy.
*/
while (len-- > 0)
*t++ = *s++;
return dest;
}
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