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-rw-r--r--arch/powerpc/cpu/mpc5xxx/Makefile5
-rw-r--r--arch/powerpc/cpu/mpc5xxx/memcpy_mpc5200.c71
2 files changed, 76 insertions, 0 deletions
diff --git a/arch/powerpc/cpu/mpc5xxx/Makefile b/arch/powerpc/cpu/mpc5xxx/Makefile
index 0ee061155..4ab2b7be7 100644
--- a/arch/powerpc/cpu/mpc5xxx/Makefile
+++ b/arch/powerpc/cpu/mpc5xxx/Makefile
@@ -30,6 +30,11 @@ SOBJS = io.o firmware_sc_task_bestcomm.impl.o
COBJS = i2c.o traps.o cpu.o cpu_init.o ide.o interrupts.o \
loadtask.o pci_mpc5200.o serial.o speed.o usb_ohci.o usb.o
+# Workaround for local bus unaligned access problem on MPC5200
+#ifdef CONFIG_MPC5200
+COBJS += memcpy_mpc5200.o
+#endif
+
SRCS := $(START:.o=.S) $(SOBJS:.o=.S) $(COBJS:.o=.c)
OBJS := $(addprefix $(obj),$(SOBJS) $(COBJS))
START := $(addprefix $(obj),$(START))
diff --git a/arch/powerpc/cpu/mpc5xxx/memcpy_mpc5200.c b/arch/powerpc/cpu/mpc5xxx/memcpy_mpc5200.c
new file mode 100644
index 000000000..09503548a
--- /dev/null
+++ b/arch/powerpc/cpu/mpc5xxx/memcpy_mpc5200.c
@@ -0,0 +1,71 @@
+/*
+ * (C) Copyright 2010
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+/*
+ * 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;
+}