u-boot/arch/powerpc/cpu/mpc5xxx/Makefile
Wolfgang Denk 460c2ce362 MPC5200: workaround data corruption for unaligned local bus accesses
The MPC5200 has a nasty problem that will cause silent data corruption
when performing unaligned 16 or 32 byte accesses when reading from the
local bus - typically this affects reading from flash. The problem can
be easily shown:

=> md fc0c0000 10
fc0c0000: 323e4337 01626f6f 74636d64 3d72756e    2>C7.bootcmd=run
fc0c0010: 206e6574 5f6e6673 00626f6f 7464656c     net_nfs.bootdel
fc0c0020: 61793d35 00626175 64726174 653d3131    ay=5.baudrate=11
fc0c0030: 35323030 00707265 626f6f74 3d656368    5200.preboot=ech
=> md fc0c0001 10
fc0c0001: 65636801 00000074 0000003d 00000020    ech....t...=...
fc0c0011: 0000005f 00000000 00000074 00000061    ..._.......t...a
fc0c0021: 00000000 00000064 00000065 00000035    .......d...e...5
fc0c0031: 00000000 00000062 0000003d 0000006f    .......b...=...o
=> md.w fc0c0001 10
fc0c0001: 0000 3701 0000 6f74 0000 643d 0000 6e20    ..7...ot..d=..n
fc0c0011: 0000 745f 0000 7300 0000 6f74 0000 6c61    ..t_..s...ot..la

This commit implements a workaround at least for the most blatant
problem: using memcpy() from NOR flash. We rename the assembler
routine into __memcpy() and provide a wrapper, which will use a
byte-wise copy loop for unaligned source or target addresses when
reading from NOR flash, and branch to the optimized __memcpy()
in all other cases, thus minimizing the performance impact.

Tested on lite5200b and TQM5200S.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Detlev Zundel <dzu@denx.de>
2010-06-23 02:09:20 +02:00

54 lines
1.6 KiB
Makefile

#
# (C) Copyright 2003-2006
# 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
#
include $(TOPDIR)/config.mk
LIB = $(obj)lib$(CPU).a
START = start.o
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))
all: $(obj).depend $(START) $(LIB)
$(LIB): $(OBJS)
$(AR) $(ARFLAGS) $@ $(OBJS)
#########################################################################
# defines $(obj).depend target
include $(SRCTREE)/rules.mk
sinclude $(obj).depend
#########################################################################