Using both memory banks for 256Mb DRAM in AT91SAM9G45

Hi,

I have a AT91SAM9G45 kit which has 2 DRAM banks conforming to datasheet
one starting from 0x20000000 marked as EBI Chip Select 1
DDR2-LPDDR-SDRAM and the one that's used by default starting from
0x70000000 marked as DDR2-LPDDR Chip Select.

 I modified U-Boot and initialised the bank at 0x20000000 for kernel
usage by adding:

gd->bd->bi_dram[1].start = 0x20000000;
gd->bd->bi_dram[1].size = 0x8000000;

in dram_init(). After recompiling and flashing U-Boot reports 256Mb, I
also tried some uboot mw/md commands from 0x20000000 and higher and
seems to work so DRAM looks like it's initialised correctly.

The problem appears after booting linux (I'm using a 2.6.27 linux4sam
kernel with -at91 and -exp patches without framebuffer compiled in) and
trying to use more then 128Mb (as a single bank has) the kernel enters
in a recursive OOOPS.
I'm starting the kernel with different bootargs:

1) mem=256Mb
2) Specify and exact map of the memory doesn't help either:
bootargs=mem=256M memmap=exactmap memmap=0x8000000@0x20000000
memmap=0x8000000@0x20000000 ...
3) Tried to map less memory for kernel:
bootargs=mem=200M memmap=exactmap memmap=0x07000000@0x20000000
memmap=0x05000000@0x73000000 


Anyone has any ideea where the problem lies ?


Thanks,
Nicu Pavel

U-Boot messages:

U-Boot 1.3.4 (Sep 4 2009 - 11:59:42)

DRAM: 256 MB
NAND: 256 MiB
DataFlash:AT45DB321
Nb pages: 8192
Page Size: 528
Size= 4325376 bytes
Logical address: 0xC0000000
Area 0: C0000000 to C00041FF (RO) Bootstrap
Area 1: C0004200 to C00083FF Environment
Area 2: C0008400 to C0041FFF (RO) U-Boot
Area 3: C0042000 to C0251FFF Kernel
Area 4: C0252000 to C041FFFF FS
In: serial
Out: serial
Err: serial
Net: macb0
macb0: Starting autonegotiation...
macb0: Autonegotiation timed out (status=0x7849)
macb0: link down (status: 0x7849)
Hit any key to stop autoboot: 0
U-Boot> printenv
ethaddr=3a:1f:34:08:54:54
bootdelay=3
baudrate=115200
stdin=serial
stdout=serial
stderr=serial
console=ttyS0,115200
root=/dev/mtdblock1
rw
rootfstype=jffs2"
bootargs=mem=256M memmap=exactmap memmap=0x08000000@0x20000000
memmap=0x08000000@0x70000000 console=ttyS0,115200 root=/dev/mtdblock1 rw
rootfstype=jffs2
bootcmd=nand read 0x72200000 0x00200000 0x0017CC38; bootm 0x72200000
ethact=macb0

Environment size: 412/131067 bytes





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