Hi all,
On 01/02/2013 10.49, Luca Ellero wrote:
Hi,
On 01/02/2013 11.07, Heiko Schocher wrote:
Hello Luce,
Am 01.02.2013 09:50, schrieb Luca Ellero:
Hi Jeroen,
Hi Heiko,
On 31/01/2013 20.08, Jeroen Hofstee wrote:
Hello Luca,
On 01/31/2013 03:29 PM, Luca Ellero wrote:
If (N. SDRAM banks > 1) and they are not contiguous, don't relocate
u-boot at (CONFIG_SYS_SDRAM_BASE + gd->ram_size), which is a bug.
Instead use the end of 2nd bank (even if there are more than 2 banks)
Signed-off-by: Luca Ellero <lro...@gmail.com>
Cc: Albert Aribaud <albert.u.b...@aribaud.net>
Cc: Heiko Schocher <h...@denx.de>
---
On ARM architectures there is a bug getting top of SDRAM (where u-boot
will be relocated). Top of SDRAM will always be:
CONFIG_SYS_SDRAM_BASE + gd->ram_size
anyway this can be wrong since SDRAM can be composed by more that one
bank in not-contiguous address space.
I don't think this is a valid use case since the README says:
"The available memory is mapped to fixed addresses using the memory
controller. In this process, a contiguous block is formed for each
memory type (Flash, SDRAM, SRAM), even when it consists of several
physical memory banks."
Thank for your comments.
You are saying more or less the same thing but I'm afraid I didn't
really catch what you mean.
You have 2 memory banks which are not contiguos.
[...]
Now, I have a Freescale iMX53 LOCO board which have 2 banks of 512 MB
SDRAM, for total of 1GB. One bank is at phys 0x70000000-0x8fffffff, the
other is at 0xb0000000-0xcfffffff.
Here you have a gap from 0x90000000 - 0xafffffff between the two banks,
which U-Boot currently not supports ...
If I stop U-Boot execution after relocation (with a JTAG debugger) I see
that it is running at physical address 0xaff6D000 (more or less).
As far as I can see this address is not existent. And the dangerous part
is that I can see the same data (U-Boot code) at address 0x8ff6D000.
This clearly states that U-Boot is relocated at 0xAff6D000
but in reality it is at 0x8ff6D000 an the relocation can potentially
override data already existing there.
Don't you think this is a wrong behaviour?
This wrong behaviour results because you use U-Boot in a
configuration, which U-Boot currently not handle correct resp.
does not support ...
Why you need such a memory configuration?
I suggest to move the second bank (if possible) to 0x90000000
and you have a contiguos memory, and U-Boot should work fine.
That's exactly the point!!!
As far as I know iMX53 _can't_ physically move banks to other addresses.
And likely there are some other architectures that have the same behaviour.
Maybe someone on the list can confirm this.
Bye
Luca
Any news here?
If this patch isn't the proper way to fix this misbehaviour, please
suggest some other way to correct it. I'm a bit scary of viewing code
running in "not-existing" addresses :-)
Thanks
Regards
Luca
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