[LinuxBIOS] problem about dram init

[aaron lwe]

On Thu, Dec 20, 2007 at 04:49:32PM +0800, aaron lwe wrote:
> I've configured the via cn700 dram controller

*..
> Unexpected Exception: 6 @ 10:1bfee821 - Halting

*..
> can I say ram is initialized right?

*
//No. ram_check() is a useless metric.
//Until you can successfully run memtest86 as a payload and it reports
//zero errors, RAM has not yet been configured correctly.

OK, I get it. Thanks.
Memtest86 reports errors at memory address
1MB, 5MB, 9MB, 13MB, 17MB, ... not sure what's wrong.

//I think Corey got things going on the CN700, are you working from
//his patch?
yes, I used corey's cn700 patch, and after changed some values I can run
ram_check successfully,
but as you have said, it's not quite useful...
corey's original patch couldn't pass ram_check, and I have no idea why.

[Peter Stuge]

On Thu, Dec 20, 2007 at 10:34:15PM +0800, aaron lwe wrote:
> //Until you can successfully run memtest86 as a payload and it reports
> //zero errors, RAM has not yet been configured correctly.
>
> OK, I get it. Thanks.
> Memtest86 reports errors at memory address
> 1MB, 5MB, 9MB, 13MB, 17MB, ... not sure what's wrong.

Many addresses around there or only exactly 1MB, 5MB etc?
> corey's original patch couldn't pass ram_check, and I have no idea
> why.

Probably some small differences between your board and his, which is
causing timing problems between the memory controller and RAM. :(

//Peter

[Corey Osgood]

aaron lwe wrote:
> On Thu, Dec 20, 2007 at 04:49:32PM +0800, aaron lwe wrote:
> > / I've configured the via cn700 dram controller
>
> /..
> > / Unexpected Exception: 6 @ 10:1bfee821 - Halting
>
> /..
> > / can I say ram is initialized right?
>
> /
> //No. ram_check() is a useless metric.
> //Until you can successfully run memtest86 as a payload and it reports
> //zero errors, RAM has not yet been configured correctly.
>
> OK, I get it. Thanks.
> Memtest86 reports errors at memory address
> 1MB, 5MB, 9MB, 13MB, 17MB, ... not sure what's wrong.

Weird, I've never seen that problem. Do you have any other dram modules
you can try? Can you send me the specs (or a link to the datasheet would
be best) on the module you're currently using? I have some comments I
need to put in about some important bits, but haven't had the time or
ambition lately to do it. Eventually those bits should be set up
automatically, but I'm running up against ROMCC's limitations.

-Corey

[Uwe Hermann]

On Thu, Dec 20, 2007 at 10:42:33AM -0500, Corey Osgood wrote:
> Weird, I've never seen that problem. Do you have any other dram modules
> you can try? Can you send me the specs (or a link to the datasheet would
> be best) on the module you're currently using? I have some comments I
> need to put in about some important bits, but haven't had the time or
> ambition lately to do it. Eventually those bits should be set up
> automatically, but I'm running up against ROMCC's limitations.

There are some other tricks like disabling/removing debugging stuff
etc., but one thing that helped me on some other board is a
different -mcpu option for romcc, e.g.

action  "./romcc -mcpu=p2 -O -I$(TOP)/src -I. $(CPPFLAGS) $(MAINBOARD)/auto.c -o $@"

Without the '-mcpu=p2' I get 'too few registers', adding it fixes that
problem. Depending on the CPU/chipset values other than 'p2' might work.
Basically, it allows romcc to use more registers, I think, but I'm not
a romcc expert, just guessing...

HTH, Uwe.

[aaron lwe]

On Dec 20, 2007 11:42 PM, Corey Osgood  wrote:
> aaron lwe wrote:
> > On Thu, Dec 20, 2007 at 04:49:32PM +0800, aaron lwe wrote:
> > > / I've configured the via cn700 dram controller
> >
> > /..
> > > / Unexpected Exception: 6 @ 10:1bfee821 - Halting
> >
> > /..
> > > / can I say ram is initialized right?
> >
> > /
> > //No. ram_check() is a useless metric.
> > //Until you can successfully run memtest86 as a payload and it reports
> > //zero errors, RAM has not yet been configured correctly.
> >
> > OK, I get it. Thanks.
> > Memtest86 reports errors at memory address
> > 1MB, 5MB, 9MB, 13MB, 17MB, ... not sure what's wrong.
>
> Weird, I've never seen that problem. Do you have any other dram modules
> you can try? Can you send me the specs (or a link to the datasheet would
> be best) on the module you're currently using? I have some comments I
> need to put in about some important bits, but haven't had the time or
> ambition lately to do it. Eventually those bits should be set up
> automatically, but I'm running up against ROMCC's limitations.
>
> -Corey

Sorry for the lack of information. The module I'm using is Kingston
KVR533D2N4/512,
the datasheet I can find is at http://
www.valueram.com/datasheets/KVR533D2N4_512.pdf
but it doesn't give too much information.
internal bank is 4, external bank(or rank) is 1. row is 14, column is 10,
primary data width is 8bits
it's single sided.
following is the dump of spd info:
00: 80 08 08 0e 0a 60 40 00 05 3d 50 00 82 08 00 00
10: 0c 04 38 00 02 00 30 3d 50 50 60 3c 1e 3c 2d 80
20: 25 38 10 23 3c 1e 1e 00 00 3c 69 80 1e 28 00 00
30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 10 e1
40: 7f 98 00 00 00 00 00 00 01 00 00 00 00 00 00 00
50: 00 00 00 00 00 00 00 00 00 00 00 00 00 06 10 83
60: 2d 74 0f 00 00 00 00 00 00 00 00 00 00 00 00 00
70: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
f0: 39 39 30 35 32 36 30 2d 30 30 31 2e 43 30 31 4c

I'll try another ddr2 module once I find one.
Thank you all.

[ron minnich]

On Dec 20, 2007 6:34 AM, aaron lwe  wrote:
> OK, I get it. Thanks.
> Memtest86 reports errors at memory address
> 1MB, 5MB, 9MB, 13MB, 17MB, ... not sure what's wrong.

we need to know a lot more about that module first!

what parts? double sided? how many banks? etc. etc.

Then we can form a guess.

thanks

ron