[coreboot] [PATCH] ASUS P2B-LS support, RAM detection for 440BX, add Slot 1 CPU, Microcode for Intel Tualatin CPUs

Joseph Smith joe at settoplinux.org
Thu Mar 4 13:38:45 CET 2010

On 03/04/2010 07:30 AM, Uwe Hermann wrote:
> On Thu, Mar 04, 2010 at 10:05:57AM +0000, Mark Marshall wrote:
>> On 03/03/10 04:19, Keith Hui wrote:
>>> Hi all,
>>> This thing is now ready for more exposure. Scratch my previous "patch" -
>>> this is my first real deal.
>>> - Adds RAM detection for i440bx (based on i82830 code). We're no longer
>>> hard coded for 64MB on one row!
>> Hi.
>> I've tried this with my ASUS P2B, and it's not quite there yet.
>> The first problem is that this motherboard only has three DIMM
>> slots. This means you have to set SDRAMC to something different;
>> 0x0103 works for me.
>> I'm guessing that we will need a motherboard config option for this
>> - there doesn't seem to be one suitable?  Something like:
>> src/mainboard/asus/p2b/Kconfig:
>> config DIMM_SOCKETS
>> 	int
>> 	default 3
>> 	depends on BOARD_ASUS_P2B
> Yes, sounds good. We will either need this, or maybe the settings can be
> auto-detected / probed (need to check datasheet, but I guess it's unlikely).
> Hm, seems to be determined by SDRAMPWR + MMCONFIG, and MMCONFIG seems to
> be a hardware-strap (so we can check it), but not sure about SDRAMPWR.
>> The second problem is that it doesn't work with more that 256 MB of
>> memory.  I've had one stick of 128 MB work, two sticks of 128 MB and
>> one stick of 256 MB all work, but two sticks of 256 MB doesn't boot
>> linux.
> Hm, will investigate. Are you sure both 256MB DIMMs work under vendor
> BIOS (so we can exclude hardware issues)?
> Thanks for testing!
One thing I noticed about Keith's code is he didn't impliment the 
initializing one row/side of memory at a time. I think it should really 
be visited, for multiple memory sticks.

Joseph Smith

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