[U-Boot] RFC - how to support multipl DRAM chips in a single SPL build?

Wolfgang Denk wd at denx.de
Wed Mar 7 23:10:03 CET 2012

Dear Peter Barada,

In message <4F57A37C.8070501 at logicpd.com> you wrote:
> I'm trying to build a single SPL/u-boot that supports multiple Logic
> OMAP 35x/37x boards, with multiple configurations of DRAM/NAND/NOR. 

On ARM this is still not not exactly a rampant feature (and some
[mostly ARM] SoCs try to be clever and makeit extra hard for you),
but for a large number of boards this has been a standard feature
right since the beginning of U-Boot (and PPCBoot) twelf years ago.

> This is to make our support/production much simpler, and allow one
> SPL/u-boot "just work" on all or various boards.  To do so I need to
> figure out:
> 1) Probe for different DDR/NAND chips
> 2) Probe for multiple configurations of NOR/NAND

This is what get_ram_size() is good for.

> Any suggestions on an approach are much appreciated!

The normal approach is: set a configuration, run get_ram_size(), and
store the detected size. Repeat for all configurations. The
configuration that results in the biggest detected RAM size is the
correct one.

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Yes, it is written.  Good shall always destroy evil.
	-- Sirah the Yang, "The Omega Glory", stardate unknown

More information about the U-Boot mailing list