pxa300 - DDRAM base value

[Marek Vasut]

Dne Po 7. června 2010 08:29:51 balakrishnan napsal(a):
> On Sun, 2010-06-06 at 18:34 +0200, Marek Vasut wrote:
> > Dne Ne 6. června 2010 10:17:00 Eric Miao napsal(a):
> > > On Sun, Jun 6, 2010 at 1:19 AM, Marek Vasut <marek.vasut at gmail.com> wrote:
> > > > Dne Út 1. června 2010 07:44:18 balakrishnan napsal(a):
> > > >> I am working on pxa300 based development board and using Linux
> > > >> 2.6.34. This Linux kernel already has support for following boards
> > > >> 1. zylonite_pxa300
> > > >> 2. cm-x300
> > > >> 3. colibri-pxa300
> > > >> 4. littleton
> > > >> 
> > > >> My doubt is that pxa300 based boards are using "0xa0000000"  as
> > > >> DDRAM base and PHYS_OFFSET is also defined in
> > > >> "arch/arm/mach-pxa/include/mach/memory.h" as 0xa0000000.
> > > >> But in our board  DDR is mapped in 0x80000000. Does it make any
> > > >> problem?. Because after mmu is turned ON, my board is hanging.
> > > >> 
> > > >> "zreladdr-y   := 0x80008000" is defined in
> > > >> "arch/arm/mach-pxa/Makefile.boot" file .
> > > >> my machine_desc is as follows
> > > >> .phys_io        = 0x40000000,
> > > >> .io_pg_offst    = (io_p2v(0x40000000) >> 18) & 0xfffc,
> > > >> .boot_params    = 0x80000100,
> > > > 
> > > > Try editing both arch/arm/mach-pxa/Makefile.boot and
> > > > arch/arm/mach/pxa/include/mach/memory.h
> > > > 
> > > >> With Thanks
> > > >> J.Balakrishnan
> > > > 
> > > > The 0x80000000 should be aliased to 0xa0000000, but looking into the
> > > > PXA docs, it is only on pxa320. Eric, any ideas on this ?
> > > 
> > > Should be working on pxa300/310 as well. If it doesn't, check you
> > > bootloader to make sure the mapping is OK, and memory doesn't exceed
> > > (0xa000_0000 - 0x8000_0000).
> > 
> > It worked last time I used the pxa310 littleton board, but I can't check
> > on the pxa300 zylonite board just yet.
> > 
> > Could you give us your bootloader details ?
> 
> hi,
>       Now, I can able to boot after editing following files
> arch/arm/mach-pxa/Makefile.boot and
> arch/arm/mach/pxa/include/mach/memory.h (0x80000000 changed to
> 0xa0000000). My doubt is

It was always set to 0xa0000000, both of them.

> 1.why 0x80000000 (DDR phy address) is aliased to 0xa0000000 in pxa
> architecture?

Because that's how the HW guys did it and because it's written in TRM (which is 
the holy bible(substitute any other holy object) of the CPU) ;-)

> 2.In my development board two DDRAMs mapped at 0x80000000-0x88000000 and
> 0xc0000000-0xc8000000, how can I inform to kernel about this different
> bank and size?.

Check LAKML and look for:
"[PATCH] pxa/vpac270: Enable SparseMEM for 256 MB of RAM"

This might give you an idea ... though it's a hack. All this goo about 
PHYS_OFFSET etc. will be gone in hopefully near future.

Cheers!

> 
> My Boot loader details,
> ------------------------------
> =>bdi
> arch_number = 0x00000B04
> env_t       = 0x00000000
> boot_params = 0x80000100
> DRAM bank   = 0x00000000
> -> start    = 0x80000000
> -> size     = 0x08000000
> DRAM bank   = 0x00000001
> -> start    = 0xC0000000
> -> size     = 0x08000000
> ethaddr     = 08:00:3e:26:0a:5b
> ip_addr     = 192.168.0.21
> baudrate    = 115200 bps
> =>ver
> U-Boot 2010.03 (Jun 01 2010 - 14:27:43)
> 
> 
> With Thanks
> J.Balakrishnan