From: marek.vasut@gmail.com (Marek Vasut)
To: linux-arm-kernel@lists.infradead.org
Subject: pxa300 - DDRAM base value
Date: Mon, 7 Jun 2010 21:43:16 +0200 [thread overview]
Message-ID: <201006072143.16136.marek.vasut@gmail.com> (raw)
In-Reply-To: <AANLkTinKc9Uc6QeKYogK3h1kHsOU1p6Qp1kWgn0J8cMA@mail.gmail.com>
Dne Po 7. ?ervna 2010 21:37:16 Mike Rapoport napsal(a):
> > 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
> > 1.why 0x80000000 (DDR phy address) is aliased to 0xa0000000 in pxa
> > architecture?
> > 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?.
>
> enable CONFIG_HIGHMEM
Mike, that wont help him as he has PHYS_OFFSET=0xa0000000 . Selecting
CONFIG_HIGHMEM will only cause the pages for RAM below 0xa0000000 to have
incorrectly computated descriptor addresses (or maybe will be ignored).
The page descriptors for RAM at PA 0xa0000000 are at VA 0xc0000000 + some offset
(there's an easy linear formula to compute their offset). Now if you feed that
formula with 0x80000000, the page descriptors will end below 0xc0000000, which
isn't a valid VA, therefore the descriptors will not be valid either (in the
better case, but it will hang the kernel at early stage anyway).
Therefore there are two ways -- either use what I suggested earlier or wait
until the PHYS_OFFSET is dynamically computated (check Eric's patchset).
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
> > _______________________________________________
> > linux-arm-kernel mailing list
> > linux-arm-kernel at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2010-06-07 19:43 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-06-01 5:44 pxa300 - DDRAM base value balakrishnan
2010-06-05 17:19 ` Marek Vasut
2010-06-06 8:17 ` Eric Miao
2010-06-06 16:34 ` Marek Vasut
2010-06-07 6:29 ` balakrishnan
2010-06-07 6:58 ` Marek Vasut
2010-06-07 19:37 ` Mike Rapoport
2010-06-07 19:43 ` Marek Vasut [this message]
2010-06-08 6:21 ` Mike Rapoport
2010-06-06 17:03 ` Mike Rapoport
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=201006072143.16136.marek.vasut@gmail.com \
--to=marek.vasut@gmail.com \
--cc=linux-arm-kernel@lists.infradead.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).