From: Liem Pham Tan <tanliemph@gmail.com>
To: linux-omap-open-source@linux.omap.com
Subject: Process 32-bit data without endianess-conversion between ARM – DSP?
Date: Tue, 10 Oct 2006 12:14:43 +0700 [thread overview]
Message-ID: <452B2C43.9010508@gmail.com> (raw)
Hi All,
I’m using DSP/BIOS LINK 1.10.1 to communicate between ARM and DSP on
OMAP5912.
I need to process 32-bit data on both ARM and DSP. The problem is DSP
uses big-endian and ARM uses little-endian.
The application note “Using Endianess Conversion in the OMAP5912 device”
(SWPA027) stated that : if both MPU and DSP access the data using the
same access size, then no endianess conversion is needed.
But when I pass data between them, the DSP always perform an
word-endianess conversion (16-bit). For example : If I write 0x00000001
on GPP and send via DSP/BIOS LINK to DSP, the data on DSP will be read
0x00010000 (and vice versa). I used Int32 on GPP and long on DSP
(32-bit) to access the buffer.
The DSP endianess can be controlled by the DSP MMU endianess control
register, but I can’t find any good way to set this register in DSP/BIOS
LINK ( I did try to set the channel attribute to ChannelDataSize_32bits*
*but it didn’t work).
Do you have any ideas on this problem?
Best regards,
Liem Pham
reply other threads:[~2006-10-10 5:14 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=452B2C43.9010508@gmail.com \
--to=tanliemph@gmail.com \
--cc=linux-omap-open-source@linux.omap.com \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.