December 2003 - ixp1200 - lists.cs.princeton.edu

I have a DMA question.
by Cho, joon-woo 02 Dec '03

02 Dec '03

Hello. Have anyone use IXP1200's DMA operation? I want to use DMA for transferring data from host computer's memory to IXP1200 evaluation board. Sure, my IXP1200 EB is attached to host computer through PCI slot. And I write Microengine program like below 1. Make DMA descriptor. 2. point tmp1 to DMA descritptor's address 3. And use pci_dma instruction like below pci_dma[tmp1, 0, any_queue], ctx_swap But, after pci_dma instruction, nothing is done more. Do I mistake? Or do you have similar situation? Please give me any advice. Thanks

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Sharing configurable data.
by Øyvind Hvamstad 02 Dec '03

02 Dec '03

(ENP2505 - linux embedded) Hi, I have "successfully" written a idl server for my app, to enable runtime configuration. Now, I like some of these settings to be shared between the StrongARM and the microengines. The l2bridge code uses the hdbm.h macros HDBM_READ_SRAM and HDBM_WRITE_SRAM to accomplish this. However, this file is in c++ and I use plain c. What is the right way for me to share SRAM memory? Could I use the Resource Manager interface Read/Write functions? Please tell me if I'm way off Also, how do I recover from a seg. fault? I'm unable to unload the ace after a crash, and after rebooting the board, it fails to reload the kernel. So I have to reboot the host carrier every time. (ARGH!) Is there a fix? (Tried killing) -- Øyvind Hvamstad <oyvindh(a)ifi.uio.no>

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interthread signal from the strongarm
by P.J.Simoons 01 Dec '03

01 Dec '03

Hi there, According to my book one can send an interthread signal from the strongarm by doing *((int*) 0xb00401c0) = thread_id; However since the signals are kept in a bitfield, wouldn't *((int*) 0xb00401c0) |= 1 << thread_id; be more appropriate? Yours, Pieter

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