From mboxrd@z Thu Jan 1 00:00:00 1970 From: khc@pm.waw.pl (Krzysztof Halasa) Date: Wed, 25 Nov 2009 00:45:21 +0100 Subject: IXP425: help on HSS channelized service In-Reply-To: <4B0BDFC1.7010506@kaskonetworks.it> (Davide Di Gesualdo's message of "Tue, 24 Nov 2009 14:29:37 +0100") References: <4B0BDFC1.7010506@kaskonetworks.it> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Davide Di Gesualdo writes: > I'm writing a kernel module for a HSS channelized service on IXP425 > processor, based on ixp4xx_hss. I'm developing on a IXDPG425 Intel > board, and the HSS bus is attached to four Si3210 ProSLIC chips. > The purpose of this module is to read/write from/to HSS 8-byte buffers > in raw mode (no particular alignment is required). In write direction, > everything seems ok: if I write a buffer like > char buf[] = {0xcb, 0xcb, 0xcb, 0xcb, 0xcb, 0xcb, 0xcb, 0xcb}; > on a fixed timeslot and then read the TXD pin signal with a scope, I > can see the correct waveform at the correct place; I've also tried to > write a tone with a fixed freqeuncy, and I've listened it correctly. > The problem comes with read direction: I've tried to make a loopback > by copying the rxbuffer in the txbuffer, but I can't hear my voice > back (instead I hear something like a continous buzz). I'm quite sure > I read the rxbuffer in the correct way (I do the same when I write > txbuffer, which works properly!). The buffers have different structures for RX and TX. > This is the ISR for HSS > read-complete interrupt: Looks like a modified code from one of my ixp4xx-[0-9][0-9] branch. Have you tried using the original code in e.g. ixp4xx-31? You may need to make some trivial changes related to "MVIP". Not that my channelized HSS code is flawless or something, far from it, but it works, both directions. -- Krzysztof Halasa