From owner-freebsd-hardware Wed May 21 21:16:31 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.5/8.8.5) id VAA28840 for hardware-outgoing; Wed, 21 May 1997 21:16:31 -0700 (PDT) Received: from genesis.atrad.adelaide.edu.au (genesis.atrad.adelaide.edu.au [129.127.96.120]) by hub.freebsd.org (8.8.5/8.8.5) with ESMTP id VAA28831 for ; Wed, 21 May 1997 21:16:27 -0700 (PDT) Received: (from msmith@localhost) by genesis.atrad.adelaide.edu.au (8.8.5/8.7.3) id NAA17969; Thu, 22 May 1997 13:45:54 +0930 (CST) From: Michael Smith Message-Id: <199705220415.NAA17969@genesis.atrad.adelaide.edu.au> Subject: Re: isa bus and boca multiport boards In-Reply-To: <3.0.1.32.19970521074016.00736a68@lariat.org> from Brett Glass at "May 21, 97 07:40:16 am" To: brett@lariat.org (Brett Glass) Date: Thu, 22 May 1997 13:45:53 +0930 (CST) Cc: msmith@atrad.adelaide.edu.au, rberndt@nething.com, WELCHDW@wofford.edu, HARDWARE@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL28 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-hardware@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Brett Glass stands accused of saying: > At 01:34 PM 5/21/97 +0930, Michael Smith wrote: > > >(cocks an ear listening for the ICBM leaving bde's desk). > > > >I don't think that would be a very popular idea; the sio driver should be > >more, not less, machine independant. > > It's already hopelessly machine-dependent, due to the nature of the quirky > UARTs and edge-triggered interrupts. The 16550 is by no means unique to the PC architecture, nor is polling for repeat business inside an interrupt handler. Neither of these features make the driver particularly machine-dependant. >I don't think there's much value in > trying to maintain machine independence in the inner loops, where the C > code is slowing things down. But even with C, many optimizations would be > possible, as described in my message. It would appear that not everyone, least of all the maintainer of the code in question, agrees with your sentiments here 8) > I've noticed a significant slowdown with the latest drivers, and would > really like the speed back! Can you link this percieved slowdown to any particular change(s)? The basic structure of the sio driver hasn't changed "recently". > --Brett -- ]] Mike Smith, Software Engineer msmith@gsoft.com.au [[ ]] Genesis Software genesis@gsoft.com.au [[ ]] High-speed data acquisition and (GSM mobile) 0411-222-496 [[ ]] realtime instrument control. (ph) +61-8-8267-3493 [[ ]] Unix hardware collector. "Where are your PEZ?" The Tick [[