Date: Mon, 14 Jul 1997 08:57:48 +0200 (MET DST) From: Luigi Rizzo <luigi@labinfo.iet.unipi.it> To: rhh@ct.picker.com (Randall Hopper) Cc: hasty@rah.star-gate.com, multimedia@FreeBSD.ORG Subject: Re: guspnp9: strange dma #s in probe output Message-ID: <199707140657.IAA10172@labinfo.iet.unipi.it> In-Reply-To: <19970713204557.61315@ct.picker.com> from "Randall Hopper" at Jul 13, 97 08:45:38 pm
next in thread | previous in thread | raw e-mail | index | archive | help
> I noticed that in the verbose probe output from the sound driver, that > there are "two" DMAs being printed for the "sb" and "sbxvi" devices. They > each only use one. > > The should be sb = 1 and sbxvi = 5. It's printing sb = 1,7; sbxvi = 5,7. > > Does this indicate a problem, or should I ignore it? I think I know where the problem is. The "flags" field is misused to hold the secondary dma channel, but originally 0 meant no secondary dma. Now it appears that some PnP cards that I have default to use DMA 0 as the secondary DMA, so I had to patch the code in order to make this possible. The solution I used was to use the low three bits as dma address, and an additional bit to flag that the secondary dma address was used. Because of this masking, the "-1" which is the internal representation of "no secondary dma" has become 7. This might or might not cause problems later, so better check it. Thanks for pointing this out. Cheers Luigi -----------------------------+-------------------------------------- Luigi Rizzo | Dip. di Ingegneria dell'Informazione email: luigi@iet.unipi.it | Universita' di Pisa tel: +39-50-568533 | via Diotisalvi 2, 56126 PISA (Italy) fax: +39-50-568522 | http://www.iet.unipi.it/~luigi/ _____________________________|______________________________________
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199707140657.IAA10172>