From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <d8dd28679dc7183cf603a4969884ffca@plan9.bell-labs.com>
To: 9fans@cse.psu.edu
From: Sape Mullender <sape@plan9.bell-labs.com>
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Subject: [9fans] kernel/graphics slowness
Date: Wed,  1 May 2002 12:58:51 -0400
Topicbox-Message-UUID: 832cca1c-eaca-11e9-9e20-41e7f4b1d025

Some of you reported slow to extremely slow graphics operations.
We found the cause; it's a bug in the usb driver.  You can apply this
fix to usbuhci.c:

diff /n/dump/2002/0501/sys/src/9/pc/usbuhci.c usbuhci.c
1483,1484c1483
< 	ctlr->ctlq->head = PCIWADDR(ctlr->bwsop) | IsQH;
< 	ctlr->bwsop->head = PCIWADDR(ctlr->bulkq) | IsQH;
---
> 	ctlr->ctlq->head = PCIWADDR(ctlr->bulkq) | IsQH;
1486c1485,1489
< 	ctlr->recvq->head = PCIWADDR(ctlr->bwsop) | IsQH;	/* loop back */
---
> 	ctlr->recvq->head = PCIWADDR(ctlr->bwsop) | IsQH;
> 	if (1)	/* set up loop back */
>  		ctlr->bwsop->head = Terminate;
> 	else
> 		ctlr->bwsop->head = PCIWADDR(ctlr->bwsop) | IsQH;