On Fri, Jan 18, 2008 at 01:32:12PM -0700, Yang, Bo wrote: > Alan, > > The in/outb_p in MegaRAID scsi driver is used for our old io mapped > megaraid controller. There are still some customers are using those old > controller. Please keep them. Hi Bo, I think you've misunderstood the question. The '_p' versions of inb/outb introduce a delay after each access. The current Linux implementation of _p provokes bugs on some chipsets, so Alan is looking for alternatives. Let's ask the question like this: Replacing outb_p() with outb(); udelay(x); How large does 'x' need to be for these megaraid controllers? > Thanks. > > Bo Yang > > -----Original Message----- > From: Alan Cox [mailto:alan@xxxxxxxxxxxxxxxxxxx] > Sent: Friday, January 18, 2008 7:36 AM > To: linux-scsi@xxxxxxxxxxxxxxx; DL-MegaRAID Linux > Subject: Megaraid: Use of outb_p > > > I notice the MegaRAID driver uses outb_p. Can someone at LSI confirm > that the delays between each I/O are required, and if so how long they > must be. > > I'm trying to sort out the use of in/outb_p and where it is unneccessary > or used for non ISA devices. > > (Please cc me on the reply) > Alan > > - > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Intel are signing my paycheques ... these opinions are still mine "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step." - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
