From mboxrd@z Thu Jan 1 00:00:00 1970 From: "David S. Miller" Date: Thu, 25 Apr 2002 00:08:08 +0000 Subject: [Linux-ia64] Re: PCI DAC routines for SN Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org From: Jesse Barnes Date: Wed, 24 Apr 2002 17:11:19 -0700 So if performance isn't an obstacle to implementing a new call, and I've shown that there are platforms where 64 bit consistent mappings are better to use than 32 bit mappings when possible, why can't we add it? Or maybe just a seperate consistent_mask that drivers could set to indicate they support the operation and let the platform take care of it? Where is the platform where it is a problem to keep around enough of the _4_ __GIGABYTES__ of consistent memory available at bootup? If you can't keep around enough consistent memory within the lower 4GB, you have other problems. Devices use, EACH, something like a few kilobytes of consistent memory for descriptors. If you are going to tell me this is a big deal, you have to be kidding me. Why don't you tell me what the real problem is?