From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Mon, 26 Apr 2004 19:25:03 +0000 Subject: Re: cacheble to uncachble change Message-Id: <16525.25103.572166.675668@napali.hpl.hp.com> List-Id: References: <408D5C58.E07A5FBE@email.mot.com> In-Reply-To: <408D5C58.E07A5FBE@email.mot.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org >>>>> On Mon, 26 Apr 2004 14:00:40 -0500, Mario Smarduch said: Mario> Is there support in IA64 kernel to change a memory mapping Mario> from cacheble to uncacheble attribute. By support I mean one Mario> function which can accept an addr start/range, make sure Mario> in-transit cache data/prefetch hits are synced and upon Mario> return gurantee no CPU has any stale data in its caches and Mario> after installing the new attribute memory is guranteed Mario> synchronized. Or is a combonition of functions/macros Mario> required? Volume 2 (System Architecture) of the ASDM outlines the steps needed to do such a transition. All the necessary primitives should be there in ia64 linux, but there is no single convenient-to-use function to do this. In any case, just be careful about not introducing memory attribute aliases. You need to be especially careful since the kernel accesses memory with granule-sized mappings (normally 64MB page size, but on some machines its 16MB). --david