From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754331AbaDCI7I (ORCPT ); Thu, 3 Apr 2014 04:59:08 -0400 Received: from fw-tnat.austin.arm.com ([217.140.110.23]:52818 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751215AbaDCI67 (ORCPT ); Thu, 3 Apr 2014 04:58:59 -0400 Date: Thu, 3 Apr 2014 09:58:35 +0100 From: Catalin Marinas To: Joe Sylve Cc: Will Deacon , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH 1/1] AArch64: TCR_TG1_64K incorrectly sets TCR_EL1 bits [31:30] Message-ID: <20140403085835.GC17022@arm.com> References: <20140402123844.GE31892@arm.com> <20140402170747.GC24018@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 02, 2014 at 06:21:29PM +0100, Joe Sylve wrote: > That makes sense and I agree, it's better to fix it now so that it > will be easier to add 16K paging later (on a side note is there any > reason not to add it now if someone was willing to do the work?). See another thread with the Samsung folks about the adding 4-levels of page tables. We need a bit of refactoring first to decouple the page size from the number of levels, after that 16K would be relatively easy (it's easy now as well but I don't see the point on doing it before the refactoring). > There was talk in another thread about the possibility of adding a > pagetable-4K-hwdef.h and pagetable-64K-hwdef.h. I think this is > another example of why that might be a good idea as this stuff could > be moved out of proc.S as to be bit more clean: > > +#ifdef CONFIG_ARM64_64K_PAGES > +#define TCR_TG_FLAGS TCR_TG0_64K | TCR_TG1_64K > +#else > +#define TCR_TG_FLAGS TCR_TG0_4K | TCR_TG1_4K > +#endif Yes, we could do this when we create the pgtable-*k-hwdef.h files. -- Catalin