From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9518FC43381 for ; Tue, 19 Feb 2019 14:16:21 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1415221773 for ; Tue, 19 Feb 2019 14:16:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1415221773 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 443jTG3mlTzDqLx for ; Wed, 20 Feb 2019 01:16:18 +1100 (AEDT) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 443jR96JqGzDqD2 for ; Wed, 20 Feb 2019 01:14:29 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Received: by ozlabs.org (Postfix) id 443jR94Xd8z9sDL; Wed, 20 Feb 2019 01:14:29 +1100 (AEDT) Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPSA id 443jR92l0zz9s5c; Wed, 20 Feb 2019 01:14:29 +1100 (AEDT) From: Michael Ellerman To: Christophe Leroy , linuxppc-dev@ozlabs.org Subject: Re: [PATCH] powerpc: Make PPC_64K_PAGES depend on only 44x or PPC_BOOK3S_64 In-Reply-To: <2fc1837d-af23-751c-d9af-0d0888b26ab4@c-s.fr> References: <20190208123416.1051-1-mpe@ellerman.id.au> <2fc1837d-af23-751c-d9af-0d0888b26ab4@c-s.fr> Date: Wed, 20 Feb 2019 01:14:25 +1100 Message-ID: <87h8czc1by.fsf@concordia.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: oss@buserror.net, aneesh.kumar@linux.vnet.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Christophe Leroy writes: > On 02/08/2019 12:34 PM, Michael Ellerman wrote: >> In commit 7820856a4fcd ("powerpc/mm/book3e/64: Remove unsupported >> 64Kpage size from 64bit booke") we dropped the 64K page size support >> from the 64-bit nohash (Book3E) code. >> >> But we didn't update the dependencies of the PPC_64K_PAGES option, >> meaning a randconfig can still trigger this code and cause a build >> breakage, eg: >> arch/powerpc/include/asm/nohash/64/pgtable.h:14:2: error: #error "Page size not supported" >> arch/powerpc/include/asm/nohash/mmu-book3e.h:275:2: error: #error Unsupported page size >> >> So remove PPC_BOOK3E_64 from the dependencies. This also means we >> don't need to worry about PPC_FSL_BOOK3E, because that was just trying >> to prevent the PPC_BOOK3E_64=y && PPC_FSL_BOOK3E=y case. > > Does it means some cleanup could be done, for instance: > > arch/powerpc/include/asm/nohash/64/pgalloc.h:#ifndef CONFIG_PPC_64K_PAGES > arch/powerpc/include/asm/nohash/64/pgalloc.h:#endif /* > CONFIG_PPC_64K_PAGES */ > arch/powerpc/include/asm/nohash/64/pgtable.h:#ifdef CONFIG_PPC_64K_PAGES > arch/powerpc/include/asm/nohash/64/slice.h:#ifdef CONFIG_PPC_64K_PAGES > arch/powerpc/include/asm/nohash/64/slice.h:#else /* CONFIG_PPC_64K_PAGES */ > arch/powerpc/include/asm/nohash/64/slice.h:#endif /* > !CONFIG_PPC_64K_PAGES */ > arch/powerpc/include/asm/nohash/pte-book3e.h:#ifdef CONFIG_PPC_64K_PAGES > > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */ > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */ > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#endif /* CONFIG_PPC_64K_PAGES */ > arch/powerpc/mm/tlb_low_64e.S:#ifndef CONFIG_PPC_64K_PAGES > arch/powerpc/mm/tlb_low_64e.S:#ifdef CONFIG_PPC_64K_PAGES Probably. Some of the FSL chips do support 64K pages at least according to some datasheets. I don't know what would be required to get it working, or if it even works in practice. So it would be nice to get 64K working on those chips, but probably no one has time or motivation to do it. In which case yeah all that code should be removed. cheers