From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752359AbcHNO0T (ORCPT ); Sun, 14 Aug 2016 10:26:19 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:48900 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750975AbcHNO0S (ORCPT ); Sun, 14 Aug 2016 10:26:18 -0400 X-IBM-Helo: d03dlp01.boulder.ibm.com X-IBM-MailFrom: aneesh.kumar@linux.vnet.ibm.com From: "Aneesh Kumar K.V" To: Christophe Leroy , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Scott Wood Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH 6/6] powerpc/8xx: implementation of huge pages In-Reply-To: <15e0fa7a312245e681cb9ca18ffb875c7820e5fc.1471020647.git.christophe.leroy@c-s.fr> References: <15e0fa7a312245e681cb9ca18ffb875c7820e5fc.1471020647.git.christophe.leroy@c-s.fr> User-Agent: Notmuch/0.21 (https://notmuchmail.org) Emacs/24.5.1 (x86_64-pc-linux-gnu) Date: Sun, 14 Aug 2016 19:55:30 +0530 MIME-Version: 1.0 Content-Type: text/plain X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16081414-0016-0000-0000-0000046A6F8D X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00005593; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000181; SDB=6.00744516; UDB=6.00350758; IPR=6.00517057; BA=6.00004660; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00012334; XFM=3.00000011; UTC=2016-08-14 14:25:37 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16081414-0017-0000-0000-000031FFEDD0 Message-Id: <8760r3a0md.fsf@skywalker.in.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2016-08-14_02:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1604210000 definitions=main-1608140219 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christophe Leroy writes: > The 8xx has 512k and 8M pages. This patch implements hugepages using > those sizes. > > On the 8xx, the size of pages is in the PGD entry, > using PS field (bits 28-29): > 00 : Small pages (4k or 16k) > 01 : 512k pages > 10 : reserved > 11 : 8M pages > > The implementation uses a mix of what is used on BOOKS and BOOKE, > as 512k pages are in HUGEPTE tables while for 8M pages we have > several PGD entries pointing on a leaf HUGEPTE entry > > For the time being, we do not support CPU15 ERRATA if HUGETLB is > selected Can you also document here the format for linux page table with different huge page size. ? > > Signed-off-by: Christophe Leroy