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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 0DB8EC47E49 for ; Mon, 21 Oct 2019 14:35:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D06B520656 for ; Mon, 21 Oct 2019 14:35:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D06B520656 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7C8ED6B0006; Mon, 21 Oct 2019 10:35:30 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 779B06B0007; Mon, 21 Oct 2019 10:35:30 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 68F1B6B0008; Mon, 21 Oct 2019 10:35:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0221.hostedemail.com [216.40.44.221]) by kanga.kvack.org (Postfix) with ESMTP id 425756B0006 for ; Mon, 21 Oct 2019 10:35:30 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with SMTP id C2C51181AEF10 for ; Mon, 21 Oct 2019 14:35:29 +0000 (UTC) X-FDA: 76068039978.25.crime33_4d0a56f432123 X-HE-Tag: crime33_4d0a56f432123 X-Filterd-Recvd-Size: 3894 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Mon, 21 Oct 2019 14:35:29 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 98FCAAE65; Mon, 21 Oct 2019 14:35:27 +0000 (UTC) Message-ID: <78caa5bcfc0d59e8ec5d6b7060df76896d25248b.camel@suse.de> Subject: Re: [PATCH v6 3/4] arm64: use both ZONE_DMA and ZONE_DMA32 From: Nicolas Saenz Julienne To: Qian Cai Cc: f.fainelli@gmail.com, mbrugger@suse.com, marc.zyngier@arm.com, catalin.marinas@arm.com, robin.murphy@arm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Rob Herring , wahrenst@gmx.net, m.szyprowski@samsung.com, phill@raspberrypi.org, will@kernel.org, Christoph Hellwig , linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org Date: Mon, 21 Oct 2019 16:34:58 +0200 In-Reply-To: <3956E54B-6C7A-4C47-B9B6-75F556EFD3F5@lca.pw> References: <20190911182546.17094-1-nsaenzjulienne@suse.de> <20190911182546.17094-4-nsaenzjulienne@suse.de> <3956E54B-6C7A-4C47-B9B6-75F556EFD3F5@lca.pw> Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="=-h82UrL74CNp2lRPKbz+/" User-Agent: Evolution 3.32.4 MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: --=-h82UrL74CNp2lRPKbz+/ Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2019-10-21 at 10:15 -0400, Qian Cai wrote: > > On Sep 11, 2019, at 2:25 PM, Nicolas Saenz Julienne > > wrote: > >=20 > > So far all arm64 devices have supported 32 bit DMA masks for their > > peripherals. This is not true anymore for the Raspberry Pi 4 as most of > > it's peripherals can only address the first GB of memory on a total of > > up to 4 GB. > >=20 > > This goes against ZONE_DMA32's intent, as it's expected for ZONE_DMA32 > > to be addressable with a 32 bit mask. So it was decided to re-introduce > > ZONE_DMA in arm64. > >=20 > > ZONE_DMA will contain the lower 1G of memory, which is currently the > > memory area addressable by any peripheral on an arm64 device. > > ZONE_DMA32 will contain the rest of the 32 bit addressable memory. > >=20 > > Signed-off-by: Nicolas Saenz Julienne > > Reviewed-by: Catalin Marinas > >=20 > > --- >=20 > With ZONE_DMA=3Dy, this config will fail to reserve 512M CMA on a server, >=20 > https://raw.githubusercontent.com/cailca/linux-mm/master/arm64.config >=20 > CONFIG_DMA_CMA=3Dy > CONFIG_CMA_SIZE_MBYTES=3D64 > CONFIG_CMA_SIZE_SEL_MBYTES=3Dy > CONFIG_CMA_ALIGNMENT=3D8 > CONFIG_CMA=3Dy > CONFIG_CMA_DEBUGFS=3Dy > CONFIG_CMA_AREAS=3D7 >=20 > Is this expected? Not really, just tested cma=3D512M on a Raspberry Pi4, and it went well. Th= e only thing on my build that differs from your config is CONFIG_CMA_DEBUGFS. Could you post more information on the device you're experiencing this on? = Also some logs. Regards, Nicolas --=-h82UrL74CNp2lRPKbz+/ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQEzBAABCAAdFiEErOkkGDHCg2EbPcGjlfZmHno8x/4FAl2twhIACgkQlfZmHno8 x/4U7Qf/ZdG/T1u3Mhd7QimbgwhtDy+7HOxKrFVl2JndkuRooQ8OQlTx7pwRnOow auWVm83R9XgT9N2n6+0ZHYUWcgjmqoSkGurnJPeZjONQdFmEZDvcB/mgTb4u/a1N QC79LCo67Gk2V7jdkVdsijNirVn4JfZQ+mFUDSd9CJkVsbdFLq00q/3z30xoiPNm m1GVAN9xvxKouoYtmKJ50IZ87keEjg2+Fqvxubu2Kzjf2Vsfyl6IjJ2opV10JqmL baHrRu5QJteP3WS/MIHp2VbGAz0wNaEJ7f7cHeow4vnWrKRPPHk80b0nyMXzCr8d RjT2ZFo/VrFpdG8Ik6gtKmn2VdAeug== =V9f2 -----END PGP SIGNATURE----- --=-h82UrL74CNp2lRPKbz+/--