From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shards.monkeyblade.net (shards.monkeyblade.net [184.105.139.130]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40BmhS2dDMzDqh1 for ; Fri, 30 Mar 2018 01:04:22 +1100 (AEDT) Date: Thu, 29 Mar 2018 10:04:14 -0400 (EDT) Message-Id: <20180329.100414.1839699928682052200.davem@davemloft.net> To: okaya@codeaurora.org Cc: benh@kernel.crashing.org, torvalds@linux-foundation.org, alexander.duyck@gmail.com, will.deacon@arm.com, arnd@arndb.de, jgg@ziepe.ca, David.Laight@aculab.com, oohall@gmail.com, linuxppc-dev@lists.ozlabs.org, linux-rdma@vger.kernel.org, alexander.h.duyck@redhat.com, paulmck@linux.vnet.ibm.com, netdev@vger.kernel.org, linus971@gmail.com Subject: Re: RFC on writel and writel_relaxed From: David Miller In-Reply-To: <29fe17e0-9978-dc43-d02c-de8fabdc66c2@codeaurora.org> References: <1522249996.21446.25.camel@kernel.crashing.org> <20180328.115509.481837809903086401.davem@davemloft.net> <29fe17e0-9978-dc43-d02c-de8fabdc66c2@codeaurora.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Sinan Kaya Date: Thu, 29 Mar 2018 09:56:01 -0400 > sparc question sent Sparc never lets physical memory accesses pass MMIO, and vice versa. They are always strongly ordered amongst eachother. Therefore no explicit barrier instructions are necessary.