From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [RFC] asm-generic/pci_iomap.h: make custom PCI BAR requirements explicit Date: Sun, 04 Oct 2015 21:02:04 +0200 Message-ID: <8902671.32Mbh7QhE4@wuerfel> References: <1440807447-584-1-git-send-email-mcgrof@do-not-panic.com> <1866509.8pE0MIz57e@wuerfel> <20151002235346.GJ14464@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: In-Reply-To: <20151002235346.GJ14464@wotan.suse.de> Sender: linux-kernel-owner@vger.kernel.org To: "Luis R. Rodriguez" Cc: "Luis R. Rodriguez" , linux-arch@vger.kernel.org, mingo@kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, linux-s390@vger.kernel.org, bp@suse.de, linux@roeck-us.net, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, rostedt@goodmis.org List-Id: linux-arch.vger.kernel.org On Saturday 03 October 2015 01:53:46 Luis R. Rodriguez wrote: > > > > Hmm, my gut feeling tells me that your approach won't solve the problem > > in general. s390 PCI is just weird in many ways and it will occasionally > > suffer from problems like this (as do other aspects of the s390 architecture > > that are unlike the rest of the world). > > > > Maybe Martin and Heiko can comment on this, they may have a preference > > from the s390 point of view. > > Hrm, so S390 is quirky is really odd ways that no other architecture is or > is at least for now not expected to be ? Absolutely correct. It is the only architecture I'm aware of that tries to support PCI that does not use pointer dereferences for MMIO. Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.kundenserver.de ([212.227.126.187]:55561 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751518AbbJDTCN (ORCPT ); Sun, 4 Oct 2015 15:02:13 -0400 From: Arnd Bergmann Subject: Re: [RFC] asm-generic/pci_iomap.h: make custom PCI BAR requirements explicit Date: Sun, 04 Oct 2015 21:02:04 +0200 Message-ID: <8902671.32Mbh7QhE4@wuerfel> In-Reply-To: <20151002235346.GJ14464@wotan.suse.de> References: <1440807447-584-1-git-send-email-mcgrof@do-not-panic.com> <1866509.8pE0MIz57e@wuerfel> <20151002235346.GJ14464@wotan.suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-arch-owner@vger.kernel.org List-ID: To: "Luis R. Rodriguez" Cc: "Luis R. Rodriguez" , linux-arch@vger.kernel.org, mingo@kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, linux-s390@vger.kernel.org, bp@suse.de, linux@roeck-us.net, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, rostedt@goodmis.org Message-ID: <20151004190204.jp4x4NRX1_BWiUHMlYbFIr01vOUjRUrXmKCqvRZ-i7w@z> On Saturday 03 October 2015 01:53:46 Luis R. Rodriguez wrote: > > > > Hmm, my gut feeling tells me that your approach won't solve the problem > > in general. s390 PCI is just weird in many ways and it will occasionally > > suffer from problems like this (as do other aspects of the s390 architecture > > that are unlike the rest of the world). > > > > Maybe Martin and Heiko can comment on this, they may have a preference > > from the s390 point of view. > > Hrm, so S390 is quirky is really odd ways that no other architecture is or > is at least for now not expected to be ? Absolutely correct. It is the only architecture I'm aware of that tries to support PCI that does not use pointer dereferences for MMIO. Arnd