From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Petazzoni Subject: Re: [PATCHv3 1/3] ARM: mm: allow sub-architectures to override PCI I/O memory type Date: Thu, 15 May 2014 15:51:30 +0200 Message-ID: <20140515155130.193c3181@free-electrons.com> References: <1400145519-28530-1-git-send-email-thomas.petazzoni@free-electrons.com> <1400145519-28530-2-git-send-email-thomas.petazzoni@free-electrons.com> <8288032.jL4bOz6qPT@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <8288032.jL4bOz6qPT@wuerfel> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Arnd Bergmann Cc: linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Russell King , Will Deacon , Catalin Marinas , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Grant Likely , Rob Herring , Lior Amsalem , Andrew Lunn , Jason Cooper , Tawfik Bayouk , Nadav Haklai , Gregory Clement , Ezequiel Garcia , Albin Tonnerre , Sebastian Hesselbarth List-Id: devicetree@vger.kernel.org Dear Arnd Bergmann, On Thu, 15 May 2014 15:21:25 +0200, Arnd Bergmann wrote: > On Thursday 15 May 2014 11:18:37 Thomas Petazzoni wrote: > > @@ -445,7 +452,7 @@ int pci_ioremap_io(unsigned int offset, phys_addr_t phys_addr) > > return ioremap_page_range(PCI_IO_VIRT_BASE + offset, > > PCI_IO_VIRT_BASE + offset + SZ_64K, > > phys_addr, > > - __pgprot(get_mem_type(MT_DEVICE)->prot_pte)); > > + __pgprot(get_mem_type(pci_ioremap_mem_type)->prot_pte)); > > } > > EXPORT_SYMBOL_GPL(pci_ioremap_io); > > > > As discussed on IRC, I think we'd be better off making this a strong-ordered > mapping for all platforms unconditionally. The PCI I/O space semantics > require non-posted writes, which is the main difference between device > and SO mappings, so the same fix is required both for mvebu as a workaround > for the deadlock as well as for everyone else as a fix for an incorrect > PCI behavior. Ok, I'll take that into account when posting a v4. Thanks for the reminder, Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html