From patchwork Mon Aug 20 13:46:31 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavin Shan X-Patchwork-Id: 178782 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C86BE2C0097 for ; Mon, 20 Aug 2012 23:47:08 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754233Ab2HTNrH (ORCPT ); Mon, 20 Aug 2012 09:47:07 -0400 Received: from e5.ny.us.ibm.com ([32.97.182.145]:50058 "EHLO e5.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754808Ab2HTNrG (ORCPT ); Mon, 20 Aug 2012 09:47:06 -0400 Received: from /spool/local by e5.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 20 Aug 2012 09:47:05 -0400 Received: from d01dlp02.pok.ibm.com (9.56.250.167) by e5.ny.us.ibm.com (192.168.1.105) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Mon, 20 Aug 2012 09:46:53 -0400 Received: from d01relay02.pok.ibm.com (d01relay02.pok.ibm.com [9.56.227.234]) by d01dlp02.pok.ibm.com (Postfix) with ESMTP id 2A1C96E8039 for ; Mon, 20 Aug 2012 09:46:53 -0400 (EDT) Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay02.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q7KDkqOs146038 for ; Mon, 20 Aug 2012 09:46:52 -0400 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q7KDkoTd016727 for ; Mon, 20 Aug 2012 09:46:51 -0400 Received: from shangw ([9.125.27.211]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id q7KDke7x015900; Mon, 20 Aug 2012 09:46:45 -0400 Received: by shangw (Postfix, from userid 1000) id 013D93022AE; Mon, 20 Aug 2012 21:46:41 +0800 (CST) From: Gavin Shan To: linux-pci@vger.kernel.org Cc: bhelgaas@google.com, benh@kernel.crashing.org, weiyang@linux.vnet.ibm.com, linuxram@us.ibm.com, yinghai@kernel.org, Gavin Shan Subject: [PATCH 4/8] pci: weak function returns alignment Date: Mon, 20 Aug 2012 21:46:31 +0800 Message-Id: <1345470395-17295-5-git-send-email-shangw@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1345470395-17295-1-git-send-email-shangw@linux.vnet.ibm.com> References: <1345470395-17295-1-git-send-email-shangw@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12082013-5930-0000-0000-00000B0EBFB8 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The patch implements the weak function to return the default I/O or memory alignment for P2P bridge. Currently, I/O window has 4KiB alignment and memory window is 4MiB aligned by default. On the other hand, those platforms (e.g. powernv) that have special requirements on the alignment could override the function by themselves. Signed-off-by: Gavin Shan --- drivers/pci/setup-bus.c | 24 ++++++++++++++++++++++++ include/linux/pci.h | 2 ++ 2 files changed, 26 insertions(+), 0 deletions(-) diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index fb50613..826a4f3 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -697,6 +697,30 @@ static resource_size_t calculate_memsize(resource_size_t size, return size; } +resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, + unsigned long type) +{ + return 1; +} + +#define PCI_P2P_DEFAULT_MEM_ALIGN 0x100000 /* 1MiB */ +#define PCI_P2P_DEFAULT_IO_ALIGN 0x1000 /* 4KiB */ + +static resource_size_t window_alignment(struct pci_bus *bus, + unsigned long type) +{ + resource_size_t align = 1, arch_align; + + if (type & IORESOURCE_MEM) + align = PCI_P2P_DEFAULT_MEM_ALIGN; + else if (type & IORESOURCE_IO) + align = PCI_P2P_DEFAULT_IO_ALIGN; + + arch_align = pcibios_window_alignment(bus, type); + + return max(align, arch_align); +} + /** * pbus_size_io() - size the io window of a given bus * diff --git a/include/linux/pci.h b/include/linux/pci.h index a47a4d3..739be31 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1034,6 +1034,8 @@ int pci_cfg_space_size_ext(struct pci_dev *dev); int pci_cfg_space_size(struct pci_dev *dev); unsigned char pci_bus_max_busnr(struct pci_bus *bus); void pci_setup_bridge(struct pci_bus *bus); +resource_size_t pcibios_window_alignment(struct pci_bus *bus, + unsigned long type); #define PCI_VGA_STATE_CHANGE_BRIDGE (1 << 0) #define PCI_VGA_STATE_CHANGE_DECODES (1 << 1)