Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753956AbaLOPIA (ORCPT ); Mon, 15 Dec 2014 10:08:00 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:38405 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752528AbaLOO1m (ORCPT ); Mon, 15 Dec 2014 09:27:42 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Yinghai Lu , Bjorn Helgaas , Luis Henriques Subject: [PATCH 3.16.y-ckt 046/168] PCI: Support 64-bit bridge windows if we have 64-bit dma_addr_t Date: Mon, 15 Dec 2014 14:25:00 +0000 Message-Id: <1418653622-21105-47-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.3 In-Reply-To: <1418653622-21105-1-git-send-email-luis.henriques@canonical.com> References: <1418653622-21105-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt3 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Yinghai Lu commit 7fc986d8a9727e5d40da3c2c1c343da6142e82a9 upstream. Aaron reported that a 32-bit x86 kernel with Physical Address Extension (PAE) support complains about bridge prefetchable memory windows above 4GB: pci_bus 0000:00: root bus resource [mem 0x380000000000-0x383fffffffff] ... pci 0000:03:00.0: reg 0x10: [mem 0x383fffc00000-0x383fffdfffff 64bit pref] pci 0000:03:00.0: reg 0x20: [mem 0x383fffe04000-0x383fffe07fff 64bit pref] pci 0000:03:00.1: reg 0x10: [mem 0x383fffa00000-0x383fffbfffff 64bit pref] pci 0000:03:00.1: reg 0x20: [mem 0x383fffe00000-0x383fffe03fff 64bit pref] pci 0000:00:02.2: PCI bridge to [bus 03-04] pci 0000:00:02.2: bridge window [io 0x1000-0x1fff] pci 0000:00:02.2: bridge window [mem 0x91900000-0x91cfffff] pci 0000:00:02.2: can't handle 64-bit address space for bridge In this kernel, unsigned long is 32 bits and dma_addr_t is 64 bits. Previously we used "unsigned long" to hold the bridge window address. But this is a bus address, so we should use dma_addr_t instead. Use dma_addr_t to hold the bridge window base and limit. The question of whether the CPU can actually *address* the window is separate and depends on what the physical address space of the CPU is and whether the host bridge does any address translation. [bhelgaas: fix "shift count > width of type", changelog, stable tag] Fixes: d56dbf5bab8c ("PCI: Allocate 64-bit BARs above 4G when possible") Link: https://bugzilla.kernel.org/show_bug.cgi?id=88131 Reported-by: Aaron Ma Tested-by: Aaron Ma Signed-off-by: Yinghai Lu Signed-off-by: Bjorn Helgaas Signed-off-by: Luis Henriques --- drivers/pci/probe.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 4170113cde61..9cce960029aa 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -406,15 +406,16 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child) { struct pci_dev *dev = child->self; u16 mem_base_lo, mem_limit_lo; - unsigned long base, limit; + u64 base64, limit64; + dma_addr_t base, limit; struct pci_bus_region region; struct resource *res; res = child->resource[2]; pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo); pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo); - base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16; - limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16; + base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16; + limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16; if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) { u32 mem_base_hi, mem_limit_hi; @@ -428,17 +429,20 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child) * this, just assume they are not being used. */ if (mem_base_hi <= mem_limit_hi) { -#if BITS_PER_LONG == 64 - base |= ((unsigned long) mem_base_hi) << 32; - limit |= ((unsigned long) mem_limit_hi) << 32; -#else - if (mem_base_hi || mem_limit_hi) { - dev_err(&dev->dev, "can't handle 64-bit address space for bridge\n"); - return; - } -#endif + base64 |= (u64) mem_base_hi << 32; + limit64 |= (u64) mem_limit_hi << 32; } } + + base = (dma_addr_t) base64; + limit = (dma_addr_t) limit64; + + if (base != base64) { + dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n", + (unsigned long long) base64); + return; + } + if (base <= limit) { res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH; -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/