From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com ([134.134.136.20]:44184 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753417Ab3EFSDf (ORCPT ); Mon, 6 May 2013 14:03:35 -0400 From: Jon Mason To: Bjorn Helgaas Cc: linux-pci@vger.kernel.org Subject: [PATCH] PCI: Workaround for NTB BAR size issue Date: Mon, 6 May 2013 11:03:33 -0700 Message-Id: <1367863413-30087-1-git-send-email-jon.mason@intel.com> Sender: linux-pci-owner@vger.kernel.org List-ID: Certain NTB devices have a hardware errata where, regardless of pre-configured value, reading the BAR size returns 4096. To work around this issue, add a PCI quirk to read the appropriate values from an alternative register in PCI config space and move the resource endpoints to the appropriate location. Signed-off-by: Jon Mason --- drivers/pci/quirks.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 7d68aee..a57a93b 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2865,6 +2865,30 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x65f9, quirk_intel_mc_errata); DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x65fa, quirk_intel_mc_errata); +/* Ivytown NTB BAR sizes are misreported by the hardware due to an errata. To + * work around this, query the size it should be configured to by the device and + * modify the resource end to correspond to this new size. + */ +static void quirk_intel_ntb(struct pci_dev *dev) +{ + int rc; + u8 val; + + rc = pci_read_config_byte(dev, 0x00D0, &val); + if (rc) + return; + + dev->resource[2].end = dev->resource[2].start + ((u64) 1 << val) - 1; + + rc = pci_read_config_byte(dev, 0x00D1, &val); + if (rc) + return; + + dev->resource[4].end = dev->resource[4].start + ((u64) 1 << val) - 1; +} +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0e08, quirk_intel_ntb); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0e0d, quirk_intel_ntb); + static ktime_t fixup_debug_start(struct pci_dev *dev, void (*fn)(struct pci_dev *dev)) { -- 1.7.9.5