From 12b03188ab2afed784e416b4fb1366b4a6915ac0 Mon Sep 17 00:00:00 2001 From: Jon Mason Date: Mon, 6 May 2013 08:03:33 +0000 Subject: [PATCH] PCI: Work around Ivytown NTB BAR size issue Certain NTB devices have a hardware erratum 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 Signed-off-by: Bjorn Helgaas --- drivers/pci/quirks.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 7d68aeebf56b..7f492574dcf4 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2865,6 +2865,31 @@ 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 erratum. 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)) { -- 2.30.2