Commit 12b03188 authored by Jon Mason's avatar Jon Mason Committed by Bjorn Helgaas
Browse files

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: default avatarJon Mason <jon.mason@intel.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent f722406f

drivers/pci/quirks.c

+25 −0
Original line number Diff line number Diff line
@@ -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))

{