release/4.8.25/PCI-Add-ACS-quirk-for-Intel-Union-Point.patch

From 8b4638e153e6aafc73d497869121961491a92a51 Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Thu, 19 Jan 2017 08:51:30 -0700
Subject: [PATCH] PCI: Add ACS quirk for Intel Union Point

commit 7184f5b451cf3dc61de79091d235b5d2bba2782d upstream.

Intel 200-series chipsets have the same errata as 100-series: the ACS
capability doesn't follow the PCIe spec, the capability and control
registers are dwords rather than words.  Add PCIe root port device IDs to
existing quirk.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 5e8abe005b29..12ab283cf7c9 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4140,15 +4140,35 @@ static int pci_quirk_intel_pch_acs(struct pci_dev *dev, u16 acs_flags)
  *
  * N.B. This doesn't fix what lspci shows.
  *
+ * The 100 series chipset specification update includes this as errata #23[3].
+ *
+ * The 200 series chipset (Union Point) has the same bug according to the
+ * specification update (Intel 200 Series Chipset Family Platform Controller
+ * Hub, Specification Update, January 2017, Revision 001, Document# 335194-001,
+ * Errata 22)[4].  Per the datasheet[5], root port PCI Device IDs for this
+ * chipset include:
+ *
+ * 0xa290-0xa29f PCI Express Root port #{0-16}
+ * 0xa2e7-0xa2ee PCI Express Root port #{17-24}
+ *
  * [1] http://www.intel.com/content/www/us/en/chipsets/100-series-chipset-datasheet-vol-2.html
  * [2] http://www.intel.com/content/www/us/en/chipsets/100-series-chipset-datasheet-vol-1.html
+ * [3] http://www.intel.com/content/www/us/en/chipsets/100-series-chipset-spec-update.html
+ * [4] http://www.intel.com/content/www/us/en/chipsets/200-series-chipset-pch-spec-update.html
+ * [5] http://www.intel.com/content/www/us/en/chipsets/200-series-chipset-pch-datasheet-vol-1.html
  */
 static bool pci_quirk_intel_spt_pch_acs_match(struct pci_dev *dev)
 {
-	return pci_is_pcie(dev) &&
-		pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT &&
-		((dev->device & ~0xf) == 0xa110 ||
-		 (dev->device >= 0xa167 && dev->device <= 0xa16a));
+	if (!pci_is_pcie(dev) || pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT)
+		return false;
+
+	switch (dev->device) {
+	case 0xa110 ... 0xa11f: case 0xa167 ... 0xa16a: /* Sunrise Point */
+	case 0xa290 ... 0xa29f: case 0xa2e7 ... 0xa2ee: /* Union Point */
+		return true;
+	}
+
+	return false;
 }
 
 #define INTEL_SPT_ACS_CTRL (PCI_ACS_CAP + 4)
-- 
2.12.0