[PATCH v2] PCI: Add quirk for VCA NTB

["Kitszel, PrzemyslawX" <przemyslawx.kitszel@intel.com>]

From 8ec717d913bba70e3e0dd783eebf355e0d64a159 Mon Sep 17 00:00:00 2001
From: Slawomir Pawlowski <slawomir.pawlowski@intel.com>
Date: Fri, 21 Sep 2018 15:55:12 +0200
Subject: [PATCH v2] PCI: Add quirk for VCA NTB

Intel Visual Compute Accelerator (VCA) is a family of PCIe add-in devices
exposing computational units via Non Transparent Bridges (NTB, PEX 87xx).

Similarly to MIC x200, there is need to add DMA aliases to allow buffer
access when IOMMU is enabled.
Following aliases are allowing host device and computational unit to access
each other.
Together those aliases marks whole VCA device as one IOMMU group.

All possible slot numbers (0x20) are used, since we are unable to tell what
slot is used on other side.
This quirk is intended for both host and computational unit sides.
The VCA devices have up to 5 functions - 4 for DMA channels and one
additional.

Signed-off-by: Slawomir Pawlowski <slawomir.pawlowski@intel.com>
Signed-off-by: Przemek Kitszel <przemyslawx.kitszel@intel.com>
---
Changes in v2:
  - fix typos: s/sine/since/g

 drivers/pci/quirks.c | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index ded60757a573..921a080146f3 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -4062,6 +4062,38 @@ static void quirk_mic_x200_dma_alias(struct pci_dev *pdev)
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2260, quirk_mic_x200_dma_alias);
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2264, quirk_mic_x200_dma_alias);
 
+/*
+ * Intel Visual Compute Accelerator (VCA) is a family of PCIe add-in devices
+ * exposing computational units via Non Transparent Bridges (NTB, PEX 87xx).
+ * Similarly to MIC x200, there is need to add DMA aliases to allow buffer
+ * access when IOMMU is enabled.
+ * Following aliases are allowing host device and computational unit to access
+ * each other. Together those aliases marks whole VCA device as one IOMMU group.
+ * All possible slot numbers (0x20) are used, since we are unable to tell what
+ * slot is used on other side.
+ * This quirk is intended for both host and computational unit sides.
+ * The VCA devices have up to 5 functions (4 for DMA channels and 1 additional).
+ */
+static void quirk_pex_vca_alias(struct pci_dev *pdev)
+{
+	const unsigned int num_pci_slots = 0x20;
+	unsigned int slot;
+
+	for (slot = 0; slot < num_pci_slots; slot++) {
+		pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x0));
+		pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x1));
+		pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x2));
+		pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x3));
+		pci_add_dma_alias(pdev, PCI_DEVFN(slot, 0x4));
+	}
+}
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2954, quirk_pex_vca_alias);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2955, quirk_pex_vca_alias);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2956, quirk_pex_vca_alias);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2958, quirk_pex_vca_alias);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2959, quirk_pex_vca_alias);
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x295A, quirk_pex_vca_alias);
+
 /*
  * The IOMMU and interrupt controller on Broadcom Vulcan/Cavium ThunderX2 are
  * associated not at the root bus, but at a bridge below. This quirk avoids
-- 
2.22.0