From b6a8c4f1ada2c7d31bdd2438163f11026a0a0711 Mon Sep 17 00:00:00 2001
From: Alex Williamson <alex.williamson@redhat.com>
Date: Fri, 17 Jul 2015 20:46:43 +0200
Subject: [PATCH 2/5] vfio/pci : Add pba_offset PCI quirk for Chelsio T5
 devices

Message-id: <20150717203953.606.815.stgit@gimli.home>
Patchwork-id: 67057
O-Subject: [RHEL7.2 qemu-kvm PATCH] vfio/pci : Add pba_offset PCI quirk for Chelsio T5 devices
Bugzilla: 1244347
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Bandan Das <bsd@redhat.com>
RH-Acked-by: Laszlo Ersek <lersek@redhat.com>

From: Gabriel Laupre <glaupre@chelsio.com>

Upstream: 43302969966bc3a95470bfc300289a83068ef5d9

Fix pba_offset initialization value for Chelsio T5 Virtual Function
device. The T5 hardware has a bug in it where it reports a Pending Interrupt
Bit Array Offset of 0x8000 for its SR-IOV Virtual Functions instead
of the 0x1000 that the hardware actually uses internally. As the hardware
doesn't return the correct pba_offset value, add a quirk to instead
return a hardcoded value of 0x1000 when a Chelsio T5 VF device is
detected.

This bug has been fixed in the Chelsio's next chip series T6 but there are
no plans to respin the T5 ASIC for this bug. It is just documented in the
T5 Errata and left it at that.

Signed-off-by: Gabriel Laupre <glaupre@chelsio.com>
Reviewed-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
 hw/misc/vfio.c           | 27 +++++++++++++++++++++++++++
 include/hw/pci/pci_ids.h |  2 ++
 2 files changed, 29 insertions(+)

diff --git a/hw/misc/vfio.c b/hw/misc/vfio.c
index 118489c..36b9832 100644
--- a/hw/misc/vfio.c
+++ b/hw/misc/vfio.c
@@ -2466,6 +2466,33 @@ static int vfio_early_setup_msix(VFIODevice *vdev)
             vdev->host.function, pos, vdev->msix->table_bar,
             vdev->msix->table_offset, vdev->msix->entries);
 
+    /*
+     * Test the size of the pba_offset variable and catch if it extends outside
+     * of the specified BAR. If it is the case, we need to apply a hardware
+     * specific quirk if the device is known or we have a broken configuration.
+     */
+    if (vdev->msix->pba_offset >=
+        vdev->bars[vdev->msix->pba_bar].size) {
+
+        PCIDevice *pdev = &vdev->pdev;
+        uint16_t vendor = pci_get_word(pdev->config + PCI_VENDOR_ID);
+        uint16_t device = pci_get_word(pdev->config + PCI_DEVICE_ID);
+
+        /*
+         * Chelsio T5 Virtual Function devices are encoded as 0x58xx for T5
+         * adapters. The T5 hardware returns an incorrect value of 0x8000 for
+         * the VF PBA offset while the BAR itself is only 8k. The correct value
+         * is 0x1000, so we hard code that here.
+         */
+        if (vendor == PCI_VENDOR_ID_CHELSIO && (device & 0xff00) == 0x5800) {
+            vdev->msix->pba_offset = 0x1000;
+        } else {
+            error_report("vfio: Hardware reports invalid configuration, "
+                         "MSIX PBA outside of specified BAR");
+            return -EINVAL;
+        }
+    }
+
     return 0;
 }
 
diff --git a/include/hw/pci/pci_ids.h b/include/hw/pci/pci_ids.h
index d8dc2f1..3792255 100644
--- a/include/hw/pci/pci_ids.h
+++ b/include/hw/pci/pci_ids.h
@@ -102,6 +102,8 @@
 #define PCI_VENDOR_ID_ENSONIQ            0x1274
 #define PCI_DEVICE_ID_ENSONIQ_ES1370     0x5000
 
+#define PCI_VENDOR_ID_CHELSIO            0x1425
+
 #define PCI_VENDOR_ID_FREESCALE          0x1957
 #define PCI_DEVICE_ID_MPC8533E           0x0030
 
-- 
1.8.3.1