PCI: Mark TI C667X to avoid bus reset

BugLink: https://bugs.launchpad.net/bugs/1934179
commit b5cf198e74a91073d12839a3e2db99994a39995d upstream.

Some TI KeyStone C667X devices do not support bus/hot reset.  The PCIESS
automatically disables LTSSM when Secondary Bus Reset is received and
device stops working.  Prevent bus reset for these devices.  With this
change, the device can be assigned to VMs with VFIO, but it will leak state
between VMs.

Reference: https://e2e.ti.com/support/processors/f/791/t/954382
Link: https://lore.kernel.org/r/20210315102606.17153-1-antti.jarvinen@gmail.com
Signed-off-by: Antti Järvinen <antti.jarvinen@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 862038155fdf5ad510d658d530f3e083b6cb87e8..01ec74d3d5d2e23c2f1727094f2fb14788114031 100644 (file)
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3592,6 +3592,16 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0034, quirk_no_bus_reset);
  */
 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CAVIUM, 0xa100, quirk_no_bus_reset);
 
+/*
+ * Some TI KeyStone C667X devices do not support bus/hot reset.  The PCIESS
+ * automatically disables LTSSM when Secondary Bus Reset is received and
+ * the device stops working.  Prevent bus reset for these devices.  With
+ * this change, the device can be assigned to VMs with VFIO, but it will
+ * leak state between VMs.  Reference
+ * https://e2e.ti.com/support/processors/f/791/t/954382
+ */
+DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_TI, 0xb005, quirk_no_bus_reset);
+
 static void quirk_no_pm_reset(struct pci_dev *dev)
 {
        /*