[Qemu-stable] [PATCH 04/88] xhci PCIe endpoint migration compatibility fix

[Michael Roth]

From: "Dr. David Alan Gilbert" <address@hidden>

Add back the PCIe config capabilities on XHCI cards in non-PCIe slots,
but only for machine types before 2.1.

This fixes a migration incompatibility in the XHCI PCI devices
caused by:
   058fdcf52cdbf57b67e7 - xhci: add endpoint cap on express bus only

Note that in fixing it for compatibility with older QEMUs, it breaks
compatibility with existing QEMU 2.1's on older machine types.

The status before this patch was (if it used an XHCI adapter):
   machine type | source qemu
     any           pre-2.1     - FAIL
     any           2.1...      - PASS

With this patch:
   machine type | source qemu
     any           pre-2.1    - PASS
     pre-2.1       2.1...     - FAIL
     2.1           2.1...     - PASS

A test to trigger it is to add '-device nec-usb-xhci,id=xhci,addr=0x12'
to the command line.

Cc: address@hidden
Signed-off-by: Dr. David Alan Gilbert <address@hidden>
Acked-by: Michael S. Tsirkin <address@hidden>
Signed-off-by: Gerd Hoffmann <address@hidden>
(cherry picked from commit e6043e92c2812a56b8f6cf35d5512067c746ce21)
Signed-off-by: Michael Roth <address@hidden>
---
 hw/usb/hcd-xhci.c    | 6 +++++-
 include/hw/i386/pc.h | 5 +++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/hw/usb/hcd-xhci.c b/hw/usb/hcd-xhci.c
index 58c4b11..807e1ae 100644
--- a/hw/usb/hcd-xhci.c
+++ b/hw/usb/hcd-xhci.c
@@ -499,6 +499,7 @@ enum xhci_flags {
     XHCI_FLAG_USE_MSI = 1,
     XHCI_FLAG_USE_MSI_X,
     XHCI_FLAG_SS_FIRST,
+    XHCI_FLAG_FORCE_PCIE_ENDCAP,
 };
 
 static void xhci_kick_ep(XHCIState *xhci, unsigned int slotid,
@@ -3626,7 +3627,8 @@ static int usb_xhci_initfn(struct PCIDevice *dev)
                      
PCI_BASE_ADDRESS_SPACE_MEMORY|PCI_BASE_ADDRESS_MEM_TYPE_64,
                      &xhci->mem);
 
-    if (pci_bus_is_express(dev->bus)) {
+    if (pci_bus_is_express(dev->bus) ||
+        xhci_get_flag(xhci, XHCI_FLAG_FORCE_PCIE_ENDCAP)) {
         ret = pcie_endpoint_cap_init(dev, 0xa0);
         assert(ret >= 0);
     }
@@ -3818,6 +3820,8 @@ static Property xhci_properties[] = {
     DEFINE_PROP_BIT("msix",     XHCIState, flags, XHCI_FLAG_USE_MSI_X, true),
     DEFINE_PROP_BIT("superspeed-ports-first",
                     XHCIState, flags, XHCI_FLAG_SS_FIRST, true),
+    DEFINE_PROP_BIT("force-pcie-endcap", XHCIState, flags,
+                    XHCI_FLAG_FORCE_PCIE_ENDCAP, false),
     DEFINE_PROP_UINT32("intrs", XHCIState, numintrs, MAXINTRS),
     DEFINE_PROP_UINT32("slots", XHCIState, numslots, MAXSLOTS),
     DEFINE_PROP_UINT32("p2",    XHCIState, numports_2, 4),
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index 5f0a265..b558875 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -318,6 +318,11 @@ bool e820_get_entry(int, uint32_t, uint64_t *, uint64_t *);
             .value    = "off",\
         },\
         {\
+            .driver   = "nec-usb-xhci",\
+            .property = "force-pcie-endcap",\
+            .value    = "on",\
+        },\
+        {\
             .driver   = "pci-serial",\
             .property = "prog_if",\
             .value    = stringify(0),\
-- 
1.9.1