[PATCH 1/4] MdeModulePkg/XhciDxe/XhciReg: Handle incorrect PSIV indices

["Sean Rhodes" <sean@starlabs.systems>]

From: Matt DeVillier <matt.devillier@gmail.com>

On some platforms, including Sky Lake and Kaby Lake, the PSIV (Protocol
Speed ID Value) indices are shared between Protocol Speed ID DWORD' in
the extended capabilities registers for both USB2 (Full Speed) and USB3
(Super Speed).

An example can be found below:

    XhcCheckUsbPortSpeedUsedPsic: checking for USB2 ext caps
    XhciPsivGetPsid: found 3 PSID entries
    XhciPsivGetPsid: looking for port speed 1
    XhciPsivGetPsid: PSIV 1 PSIE 2 PLT 0 PSIM 12
    XhciPsivGetPsid: PSIV 2 PSIE 1 PLT 0 PSIM 1500
    XhciPsivGetPsid: PSIV 3 PSIE 2 PLT 0 PSIM 480
    XhcCheckUsbPortSpeedUsedPsic: checking for USB3 ext caps
    XhciPsivGetPsid: found 3 PSID entries
    XhciPsivGetPsid: looking for port speed 1
    XhciPsivGetPsid: PSIV 1 PSIE 3 PLT 0 PSIM 5
    XhciPsivGetPsid: PSIV 2 PSIE 3 PLT 0 PSIM 10
    XhciPsivGetPsid: PSIV 34 PSIE 2 PLT 0 PSIM 1248

The result is edk2 detecting USB2 devices as USB3 devices, which
consequently causes enumeration to fail.

To avoid incorrect detection, check the extended capability registers
for USB2 before USB3. If edk2 finds a match for a USB 2 device, don't
check for USB 3.

Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Reviewed-by: Sean Rhodes <sean@starlabs.systems>
Signed-off-by: Matt DeVillier <matt.devillier@gmail.com>
Change-Id: I5bcf32105ce85fda95b4ba98a5e420e8f522374c
---
 MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c | 36 +++++++++++++++-----------
 MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.h |  1 +
 2 files changed, 22 insertions(+), 15 deletions(-)

diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c b/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c
index 2b4a4b2444..c992323443 100644
--- a/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c
+++ b/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c
@@ -698,25 +698,11 @@ XhcCheckUsbPortSpeedUsedPsic (
   SpField.Dword = 0;
   UsbSpeedIdMap = 0;
 
-  //
-  // Check xHCI Supported Protocol Capability, find the PSIV field to match
-  // PortSpeed definition when the Major Revision is 03h.
-  //
-  if (Xhc->Usb3SupOffset != 0xFFFFFFFF) {
-    SpField.Dword = XhciPsivGetPsid (Xhc, Xhc->Usb3SupOffset, PortSpeed);
-    if (SpField.Dword != 0) {
-      //
-      // Found the corresponding PORTSC value in PSIV field of USB3 offset.
-      //
-      UsbSpeedIdMap = USB_PORT_STAT_SUPER_SPEED;
-    }
-  }
-
   //
   // Check xHCI Supported Protocol Capability, find the PSIV field to match
   // PortSpeed definition when the Major Revision is 02h.
   //
-  if ((UsbSpeedIdMap == 0) && (Xhc->Usb2SupOffset != 0xFFFFFFFF)) {
+  if (Xhc->Usb2SupOffset != 0xFFFFFFFF) {
     SpField.Dword = XhciPsivGetPsid (Xhc, Xhc->Usb2SupOffset, PortSpeed);
     if (SpField.Dword != 0) {
       //
@@ -733,6 +719,12 @@ XhcCheckUsbPortSpeedUsedPsic (
           // PSIM shows as default High-speed protocol, apply to High-speed mapping
           //
           UsbSpeedIdMap = USB_PORT_STAT_HIGH_SPEED;
+        } else if (SpField.Data.Psim == XHC_SUPPORTED_PROTOCOL_USB2_FULL_SPEED_PSIM) {
+          //
+          // PSIM shows as default Full-speed protocol, return 0
+          // to ensure no port status set
+          //
+          return 0;
         }
       } else if (SpField.Data.Psie == 1) {
         //
@@ -750,6 +742,20 @@ XhcCheckUsbPortSpeedUsedPsic (
     }
   }
 
+  //
+  // Check xHCI Supported Protocol Capability, find the PSIV field to match
+  // PortSpeed definition when the Major Revision is 03h.
+  //
+  if ((UsbSpeedIdMap == 0) && (Xhc->Usb3SupOffset != 0xFFFFFFFF)) {
+    SpField.Dword = XhciPsivGetPsid (Xhc, Xhc->Usb3SupOffset, PortSpeed);
+    if (SpField.Dword != 0) {
+      //
+      // Found the corresponding PORTSC value in PSIV field of USB3 offset.
+      //
+      UsbSpeedIdMap = USB_PORT_STAT_SUPER_SPEED;
+    }
+  }
+
   return UsbSpeedIdMap;
 }
 
diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.h b/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.h
index 5fe2ba4f0e..74ac6297ba 100644
--- a/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.h
+++ b/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.h
@@ -85,6 +85,7 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #define XHC_SUPPORTED_PROTOCOL_DW2_OFFSET               0x08
 #define XHC_SUPPORTED_PROTOCOL_PSI_OFFSET               0x10
 #define XHC_SUPPORTED_PROTOCOL_USB2_HIGH_SPEED_PSIM     480
+#define XHC_SUPPORTED_PROTOCOL_USB2_FULL_SPEED_PSIM     12
 #define XHC_SUPPORTED_PROTOCOL_USB2_LOW_SPEED_PSIM      1500
 
 #pragma pack (1)
-- 
2.37.2