MdeModulePkg/XhciDxe:1ms delay before access MMIO reg during reset

[mirror_edk2.git] / MdeModulePkg / Bus / Pci / XhciDxe / XhciReg.c

diff --git a/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c b/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c
index a66d7cd95b81829527d6d01b4af5f5418e1dc63e..0e1c86cc16f4b7f2464b3e2e69bc44842c353713 100644 (file)
--- a/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c
+++ b/MdeModulePkg/Bus/Pci/XhciDxe/XhciReg.c
@@ -2,7 +2,7 @@
 \r
   The XHCI register operation routines.\r
 \r
-Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2011 - 2016, Intel Corporation. All rights reserved.<BR>\r
 This program and the accompanying materials\r
 are licensed and made available under the terms and conditions of the BSD License\r
 which accompanies this distribution.  The full text of the license may be found at\r
@@ -515,16 +515,16 @@ XhcWaitOpRegBit (
   )\r
 {\r
   UINT32                  Index;\r
-  UINTN                   Loop;\r
+  UINT64                  Loop;\r
 \r
-  Loop   = (Timeout * XHC_1_MILLISECOND / XHC_POLL_DELAY) + 1;\r
+  Loop   = Timeout * XHC_1_MILLISECOND;\r
 \r
   for (Index = 0; Index < Loop; Index++) {\r
     if (XHC_REG_BIT_IS_SET (Xhc, Offset, Bit) == WaitToSet) {\r
       return EFI_SUCCESS;\r
     }\r
 \r
-    gBS->Stall (XHC_POLL_DELAY);\r
+    gBS->Stall (XHC_1_MICROSECOND);\r
   }\r
 \r
   return EFI_TIMEOUT;\r
@@ -687,6 +687,12 @@ XhcResetHC (
   if ((Xhc->DebugCapSupOffset == 0xFFFFFFFF) || ((XhcReadExtCapReg (Xhc, Xhc->DebugCapSupOffset) & 0xFF) != XHC_CAP_USB_DEBUG) ||\r
       ((XhcReadExtCapReg (Xhc, Xhc->DebugCapSupOffset + XHC_DC_DCCTRL) & BIT0) == 0)) {\r
     XhcSetOpRegBit (Xhc, XHC_USBCMD_OFFSET, XHC_USBCMD_RESET);\r
+    //\r
+    // Some XHCI host controllers require to have extra 1ms delay before accessing any MMIO register during reset.\r
+    // Otherwise there may have the timeout case happened.\r
+    // The below is a workaround to solve such problem.\r
+    //\r
+    gBS->Stall (XHC_1_MILLISECOND);\r
     Status = XhcWaitOpRegBit (Xhc, XHC_USBCMD_OFFSET, XHC_USBCMD_RESET, FALSE, Timeout);\r
   }\r
 \r