MdeModulePkg/Usb: Boost the r/w performance by reducing stall time on polling cmd...

[mirror_edk2.git] / MdeModulePkg / Bus / Pci / EhciPei / EhciSched.c

diff --git a/MdeModulePkg/Bus/Pci/EhciPei/EhciSched.c b/MdeModulePkg/Bus/Pci/EhciPei/EhciSched.c
index 1821a278da748225656db232a88e4d60b1598a9a..e992d4f287978fe5cb3af410d1782d0a43c610e6 100644 (file)
--- a/MdeModulePkg/Bus/Pci/EhciPei/EhciSched.c
+++ b/MdeModulePkg/Bus/Pci/EhciPei/EhciSched.c
@@ -2,7 +2,7 @@
 PEIM to produce gPeiUsb2HostControllerPpiGuid based on gPeiUsbControllerPpiGuid\r
 which is used to enable recovery function from USB Drivers.\r
 \r
-Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2010 - 2013, Intel Corporation. All rights reserved.<BR>\r
   \r
 This program and the accompanying materials\r
 are licensed and made available under the terms and conditions\r
@@ -425,19 +425,29 @@ EhcExecTransfer (
   UINTN                   Index;\r
   UINTN                   Loop;\r
   BOOLEAN                 Finished;\r
+  BOOLEAN                 InfiniteLoop;\r
 \r
   Status    = EFI_SUCCESS;\r
-  Loop      = (TimeOut * EHC_1_MILLISECOND / EHC_SYNC_POLL_INTERVAL) + 1;\r
-  Finished  = FALSE;\r
+  Loop      = TimeOut * EHC_1_MILLISECOND;\r
+  Finished     = FALSE;\r
+  InfiniteLoop = FALSE;\r
 \r
-  for (Index = 0; Index < Loop; Index++) {\r
+  //\r
+  // If Timeout is 0, then the caller must wait for the function to be completed\r
+  // until EFI_SUCCESS or EFI_DEVICE_ERROR is returned.\r
+  //\r
+  if (TimeOut == 0) {\r
+    InfiniteLoop = TRUE;\r
+  }\r
+\r
+  for (Index = 0; InfiniteLoop || (Index < Loop); Index++) {\r
     Finished = EhcCheckUrbResult (Ehc, Urb);\r
 \r
     if (Finished) {\r
       break;\r
     }\r
 \r
-    MicroSecondDelay (EHC_SYNC_POLL_INTERVAL);\r
+    MicroSecondDelay (EHC_1_MICROSECOND);\r
   }\r
 \r
   if (!Finished) {\r