Re: [patch] MdeModulePkg/XhciPei: 1ms delay before accessing MMIO reg in reset

["Zeng, Star" <star.zeng@intel.com>]

Reviewed-by: Star Zeng <star.zeng@intel.com>

-----Original Message-----
From: Tian, Feng 
Sent: Wednesday, September 14, 2016 9:49 AM
To: Zeng, Star <star.zeng@intel.com>
Cc: edk2-devel@lists.01.org
Subject: [patch] MdeModulePkg/XhciPei: 1ms delay before accessing MMIO reg in reset

Some XHCI HCs require to have 1ms delay before accessing any MMIO register in reset.

Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Feng Tian <feng.tian@intel.com>
---
 MdeModulePkg/Bus/Pci/XhciPei/XhcPeim.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MdeModulePkg/Bus/Pci/XhciPei/XhcPeim.c b/MdeModulePkg/Bus/Pci/XhciPei/XhcPeim.c
index a58739f..cd5c5cd 100644
--- a/MdeModulePkg/Bus/Pci/XhciPei/XhcPeim.c
+++ b/MdeModulePkg/Bus/Pci/XhciPei/XhcPeim.c
@@ -407,6 +407,7 @@ XhcPeiResetHC (
   }
 
   XhcPeiSetOpRegBit (Xhc, XHC_USBCMD_OFFSET, XHC_USBCMD_RESET);
+  MicroSecondDelay (1000);
   Status = XhcPeiWaitOpRegBit (Xhc, XHC_USBCMD_OFFSET, XHC_USBCMD_RESET, FALSE, Timeout);
 ON_EXIT:
   DEBUG ((EFI_D_INFO, "XhcPeiResetHC: %r\n", Status));
--
2.7.1.windows.2