Fix the hardware flow control logic in SerialIo driver.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@10228 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/IntelFrameworkModulePkg/Bus/Isa/IsaSerialDxe/Serial.c b/IntelFrameworkModulePkg/Bus/Isa/IsaSerialDxe/Serial.c
index 03dae25b2d5ad958312609c17e97197a49d5ad43..04d6373592d41393bb9555d195baa0cc4860bc66 100644 (file)
--- a/IntelFrameworkModulePkg/Bus/Isa/IsaSerialDxe/Serial.c
+++ b/IntelFrameworkModulePkg/Bus/Isa/IsaSerialDxe/Serial.c
@@ -909,7 +909,7 @@ IsaSerialReceiveTransmit (
           //\r
           TimeOut   = 0;\r
           Msr.Data  = READ_MSR (SerialDevice->IsaIo, SerialDevice->BaseAddress);\r
-          while ((Msr.Bits.Dcd == 1) && ((Msr.Bits.Cts == 0) || FeaturePcdGet(PcdIsaBusSerialUseHalfHandshake))) {\r
+          while ((Msr.Bits.Dcd == 1) && ((Msr.Bits.Cts == 0) ^ FeaturePcdGet(PcdIsaBusSerialUseHalfHandshake))) {\r
             gBS->Stall (TIMEOUT_STALL_INTERVAL);\r
             TimeOut++;\r
             if (TimeOut > 5) {\r
@@ -919,7 +919,7 @@ IsaSerialReceiveTransmit (
             Msr.Data = READ_MSR (SerialDevice->IsaIo, SerialDevice->BaseAddress);\r
           }\r
 \r
-          if ((Msr.Bits.Dcd == 0) && ((Msr.Bits.Cts == 1) || FeaturePcdGet(PcdIsaBusSerialUseHalfHandshake))) {\r
+          if ((Msr.Bits.Dcd == 0) || ((Msr.Bits.Cts == 1) ^ FeaturePcdGet(PcdIsaBusSerialUseHalfHandshake))) {\r
             IsaSerialFifoRemove (&SerialDevice->Transmit, &Data);\r
             WRITE_THR (SerialDevice->IsaIo, SerialDevice->BaseAddress, Data);\r
           }\r