update comments

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9694 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
AJFISH 2010-01-08 21:03:12 +00:00
parent c22b6cdfa7
commit cc726b9ffd
1 changed files with 5 additions and 1 deletions

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@ -72,7 +72,11 @@ TimerInterruptHandler (
{
EFI_TPL OriginalTPL;
// Mask all interrupts
//
// DXE core uses this callback for the EFI timer tick. The DXE core uses locks
// that raise to TPL_HIGH and then restore back to current level. Thus we need
// to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
//
OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
MmioWrite32 (TIMER_CMD, 0);