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MdeModulePkg/PciHostBridge: Count the (mm)io overhead when polling

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RootBridgeIo.PollMem()/PollIo() originally don't count the IO/MMIO
access overhead when delaying.
The patch changes the implementation to count the access overhead
so that the actually delay equals to user required delay.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Cc: Chasel Chiu <chasel.chiu@intel.com>
This commit is contained in:
Ruiyu Ni
2018-04-23 14:20:26 +08:00
parent b22a62be5c
commit 0edb7ec5ce
5 changed files with 114 additions and 54 deletions
Download Patch File Download Diff File Expand all files Collapse all files

148
MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciRootBridgeIo.c
View File

@@ -2,7 +2,7 @@
PCI Root Bridge Io Protocol code.
Copyright (c) 1999 - 2017, Intel Corporation. All rights reserved.<BR>
Copyright (c) 1999 - 2018, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
@@ -468,6 +468,85 @@ RootBridgeIoGetMemTranslationByAddress (
return EFI_SUCCESS;
}
/**
Return the result of (Multiplicand * Multiplier / Divisor).
@param Multiplicand A 64-bit unsigned value.
@param Multiplier A 64-bit unsigned value.
@param Divisor A 32-bit unsigned value.
@param Remainder A pointer to a 32-bit unsigned value. This parameter is
optional and may be NULL.
@return Multiplicand * Multiplier / Divisor.
**/
UINT64
MultThenDivU64x64x32 (
IN UINT64 Multiplicand,
IN UINT64 Multiplier,
IN UINT32 Divisor,
OUT UINT32 *Remainder OPTIONAL
)
{
UINT64 Uint64;
UINT32 LocalRemainder;
UINT32 Uint32;
if (Multiplicand > DivU64x64Remainder (MAX_UINT64, Multiplier, NULL)) {
//
// Make sure Multiplicand is the bigger one.
//
if (Multiplicand < Multiplier) {
Uint64 = Multiplicand;
Multiplicand = Multiplier;
Multiplier = Uint64;
}
//
// Because Multiplicand * Multiplier overflows,
// Multiplicand * Multiplier / Divisor
// = (2 * Multiplicand' + 1) * Multiplier / Divisor
// = 2 * (Multiplicand' * Multiplier / Divisor) + Multiplier / Divisor
//
Uint64 = MultThenDivU64x64x32 (RShiftU64 (Multiplicand, 1), Multiplier, Divisor, &LocalRemainder);
Uint64 = LShiftU64 (Uint64, 1);
Uint32 = 0;
if ((Multiplicand & 0x1) == 1) {
Uint64 += DivU64x32Remainder (Multiplier, Divisor, &Uint32);
}
return Uint64 + DivU64x32Remainder (Uint32 + LShiftU64 (LocalRemainder, 1), Divisor, Remainder);
} else {
return DivU64x32Remainder (MultU64x64 (Multiplicand, Multiplier), Divisor, Remainder);
}
}
/**
Return the elapsed tick count from CurrentTick.
@param CurrentTick On input, the previous tick count.
On output, the current tick count.
@param StartTick The value the performance counter starts with when it
rolls over.
@param EndTick The value that the performance counter ends with before
it rolls over.
@return The elapsed tick count from CurrentTick.
**/
UINT64
GetElapsedTick (
UINT64 *CurrentTick,
UINT64 StartTick,
UINT64 EndTick
)
{
UINT64 PreviousTick;
PreviousTick = *CurrentTick;
*CurrentTick = GetPerformanceCounter();
if (StartTick < EndTick) {
return *CurrentTick - PreviousTick;
} else {
return PreviousTick - *CurrentTick;
}
}
/**
Polls an address in memory mapped I/O space until an exit condition is met,
or a timeout occurs.
@@ -517,6 +596,11 @@ RootBridgeIoPollMem (
EFI_STATUS Status;
UINT64 NumberOfTicks;
UINT32 Remainder;
UINT64 StartTick;
UINT64 EndTick;
UINT64 CurrentTick;
UINT64 ElapsedTick;
UINT64 Frequency;
if (Result == NULL) {
return EFI_INVALID_PARAMETER;
@@ -542,28 +626,18 @@ RootBridgeIoPollMem (
return EFI_SUCCESS;
} else {
//
// Determine the proper # of metronome ticks to wait for polling the
// location. The nuber of ticks is Roundup (Delay /
// mMetronome->TickPeriod)+1
// The "+1" to account for the possibility of the first tick being short
// because we started in the middle of a tick.
// NumberOfTicks = Frenquency * Delay / EFI_TIMER_PERIOD_SECONDS(1)
//
// BugBug: overriding mMetronome->TickPeriod with UINT32 until Metronome
// protocol definition is updated.
//
NumberOfTicks = DivU64x32Remainder (Delay, (UINT32) mMetronome->TickPeriod,
&Remainder);
if (Remainder != 0) {
NumberOfTicks += 1;
Frequency = GetPerformanceCounterProperties (&StartTick, &EndTick);
NumberOfTicks = MultThenDivU64x64x32 (Frequency, Delay, (UINT32)EFI_TIMER_PERIOD_SECONDS(1), &Remainder);
if (Remainder >= (UINTN)EFI_TIMER_PERIOD_SECONDS(1) / 2) {
NumberOfTicks++;
}
NumberOfTicks += 1;
while (NumberOfTicks != 0) {
mMetronome->WaitForTick (mMetronome, 1);
for ( ElapsedTick = 0, CurrentTick = GetPerformanceCounter()
; ElapsedTick <= NumberOfTicks
; ElapsedTick += GetElapsedTick (&CurrentTick, StartTick, EndTick)
) {
Status = This->Mem.Read (This, Width, Address, 1, Result);
if (EFI_ERROR (Status)) {
return Status;
@@ -572,8 +646,6 @@ RootBridgeIoPollMem (
if ((*Result & Mask) == Value) {
return EFI_SUCCESS;
}
NumberOfTicks -= 1;
}
}
return EFI_TIMEOUT;
@@ -626,6 +698,11 @@ RootBridgeIoPollIo (
EFI_STATUS Status;
UINT64 NumberOfTicks;
UINT32 Remainder;
UINT64 StartTick;
UINT64 EndTick;
UINT64 CurrentTick;
UINT64 ElapsedTick;
UINT64 Frequency;
//
// No matter what, always do a single poll.
@@ -651,25 +728,18 @@ RootBridgeIoPollIo (
return EFI_SUCCESS;
} else {
//
// Determine the proper # of metronome ticks to wait for polling the
// location. The number of ticks is Roundup (Delay /
// mMetronome->TickPeriod)+1
// The "+1" to account for the possibility of the first tick being short
// because we started in the middle of a tick.
// NumberOfTicks = Frenquency * Delay / EFI_TIMER_PERIOD_SECONDS(1)
//
NumberOfTicks = DivU64x32Remainder (Delay, (UINT32)mMetronome->TickPeriod,
&Remainder);
if (Remainder != 0) {
NumberOfTicks += 1;
Frequency = GetPerformanceCounterProperties (&StartTick, &EndTick);
NumberOfTicks = MultThenDivU64x64x32 (Frequency, Delay, (UINT32)EFI_TIMER_PERIOD_SECONDS(1), &Remainder);
if (Remainder >= (UINTN)EFI_TIMER_PERIOD_SECONDS(1) / 2) {
NumberOfTicks++;
}
NumberOfTicks += 1;
while (NumberOfTicks != 0) {
mMetronome->WaitForTick (mMetronome, 1);
for ( ElapsedTick = 0, CurrentTick = GetPerformanceCounter()
; ElapsedTick <= NumberOfTicks
; ElapsedTick += GetElapsedTick (&CurrentTick, StartTick, EndTick)
) {
Status = This->Io.Read (This, Width, Address, 1, Result);
if (EFI_ERROR (Status)) {
return Status;
@@ -678,8 +748,6 @@ RootBridgeIoPollIo (
if ((*Result & Mask) == Value) {
return EFI_SUCCESS;
}
NumberOfTicks -= 1;
}
}
return EFI_TIMEOUT;