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| author | Gabriel Somlo <somlo@cmu.edu> | 2014-11-14 00:38:17 +0000 |
|---|---|---|
| committer | jljusten <jljusten@Edk2> | 2014-11-14 00:38:17 +0000 |
| commit | 170ef2d91612350fd1d1bac9d77b3ce0bffda714 (patch) | |
| tree | fa1e67115eefa994c76501526e67940dabc18f97 /OvmfPkg/Library/AcpiTimerLib/DxeAcpiTimerLib.c | |
| parent | 72a1100171a627ce26789c193ca7036eb8a5364a (diff) | |
| download | edk2-platforms-170ef2d91612350fd1d1bac9d77b3ce0bffda714.tar.xz | |
OvmfPkg: AcpiTimerLib: Split into multiple phase-specific instances
Remove local power management register access macros in favor of
factored-out ones in OvmfPkg/Include/OvmfPlatforms.h
Next, AcpiTimerLib is split out into three instances, for use during
various stages:
- BaseRom: used during SEC, PEI_CORE, and PEIM;
- Dxe: used during DXE_DRIVER and DXE_RUNTIME_DRIVER;
- Base: used by default during all other stages.
Most of the code remains in AcpiTimerLib.c, to be shared by all
instances. The two platform-dependent methods (constructor and
InternalAcpiGetTimerTick) are provided separately by source files
specific to each instance, namely [BaseRom|Base|Dxe]AcpiTimerLib.c.
Since pre-DXE stages can't rely on storing data in global variables,
methods specific to the "BaseRom" instance will call platform
detection macros each time they're invoked.
The "Base" instance calls platform detection macros only from its
constructor, and caches the address required by InternalAcpiTimerTick
in a global variable.
The "Dxe" instance is very similar to "Base", except no platform
detection macros are called at all; instead, the platform type is
read via a dynamic PCD set from PlatformPei.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16376 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'OvmfPkg/Library/AcpiTimerLib/DxeAcpiTimerLib.c')
| -rw-r--r-- | OvmfPkg/Library/AcpiTimerLib/DxeAcpiTimerLib.c | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/OvmfPkg/Library/AcpiTimerLib/DxeAcpiTimerLib.c b/OvmfPkg/Library/AcpiTimerLib/DxeAcpiTimerLib.c new file mode 100644 index 0000000000..2be0793057 --- /dev/null +++ b/OvmfPkg/Library/AcpiTimerLib/DxeAcpiTimerLib.c @@ -0,0 +1,99 @@ +/** @file
+ Provide constructor and GetTick for Dxe instance of ACPI Timer Library
+
+ Copyright (C) 2014, Gabriel L. Somlo <somlo@cmu.edu>
+
+ 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 http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+**/
+
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+#include <Library/PciLib.h>
+#include <OvmfPlatforms.h>
+
+//
+// Power Management PCI Configuration Register fields
+//
+#define PMBA_RTE BIT0
+
+//
+// Offset in the Power Management Base Address to the ACPI Timer
+//
+#define ACPI_TIMER_OFFSET 0x8
+
+//
+// Cached ACPI Timer IO Address
+//
+STATIC UINT32 mAcpiTimerIoAddr;
+
+/**
+ The constructor function caches the ACPI tick counter address
+
+ At the time this constructor runs (DXE_CORE or later), ACPI IO space
+ has already been enabled by either PlatformPei or by the "Base"
+ instance of this library.
+ In order to avoid querying the underlying platform type during each
+ tick counter read operation, we cache the counter address during
+ initialization of this instance of the Timer Library.
+
+ @retval EFI_SUCCESS The constructor always returns RETURN_SUCCESS.
+
+**/
+RETURN_STATUS
+EFIAPI
+AcpiTimerLibConstructor (
+ VOID
+ )
+{
+ UINT16 HostBridgeDevId;
+ UINTN Pmba;
+
+ //
+ // Query Host Bridge DID to determine platform type
+ //
+ HostBridgeDevId = PcdGet16 (PcdOvmfHostBridgePciDevId);
+ switch (HostBridgeDevId) {
+ case INTEL_82441_DEVICE_ID:
+ Pmba = POWER_MGMT_REGISTER_PIIX4 (0x40);
+ break;
+ case INTEL_Q35_MCH_DEVICE_ID:
+ Pmba = POWER_MGMT_REGISTER_Q35 (0x40);
+ break;
+ default:
+ DEBUG ((EFI_D_ERROR, "%a: Unknown Host Bridge Device ID: 0x%04x\n",
+ __FUNCTION__, HostBridgeDevId));
+ ASSERT (FALSE);
+ return RETURN_UNSUPPORTED;
+ }
+
+ mAcpiTimerIoAddr = (PciRead32 (Pmba) & ~PMBA_RTE) + ACPI_TIMER_OFFSET;
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Internal function to read the current tick counter of ACPI.
+
+ Read the current ACPI tick counter using the counter address cached
+ by this instance's constructor.
+
+ @return The tick counter read.
+
+**/
+UINT32
+InternalAcpiGetTimerTick (
+ VOID
+ )
+{
+ //
+ // Return the current ACPI timer value.
+ //
+ return IoRead32 (mAcpiTimerIoAddr);
+}
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