OvmfPkg/ResetSystemLib: rename to BaseResetSystemLib

In preparation for introducing DxeResetSystemLib, rename the current
(only) ResetSystemLib instance to BaseResetSystemLib.

In the DSC files, keep the ResetSystemLib resolution in the same
[LibraryClasses] section, but move it near the TimerLib resolution, as the
differences between the ResetSystemLib instances will mostly follow those
seen under OvmfPkg/Library/AcpiTimerLib.

(While OvmfXen does not use "OvmfPkg/Library/AcpiTimerLib", perform the
same movement there too, for keeping future DSC diffing simple.)

Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Julien Grall <julien@xen.org>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Rebecca Cran <rebecca@bsdio.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=2675
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20200417153751.7110-6-lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@arm.com>
Reviewed-by: Rebecca Cran <rebecca@bsdio.com>

OvmfPkg/Library/ResetSystemLib/BaseResetShutdown.c

@@ -0,0 +1,51 @@
+/** @file
+  Base Reset System Library Shutdown API implementation for OVMF.
+
+  Copyright (C) 2020, Red Hat, Inc.
+  Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <Base.h>                   // BIT13
+
+#include <Library/BaseLib.h>        // CpuDeadLoop()
+#include <Library/DebugLib.h>       // ASSERT()
+#include <Library/IoLib.h>          // IoOr16()
+#include <Library/PciLib.h>         // PciRead16()
+#include <Library/ResetSystemLib.h> // ResetShutdown()
+#include <OvmfPlatforms.h>          // OVMF_HOSTBRIDGE_DID
+
+/**
+  Calling this function causes the system to enter a power state equivalent
+  to the ACPI G2/S5 or G3 states.
+
+  System shutdown should not return, if it returns, it means the system does
+  not support shut down reset.
+**/
+VOID
+EFIAPI
+ResetShutdown (
+  VOID
+  )
+{
+  UINT16 AcpiPmBaseAddress;
+  UINT16 HostBridgeDevId;
+
+  AcpiPmBaseAddress = 0;
+  HostBridgeDevId = PciRead16 (OVMF_HOSTBRIDGE_DID);
+  switch (HostBridgeDevId) {
+  case INTEL_82441_DEVICE_ID:
+    AcpiPmBaseAddress = PIIX4_PMBA_VALUE;
+    break;
+  case INTEL_Q35_MCH_DEVICE_ID:
+    AcpiPmBaseAddress = ICH9_PMBASE_VALUE;
+    break;
+  default:
+    ASSERT (FALSE);
+    CpuDeadLoop ();
+  }
+
+  IoBitFieldWrite16 (AcpiPmBaseAddress + 4, 10, 13, 0);
+  IoOr16 (AcpiPmBaseAddress + 4, BIT13);
+  CpuDeadLoop ();
+}