[PATCH v4 04/11] ArmVirtPkg: implement ArmVirtPsciResetSystemPeiLib

["Ard Biesheuvel" <ard.biesheuvel@linaro.org>]

Implement a ArmVirtPkg specific version of the PSCI ResetSystemLib that
is usable in the PEI phase, as the existing one relies on the FDT client
protocol, making it unsuitable.

Note that accessing the device tree passed by QEMU via its initial base
address is guaranteed to be safe at any time during the PEI phase, so we
can defer discovery of the PSCI method until the time the reset library
is actually invoked (which is rarely)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Laszlo Ersek <lersek@redhat.com>
---
 ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.c   | 232 ++++++++++++++++++++
 ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.inf |  39 ++++
 2 files changed, 271 insertions(+)

diff --git a/ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.c b/ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.c
new file mode 100644
index 000000000000..394a04e3c384
--- /dev/null
+++ b/ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.c
@@ -0,0 +1,232 @@
+/** @file
+  Reset System lib using PSCI hypervisor or secure monitor calls
+
+  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
+  Copyright (c) 2013, ARM Ltd. All rights reserved.<BR>
+  Copyright (c) 2014-2020, Linaro Ltd. All rights reserved.<BR>
+  Copyright (c) 2019, Intel Corporation. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <PiPei.h>
+
+#include <libfdt.h>
+#include <Library/ArmHvcLib.h>
+#include <Library/ArmSmcLib.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/HobLib.h>
+#include <Library/ResetSystemLib.h>
+
+#include <IndustryStandard/ArmStdSmc.h>
+
+typedef enum {
+  PsciMethodUnknown,
+  PsciMethodSmc,
+  PsciMethodHvc,
+} PSCI_METHOD;
+
+STATIC
+PSCI_METHOD
+DiscoverPsciMethod (
+  VOID
+  )
+{
+  VOID                            *DeviceTreeBase;
+  INT32                           Node, Prev;
+  INT32                           Len;
+  CONST CHAR8                     *Compatible;
+  CONST CHAR8                     *CompatibleItem;
+  CONST VOID                      *Prop;
+
+  DeviceTreeBase = (VOID*)(UINTN)PcdGet64 (PcdDeviceTreeInitialBaseAddress);
+  ASSERT (fdt_check_header (DeviceTreeBase) == 0);
+
+  //
+  // Enumerate all FDT nodes looking for the PSCI node and capture the method
+  //
+  for (Prev = 0;; Prev = Node) {
+    Node = fdt_next_node (DeviceTreeBase, Prev, NULL);
+    if (Node < 0) {
+      break;
+    }
+
+    Compatible = fdt_getprop (DeviceTreeBase, Node, "compatible", &Len);
+    if (Compatible == NULL) {
+      continue;
+    }
+
+    //
+    // Iterate over the NULL-separated items in the compatible string
+    //
+    for (CompatibleItem = Compatible; CompatibleItem < Compatible + Len;
+      CompatibleItem += 1 + AsciiStrLen (CompatibleItem)) {
+
+      if (AsciiStrCmp (CompatibleItem, "arm,psci-0.2") != 0) {
+        continue;
+      }
+
+      Prop = fdt_getprop (DeviceTreeBase, Node, "method", NULL);
+      if (!Prop) {
+        DEBUG ((DEBUG_ERROR, "%a: Missing PSCI method property\n",
+          __FUNCTION__));
+        return PsciMethodUnknown;
+      }
+
+      if (AsciiStrnCmp (Prop, "hvc", 3) == 0) {
+        return PsciMethodHvc;
+      } else if (AsciiStrnCmp (Prop, "smc", 3) == 0) {
+        return PsciMethodSmc;
+      } else {
+        DEBUG ((DEBUG_ERROR, "%a: Unknown PSCI method \"%a\"\n", __FUNCTION__,
+          Prop));
+        return PsciMethodUnknown;
+      }
+    }
+  }
+  return PsciMethodUnknown;
+}
+
+STATIC
+VOID
+PerformPsciAction (
+  IN  UINTN     Arg0
+  )
+{
+  ARM_SMC_ARGS ArmSmcArgs;
+  ARM_HVC_ARGS ArmHvcArgs;
+
+  ArmSmcArgs.Arg0 = Arg0;
+  ArmHvcArgs.Arg0 = Arg0;
+
+  switch (DiscoverPsciMethod ()) {
+  case PsciMethodHvc:
+    ArmCallHvc (&ArmHvcArgs);
+    break;
+
+  case PsciMethodSmc:
+    ArmCallSmc (&ArmSmcArgs);
+    break;
+
+  default:
+    DEBUG ((DEBUG_ERROR, "%a: no PSCI method defined\n", __FUNCTION__));
+    ASSERT (FALSE);
+  }
+}
+
+/**
+  This function causes a system-wide reset (cold reset), in which
+  all circuitry within the system returns to its initial state. This type of reset
+  is asynchronous to system operation and operates without regard to
+  cycle boundaries.
+
+  If this function returns, it means that the system does not support cold reset.
+**/
+VOID
+EFIAPI
+ResetCold (
+  VOID
+  )
+{
+  // Send a PSCI 0.2 SYSTEM_RESET command
+  PerformPsciAction (ARM_SMC_ID_PSCI_SYSTEM_RESET);
+}
+
+/**
+  This function causes a system-wide initialization (warm reset), in which all processors
+  are set to their initial state. Pending cycles are not corrupted.
+
+  If this function returns, it means that the system does not support warm reset.
+**/
+VOID
+EFIAPI
+ResetWarm (
+  VOID
+  )
+{
+  // Map a warm reset into a cold reset
+  ResetCold ();
+}
+
+/**
+  This function causes the system to enter a power state equivalent
+  to the ACPI G2/S5 or G3 states.
+
+  If this function returns, it means that the system does not support shutdown reset.
+**/
+VOID
+EFIAPI
+ResetShutdown (
+  VOID
+  )
+{
+  // Send a PSCI 0.2 SYSTEM_OFF command
+  PerformPsciAction (ARM_SMC_ID_PSCI_SYSTEM_OFF);
+}
+
+/**
+  This function causes a systemwide reset. The exact type of the reset is
+  defined by the EFI_GUID that follows the Null-terminated Unicode string passed
+  into ResetData. If the platform does not recognize the EFI_GUID in ResetData
+  the platform must pick a supported reset type to perform.The platform may
+  optionally log the parameters from any non-normal reset that occurs.
+
+  @param[in]  DataSize   The size, in bytes, of ResetData.
+  @param[in]  ResetData  The data buffer starts with a Null-terminated string,
+                         followed by the EFI_GUID.
+**/
+VOID
+EFIAPI
+ResetPlatformSpecific (
+  IN UINTN   DataSize,
+  IN VOID    *ResetData
+  )
+{
+  // Map the platform specific reset as reboot
+  ResetCold ();
+}
+
+/**
+  The ResetSystem function resets the entire platform.
+
+  @param[in] ResetType      The type of reset to perform.
+  @param[in] ResetStatus    The status code for the reset.
+  @param[in] DataSize       The size, in bytes, of ResetData.
+  @param[in] ResetData      For a ResetType of EfiResetCold, EfiResetWarm, or EfiResetShutdown
+                            the data buffer starts with a Null-terminated string, optionally
+                            followed by additional binary data. The string is a description
+                            that the caller may use to further indicate the reason for the
+                            system reset.
+**/
+VOID
+EFIAPI
+ResetSystem (
+  IN EFI_RESET_TYPE               ResetType,
+  IN EFI_STATUS                   ResetStatus,
+  IN UINTN                        DataSize,
+  IN VOID                         *ResetData OPTIONAL
+  )
+{
+  switch (ResetType) {
+  case EfiResetWarm:
+    ResetWarm ();
+    break;
+
+  case EfiResetCold:
+    ResetCold ();
+    break;
+
+  case EfiResetShutdown:
+    ResetShutdown ();
+    return;
+
+  case EfiResetPlatformSpecific:
+    ResetPlatformSpecific (DataSize, ResetData);
+    return;
+
+  default:
+    return;
+  }
+}
diff --git a/ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.inf b/ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.inf
new file mode 100644
index 000000000000..3a65706e8dc6
--- /dev/null
+++ b/ArmVirtPkg/Library/ArmVirtPsciResetSystemPeiLib/ArmVirtPsciResetSystemPeiLib.inf
@@ -0,0 +1,39 @@
+#/** @file
+# Reset System lib using PSCI hypervisor or secure monitor calls
+#
+# Copyright (c) 2008, Apple Inc. All rights reserved.<BR>
+# Copyright (c) 2014-2020, Linaro Ltd. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+#
+#**/
+
+[Defines]
+  INF_VERSION                    = 1.27
+  BASE_NAME                      = ArmVirtPsciResetSystemPeiLib
+  FILE_GUID                      = 551cfb98-c185-41a3-86bf-8cdb7e2a530c
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = ResetSystemLib|PEIM
+
+[Sources]
+  ArmVirtPsciResetSystemPeiLib.c
+
+[Packages]
+  ArmPkg/ArmPkg.dec
+  ArmVirtPkg/ArmVirtPkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+  MdePkg/MdePkg.dec
+
+[LibraryClasses]
+  ArmSmcLib
+  ArmHvcLib
+  BaseLib
+  DebugLib
+  FdtLib
+  HobLib
+
+[Pcd]
+  gArmVirtTokenSpaceGuid.PcdDeviceTreeInitialBaseAddress
-- 
2.20.1