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authorArd Biesheuvel <ard.biesheuvel@linaro.org>2016-04-08 11:45:03 +0200
committerArd Biesheuvel <ard.biesheuvel@linaro.org>2016-04-13 16:55:24 +0200
commit658e7a41de3b85ed069f8395d7bb807249a57399 (patch)
treeb2122a0eece186a54f0ea3cfc2fbc3104464659f /ArmVirtPkg/Library/ArmVirtPL031FdtClientLib
parent8457f5e40277d682b2de25f7769106a2cf803216 (diff)
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ArmVirtPkg: implement ArmVirtPL031FdtClientLib
This implements a library ArmVirtPL031FdtClientLib which is intended to be incorporated into RealTimeClockRuntimeDxe via NULL library class resolution. This allows us to make RealTimeClockRuntimeDxe depend on the FDT client protocol, and discover the PL031 base address from the device tree directly rather than relying on VirtFdtDxe to set the dynamic PCDs. The NULL library class resolution approach to strictly order production and consumption of dynamic PCDs is not generally safe in cases such as this one, where the producer and the consumer of the PCD are both libraries. However, since the PCD is produced in this library's constructor, and the consumer library's constructor 'LibRtcInitialize' is not a 'true' constructor (it is invoked explicitly by RealTimeClockRuntimeDxe), this case is guaranteed to be safe after all. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Diffstat (limited to 'ArmVirtPkg/Library/ArmVirtPL031FdtClientLib')
-rw-r--r--ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.c82
-rw-r--r--ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.inf49
2 files changed, 131 insertions, 0 deletions
diff --git a/ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.c b/ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.c
new file mode 100644
index 0000000..3c4e44c
--- /dev/null
+++ b/ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.c
@@ -0,0 +1,82 @@
+/** @file
+ FDT client library for ARM's PL031 RTC driver
+
+ Copyright (c) 2016, Linaro Ltd. 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
+ 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 <Uefi.h>
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/PcdLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+#include <Protocol/FdtClient.h>
+
+RETURN_STATUS
+EFIAPI
+ArmVirtPL031FdtClientLibConstructor (
+ VOID
+ )
+{
+ EFI_STATUS Status;
+ FDT_CLIENT_PROTOCOL *FdtClient;
+ INT32 Node;
+ CONST UINT64 *Reg;
+ UINT32 RegSize;
+ UINT64 RegBase;
+
+ Status = gBS->LocateProtocol (&gFdtClientProtocolGuid, NULL,
+ (VOID **)&FdtClient);
+ ASSERT_EFI_ERROR (Status);
+
+ Status = FdtClient->FindCompatibleNode (FdtClient, "arm,pl031", &Node);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((EFI_D_WARN, "%a: No 'arm,pl031' compatible DT node found\n",
+ __FUNCTION__));
+ return EFI_SUCCESS;
+ }
+
+ Status = FdtClient->GetNodeProperty (FdtClient, Node, "reg",
+ (CONST VOID **)&Reg, &RegSize);
+ if (EFI_ERROR (Status)) {
+ DEBUG ((EFI_D_WARN,
+ "%a: No 'reg' property found in 'arm,pl031' compatible DT node\n",
+ __FUNCTION__));
+ return EFI_SUCCESS;
+ }
+
+ ASSERT (RegSize == 16);
+
+ RegBase = SwapBytes64 (Reg[0]);
+ ASSERT (RegBase < MAX_UINT32);
+
+ PcdSet32 (PcdPL031RtcBase, (UINT32)RegBase);
+
+ DEBUG ((EFI_D_INFO, "Found PL031 RTC @ 0x%Lx\n", RegBase));
+
+ if (!FeaturePcdGet (PcdPureAcpiBoot)) {
+ //
+ // UEFI takes ownership of the RTC hardware, and exposes its functionality
+ // through the UEFI Runtime Services GetTime, SetTime, etc. This means we
+ // need to disable it in the device tree to prevent the OS from attaching
+ // its device driver as well.
+ //
+ Status = FdtClient->SetNodeProperty (FdtClient, Node, "status",
+ "disabled", sizeof ("disabled"));
+ if (EFI_ERROR (Status)) {
+ DEBUG ((EFI_D_WARN, "Failed to set PL031 status to 'disabled'\n"));
+ }
+ }
+
+ return EFI_SUCCESS;
+}
diff --git a/ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.inf b/ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.inf
new file mode 100644
index 0000000..32dbff6
--- /dev/null
+++ b/ArmVirtPkg/Library/ArmVirtPL031FdtClientLib/ArmVirtPL031FdtClientLib.inf
@@ -0,0 +1,49 @@
+#/** @file
+# FDT client library for ARM's PL031 RTC driver
+#
+# Copyright (c) 2016, Linaro Ltd. All rights reserved.
+#
+# 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.
+#
+#**/
+
+[Defines]
+ INF_VERSION = 0x00010005
+ BASE_NAME = ArmVirtPL031FdtClientLib
+ FILE_GUID = 13173319-B270-4669-8592-3BB2B31E9E29
+ MODULE_TYPE = BASE
+ VERSION_STRING = 1.0
+ LIBRARY_CLASS = ArmVirtPL031FdtClientLib|DXE_DRIVER DXE_RUNTIME_DRIVER
+ CONSTRUCTOR = ArmVirtPL031FdtClientLibConstructor
+
+[Sources]
+ ArmVirtPL031FdtClientLib.c
+
+[Packages]
+ ArmPlatformPkg/ArmPlatformPkg.dec
+ ArmVirtPkg/ArmVirtPkg.dec
+ MdePkg/MdePkg.dec
+
+[LibraryClasses]
+ BaseLib
+ DebugLib
+ PcdLib
+ UefiBootServicesTableLib
+
+[Protocols]
+ gFdtClientProtocolGuid ## CONSUMES
+
+[Pcd]
+ gArmPlatformTokenSpaceGuid.PcdPL031RtcBase
+
+[FeaturePcd]
+ gArmVirtTokenSpaceGuid.PcdPureAcpiBoot
+
+[Depex]
+ gFdtClientProtocolGuid