[edk2-platforms][PATCH V1 12/15] Platform/Loongson: Add RealTime Clock lib.

["xianglai" <lixianglai@loongson.cn>]

This library provides interfaces such as
real-time clock initialization
to get time and setting time.

Signed-off-by: xianglai li <lixianglai@loongson.cn>
---
 .../LsRealTimeClockLib/LsRealTimeClock.h      |  41 +++
 .../LsRealTimeClockLib/LsRealTimeClockLib.c   | 343 ++++++++++++++++++
 .../LsRealTimeClockLib/LsRealTimeClockLib.inf |  41 +++
 3 files changed, 425 insertions(+)
 create mode 100644 Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClock.h
 create mode 100644 Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
 create mode 100644 Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf

diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClock.h b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClock.h
new file mode 100644
index 0000000000..74a5c629ab
--- /dev/null
+++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClock.h
@@ -0,0 +1,41 @@
+/** @file
+  Implement EFI RealTimeClock runtime services via RTC Lib.
+
+  Copyright (c) 2021, Loongson Limited. All rights reserved.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+
+#ifndef LS_REAL_TIME_CLOCK_H_
+#define LS_REAL_TIME_CLOCK_H_
+
+#define TOY_WRITE0_REG        0x24
+#define TOY_WRITE1_REG        0x28
+#define TOY_READ0_REG         0x2c
+#define TOY_READ1_REG         0x30
+#define RTC_CTRL_REG          0x40
+
+/* TOY Enable bits */
+#define RTC_ENABLE_BIT          (1UL << 13)
+#define TOY_ENABLE_BIT          (1UL << 11)
+#define OSC_ENABLE_BIT          (1UL << 8)
+
+/*
+ * shift bits and filed mask
+ */
+#define TOY_MON_MASK   0x3f
+#define TOY_DAY_MASK   0x1f
+#define TOY_HOUR_MASK  0x1f
+#define TOY_MIN_MASK   0x3f
+#define TOY_SEC_MASK   0x3f
+#define TOY_MSEC_MASK  0xf
+
+#define TOY_MON_SHIFT  26
+#define TOY_DAY_SHIFT  21
+#define TOY_HOUR_SHIFT 16
+#define TOY_MIN_SHIFT  10
+#define TOY_SEC_SHIFT  4
+
+#endif //__LS_REAL_TIME_CLOCK_H__
diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
new file mode 100644
index 0000000000..cc5e426f03
--- /dev/null
+++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.c
@@ -0,0 +1,343 @@
+/** @file
+  Implement EFI RealTimeClock runtime services via RTC Lib.
+
+  Copyright (c) 2021, Loongson Limited. All rights reserved.
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Uefi.h>
+#include <PiDxe.h>
+
+#include <Guid/EventGroup.h>
+#include <Guid/GlobalVariable.h>
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/IoLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/PcdLib.h>
+#include <Library/RealTimeClockLib.h>
+#include <Library/TimeBaseLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Library/UefiRuntimeLib.h>
+#include <Protocol/RealTimeClock.h>
+#include "LsRealTimeClock.h"
+
+STATIC BOOLEAN                mInitialized = FALSE;
+STATIC EFI_EVENT              mRtcVirtualAddrChangeEvent;
+STATIC UINTN                  mRtcBase = 0X100d0100;
+/*
+  Enable Real-time clock.
+
+  @param VOID
+
+  @retval  VOID
+ */
+VOID
+InitRtc (
+  VOID
+  )
+{
+ UINTN  Val;
+
+  if (!mInitialized) {
+    /* enable rtc */
+    Val  = MmioRead32 (mRtcBase + RTC_CTRL_REG);
+    Val |= TOY_ENABLE_BIT | OSC_ENABLE_BIT;
+    MmioWrite32 (mRtcBase + RTC_CTRL_REG, Val);
+    mInitialized = TRUE;
+  }
+}
+
+/**
+  Returns the current time and date information, and the time-keeping capabilities
+  of the hardware platform.
+
+  @param  Time                   A pointer to storage to receive a snapshot of the current time.
+  @param  Capabilities           An optional pointer to a buffer to receive the real time clock
+                                 device's capabilities.
+
+  @retval EFI_SUCCESS            The operation completed successfully.
+  @retval EFI_INVALID_PARAMETER  Time is NULL.
+  @retval EFI_DEVICE_ERROR       The time could not be retrieved due to hardware error.
+  @retval EFI_SECURITY_VIOLATION The time could not be retrieved due to an authentication failure.
+
+**/
+EFI_STATUS
+EFIAPI
+LibGetTime (
+  OUT EFI_TIME                *Time,
+  OUT EFI_TIME_CAPABILITIES   *Capabilities
+  )
+{
+  UINT32      Val;
+
+  // Ensure Time is a valid pointer
+  if (Time == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  InitRtc ();
+  Val = MmioRead32 (mRtcBase + TOY_READ1_REG);
+  Time->Year = Val + 1900;
+
+  Val = MmioRead32 (mRtcBase + TOY_READ0_REG);
+  Time->Month =  ((Val >> TOY_MON_SHIFT) & TOY_MON_MASK) - 1;
+  Time->Day   =  (Val >> TOY_DAY_SHIFT) & TOY_DAY_MASK;
+  Time->Hour  =  (Val >> TOY_HOUR_SHIFT) & TOY_HOUR_MASK;
+  Time->Minute = (Val >> TOY_MIN_SHIFT) & TOY_MIN_MASK;
+  Time->Second = (Val >> TOY_SEC_SHIFT) & TOY_SEC_MASK;
+  Time->Nanosecond  = 0;
+  return EFI_SUCCESS;
+}
+
+
+/**
+  Sets the current local time and date information.
+
+  @param  Time                  A pointer to the current time.
+
+  @retval EFI_SUCCESS           The operation completed successfully.
+  @retval EFI_INVALID_PARAMETER A time field is out of range.
+  @retval EFI_DEVICE_ERROR      The time could not be set due due to hardware error.
+
+**/
+EFI_STATUS
+EFIAPI
+LibSetTime (
+  IN  EFI_TIME                *Time
+  )
+{
+  UINT32      Val;
+
+  // Initialize the hardware if not already done
+  InitRtc ();
+
+  Val = 0;
+  Val |= (Time->Second << TOY_SEC_SHIFT);
+  Val |= (Time->Minute << TOY_MIN_SHIFT);
+  Val |= (Time->Hour   << TOY_HOUR_SHIFT);
+  Val |= (Time->Day    << TOY_DAY_SHIFT);
+  Val |= ((Time->Month + 1) << TOY_MON_SHIFT);
+  MmioWrite32 (mRtcBase + TOY_WRITE0_REG, Val);
+
+  Val = Time->Year - 1900;
+  MmioWrite32 (mRtcBase + TOY_WRITE1_REG, Val);
+  return EFI_SUCCESS;
+}
+
+
+/**
+  Returns the current wakeup alarm clock setting.
+
+  @param  Enabled               Indicates if the alarm is currently enabled or disabled.
+  @param  Pending               Indicates if the alarm signal is pending and requires acknowledgement.
+  @param  Time                  The current alarm setting.
+
+  @retval EFI_SUCCESS           The alarm settings were returned.
+  @retval EFI_INVALID_PARAMETER Any parameter is NULL.
+  @retval EFI_DEVICE_ERROR      The wakeup time could not be retrieved due to a hardware error.
+
+**/
+EFI_STATUS
+EFIAPI
+LibGetWakeupTime (
+  OUT BOOLEAN     *Enabled,
+  OUT BOOLEAN     *Pending,
+  OUT EFI_TIME    *Time
+  )
+{
+  // Not a required feature
+  return EFI_UNSUPPORTED;
+}
+
+
+/**
+  Sets the system wakeup alarm clock time.
+
+  @param  Enabled               Enable or disable the wakeup alarm.
+  @param  Time                  If Enable is TRUE, the time to set the wakeup alarm for.
+
+  @retval EFI_SUCCESS           If Enable is TRUE, then the wakeup alarm was enabled. If
+                                Enable is FALSE, then the wakeup alarm was disabled.
+  @retval EFI_INVALID_PARAMETER A time field is out of range.
+  @retval EFI_DEVICE_ERROR      The wakeup time could not be set due to a hardware error.
+  @retval EFI_UNSUPPORTED       A wakeup timer is not supported on this platform.
+
+**/
+EFI_STATUS
+EFIAPI
+LibSetWakeupTime (
+  IN BOOLEAN      Enabled,
+  OUT EFI_TIME    *Time
+  )
+{
+  // Not a required feature
+  return EFI_UNSUPPORTED;
+}
+
+/**
+  Fixup internal data so that EFI can be call in virtual mode.
+  Call the passed in Child Notify event and convert any pointers in
+  lib to virtual mode.
+
+  @param[in]    Event   The Event that is being processed
+  @param[in]    Context Event Context
+**/
+VOID
+EFIAPI
+LibRtcVirtualNotifyEvent (
+  IN EFI_EVENT        Event,
+  IN VOID             *Context
+  )
+{
+  //
+  // Only needed if you are going to support the OS calling RTC functions in virtual mode.
+  // You will need to call EfiConvertPointer (). To convert any stored physical addresses
+  // to virtual address. After the OS transitions to calling in virtual mode, all future
+  // runtime calls will be made in virtual mode.
+  //
+  EfiConvertPointer (0x0, (VOID**)&mRtcBase);
+  return;
+}
+
+/** Add the RTC controller address range to the memory map.
+
+  @param [in]  ImageHandle  The handle to the image.
+  @param [in]  RtcPageBase  Base address of the RTC controller.
+
+  @retval EFI_SUCCESS             Success.
+  @retval EFI_INVALID_PARAMETER   A parameter is invalid.
+  @retval EFI_NOT_FOUND           Flash device not found.
+**/
+EFI_STATUS
+KvmtoolRtcMapMemory (
+  IN EFI_HANDLE               ImageHandle,
+  IN EFI_PHYSICAL_ADDRESS     RtcPageBase
+  )
+{
+  EFI_STATUS  Status;
+
+  Status = gDS->AddMemorySpace (
+                  EfiGcdMemoryTypeMemoryMappedIo,
+                  RtcPageBase,
+                  EFI_PAGE_SIZE,
+                  EFI_MEMORY_UC | EFI_MEMORY_RUNTIME
+                  );
+  if (EFI_ERROR (Status)) {
+    DEBUG ((
+      DEBUG_ERROR, "Failed to add memory space. Status = %r\n",
+      Status
+      ));
+    return Status;
+  }
+
+  Status = gDS->AllocateMemorySpace (
+                  EfiGcdAllocateAddress,
+                  EfiGcdMemoryTypeMemoryMappedIo,
+                  0,
+                  EFI_PAGE_SIZE,
+                  &RtcPageBase,
+                  ImageHandle,
+                  NULL
+                  );
+  if (EFI_ERROR (Status)) {
+    DEBUG ((
+      DEBUG_ERROR,
+      "Failed to allocate memory space. Status = %r\n",
+      Status
+      ));
+    gDS->RemoveMemorySpace (
+           RtcPageBase,
+           EFI_PAGE_SIZE
+           );
+    return Status;
+  }
+
+  Status = gDS->SetMemorySpaceAttributes (
+                  RtcPageBase,
+                  EFI_PAGE_SIZE,
+                  EFI_MEMORY_UC | EFI_MEMORY_RUNTIME
+                  );
+  if (EFI_ERROR (Status)) {
+    DEBUG ((
+      DEBUG_ERROR,
+      "Failed to set memory attributes. Status = %r\n",
+      Status
+      ));
+
+    gDS->FreeMemorySpace (
+           RtcPageBase,
+           EFI_PAGE_SIZE
+           );
+
+    gDS->RemoveMemorySpace (
+           RtcPageBase,
+           EFI_PAGE_SIZE
+           );
+  }
+
+  return Status;
+}
+
+/**
+  This is the declaration of an EFI image entry point. This can be the entry point to an application
+  written to this specification, an EFI boot service driver, or an EFI runtime driver.
+
+  @param  ImageHandle           Handle that identifies the loaded image.
+  @param  SystemTable           System Table for this image.
+
+  @retval EFI_SUCCESS           The operation completed successfully.
+
+**/
+EFI_STATUS
+EFIAPI
+LibRtcInitialize (
+  IN EFI_HANDLE                            ImageHandle,
+  IN EFI_SYSTEM_TABLE                      *SystemTable
+  )
+{
+  EFI_STATUS    Status;
+  EFI_HANDLE    Handle;
+
+  Status = KvmtoolRtcMapMemory (ImageHandle, (mRtcBase & ~EFI_PAGE_MASK));
+  if (EFI_ERROR (Status)) {
+    DEBUG ((
+      DEBUG_ERROR,
+      "Failed to map memory for loongson 7A RTC. Status = %r\n",
+      Status
+      ));
+    return Status;
+  }
+
+  // Setup the setters and getters
+  gRT->GetTime       = LibGetTime;
+  gRT->SetTime       = LibSetTime;
+
+  // Install the protocol
+  Handle = NULL;
+  Status = gBS->InstallMultipleProtocolInterfaces (
+                  &Handle,
+                  &gEfiRealTimeClockArchProtocolGuid,  NULL,
+                  NULL
+                 );
+  ASSERT_EFI_ERROR (Status);
+
+  //
+  // Register for the virtual address change event
+  //
+  Status = gBS->CreateEventEx (
+                  EVT_NOTIFY_SIGNAL,
+                  TPL_NOTIFY,
+                  LibRtcVirtualNotifyEvent,
+                  NULL,
+                  &gEfiEventVirtualAddressChangeGuid,
+                  &mRtcVirtualAddrChangeEvent
+                  );
+  ASSERT_EFI_ERROR (Status);
+  return Status;
+}
diff --git a/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
new file mode 100644
index 0000000000..c985f7a727
--- /dev/null
+++ b/Platform/Loongson/LoongArchQemuPkg/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf
@@ -0,0 +1,41 @@
+## @file
+#
+#  Copyright (c) 2021, Loongson Limited. All rights reserved.
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = LsRealTimeClockLib
+  FILE_GUID                      = 9793a3da-1869-4fdf-88b1-c6484341f50b
+  MODULE_TYPE                    = BASE
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = RealTimeClockLib
+
+[Sources.common]
+  LsRealTimeClockLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
+  Platform/Loongson/LoongArchQemuPkg/Loongson.dec
+
+[LibraryClasses]
+  IoLib
+  UefiLib
+  DebugLib
+  PcdLib
+  DxeServicesTableLib
+  UefiRuntimeLib
+
+[Guids]
+  gEfiEventVirtualAddressChangeGuid
+
+[Protocols]
+  gEfiRealTimeClockArchProtocolGuid             # PROTOCOL ALWAYS_PRODUCED
+
+[Depex]
+  TRUE
+
-- 
2.27.0