OvmfPkg/LoongArchVirt: Add real time clock library

This library is provides real time clock for LoongArch virtual machine.

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4584

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Bibo Mao <maobibo@loongson.cn>
Cc: Dongyan Qian <qiandongyan@loongson.cn>
Signed-off-by: Chao Li <lichao@loongson.cn>
Co-authored-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
Co-authored-by: Xianglai Li <lixianglai@loongson.cn>

OvmfPkg/LoongArchVirt/Library/LsRealTimeClockLib/LsRealTimeClock.h

@@ -0,0 +1,40 @@
+/** @file
+  Implement EFI RealTimeClock runtime services via RTC Lib.
+
+  Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR>
+
+  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_

OvmfPkg/LoongArchVirt/Library/LsRealTimeClockLib/LsRealTimeClockLib.c

@@ -0,0 +1,325 @@
+/** @file
+  Implement EFI RealTimeClock runtime services via RTC Lib.
+
+  Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/DebugLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/HobLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiRuntimeLib.h>
+
+#include "LsRealTimeClock.h"
+
+STATIC BOOLEAN    mInitialized = FALSE;
+STATIC EFI_EVENT  mRtcVirtualAddrChangeEvent;
+STATIC UINTN      mRtcBase;
+
+/*
+  Enable Real-time clock.
+
+  @param VOID
+
+  @retval  VOID
+ */
+STATIC
+VOID
+InitRtc (
+  VOID
+  )
+{
+  UINTN              Val;
+  EFI_HOB_GUID_TYPE  *GuidHob   = NULL;
+  VOID               *DataInHob = NULL;
+
+  if (!mInitialized) {
+    /* Enable rtc */
+    GuidHob = GetFirstGuidHob (&gRtcRegisterBaseAddressHobGuid);
+    if (GuidHob) {
+      DataInHob = GET_GUID_HOB_DATA (GuidHob);
+      mRtcBase  = (UINT64)(*(UINTN *)DataInHob);
+      Val       = MmioRead32 (mRtcBase + RTC_CTRL_REG);
+      Val      |= TOY_ENABLE_BIT | OSC_ENABLE_BIT;
+      MmioWrite32 (mRtcBase + RTC_CTRL_REG, Val);
+      mInitialized = TRUE;
+    } else {
+      DebugPrint (EFI_D_INFO, "RTC register address not found!\n");
+      ASSERT (FALSE);
+    }
+  }
+}
+
+/**
+  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;
+  }
+
+  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;
+  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
+
+  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  << 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
+**/
+STATIC
+VOID
+EFIAPI
+VirtualNotifyEvent (
+  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.
+**/
+STATIC
+EFI_STATUS
+MapRtcResources (
+  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;
+
+  InitRtc ();
+  Status = MapRtcResources (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;
+  }
+
+  //
+  // Register for the virtual address change event
+  //
+  Status = gBS->CreateEventEx (
+                  EVT_NOTIFY_SIGNAL,
+                  TPL_NOTIFY,
+                  VirtualNotifyEvent,
+                  NULL,
+                  &gEfiEventVirtualAddressChangeGuid,
+                  &mRtcVirtualAddrChangeEvent
+                  );
+  ASSERT_EFI_ERROR (Status);
+  return Status;
+}

OvmfPkg/LoongArchVirt/Library/LsRealTimeClockLib/LsRealTimeClockLib.inf

@@ -0,0 +1,44 @@
+## @file
+#  LoongArch64 CPU Real Time Clock DXE Phase Library.
+#
+# Copyright (c) 2024 Loongson Technology Corporation Limited. All rights reserved.<BR>
+#
+#  SPDX-License-Identifier: BSD-2-Clause-Patent
+#
+##
+
+[Defines]
+  INF_VERSION                    = 1.29
+  BASE_NAME                      = LsRealTimeClockLib
+  FILE_GUID                      = 9793a3da-1869-4fdf-88b1-c6484341f50b
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = RealTimeClockLib
+
+#
+#  VALID_ARCHITECTURES           = LOONGARCH64
+#
+
+[Sources]
+  LsRealTimeClockLib.c
+
+[Packages]
+  EmbeddedPkg/EmbeddedPkg.dec
+  MdePkg/MdePkg.dec
+  OvmfPkg/OvmfPkg.dec
+
+[LibraryClasses]
+  DebugLib
+  DxeServicesTableLib
+  HobLib
+  IoLib
+  PcdLib
+  UefiBootServicesTableLib
+  UefiRuntimeLib
+
+[Guids]
+  gEfiEventVirtualAddressChangeGuid
+  gRtcRegisterBaseAddressHobGuid
+
+[Depex]
+  TRUE