[RFC PATCH edk2-platforms 1/3] Silicon/NXP: add RTC support library for PCF8563 I2C IP

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

Add a RealTimeClockLib implementation for the NXP PCF8563 as used on
the Socionext Developer Box board. Note that the standard I2C protocol
stack does not support runtime use, so this driver invokes the I2C master
protocol directly. This requires support from the platform side as well,
and so this driver will only attach to a I2C master that has the
gPcf8563RealTimeClockLibI2cMasterProtolGuid protocol installed on its
handle. It is up to the platform to ensure that the driver producing
the I2C master protocol in question is runtime capable, and is not
shared with the I2C protocol stack (i.e., it should not have the I2C
Bus Configuration Management protocol installed as well).

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c   | 385 ++++++++++++++++++++
 Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.dec |  29 ++
 Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf |  52 +++
 3 files changed, 466 insertions(+)

diff --git a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c
new file mode 100644
index 000000000000..fea65a225d7f
--- /dev/null
+++ b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.c
@@ -0,0 +1,385 @@
+/** @file
+
+  Copyright (c) 2017, 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 <PiDxe.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/RealTimeClockLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+#include <Library/UefiRuntimeLib.h>
+#include <Protocol/I2cMaster.h>
+
+#define SLAVE_ADDRESS             (FixedPcdGet8 (PcdI2cSlaveAddress))
+#define PCF8563_DATA_REG_OFFSET   0x2
+
+#define PCF8563_SECONDS_MASK      0x7f
+#define PCF8563_MINUTES_MASK      0x7f
+#define PCF8563_HOURS_MASK        0x3f
+#define PCF8563_DAYS_MASK         0x3f
+#define PCF8563_WEEKDAYS_MASK     0x07
+#define PCF8563_MONTHS_MASK       0x1f
+#define PCF8563_CENTURY_MASK      0x80
+
+#define EPOCH_BASE                2000
+
+STATIC EFI_HANDLE                 mI2cMasterHandle;
+STATIC VOID                       *mDriverEventRegistration;
+STATIC EFI_I2C_MASTER_PROTOCOL    *mI2cMaster;
+STATIC EFI_EVENT                  mRtcVirtualAddrChangeEvent;
+
+typedef struct {
+  UINTN                           OperationCount;
+  EFI_I2C_OPERATION               SetAddressOp;
+  EFI_I2C_OPERATION               GetSetDateTimeOp;
+} RTC_I2C_REQUEST;
+
+#pragma pack(1)
+typedef struct {
+  UINT8     VL_seconds;
+  UINT8     Minutes;
+  UINT8     Hours;
+  UINT8     Days;
+  UINT8     Weekdays;
+  UINT8     Century_months;
+  UINT8     Years;
+} RTC_DATETIME;
+#pragma pack()
+
+/**
+  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.
+
+**/
+EFI_STATUS
+EFIAPI
+LibGetTime (
+  OUT EFI_TIME                *Time,
+  OUT EFI_TIME_CAPABILITIES   *Capabilities
+  )
+{
+  RTC_I2C_REQUEST             Op;
+  RTC_DATETIME                DateTime;
+  EFI_STATUS                  Status;
+  UINT8                       Reg;
+
+  if (Time == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  if (mI2cMaster == NULL) {
+    return EFI_DEVICE_ERROR;
+  }
+
+  Reg = PCF8563_DATA_REG_OFFSET;
+
+  Op.OperationCount = 2;
+
+  Op.SetAddressOp.Flags = 0;
+  Op.SetAddressOp.LengthInBytes = 1;
+  Op.SetAddressOp.Buffer = &Reg;
+
+  Op.GetSetDateTimeOp.Flags = I2C_FLAG_READ;
+  Op.GetSetDateTimeOp.LengthInBytes = sizeof (RTC_DATETIME);
+  Op.GetSetDateTimeOp.Buffer = (VOID *)&DateTime;
+
+  Status = mI2cMaster->StartRequest (mI2cMaster, SLAVE_ADDRESS,
+                         (VOID *)&Op, NULL, NULL);
+  if (EFI_ERROR (Status)) {
+    return EFI_DEVICE_ERROR;
+  }
+
+  Time->Second  = BcdToDecimal8 (DateTime.VL_seconds & PCF8563_SECONDS_MASK);
+  Time->Minute  = BcdToDecimal8 (DateTime.Minutes & PCF8563_MINUTES_MASK);
+  Time->Hour    = BcdToDecimal8 (DateTime.Hours & PCF8563_HOURS_MASK);
+  Time->Day     = BcdToDecimal8 (DateTime.Days & PCF8563_DAYS_MASK);
+  Time->Month   = BcdToDecimal8 (DateTime.Century_months & PCF8563_MONTHS_MASK);
+  Time->Year    = BcdToDecimal8 (DateTime.Years) + EPOCH_BASE;
+
+  if (DateTime.Century_months & PCF8563_CENTURY_MASK) {
+    Time->Year += 100;
+  }
+
+  Time->Daylight  = EFI_TIME_ADJUST_DAYLIGHT;
+  Time->TimeZone  = 0; /* UTC */
+
+  if (Capabilities != NULL) {
+    Capabilities->Resolution = 1;
+    Capabilities->Accuracy = 0;
+    Capabilities->SetsToZero = TRUE;
+  }
+  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
+  )
+{
+  RTC_I2C_REQUEST             Op;
+  RTC_DATETIME                DateTime;
+  EFI_STATUS                  Status;
+  UINT8                       Reg;
+
+  if (mI2cMaster == NULL) {
+    return EFI_DEVICE_ERROR;
+  }
+
+  DateTime.VL_seconds     = DecimalToBcd8 (Time->Second);
+  DateTime.Minutes        = DecimalToBcd8 (Time->Minute);
+  DateTime.Hours          = DecimalToBcd8 (Time->Hour);
+  DateTime.Days           = DecimalToBcd8 (Time->Day);
+  DateTime.Century_months = DecimalToBcd8 (Time->Month);
+  DateTime.Years          = DecimalToBcd8 (Time->Year % 100);
+  if (Time->Year >= EPOCH_BASE + 100) {
+    DateTime.Century_months |= PCF8563_CENTURY_MASK;
+  }
+
+  Reg = PCF8563_DATA_REG_OFFSET;
+
+  Op.OperationCount = 2;
+
+  Op.SetAddressOp.Flags = 0;
+  Op.SetAddressOp.LengthInBytes = 1;
+  Op.SetAddressOp.Buffer = &Reg;
+
+  Op.GetSetDateTimeOp.Flags = 0;
+  Op.GetSetDateTimeOp.LengthInBytes = sizeof (RTC_DATETIME);
+  Op.GetSetDateTimeOp.Buffer = (VOID *)&DateTime;
+
+  Status = mI2cMaster->StartRequest (mI2cMaster, SLAVE_ADDRESS,
+                         (VOID *)&Op, NULL, NULL);
+  if (EFI_ERROR (Status)) {
+    return EFI_DEVICE_ERROR;
+  }
+  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
+  )
+{
+  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
+  )
+{
+  return EFI_UNSUPPORTED;
+}
+
+STATIC
+VOID
+DriverRegistrationEvent (
+  IN  EFI_EVENT       Event,
+  IN  VOID            *Context
+  )
+{
+  EFI_HANDLE                Handle[2];
+  UINTN                     BufferSize;
+  EFI_STATUS                Status;
+  EFI_I2C_MASTER_PROTOCOL   *I2cMaster;
+  UINTN                     BusFrequency;
+
+  //
+  // Try to connect the newly registered driver to our handle.
+  //
+  do {
+    BufferSize = sizeof (EFI_HANDLE);
+    Status = gBS->LocateHandle (ByRegisterNotify,
+                                &gEfiDriverBindingProtocolGuid,
+                                mDriverEventRegistration,
+                                &BufferSize,
+                                Handle);
+    if (EFI_ERROR (Status)) {
+      if (Status != EFI_NOT_FOUND) {
+        DEBUG ((DEBUG_WARN, "%a: gBS->LocateHandle () returned %r\n",
+          __FUNCTION__, Status));
+      }
+      break;
+    }
+
+    //
+    // Check if we can connect our handle to this driver.
+    //
+    Handle[1] = NULL;
+    Status = gBS->ConnectController (mI2cMasterHandle, Handle, NULL, FALSE);
+    if (EFI_ERROR (Status)) {
+      continue;
+    }
+
+    DEBUG ((DEBUG_INFO, "%a: found I2C master!\n", __FUNCTION__));
+
+    gBS->CloseEvent (Event);
+
+    Status = gBS->OpenProtocol (mI2cMasterHandle, &gEfiI2cMasterProtocolGuid,
+                    (VOID **)&I2cMaster, gImageHandle, NULL,
+                    EFI_OPEN_PROTOCOL_EXCLUSIVE);
+    ASSERT_EFI_ERROR (Status);
+
+    Status = I2cMaster->Reset (I2cMaster);
+    if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_ERROR, "%a: I2CMaster->Reset () failed - %r\n",
+        __FUNCTION__, Status));
+      break;
+    }
+
+    BusFrequency = FixedPcdGet16 (PcdI2cBusFrequency);
+    Status = I2cMaster->SetBusFrequency (I2cMaster, &BusFrequency);
+    if (EFI_ERROR (Status)) {
+      DEBUG ((DEBUG_ERROR, "%a: I2CMaster->SetBusFrequency () failed - %r\n",
+        __FUNCTION__, Status));
+      break;
+    }
+
+    mI2cMaster = I2cMaster;
+    break;
+  } while (TRUE);
+}
+
+/**
+  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
+  )
+{
+  EfiConvertPointer (0x0, (VOID **)&mI2cMaster);
+}
+
+/**
+  Library entry point
+
+  @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;
+  UINTN               BufferSize;
+
+  //
+  // Find the handle that marks the controller
+  // that will provide the I2C master protocol.
+  //
+  BufferSize = sizeof (EFI_HANDLE);
+  Status = gBS->LocateHandle (ByProtocol,
+                  &gPcf8563RealTimeClockLibI2cMasterProtolGuid, NULL,
+                  &BufferSize, &mI2cMasterHandle);
+  ASSERT_EFI_ERROR (Status);
+
+  //
+  // Register a protocol registration notification callback on the driver
+  // binding protocol so we can attempt to connect our I2C master to it
+  // as soon as it appears.
+  //
+  EfiCreateProtocolNotifyEvent (
+    &gEfiDriverBindingProtocolGuid,
+    TPL_CALLBACK,
+    DriverRegistrationEvent,
+    NULL,
+    &mDriverEventRegistration);
+
+  //
+  // Register for the virtual address change event
+  //
+  Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL, TPL_NOTIFY,
+                  LibRtcVirtualNotifyEvent, NULL,
+                  &gEfiEventVirtualAddressChangeGuid,
+                  &mRtcVirtualAddrChangeEvent);
+  ASSERT_EFI_ERROR (Status);
+
+  return EFI_SUCCESS;
+}
diff --git a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.dec b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.dec
new file mode 100644
index 000000000000..bc8fc60c0602
--- /dev/null
+++ b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.dec
@@ -0,0 +1,29 @@
+#/** @file
+#
+#  Copyright (c) 2017, 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.
+#
+#
+#**/
+
+[Defines]
+  DEC_SPECIFICATION              = 0x0001001A
+  PACKAGE_NAME                   = Pcf8563RealTimeClockLib
+  PACKAGE_GUID                   = 44d63668-c86b-446a-b303-f3a5176702aa
+  PACKAGE_VERSION                = 0.1
+
+[Guids]
+  gPcf8563RealTimeClockLibTokenSpaceGuid = { 0xaaf5b169, 0x93a0, 0x4d60, { 0xba, 0xe4, 0x06, 0x07, 0x92, 0x8e, 0x63, 0xdd }}
+
+[Protocols]
+  gPcf8563RealTimeClockLibI2cMasterProtolGuid = { 0xa6af18ae, 0x3bd5, 0x4af9, { 0xbb, 0x6a, 0xdb, 0x85, 0x07, 0x62, 0x81, 0x38 }}
+
+[PcdsFixedAtBuild]
+  gPcf8563RealTimeClockLibTokenSpaceGuid.PcdI2cSlaveAddress|0x51|UINT8|0x00000001
+  gPcf8563RealTimeClockLibTokenSpaceGuid.PcdI2cBusFrequency|400|UINT16|0x00000002
diff --git a/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf
new file mode 100644
index 000000000000..e1e001162144
--- /dev/null
+++ b/Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.inf
@@ -0,0 +1,52 @@
+#/** @file
+#
+#  Copyright (c) 2017, 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.
+#
+#
+#**/
+
+[Defines]
+  INF_VERSION                    = 0x0001001A
+  BASE_NAME                      = Pcf8563RealTimeClockLib
+  FILE_GUID                      = 1e3d33f3-a671-4116-bd81-6b435296c1e0
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = RealTimeClockLib
+
+[Sources.common]
+  Pcf8563RealTimeClockLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  EmbeddedPkg/EmbeddedPkg.dec
+  Silicon/NXP/Library/Pcf8563RealTimeClockLib/Pcf8563RealTimeClockLib.dec
+
+[LibraryClasses]
+  BaseMemoryLib
+  DebugLib
+  IoLib
+  UefiBootServicesTableLib
+  UefiLib
+  UefiRuntimeLib
+
+[Guids]
+  gEfiEventVirtualAddressChangeGuid
+
+[Protocols]
+  gEfiDriverBindingProtocolGuid                   ## CONSUMES
+  gEfiI2cMasterProtocolGuid                       ## CONSUMES
+  gPcf8563RealTimeClockLibI2cMasterProtolGuid     ## CONSUMES
+
+[FixedPcd]
+  gPcf8563RealTimeClockLibTokenSpaceGuid.PcdI2cSlaveAddress
+  gPcf8563RealTimeClockLibTokenSpaceGuid.PcdI2cBusFrequency
+
+[Depex]
+  gPcf8563RealTimeClockLibI2cMasterProtolGuid
-- 
2.11.0