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diff --git a/ArmPlatformPkg/Library/PL011UartLib/PL011UartLib.c b/ArmPlatformPkg/Library/PL011UartLib/PL011UartLib.c
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+/** @file
+ Serial I/O Port library functions with no library constructor/destructor
+
+ Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
+ Copyright (c) 2011 - 2016, ARM 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/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+
+#include <Protocol/SerialIo.h>
+
+#include "PL011Uart.h"
+
+#define FRACTION_PART_SIZE_IN_BITS 6
+#define FRACTION_PART_MASK ((1 << FRACTION_PART_SIZE_IN_BITS) - 1)
+
+//
+// EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE is the only
+// control bit that is not supported.
+//
+STATIC CONST UINT32 mInvalidControlBits = EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE;
+
+/**
+
+ Initialise the serial port to the specified settings.
+ The serial port is re-configured only if the specified settings
+ are different from the current settings.
+ All unspecified settings will be set to the default values.
+
+ @param UartBase The base address of the serial device.
+ @param UartClkInHz The clock in Hz for the serial device.
+ Ignored if the PCD PL011UartInteger is not 0
+ @param BaudRate The baud rate of the serial device. If the
+ baud rate is not supported, the speed will be
+ reduced to the nearest supported one and the
+ variable's value will be updated accordingly.
+ @param ReceiveFifoDepth The number of characters the device will
+ buffer on input. Value of 0 will use the
+ device's default FIFO depth.
+ @param Parity If applicable, this is the EFI_PARITY_TYPE
+ that is computed or checked as each character
+ is transmitted or received. If the device
+ does not support parity, the value is the
+ default parity value.
+ @param DataBits The number of data bits in each character.
+ @param StopBits If applicable, the EFI_STOP_BITS_TYPE number
+ of stop bits per character.
+ If the device does not support stop bits, the
+ value is the default stop bit value.
+
+ @retval RETURN_SUCCESS All attributes were set correctly on the
+ serial device.
+ @retval RETURN_INVALID_PARAMETER One or more of the attributes has an
+ unsupported value.
+
+**/
+RETURN_STATUS
+EFIAPI
+PL011UartInitializePort (
+ IN UINTN UartBase,
+ IN UINT32 UartClkInHz,
+ IN OUT UINT64 *BaudRate,
+ IN OUT UINT32 *ReceiveFifoDepth,
+ IN OUT EFI_PARITY_TYPE *Parity,
+ IN OUT UINT8 *DataBits,
+ IN OUT EFI_STOP_BITS_TYPE *StopBits
+ )
+{
+ UINT32 LineControl;
+ UINT32 Divisor;
+ UINT32 Integer;
+ UINT32 Fractional;
+ UINT32 HardwareFifoDepth;
+
+ HardwareFifoDepth = (PL011_UARTPID2_VER (MmioRead32 (UartBase + UARTPID2)) \
+ > PL011_VER_R1P4) \
+ ? 32 : 16 ;
+ // The PL011 supports a buffer of 1, 16 or 32 chars. Therefore we can accept
+ // 1 char buffer as the minimum FIFO size. Because everything can be rounded
+ // down, there is no maximum FIFO size.
+ if ((*ReceiveFifoDepth == 0) || (*ReceiveFifoDepth >= HardwareFifoDepth)) {
+ // Enable FIFO
+ LineControl = PL011_UARTLCR_H_FEN;
+ *ReceiveFifoDepth = HardwareFifoDepth;
+ } else {
+ // Disable FIFO
+ LineControl = 0;
+ // Nothing else to do. 1 byte FIFO is default.
+ *ReceiveFifoDepth = 1;
+ }
+
+ //
+ // Parity
+ //
+ switch (*Parity) {
+ case DefaultParity:
+ *Parity = NoParity;
+ case NoParity:
+ // Nothing to do. Parity is disabled by default.
+ break;
+ case EvenParity:
+ LineControl |= (PL011_UARTLCR_H_PEN | PL011_UARTLCR_H_EPS);
+ break;
+ case OddParity:
+ LineControl |= PL011_UARTLCR_H_PEN;
+ break;
+ case MarkParity:
+ LineControl |= ( PL011_UARTLCR_H_PEN \
+ | PL011_UARTLCR_H_SPS \
+ | PL011_UARTLCR_H_EPS);
+ break;
+ case SpaceParity:
+ LineControl |= (PL011_UARTLCR_H_PEN | PL011_UARTLCR_H_SPS);
+ break;
+ default:
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ //
+ // Data Bits
+ //
+ switch (*DataBits) {
+ case 0:
+ *DataBits = 8;
+ case 8:
+ LineControl |= PL011_UARTLCR_H_WLEN_8;
+ break;
+ case 7:
+ LineControl |= PL011_UARTLCR_H_WLEN_7;
+ break;
+ case 6:
+ LineControl |= PL011_UARTLCR_H_WLEN_6;
+ break;
+ case 5:
+ LineControl |= PL011_UARTLCR_H_WLEN_5;
+ break;
+ default:
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ //
+ // Stop Bits
+ //
+ switch (*StopBits) {
+ case DefaultStopBits:
+ *StopBits = OneStopBit;
+ case OneStopBit:
+ // Nothing to do. One stop bit is enabled by default.
+ break;
+ case TwoStopBits:
+ LineControl |= PL011_UARTLCR_H_STP2;
+ break;
+ case OneFiveStopBits:
+ // Only 1 or 2 stop bits are supported
+ default:
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ // Don't send the LineControl value to the PL011 yet,
+ // wait until after the Baud Rate setting.
+ // This ensures we do not mess up the UART settings halfway through
+ // in the rare case when there is an error with the Baud Rate.
+
+ //
+ // Baud Rate
+ //
+
+ // If PL011 Integer value has been defined then always ignore the BAUD rate
+ if (FixedPcdGet32 (PL011UartInteger) != 0) {
+ Integer = FixedPcdGet32 (PL011UartInteger);
+ Fractional = FixedPcdGet32 (PL011UartFractional);
+ } else {
+ // If BAUD rate is zero then replace it with the system default value
+ if (*BaudRate == 0) {
+ *BaudRate = FixedPcdGet32 (PcdSerialBaudRate);
+ if (*BaudRate == 0) {
+ return RETURN_INVALID_PARAMETER;
+ }
+ }
+ if (0 == UartClkInHz) {
+ return RETURN_INVALID_PARAMETER;
+ }
+
+ Divisor = (UartClkInHz * 4) / *BaudRate;
+ Integer = Divisor >> FRACTION_PART_SIZE_IN_BITS;
+ Fractional = Divisor & FRACTION_PART_MASK;
+ }
+
+ //
+ // If PL011 is already initialized, check the current settings
+ // and re-initialize only if the settings are different.
+ //
+ if (((MmioRead32 (UartBase + UARTCR) & PL011_UARTCR_UARTEN) != 0) &&
+ (MmioRead32 (UartBase + UARTLCR_H) == LineControl) &&
+ (MmioRead32 (UartBase + UARTIBRD) == Integer) &&
+ (MmioRead32 (UartBase + UARTFBRD) == Fractional)) {
+ // Nothing to do - already initialized with correct attributes
+ return RETURN_SUCCESS;
+ }
+
+ // Wait for the end of transmission
+ while ((MmioRead32 (UartBase + UARTFR) & PL011_UARTFR_TXFE) == 0);
+
+ // Disable UART: "The UARTLCR_H, UARTIBRD, and UARTFBRD registers must not be changed
+ // when the UART is enabled"
+ MmioWrite32 (UartBase + UARTCR, 0);
+
+ // Set Baud Rate Registers
+ MmioWrite32 (UartBase + UARTIBRD, Integer);
+ MmioWrite32 (UartBase + UARTFBRD, Fractional);
+
+ // No parity, 1 stop, no fifo, 8 data bits
+ MmioWrite32 (UartBase + UARTLCR_H, LineControl);
+
+ // Clear any pending errors
+ MmioWrite32 (UartBase + UARTECR, 0);
+
+ // Enable Tx, Rx, and UART overall
+ MmioWrite32 (UartBase + UARTCR,
+ PL011_UARTCR_RXE | PL011_UARTCR_TXE | PL011_UARTCR_UARTEN);
+
+ return RETURN_SUCCESS;
+}
+
+/**
+
+ Assert or deassert the control signals on a serial port.
+ The following control signals are set according their bit settings :
+ . Request to Send
+ . Data Terminal Ready
+
+ @param[in] UartBase UART registers base address
+ @param[in] Control The following bits are taken into account :
+ . EFI_SERIAL_REQUEST_TO_SEND : assert/deassert the
+ "Request To Send" control signal if this bit is
+ equal to one/zero.
+ . EFI_SERIAL_DATA_TERMINAL_READY : assert/deassert
+ the "Data Terminal Ready" control signal if this
+ bit is equal to one/zero.
+ . EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE : enable/disable
+ the hardware loopback if this bit is equal to
+ one/zero.
+ . EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE : not supported.
+ . EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE : enable/
+ disable the hardware flow control based on CTS (Clear
+ To Send) and RTS (Ready To Send) control signals.
+
+ @retval RETURN_SUCCESS The new control bits were set on the device.
+ @retval RETURN_UNSUPPORTED The device does not support this operation.
+
+**/
+RETURN_STATUS
+EFIAPI
+PL011UartSetControl (
+ IN UINTN UartBase,
+ IN UINT32 Control
+ )
+{
+ UINT32 Bits;
+
+ if (Control & (mInvalidControlBits)) {
+ return RETURN_UNSUPPORTED;
+ }
+
+ Bits = MmioRead32 (UartBase + UARTCR);
+
+ if (Control & EFI_SERIAL_REQUEST_TO_SEND) {
+ Bits |= PL011_UARTCR_RTS;
+ } else {
+ Bits &= ~PL011_UARTCR_RTS;
+ }
+
+ if (Control & EFI_SERIAL_DATA_TERMINAL_READY) {
+ Bits |= PL011_UARTCR_DTR;
+ } else {
+ Bits &= ~PL011_UARTCR_DTR;
+ }
+
+ if (Control & EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE) {
+ Bits |= PL011_UARTCR_LBE;
+ } else {
+ Bits &= ~PL011_UARTCR_LBE;
+ }
+
+ if (Control & EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE) {
+ Bits |= (PL011_UARTCR_CTSEN | PL011_UARTCR_RTSEN);
+ } else {
+ Bits &= ~(PL011_UARTCR_CTSEN | PL011_UARTCR_RTSEN);
+ }
+
+ MmioWrite32 (UartBase + UARTCR, Bits);
+
+ return RETURN_SUCCESS;
+}
+
+/**
+
+ Retrieve the status of the control bits on a serial device.
+
+ @param[in] UartBase UART registers base address
+ @param[out] Control Status of the control bits on a serial device :
+
+ . EFI_SERIAL_DATA_CLEAR_TO_SEND,
+ EFI_SERIAL_DATA_SET_READY,
+ EFI_SERIAL_RING_INDICATE,
+ EFI_SERIAL_CARRIER_DETECT,
+ EFI_SERIAL_REQUEST_TO_SEND,
+ EFI_SERIAL_DATA_TERMINAL_READY
+ are all related to the DTE (Data Terminal Equipment)
+ and DCE (Data Communication Equipment) modes of
+ operation of the serial device.
+ . EFI_SERIAL_INPUT_BUFFER_EMPTY : equal to one if the
+ receive buffer is empty, 0 otherwise.
+ . EFI_SERIAL_OUTPUT_BUFFER_EMPTY : equal to one if the
+ transmit buffer is empty, 0 otherwise.
+ . EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE : equal to one if
+ the hardware loopback is enabled (the ouput feeds the
+ receive buffer), 0 otherwise.
+ . EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE : equal to one if
+ a loopback is accomplished by software, 0 otherwise.
+ . EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE : equal to
+ one if the hardware flow control based on CTS (Clear
+ To Send) and RTS (Ready To Send) control signals is
+ enabled, 0 otherwise.
+
+ @retval RETURN_SUCCESS The control bits were read from the serial device.
+
+**/
+RETURN_STATUS
+EFIAPI
+PL011UartGetControl (
+ IN UINTN UartBase,
+ OUT UINT32 *Control
+ )
+{
+ UINT32 FlagRegister;
+ UINT32 ControlRegister;
+
+
+ FlagRegister = MmioRead32 (UartBase + UARTFR);
+ ControlRegister = MmioRead32 (UartBase + UARTCR);
+
+ *Control = 0;
+
+ if ((FlagRegister & PL011_UARTFR_CTS) == PL011_UARTFR_CTS) {
+ *Control |= EFI_SERIAL_CLEAR_TO_SEND;
+ }
+
+ if ((FlagRegister & PL011_UARTFR_DSR) == PL011_UARTFR_DSR) {
+ *Control |= EFI_SERIAL_DATA_SET_READY;
+ }
+
+ if ((FlagRegister & PL011_UARTFR_RI) == PL011_UARTFR_RI) {
+ *Control |= EFI_SERIAL_RING_INDICATE;
+ }
+
+ if ((FlagRegister & PL011_UARTFR_DCD) == PL011_UARTFR_DCD) {
+ *Control |= EFI_SERIAL_CARRIER_DETECT;
+ }
+
+ if ((ControlRegister & PL011_UARTCR_RTS) == PL011_UARTCR_RTS) {
+ *Control |= EFI_SERIAL_REQUEST_TO_SEND;
+ }
+
+ if ((ControlRegister & PL011_UARTCR_DTR) == PL011_UARTCR_DTR) {
+ *Control |= EFI_SERIAL_DATA_TERMINAL_READY;
+ }
+
+ if ((FlagRegister & PL011_UARTFR_RXFE) == PL011_UARTFR_RXFE) {
+ *Control |= EFI_SERIAL_INPUT_BUFFER_EMPTY;
+ }
+
+ if ((FlagRegister & PL011_UARTFR_TXFE) == PL011_UARTFR_TXFE) {
+ *Control |= EFI_SERIAL_OUTPUT_BUFFER_EMPTY;
+ }
+
+ if ((ControlRegister & (PL011_UARTCR_CTSEN | PL011_UARTCR_RTSEN))
+ == (PL011_UARTCR_CTSEN | PL011_UARTCR_RTSEN)) {
+ *Control |= EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE;
+ }
+
+ if ((ControlRegister & PL011_UARTCR_LBE) == PL011_UARTCR_LBE) {
+ *Control |= EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE;
+ }
+
+ return RETURN_SUCCESS;
+}
+
+/**
+ Write data to serial device.
+
+ @param Buffer Point of data buffer which need to be written.
+ @param NumberOfBytes Number of output bytes which are cached in Buffer.
+
+ @retval 0 Write data failed.
+ @retval !0 Actual number of bytes written to serial device.
+
+**/
+UINTN
+EFIAPI
+PL011UartWrite (
+ IN UINTN UartBase,
+ IN UINT8 *Buffer,
+ IN UINTN NumberOfBytes
+ )
+{
+ UINT8* CONST Final = &Buffer[NumberOfBytes];
+
+ while (Buffer < Final) {
+ // Wait until UART able to accept another char
+ while ((MmioRead32 (UartBase + UARTFR) & UART_TX_FULL_FLAG_MASK));
+
+ MmioWrite8 (UartBase + UARTDR, *Buffer++);
+ }
+
+ return NumberOfBytes;
+}
+
+/**
+ Read data from serial device and save the data in buffer.
+
+ @param Buffer Point of data buffer which need to be written.
+ @param NumberOfBytes Number of output bytes which are cached in Buffer.
+
+ @retval 0 Read data failed.
+ @retval !0 Actual number of bytes read from serial device.
+
+**/
+UINTN
+EFIAPI
+PL011UartRead (
+ IN UINTN UartBase,
+ OUT UINT8 *Buffer,
+ IN UINTN NumberOfBytes
+ )
+{
+ UINTN Count;
+
+ for (Count = 0; Count < NumberOfBytes; Count++, Buffer++) {
+ while ((MmioRead32 (UartBase + UARTFR) & UART_RX_EMPTY_FLAG_MASK) != 0);
+ *Buffer = MmioRead8 (UartBase + UARTDR);
+ }
+
+ return NumberOfBytes;
+}
+
+/**
+ Check to see if any data is available to be read from the debug device.
+
+ @retval TRUE At least one byte of data is available to be read
+ @retval FALSE No data is available to be read
+
+**/
+BOOLEAN
+EFIAPI
+PL011UartPoll (
+ IN UINTN UartBase
+ )
+{
+ return ((MmioRead32 (UartBase + UARTFR) & UART_RX_EMPTY_FLAG_MASK) == 0);
+}