audk/ArmVirtPkg/Library/FdtPL011SerialPortLib/EarlyFdtPL011SerialPortLib.c

277 lines
9.0 KiB
C

/** @file
Serial I/O Port library functions with base address discovered from FDT
Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>
Copyright (c) 2012 - 2013, ARM Ltd. All rights reserved.<BR>
Copyright (c) 2014, Linaro Ltd. All rights reserved.<BR>
Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <Base.h>
#include <Library/PcdLib.h>
#include <Library/PL011UartLib.h>
#include <Library/SerialPortLib.h>
#include <libfdt.h>
RETURN_STATUS
EFIAPI
SerialPortInitialize (
VOID
)
{
//
// This SerialPortInitialize() function is completely empty, for a number of
// reasons:
// - if we are executing from flash, it is hard to keep state (i.e., store the
// discovered base address in a global), and the most robust way to deal
// with this is to discover the base address at every Write ();
// - calls to the Write() function in this module may be issued before this
// initialization function is called: this is not a problem when the base
// address of the UART is hardcoded, and only the baud rate may be wrong,
// but if we don't know the base address yet, we may be poking into memory
// that does not tolerate being poked into;
// - SEC and PEI phases produce debug output only, so with debug disabled, no
// initialization (or device tree parsing) is performed at all.
//
// Note that this means that on *every* Write () call, the device tree will be
// parsed and the UART re-initialized. However, this is a small price to pay
// for having serial debug output on a UART with no fixed base address.
//
return RETURN_SUCCESS;
}
STATIC
UINT64
SerialPortGetBaseAddress (
VOID
)
{
UINT64 BaudRate;
UINT32 ReceiveFifoDepth;
EFI_PARITY_TYPE Parity;
UINT8 DataBits;
EFI_STOP_BITS_TYPE StopBits;
VOID *DeviceTreeBase;
INT32 Node, Prev;
INT32 Len;
CONST CHAR8 *Compatible;
CONST CHAR8 *NodeStatus;
CONST CHAR8 *CompatibleItem;
CONST UINT64 *RegProperty;
UINTN UartBase;
RETURN_STATUS Status;
DeviceTreeBase = (VOID *)(UINTN)PcdGet64 (PcdDeviceTreeInitialBaseAddress);
if ((DeviceTreeBase == NULL) || (fdt_check_header (DeviceTreeBase) != 0)) {
return 0;
}
//
// Enumerate all FDT nodes looking for a PL011 and capture its base address
//
for (Prev = 0;; Prev = Node) {
Node = fdt_next_node (DeviceTreeBase, Prev, NULL);
if (Node < 0) {
break;
}
Compatible = fdt_getprop (DeviceTreeBase, Node, "compatible", &Len);
if (Compatible == NULL) {
continue;
}
//
// Iterate over the NULL-separated items in the compatible string
//
for (CompatibleItem = Compatible; CompatibleItem < Compatible + Len;
CompatibleItem += 1 + AsciiStrLen (CompatibleItem)) {
if (AsciiStrCmp (CompatibleItem, "arm,pl011") == 0) {
NodeStatus = fdt_getprop (DeviceTreeBase, Node, "status", &Len);
if (NodeStatus != NULL && AsciiStrCmp (NodeStatus, "okay") != 0) {
continue;
}
RegProperty = fdt_getprop (DeviceTreeBase, Node, "reg", &Len);
if (Len != 16) {
return 0;
}
UartBase = (UINTN)fdt64_to_cpu (ReadUnaligned64 (RegProperty));
BaudRate = (UINTN)FixedPcdGet64 (PcdUartDefaultBaudRate);
ReceiveFifoDepth = 0; // Use the default value for Fifo depth
Parity = (EFI_PARITY_TYPE)FixedPcdGet8 (PcdUartDefaultParity);
DataBits = FixedPcdGet8 (PcdUartDefaultDataBits);
StopBits = (EFI_STOP_BITS_TYPE) FixedPcdGet8 (PcdUartDefaultStopBits);
Status = PL011UartInitializePort (
UartBase,
FixedPcdGet32 (PL011UartClkInHz),
&BaudRate,
&ReceiveFifoDepth,
&Parity,
&DataBits,
&StopBits
);
if (!EFI_ERROR (Status)) {
return UartBase;
}
}
}
}
return 0;
}
/**
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
SerialPortWrite (
IN UINT8 *Buffer,
IN UINTN NumberOfBytes
)
{
UINT64 SerialRegisterBase;
SerialRegisterBase = SerialPortGetBaseAddress ();
if (SerialRegisterBase != 0) {
return PL011UartWrite ((UINTN)SerialRegisterBase, Buffer, NumberOfBytes);
}
return 0;
}
/**
Read data from serial device and save the data in buffer.
@param Buffer Point of data buffer which need to be written.
@param NumberOfBytes Size of Buffer[].
@retval 0 Read data failed.
@retval !0 Actual number of bytes read from serial device.
**/
UINTN
EFIAPI
SerialPortRead (
OUT UINT8 *Buffer,
IN UINTN NumberOfBytes
)
{
return 0;
}
/**
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
SerialPortPoll (
VOID
)
{
return FALSE;
}
/**
Sets the control bits on a serial device.
@param[in] Control Sets the bits of Control that are settable.
@retval RETURN_SUCCESS The new control bits were set on the serial device.
@retval RETURN_UNSUPPORTED The serial device does not support this operation.
@retval RETURN_DEVICE_ERROR The serial device is not functioning correctly.
**/
RETURN_STATUS
EFIAPI
SerialPortSetControl (
IN UINT32 Control
)
{
return RETURN_UNSUPPORTED;
}
/**
Retrieve the status of the control bits on a serial device.
@param[out] Control A pointer to return the current control signals from the serial device.
@retval RETURN_SUCCESS The control bits were read from the serial device.
@retval RETURN_UNSUPPORTED The serial device does not support this operation.
@retval RETURN_DEVICE_ERROR The serial device is not functioning correctly.
**/
RETURN_STATUS
EFIAPI
SerialPortGetControl (
OUT UINT32 *Control
)
{
return RETURN_UNSUPPORTED;
}
/**
Sets the baud rate, receive FIFO depth, transmit/receive time out, parity,
data bits, and stop bits on a serial device.
@param BaudRate The requested baud rate. A BaudRate value of 0 will use the
device's default interface speed.
On output, the value actually set.
@param ReceiveFifoDepth The requested depth of the FIFO on the receive side of the
serial interface. A ReceiveFifoDepth value of 0 will use
the device's default FIFO depth.
On output, the value actually set.
@param Timeout The requested time out for a single character in microseconds.
This timeout applies to both the transmit and receive side of the
interface. A Timeout value of 0 will use the device's default time
out value.
On output, the value actually set.
@param Parity The type of parity to use on this serial device. A Parity value of
DefaultParity will use the device's default parity value.
On output, the value actually set.
@param DataBits The number of data bits to use on the serial device. A DataBits
value of 0 will use the device's default data bit setting.
On output, the value actually set.
@param StopBits The number of stop bits to use on this serial device. A StopBits
value of DefaultStopBits will use the device's default number of
stop bits.
On output, the value actually set.
@retval RETURN_SUCCESS The new attributes were set on the serial device.
@retval RETURN_UNSUPPORTED The serial device does not support this operation.
@retval RETURN_INVALID_PARAMETER One or more of the attributes has an unsupported value.
@retval RETURN_DEVICE_ERROR The serial device is not functioning correctly.
**/
RETURN_STATUS
EFIAPI
SerialPortSetAttributes (
IN OUT UINT64 *BaudRate,
IN OUT UINT32 *ReceiveFifoDepth,
IN OUT UINT32 *Timeout,
IN OUT EFI_PARITY_TYPE *Parity,
IN OUT UINT8 *DataBits,
IN OUT EFI_STOP_BITS_TYPE *StopBits
)
{
return RETURN_UNSUPPORTED;
}