/** @file
Serial I/O Port library implementation for the HDMI I2C Debug Port
PEI Library implementation
Copyright (c) 2022, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include
#include
#include
#include
#include
#include
#include
#include
#include
extern EFI_GUID gI2cHdmiDebugHobGuid;
typedef struct {
PCH_TYPE PchType;
UINT32 ControlBits;
UINT8 I2cHdmiDebugDdcBusPinPair;
BOOLEAN IgdBusMasterReset;
} I2C_HDMI_DEBUG_PORT_CONTEXT;
I2C_HDMI_DEBUG_PORT_CONTEXT*
GetI2cHdmiDebugPortContext (
VOID
)
{
EFI_STATUS Status;
EFI_HOB_GUID_TYPE *GuidHob;
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
UINT8 I2cHdmiDebugDdcBusPinPair;
I2cHdmiDebugDdcBusPinPair = 0;
GuidHob = GetFirstGuidHob (&gI2cHdmiDebugHobGuid);
if (GuidHob == NULL) {
Context = (I2C_HDMI_DEBUG_PORT_CONTEXT *) BuildGuidHob (&gI2cHdmiDebugHobGuid, sizeof (I2C_HDMI_DEBUG_PORT_CONTEXT));
if (Context == NULL) {
return NULL;
}
ZeroMem ((VOID *) Context, sizeof (I2C_HDMI_DEBUG_PORT_CONTEXT));
Context->PchType = GetPchTypeInternal ();
Status = GetGmbusBusPinPair (
(IGFX_I2C_CHANNEL) PcdGet32 (PcdI2cHdmiDebugPortDdcI2cChannel),
&I2cHdmiDebugDdcBusPinPair
);
if (EFI_ERROR (Status)) {
I2cHdmiDebugDdcBusPinPair = 0;
}
Context->I2cHdmiDebugDdcBusPinPair = I2cHdmiDebugDdcBusPinPair;
return Context;
} else {
return GET_GUID_HOB_DATA (GuidHob);
}
}
/**
Sets the control bits on a serial device.
@param 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
)
{
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
//
// check for invalid control parameters
//
if ((Control & (~(EFI_SERIAL_REQUEST_TO_SEND |
EFI_SERIAL_DATA_TERMINAL_READY |
EFI_SERIAL_HARDWARE_LOOPBACK_ENABLE |
EFI_SERIAL_SOFTWARE_LOOPBACK_ENABLE |
EFI_SERIAL_HARDWARE_FLOW_CONTROL_ENABLE))) != 0 ) {
return EFI_UNSUPPORTED;
}
Context = GetI2cHdmiDebugPortContext ();
if (Context == NULL) {
return EFI_UNSUPPORTED;
}
Control &= (UINT32) ~(EFI_SERIAL_INPUT_BUFFER_EMPTY);
Context->ControlBits = Control;
return EFI_SUCCESS;
}
/**
Retrieve the status of the control bits on a serial device.
@param 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
)
{
EFI_STATUS Status;
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
UINT8 NumberOfBytesInFifoBuffer;
Context = GetI2cHdmiDebugPortContext ();
if (Context == NULL) {
return EFI_UNSUPPORTED;
}
Status = I2cDebugPortReadyToRead (&NumberOfBytesInFifoBuffer);
if (EFI_ERROR (Status)) {
return Status;
}
*Control = (EFI_SERIAL_CLEAR_TO_SEND | EFI_SERIAL_DATA_SET_READY |
EFI_SERIAL_CARRIER_DETECT | EFI_SERIAL_OUTPUT_BUFFER_EMPTY);
if (NumberOfBytesInFifoBuffer <= 0) {
*Control |= EFI_SERIAL_INPUT_BUFFER_EMPTY;
}
*Control |= Context->ControlBits;
return Status;
}
/**
Returns the type of PCH on the system
@retval The PCH type.
**/
PCH_TYPE
GetPchType (
VOID
)
{
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
Context = GetI2cHdmiDebugPortContext ();
if (Context == NULL) {
return PchTypeUnknown;
}
return Context->PchType;
}
/**
Returns the GPIO pin pair to use for the I2C HDMI debug port
@param[out] DdcBusPinPair - The GPIO pin pair for the I2C HDMI debug port.
@retval EFI_SUCCESS - The GPIO pin pair was successfully determined
@retval EFI_INVALID_PARAMETER - The given DDC I2C channel does not exist.
@retval EFI_UNSUPPORTED - The platform is using a PCH that is not supported yet.
**/
EFI_STATUS
GetGmbusBusPinPairForI2cDebugPort (
OUT UINT8 *DdcBusPinPair
)
{
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
Context = GetI2cHdmiDebugPortContext ();
if (Context == NULL) {
return EFI_UNSUPPORTED;
}
*DdcBusPinPair = Context->I2cHdmiDebugDdcBusPinPair;
return EFI_SUCCESS;
}
/**
Returns a flag indicating whether the IGD device bus master enable needs to
be disabled at the end of the current transaction
@retval TRUE - IGD Bus Master Enable needs to be reset
@retval FALSE - IGD Bus Master Enable does not need to be reset
**/
BOOLEAN
GetIgdBusMasterReset (
VOID
)
{
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
Context = GetI2cHdmiDebugPortContext ();
if (Context == NULL) {
return TRUE;
}
return Context->IgdBusMasterReset;
}
/**
Sets a flag indicating whether the IGD device bus master enable needs to
be disabled at the end of the current transaction
@param[in] IgdBusMasterReset - IGD device bus master enable flag
**/
VOID
SetIgdBusMasterReset (
BOOLEAN IgdBusMasterReset
)
{
I2C_HDMI_DEBUG_PORT_CONTEXT *Context;
Context = GetI2cHdmiDebugPortContext ();
if (Context == NULL) {
return;
}
Context->IgdBusMasterReset = IgdBusMasterReset;
}