SpiHc.c File Reference

#include "SpiHc.h"

Go to the source code of this file.

Functions
EFI_STATUS EFIAPI	ChipSelect (IN CONST EFI_SPI_HC_PROTOCOL *This, IN CONST EFI_SPI_PERIPHERAL *SpiPeripheral, IN BOOLEAN PinValue)
EFI_STATUS EFIAPI	Clock (IN CONST EFI_SPI_HC_PROTOCOL *This, IN CONST EFI_SPI_PERIPHERAL *SpiPeripheral, IN UINT32 *ClockHz)
EFI_STATUS EFIAPI	Transaction (IN CONST EFI_SPI_HC_PROTOCOL *This, IN EFI_SPI_BUS_TRANSACTION *BusTransaction)

Detailed Description

SPI Host Controller shell implementation, as host controller code is platform specfic.

Copyright (C) 2024 Advanced Micro Devices, Inc. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file SpiHc.c.

Function Documentation

ChipSelect()

EFI_STATUS EFIAPI ChipSelect	(	IN CONST EFI_SPI_HC_PROTOCOL *	This,
		IN CONST EFI_SPI_PERIPHERAL *	SpiPeripheral,
		IN BOOLEAN	PinValue
	)

Assert or deassert the SPI chip select.

This routine is called at TPL_NOTIFY. Update the value of the chip select line for a SPI peripheral. The SPI bus layer calls this routine either in the board layer or in the SPI controller to manipulate the chip select pin at the start and end of a SPI transaction.

Parameters

[in]	This	Pointer to an EFI_SPI_HC_PROTOCOL structure.
[in]	SpiPeripheral	The address of an EFI_SPI_PERIPHERAL data structure describing the SPI peripheral whose chip select pin is to be manipulated. The routine may access the ChipSelectParameter field to gain sufficient context to complete the operati on.
[in]	PinValue	The value to be applied to the chip select line of the SPI peripheral.

Return values

EFI_SUCCESS	The chip select was set as requested
EFI_NOT_READY	Support for the chip select is not properly initialized
EFI_INVALID_PARAMETER	The ChipSeLect value or its contents are invalid

Definition at line 38 of file SpiHc.c.

Clock()

EFI_STATUS EFIAPI Clock	(	IN CONST EFI_SPI_HC_PROTOCOL *	This,
		IN CONST EFI_SPI_PERIPHERAL *	SpiPeripheral,
		IN UINT32 *	ClockHz
	)

Set up the clock generator to produce the correct clock frequency, phase and polarity for a SPI chip.

This routine is called at TPL_NOTIFY. This routine updates the clock generator to generate the correct frequency and polarity for the SPI clock.

Parameters

[in]	This	Pointer to an EFI_SPI_HC_PROTOCOL structure.
[in]	SpiPeripheral	Pointer to a EFI_SPI_PERIPHERAL data structure from which the routine can access the ClockParameter, ClockPhase and ClockPolarity fields. The routine also has access to the names for the SPI bus and chip which can be used during debugging.
[in]	ClockHz	Pointer to the requested clock frequency. The SPI host controller will choose a supported clock frequency which is less then or equal to this value. Specify zero to turn the clock generator off. The actual clock frequency supported by the SPI host controller will be returned.

Return values

EFI_SUCCESS	The clock was set up successfully
EFI_UNSUPPORTED	The SPI controller was not able to support the frequency requested by ClockHz

Definition at line 75 of file SpiHc.c.

Transaction()

EFI_STATUS EFIAPI Transaction	(	IN CONST EFI_SPI_HC_PROTOCOL *	This,
		IN EFI_SPI_BUS_TRANSACTION *	BusTransaction
	)

Perform the SPI transaction on the SPI peripheral using the SPI host controller.

This routine is called at TPL_NOTIFY. This routine synchronously returns EFI_SUCCESS indicating that the asynchronous SPI transaction was started. The routine then waits for completion of the SPI transaction prior to returning the final transaction status.

Parameters

[in]	This	Pointer to an EFI_SPI_HC_PROTOCOL structure.
[in]	BusTransaction	Pointer to a EFI_SPI_BUS_ TRANSACTION containing the description of the SPI transaction to perform.

Return values

EFI_SUCCESS	The transaction completed successfully
EFI_BAD_BUFFER_SIZE	The BusTransaction->WriteBytes value is invalid, or the BusTransaction->ReadinBytes value is invalid
EFI_UNSUPPORTED	The BusTransaction-> Transaction Type is unsupported
EFI_DEVICE_ERROR	SPI Host Controller failed transaction

Definition at line 109 of file SpiHc.c.