linux/drivers/remoteproc/mtk_scp_ipi.c

// SPDX-License-Identifier: GPL-2.0
//
// Copyright (c) 2019 MediaTek Inc.

#include <asm/barrier.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/time64.h>
#include <linux/remoteproc/mtk_scp.h>

#include "mtk_common.h"

#define SCP_TIMEOUT_US …

/**
 * scp_ipi_register() - register an ipi function
 *
 * @scp:	mtk_scp structure
 * @id:		IPI ID
 * @handler:	IPI handler
 * @priv:	private data for IPI handler
 *
 * Register an ipi function to receive ipi interrupt from SCP.
 *
 * Return: 0 if ipi registers successfully, -error on error.
 */
int scp_ipi_register(struct mtk_scp *scp,
		     u32 id,
		     scp_ipi_handler_t handler,
		     void *priv)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * scp_ipi_unregister() - unregister an ipi function
 *
 * @scp:	mtk_scp structure
 * @id:		IPI ID
 *
 * Unregister an ipi function to receive ipi interrupt from SCP.
 */
void scp_ipi_unregister(struct mtk_scp *scp, u32 id)
{ … }
EXPORT_SYMBOL_GPL(…);

/*
 * scp_memcpy_aligned() - Copy src to dst, where dst is in SCP SRAM region.
 *
 * @dst:	Pointer to the destination buffer, should be in SCP SRAM region.
 * @src:	Pointer to the source buffer.
 * @len:	Length of the source buffer to be copied.
 *
 * Since AP access of SCP SRAM don't support byte write, this always write a
 * full word at a time, and may cause some extra bytes to be written at the
 * beginning & ending of dst.
 */
void scp_memcpy_aligned(void __iomem *dst, const void *src, unsigned int len)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * scp_ipi_lock() - Lock before operations of an IPI ID
 *
 * @scp:	mtk_scp structure
 * @id:		IPI ID
 *
 * Note: This should not be used by drivers other than mtk_scp.
 */
void scp_ipi_lock(struct mtk_scp *scp, u32 id)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * scp_ipi_unlock() - Unlock after operations of an IPI ID
 *
 * @scp:	mtk_scp structure
 * @id:		IPI ID
 *
 * Note: This should not be used by drivers other than mtk_scp.
 */
void scp_ipi_unlock(struct mtk_scp *scp, u32 id)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * scp_ipi_send() - send data from AP to scp.
 *
 * @scp:	mtk_scp structure
 * @id:		IPI ID
 * @buf:	the data buffer
 * @len:	the data buffer length
 * @wait:	number of msecs to wait for ack. 0 to skip waiting.
 *
 * This function is thread-safe. When this function returns,
 * SCP has received the data and starts the processing.
 * When the processing completes, IPI handler registered
 * by scp_ipi_register will be called in interrupt context.
 *
 * Return: 0 if sending data successfully, -error on error.
 **/
int scp_ipi_send(struct mtk_scp *scp, u32 id, void *buf, unsigned int len,
		 unsigned int wait)
{ … }
EXPORT_SYMBOL_GPL(…);

MODULE_LICENSE(…) …;
MODULE_DESCRIPTION(…) …;