arch/arm/mach-k3/r5/common.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * K3: R5 Common Architecture initialization
 *
 * Copyright (C) 2023 Texas Instruments Incorporated - https://www.ti.com/
 */

#include <linux/types.h>
#include <asm/hardware.h>
#include <asm/io.h>

#include "../common.h"

void disable_linefill_optimization(void)
{
	u32 actlr;

	/*
	 * On K3 devices there are 2 conditions where R5F can deadlock:
	 * 1.When software is performing series of store operations to
	 *   cacheable write back/write allocate memory region and later
	 *   on software execute barrier operation (DSB or DMB). R5F may
	 *   hang at the barrier instruction.
	 * 2.When software is performing a mix of load and store operations
	 *   within a tight loop and store operations are all writing to
	 *   cacheable write back/write allocates memory regions, R5F may
	 *   hang at one of the load instruction.
	 *
	 * To avoid the above two conditions disable linefill optimization
	 * inside Cortex R5F.
	 */
	asm("mrc p15, 0, %0, c1, c0, 1" : "=r" (actlr));
	actlr |= (1 << 13); /* Set DLFO bit  */
	asm("mcr p15, 0, %0, c1, c0, 1" : : "r" (actlr));
}