kernel/arch/arm/common/krait-l2-accessors.c

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2024-07-22 17:22:30 +08:00
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2018, The Linux Foundation. All rights reserved.
#include <linux/spinlock.h>
#include <linux/export.h>
#include <asm/barrier.h>
#include <asm/krait-l2-accessors.h>
static DEFINE_RAW_SPINLOCK(krait_l2_lock);
void krait_set_l2_indirect_reg(u32 addr, u32 val)
{
unsigned long flags;
raw_spin_lock_irqsave(&krait_l2_lock, flags);
/*
* Select the L2 window by poking l2cpselr, then write to the window
* via l2cpdr.
*/
asm volatile ("mcr p15, 3, %0, c15, c0, 6 @ l2cpselr" : : "r" (addr));
isb();
asm volatile ("mcr p15, 3, %0, c15, c0, 7 @ l2cpdr" : : "r" (val));
isb();
raw_spin_unlock_irqrestore(&krait_l2_lock, flags);
}
EXPORT_SYMBOL(krait_set_l2_indirect_reg);
u32 krait_get_l2_indirect_reg(u32 addr)
{
u32 val;
unsigned long flags;
raw_spin_lock_irqsave(&krait_l2_lock, flags);
/*
* Select the L2 window by poking l2cpselr, then read from the window
* via l2cpdr.
*/
asm volatile ("mcr p15, 3, %0, c15, c0, 6 @ l2cpselr" : : "r" (addr));
isb();
asm volatile ("mrc p15, 3, %0, c15, c0, 7 @ l2cpdr" : "=r" (val));
raw_spin_unlock_irqrestore(&krait_l2_lock, flags);
return val;
}
EXPORT_SYMBOL(krait_get_l2_indirect_reg);