krait-l2-accessors.c (1213B)
1// SPDX-License-Identifier: GPL-2.0 2// Copyright (c) 2018, The Linux Foundation. All rights reserved. 3 4#include <linux/spinlock.h> 5#include <linux/export.h> 6 7#include <asm/barrier.h> 8#include <asm/krait-l2-accessors.h> 9 10static DEFINE_RAW_SPINLOCK(krait_l2_lock); 11 12void krait_set_l2_indirect_reg(u32 addr, u32 val) 13{ 14 unsigned long flags; 15 16 raw_spin_lock_irqsave(&krait_l2_lock, flags); 17 /* 18 * Select the L2 window by poking l2cpselr, then write to the window 19 * via l2cpdr. 20 */ 21 asm volatile ("mcr p15, 3, %0, c15, c0, 6 @ l2cpselr" : : "r" (addr)); 22 isb(); 23 asm volatile ("mcr p15, 3, %0, c15, c0, 7 @ l2cpdr" : : "r" (val)); 24 isb(); 25 26 raw_spin_unlock_irqrestore(&krait_l2_lock, flags); 27} 28EXPORT_SYMBOL(krait_set_l2_indirect_reg); 29 30u32 krait_get_l2_indirect_reg(u32 addr) 31{ 32 u32 val; 33 unsigned long flags; 34 35 raw_spin_lock_irqsave(&krait_l2_lock, flags); 36 /* 37 * Select the L2 window by poking l2cpselr, then read from the window 38 * via l2cpdr. 39 */ 40 asm volatile ("mcr p15, 3, %0, c15, c0, 6 @ l2cpselr" : : "r" (addr)); 41 isb(); 42 asm volatile ("mrc p15, 3, %0, c15, c0, 7 @ l2cpdr" : "=r" (val)); 43 44 raw_spin_unlock_irqrestore(&krait_l2_lock, flags); 45 46 return val; 47} 48EXPORT_SYMBOL(krait_get_l2_indirect_reg);