arch/arm/mach-u8500/cache.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2019 Stephan Gerhold <stephan@gerhold.net>
   4  */
   5
   6 #include <common.h>
   7 #include <cpu_func.h>
   8 #include <asm/armv7.h>
   9 #include <asm/pl310.h>
  10
  11 #define PL310_WAY_MASK  0xff
  12
  13 #if !CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
  14 void enable_caches(void)
  15 {
  16         /* Enable D-cache. I-cache is already enabled in start.S */
  17         dcache_enable();
  18 }
  19 #endif
  20
  21 #ifdef CONFIG_SYS_L2_PL310
  22 void v7_outer_cache_disable(void)
  23 {
  24         struct pl310_regs *const pl310 = (struct pl310_regs *)CONFIG_SYS_PL310_BASE;
  25
  26         /*
  27          * Linux expects the L2 cache to be turned off by the bootloader.
  28          * Otherwise, it fails very early (shortly after decompressing the kernel).
  29          *
  30          * On U8500, the L2 cache can be only turned on/off from the secure world.
  31          * Instead, prevent usage of the L2 cache by locking all ways.
  32          * The kernel needs to unlock them to make the L2 cache work again.
  33          */
  34         writel(PL310_WAY_MASK, &pl310->pl310_lockdown_dbase);
  35         writel(PL310_WAY_MASK, &pl310->pl310_lockdown_ibase);
  36 }
  37 #endif