arch/arm/cpu/armv7/cpu.c

   1 /*
   2  * (C) Copyright 2008 Texas Insturments
   3  *
   4  * (C) Copyright 2002
   5  * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
   6  * Marius Groeger <mgroeger@sysgo.de>
   7  *
   8  * (C) Copyright 2002
   9  * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
  10  *
  11  * SPDX-License-Identifier:     GPL-2.0+
  12  */
  13
  14 /*
  15  * CPU specific code
  16  */
  17
  18 #include <common.h>
  19 #include <command.h>
  20 #include <asm/system.h>
  21 #include <asm/cache.h>
  22 #include <asm/armv7.h>
  23 #include <linux/compiler.h>
  24
  25 void __weak cpu_cache_initialization(void){}
  26
  27 int cleanup_before_linux(void)
  28 {
  29         /*
  30          * this function is called just before we call linux
  31          * it prepares the processor for linux
  32          *
  33          * we turn off caches etc ...
  34          */
  35 #ifndef CONFIG_SPL_BUILD
  36         disable_interrupts();
  37 #endif
  38
  39         /*
  40          * Turn off I-cache and invalidate it
  41          */
  42         icache_disable();
  43         invalidate_icache_all();
  44
  45         /*
  46          * turn off D-cache
  47          * dcache_disable() in turn flushes the d-cache and disables MMU
  48          */
  49         dcache_disable();
  50         v7_outer_cache_disable();
  51
  52         /*
  53          * After D-cache is flushed and before it is disabled there may
  54          * be some new valid entries brought into the cache. We are sure
  55          * that these lines are not dirty and will not affect our execution.
  56          * (because unwinding the call-stack and setting a bit in CP15 SCTRL
  57          * is all we did during this. We have not pushed anything on to the
  58          * stack. Neither have we affected any static data)
  59          * So just invalidate the entire d-cache again to avoid coherency
  60          * problems for kernel
  61          */
  62         invalidate_dcache_all();
  63
  64         /*
  65          * Some CPU need more cache attention before starting the kernel.
  66          */
  67         cpu_cache_initialization();
  68
  69         return 0;
  70 }