arch/arm/mach-omap2/omap-headsmp.S

   1 /*
   2  * Secondary CPU startup routine source file.
   3  *
   4  * Copyright (C) 2009 Texas Instruments, Inc.
   5  *
   6  * Author:
   7  *      Santosh Shilimkar <santosh.shilimkar@ti.com>
   8  *
   9  * Interface functions needed for the SMP. This file is based on arm
  10  * realview smp platform.
  11  * Copyright (c) 2003 ARM Limited.
  12  *
  13  * This program is free software,you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License version 2 as
  15  * published by the Free Software Foundation.
  16  */
  17
  18 #include <linux/linkage.h>
  19 #include <linux/init.h>
  20
  21 /* Physical address needed since MMU not enabled yet on secondary core */
  22 #define OMAP4_AUX_CORE_BOOT1_PA                 0x48281804
  23
  24         __INIT
  25
  26 /*
  27  * OMAP4 specific entry point for secondary CPU to jump from ROM
  28  * code.  This routine also provides a holding flag into which
  29  * secondary core is held until we're ready for it to initialise.
  30  * The primary core will update this flag using a hardware
  31  * register AuxCoreBoot0.
  32  */
  33 ENTRY(omap_secondary_startup)
  34 hold:   ldr     r12,=0x103
  35         dsb
  36         smc     #0                      @ read from AuxCoreBoot0
  37         mov     r0, r0, lsr #9
  38         mrc     p15, 0, r4, c0, c0, 5
  39         and     r4, r4, #0x0f
  40         cmp     r0, r4
  41         bne     hold
  42
  43         /*
  44          * we've been released from the wait loop,secondary_stack
  45          * should now contain the SVC stack for this core
  46          */
  47         b       secondary_startup
  48 END(omap_secondary_startup)
  49