cpu_helpers.S

/*
 * Copyright (c) 2013, ARM Limited. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of ARM nor the names of its contributors may be used
 * to endorse or promote products derived from this software without specific
 * prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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 */

#include <arch.h>

	.weak	cpu_reset_handler


	.section	aarch64_code, "ax"; .align 3

cpu_reset_handler:; .type cpu_reset_handler, %function
	mov	x19, x30 // lr

	/* ---------------------------------------------
	 * As a bare minimal enable the SMP bit.
	 * ---------------------------------------------
	 */
	bl	read_midr
	lsr	x0, x0, #MIDR_PN_SHIFT
	and	x0, x0, #MIDR_PN_MASK
	cmp	x0, #MIDR_PN_A57
	b.eq	smp_setup_begin
	cmp	x0, #MIDR_PN_A53
	b.ne	smp_setup_end
smp_setup_begin:
	bl	read_cpuectlr
	orr	x0, x0, #CPUECTLR_SMP_BIT
	bl	write_cpuectlr
smp_setup_end:
	ret	x19