arm-trusted-firmware/plat/common/aarch64/platform_helpers.S
Juan Castillo 53fdcebd6d Call platform_is_primary_cpu() only from reset handler
The purpose of platform_is_primary_cpu() is to determine after reset
(BL1 or BL3-1 with reset handler) if the current CPU must follow the
cold boot path (primary CPU), or wait in a safe state (secondary CPU)
until the primary CPU has finished the system initialization.

This patch removes redundant calls to platform_is_primary_cpu() in
subsequent bootloader entrypoints since the reset handler already
guarantees that code is executed exclusively on the primary CPU.

Additionally, this patch removes the weak definition of
platform_is_primary_cpu(), so the implementation of this function
becomes mandatory. Removing the weak symbol avoids other
bootloaders accidentally picking up an invalid definition in case the
porting layer makes the real function available only to BL1.

The define PRIMARY_CPU is no longer mandatory in the platform porting
because platform_is_primary_cpu() hides the implementation details
(for instance, there may be platforms that report the primary CPU in
a system register). The primary CPU definition in FVP has been moved
to fvp_def.h.

The porting guide has been updated accordingly.

Fixes ARM-software/tf-issues#219

Change-Id: If675a1de8e8d25122b7fef147cb238d939f90b5e
2014-08-01 09:39:50 +01:00

86 lines
3 KiB
ArmAsm

/*
* Copyright (c) 2013-2014, ARM Limited and Contributors. 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
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <arch.h>
#include <asm_macros.S>
#include <platform_def.h>
.weak platform_get_core_pos
.weak platform_check_mpidr
.weak plat_report_exception
.weak plat_crash_console_init
.weak plat_crash_console_putc
/* -----------------------------------------------------
* int platform_get_core_pos(int mpidr);
* With this function: CorePos = (ClusterId * 4) +
* CoreId
* -----------------------------------------------------
*/
func platform_get_core_pos
and x1, x0, #MPIDR_CPU_MASK
and x0, x0, #MPIDR_CLUSTER_MASK
add x0, x1, x0, LSR #6
ret
/* -----------------------------------------------------
* Placeholder function which should be redefined by
* each platform.
* -----------------------------------------------------
*/
func platform_check_mpidr
mov x0, xzr
ret
/* -----------------------------------------------------
* Placeholder function which should be redefined by
* each platform.
* -----------------------------------------------------
*/
func plat_report_exception
ret
/* -----------------------------------------------------
* Placeholder function which should be redefined by
* each platform.
* -----------------------------------------------------
*/
func plat_crash_console_init
mov x0, #0
ret
/* -----------------------------------------------------
* Placeholder function which should be redefined by
* each platform.
* -----------------------------------------------------
*/
func plat_crash_console_putc
ret