linux_dsm_epyc7002/arch/arm/mach-shmobile/hotplug.c
Magnus Damm 1c51ed4fb9 ARM: mach-shmobile: SMP base support
Add SMP base support for R-Mobile / SH-Mobile processors.

This patch contains all base code to support CONFIG_SMP
regardless of ARCH_SHMOBILE processor type. Both local timer
and CPU hotplug are supported, but no processor specific
code is included.

At this point only the default behavior is in place, so
a single core will always be used even though CONFIG_SMP
is enabled on multicore systems.

The SMP Kconfig entry for arch/arm/Kconfig is excluded from
this patch to simplify merging.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-12-14 18:15:44 +09:00

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C

/*
* SMP support for R-Mobile / SH-Mobile
*
* Copyright (C) 2010 Magnus Damm
*
* Based on realview, Copyright (C) 2002 ARM Ltd, All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
int platform_cpu_kill(unsigned int cpu)
{
return 1;
}
void platform_cpu_die(unsigned int cpu)
{
while (1) {
/*
* here's the WFI
*/
asm(".word 0xe320f003\n"
:
:
: "memory", "cc");
}
}
int platform_cpu_disable(unsigned int cpu)
{
/*
* we don't allow CPU 0 to be shutdown (it is still too special
* e.g. clock tick interrupts)
*/
return cpu == 0 ? -EPERM : 0;
}