linux_dsm_epyc7002/arch/powerpc/kernel/dbell.c
Kumar Gala 620165f971 powerpc: Add support for using doorbells for SMP IPI
The e500mc supports the new msgsnd/doorbell mechanisms that were added in
the Power ISA 2.05 architecture.  We use the normal level doorbell for
doing SMP IPIs at this point.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-02-23 15:53:03 +11:00

45 lines
1.0 KiB
C

/*
* Author: Kumar Gala <galak@kernel.crashing.org>
*
* Copyright 2009 Freescale Semiconductor Inc.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/smp.h>
#include <linux/threads.h>
#include <asm/dbell.h>
#ifdef CONFIG_SMP
unsigned long dbell_smp_message[NR_CPUS];
void smp_dbell_message_pass(int target, int msg)
{
int i;
if(target < NR_CPUS) {
set_bit(msg, &dbell_smp_message[target]);
ppc_msgsnd(PPC_DBELL, 0, target);
}
else if(target == MSG_ALL_BUT_SELF) {
for_each_online_cpu(i) {
if (i == smp_processor_id())
continue;
set_bit(msg, &dbell_smp_message[i]);
ppc_msgsnd(PPC_DBELL, 0, i);
}
}
else { /* target == MSG_ALL */
for_each_online_cpu(i)
set_bit(msg, &dbell_smp_message[i]);
ppc_msgsnd(PPC_DBELL, PPC_DBELL_MSG_BRDCAST, 0);
}
}
#endif