mirror of https://gitee.com/openkylin/linux.git
89 lines
1.9 KiB
C
89 lines
1.9 KiB
C
/*
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* SMP Support for A2 platforms
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*
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* Copyright 2007 Benjamin Herrenschmidt, IBM Corp.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*
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*/
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#include <linux/cpumask.h>
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#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/of.h>
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#include <linux/smp.h>
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#include <asm/dbell.h>
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#include <asm/machdep.h>
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#include <asm/xics.h>
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#include "ics.h"
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#include "wsp.h"
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static void smp_a2_setup_cpu(int cpu)
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{
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doorbell_setup_this_cpu();
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if (cpu != boot_cpuid)
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xics_setup_cpu();
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}
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int smp_a2_kick_cpu(int nr)
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{
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const char *enable_method;
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struct device_node *np;
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int thr_idx;
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if (nr < 0 || nr >= NR_CPUS)
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return -ENOENT;
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np = of_get_cpu_node(nr, &thr_idx);
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if (!np)
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return -ENODEV;
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enable_method = of_get_property(np, "enable-method", NULL);
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pr_devel("CPU%d has enable-method: \"%s\"\n", nr, enable_method);
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if (!enable_method) {
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printk(KERN_ERR "CPU%d has no enable-method\n", nr);
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return -ENOENT;
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} else if (strcmp(enable_method, "ibm,a2-scom") == 0) {
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if (a2_scom_startup_cpu(nr, thr_idx, np))
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return -1;
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} else {
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printk(KERN_ERR "CPU%d: Don't understand enable-method \"%s\"\n",
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nr, enable_method);
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return -EINVAL;
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}
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/*
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* The processor is currently spinning, waiting for the
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* cpu_start field to become non-zero After we set cpu_start,
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* the processor will continue on to secondary_start
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*/
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paca[nr].cpu_start = 1;
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return 0;
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}
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static int __init smp_a2_probe(void)
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{
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return num_possible_cpus();
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}
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static struct smp_ops_t a2_smp_ops = {
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.message_pass = NULL, /* Use smp_muxed_ipi_message_pass */
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.cause_ipi = doorbell_cause_ipi,
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.probe = smp_a2_probe,
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.kick_cpu = smp_a2_kick_cpu,
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.setup_cpu = smp_a2_setup_cpu,
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};
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void __init a2_setup_smp(void)
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{
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smp_ops = &a2_smp_ops;
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}
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