/* * SMP Support for A2 platforms * * Copyright 2007 Benjamin Herrenschmidt, IBM Corp. * * 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/cpumask.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/of.h> #include <linux/smp.h> #include <asm/dbell.h> #include <asm/machdep.h> #include <asm/xics.h> #include "ics.h" #include "wsp.h" static void smp_a2_setup_cpu(int cpu) { doorbell_setup_this_cpu(); if (cpu != boot_cpuid) xics_setup_cpu(); } int smp_a2_kick_cpu(int nr) { const char *enable_method; struct device_node *np; int thr_idx; if (nr < 0 || nr >= NR_CPUS) return -ENOENT; np = of_get_cpu_node(nr, &thr_idx); if (!np) return -ENODEV; enable_method = of_get_property(np, "enable-method", NULL); pr_devel("CPU%d has enable-method: \"%s\"\n", nr, enable_method); if (!enable_method) { printk(KERN_ERR "CPU%d has no enable-method\n", nr); return -ENOENT; } else if (strcmp(enable_method, "ibm,a2-scom") == 0) { if (a2_scom_startup_cpu(nr, thr_idx, np)) return -1; } else { printk(KERN_ERR "CPU%d: Don't understand enable-method \"%s\"\n", nr, enable_method); return -EINVAL; } /* * The processor is currently spinning, waiting for the * cpu_start field to become non-zero After we set cpu_start, * the processor will continue on to secondary_start */ paca[nr].cpu_start = 1; return 0; } static int __init smp_a2_probe(void) { return num_possible_cpus(); } static struct smp_ops_t a2_smp_ops = { .message_pass = NULL, /* Use smp_muxed_ipi_message_pass */ .cause_ipi = doorbell_cause_ipi, .probe = smp_a2_probe, .kick_cpu = smp_a2_kick_cpu, .setup_cpu = smp_a2_setup_cpu, }; void __init a2_setup_smp(void) { smp_ops = &a2_smp_ops; }