--- /dev/null
+/*
+ * linux/arch/arm/mach-vexpress/platsmp.c
+ *
+ * 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/init.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/jiffies.h>
+#include <linux/smp.h>
+#include <linux/io.h>
+
+#include <asm/cacheflush.h>
+#include <asm/localtimer.h>
+#include <asm/smp_scu.h>
+#include <asm/unified.h>
+
+#include <mach/ct-ca9x4.h>
+#include <mach/motherboard.h>
+#define V2M_PA_CS7 0x10000000
+
+#include "core.h"
+
+extern void vexpress_secondary_startup(void);
+
+/*
+ * control for which core is the next to come out of the secondary
+ * boot "holding pen"
+ */
+volatile int __cpuinitdata pen_release = -1;
+
+static void __iomem *scu_base_addr(void)
+{
+ return MMIO_P2V(A9_MPCORE_SCU);
+}
+
+static DEFINE_SPINLOCK(boot_lock);
+
+void __cpuinit platform_secondary_init(unsigned int cpu)
+{
+ trace_hardirqs_off();
+
+ /*
+ * if any interrupts are already enabled for the primary
+ * core (e.g. timer irq), then they will not have been enabled
+ * for us: do so
+ */
+ gic_cpu_init(0, gic_cpu_base_addr);
+
+ /*
+ * let the primary processor know we're out of the
+ * pen, then head off into the C entry point
+ */
+ pen_release = -1;
+ smp_wmb();
+
+ /*
+ * Synchronise with the boot thread.
+ */
+ spin_lock(&boot_lock);
+ spin_unlock(&boot_lock);
+}
+
+int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ unsigned long timeout;
+
+ /*
+ * Set synchronisation state between this boot processor
+ * and the secondary one
+ */
+ spin_lock(&boot_lock);
+
+ /*
+ * This is really belt and braces; we hold unintended secondary
+ * CPUs in the holding pen until we're ready for them. However,
+ * since we haven't sent them a soft interrupt, they shouldn't
+ * be there.
+ */
+ pen_release = cpu;
+ __cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release));
+ outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1));
+
+ /*
+ * Send the secondary CPU a soft interrupt, thereby causing
+ * the boot monitor to read the system wide flags register,
+ * and branch to the address found there.
+ */
+ smp_cross_call(cpumask_of(cpu));
+
+ timeout = jiffies + (1 * HZ);
+ while (time_before(jiffies, timeout)) {
+ smp_rmb();
+ if (pen_release == -1)
+ break;
+
+ udelay(10);
+ }
+
+ /*
+ * now the secondary core is starting up let it run its
+ * calibrations, then wait for it to finish
+ */
+ spin_unlock(&boot_lock);
+
+ return pen_release != -1 ? -ENOSYS : 0;
+}
+
+/*
+ * Initialise the CPU possible map early - this describes the CPUs
+ * which may be present or become present in the system.
+ */
+void __init smp_init_cpus(void)
+{
+ void __iomem *scu_base = scu_base_addr();
+ unsigned int i, ncores;
+
+ ncores = scu_base ? scu_get_core_count(scu_base) : 1;
+
+ /* sanity check */
+ if (ncores == 0) {
+ printk(KERN_ERR
+ "vexpress: strange CM count of 0? Default to 1\n");
+
+ ncores = 1;
+ }
+
+ if (ncores > NR_CPUS) {
+ printk(KERN_WARNING
+ "vexpress: no. of cores (%d) greater than configured "
+ "maximum of %d - clipping\n",
+ ncores, NR_CPUS);
+ ncores = NR_CPUS;
+ }
+
+ for (i = 0; i < ncores; i++)
+ set_cpu_possible(i, true);
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ unsigned int ncores = num_possible_cpus();
+ unsigned int cpu = smp_processor_id();
+ int i;
+
+ smp_store_cpu_info(cpu);
+
+ /*
+ * are we trying to boot more cores than exist?
+ */
+ if (max_cpus > ncores)
+ max_cpus = ncores;
+
+ /*
+ * Initialise the present map, which describes the set of CPUs
+ * actually populated at the present time.
+ */
+ for (i = 0; i < max_cpus; i++)
+ set_cpu_present(i, true);
+
+ /*
+ * Initialise the SCU if there are more than one CPU and let
+ * them know where to start.
+ */
+ if (max_cpus > 1) {
+ /*
+ * Enable the local timer or broadcast device for the
+ * boot CPU, but only if we have more than one CPU.
+ */
+ percpu_timer_setup();
+
+ scu_enable(scu_base_addr());
+
+ /*
+ * Write the address of secondary startup into the
+ * system-wide flags register. The boot monitor waits
+ * until it receives a soft interrupt, and then the
+ * secondary CPU branches to this address.
+ */
+ writel(~0, MMIO_P2V(V2M_SYS_FLAGSCLR));
+ writel(BSYM(virt_to_phys(vexpress_secondary_startup)),
+ MMIO_P2V(V2M_SYS_FLAGSSET));
+ }
+}
git://ftp.safe.ca / safe / jmp / linux-2.6 / commitdiff