Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / arch / mips / paravirt / paravirt-smp.c

diff --git a/kernel/arch/mips/paravirt/paravirt-smp.c b/kernel/arch/mips/paravirt/paravirt-smp.c
new file mode 100644 (file)
index 0000000..42181c7
--- /dev/null
+++ b/kernel/arch/mips/paravirt/paravirt-smp.c
@@ -0,0 +1,143 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2013 Cavium, Inc.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/cpumask.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+
+#include <asm/mipsregs.h>
+#include <asm/setup.h>
+#include <asm/time.h>
+#include <asm/smp.h>
+
+/*
+ * Writing the sp releases the CPU, so writes must be ordered, gp
+ * first, then sp.
+ */
+unsigned long paravirt_smp_sp[NR_CPUS];
+unsigned long paravirt_smp_gp[NR_CPUS];
+
+static int numcpus = 1;
+
+static int __init set_numcpus(char *str)
+{
+       int newval;
+
+       if (get_option(&str, &newval)) {
+               if (newval < 1 || newval >= NR_CPUS)
+                       goto bad;
+               numcpus = newval;
+               return 0;
+       }
+bad:
+       return -EINVAL;
+}
+early_param("numcpus", set_numcpus);
+
+
+static void paravirt_smp_setup(void)
+{
+       int id;
+       unsigned int cpunum = get_ebase_cpunum();
+
+       if (WARN_ON(cpunum >= NR_CPUS))
+               return;
+
+       /* The present CPUs are initially just the boot cpu (CPU 0). */
+       for (id = 0; id < NR_CPUS; id++) {
+               set_cpu_possible(id, id == 0);
+               set_cpu_present(id, id == 0);
+       }
+       __cpu_number_map[cpunum] = 0;
+       __cpu_logical_map[0] = cpunum;
+
+       for (id = 0; id < numcpus; id++) {
+               set_cpu_possible(id, true);
+               set_cpu_present(id, true);
+               __cpu_number_map[id] = id;
+               __cpu_logical_map[id] = id;
+       }
+}
+
+void irq_mbox_ipi(int cpu, unsigned int actions);
+static void paravirt_send_ipi_single(int cpu, unsigned int action)
+{
+       irq_mbox_ipi(cpu, action);
+}
+
+static void paravirt_send_ipi_mask(const struct cpumask *mask, unsigned int action)
+{
+       unsigned int cpu;
+
+       for_each_cpu(cpu, mask)
+               paravirt_send_ipi_single(cpu, action);
+}
+
+static void paravirt_init_secondary(void)
+{
+       unsigned int sr;
+
+       sr = set_c0_status(ST0_BEV);
+       write_c0_ebase((u32)ebase);
+
+       sr |= STATUSF_IP2; /* Interrupt controller on IP2 */
+       write_c0_status(sr);
+
+       irq_cpu_online();
+}
+
+static void paravirt_smp_finish(void)
+{
+       /* to generate the first CPU timer interrupt */
+       write_c0_compare(read_c0_count() + mips_hpt_frequency / HZ);
+       local_irq_enable();
+}
+
+static void paravirt_boot_secondary(int cpu, struct task_struct *idle)
+{
+       paravirt_smp_gp[cpu] = (unsigned long)task_thread_info(idle);
+       smp_wmb();
+       paravirt_smp_sp[cpu] = __KSTK_TOS(idle);
+}
+
+static irqreturn_t paravirt_reched_interrupt(int irq, void *dev_id)
+{
+       scheduler_ipi();
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t paravirt_function_interrupt(int irq, void *dev_id)
+{
+       smp_call_function_interrupt();
+       return IRQ_HANDLED;
+}
+
+static void paravirt_prepare_cpus(unsigned int max_cpus)
+{
+       if (request_irq(MIPS_IRQ_MBOX0, paravirt_reched_interrupt,
+                       IRQF_PERCPU | IRQF_NO_THREAD, "Scheduler",
+                       paravirt_reched_interrupt)) {
+               panic("Cannot request_irq for SchedulerIPI");
+       }
+       if (request_irq(MIPS_IRQ_MBOX1, paravirt_function_interrupt,
+                       IRQF_PERCPU | IRQF_NO_THREAD, "SMP-Call",
+                       paravirt_function_interrupt)) {
+               panic("Cannot request_irq for SMP-Call");
+       }
+}
+
+struct plat_smp_ops paravirt_smp_ops = {
+       .send_ipi_single        = paravirt_send_ipi_single,
+       .send_ipi_mask          = paravirt_send_ipi_mask,
+       .init_secondary         = paravirt_init_secondary,
+       .smp_finish             = paravirt_smp_finish,
+       .boot_secondary         = paravirt_boot_secondary,
+       .smp_setup              = paravirt_smp_setup,
+       .prepare_cpus           = paravirt_prepare_cpus,
+};