diff options
Diffstat (limited to 'arch/mips/paravirt/paravirt-smp.c')
| -rw-r--r-- | arch/mips/paravirt/paravirt-smp.c | 143 | 
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/mips/paravirt/paravirt-smp.c b/arch/mips/paravirt/paravirt-smp.c new file mode 100644 index 00000000000..0164b0c4835 --- /dev/null +++ b/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_mask(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, +};  | 
