linux-stable-rt/arch/sh/kernel/cpu/sh4a/smp-shx3.c

103 lines
2.4 KiB
C

/*
* SH-X3 SMP
*
* Copyright (C) 2007 - 2008 Paul Mundt
* Copyright (C) 2007 Magnus Damm
*
* 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.
*/
#include <linux/init.h>
#include <linux/cpumask.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/io.h>
static irqreturn_t ipi_interrupt_handler(int irq, void *arg)
{
unsigned int message = (unsigned int)(long)arg;
unsigned int cpu = hard_smp_processor_id();
unsigned int offs = 4 * cpu;
unsigned int x;
x = ctrl_inl(0xfe410070 + offs); /* C0INITICI..CnINTICI */
x &= (1 << (message << 2));
ctrl_outl(x, 0xfe410080 + offs); /* C0INTICICLR..CnINTICICLR */
smp_message_recv(message);
return IRQ_HANDLED;
}
void __init plat_smp_setup(void)
{
unsigned int cpu = 0;
int i, num;
init_cpu_possible(cpumask_of(cpu));
__cpu_number_map[0] = 0;
__cpu_logical_map[0] = 0;
/*
* Do this stupidly for now.. we don't have an easy way to probe
* for the total number of cores.
*/
for (i = 1, num = 0; i < NR_CPUS; i++) {
set_cpu_possible(i, true);
__cpu_number_map[i] = ++num;
__cpu_logical_map[num] = i;
}
printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num);
}
void __init plat_prepare_cpus(unsigned int max_cpus)
{
int i;
BUILD_BUG_ON(SMP_MSG_NR >= 8);
for (i = 0; i < SMP_MSG_NR; i++)
request_irq(104 + i, ipi_interrupt_handler, IRQF_DISABLED,
"IPI", (void *)(long)i);
}
#define STBCR_REG(phys_id) (0xfe400004 | (phys_id << 12))
#define RESET_REG(phys_id) (0xfe400008 | (phys_id << 12))
#define STBCR_MSTP 0x00000001
#define STBCR_RESET 0x00000002
#define STBCR_LTSLP 0x80000000
#define STBCR_AP_VAL (STBCR_RESET | STBCR_LTSLP)
void plat_start_cpu(unsigned int cpu, unsigned long entry_point)
{
ctrl_outl(entry_point, RESET_REG(cpu));
if (!(ctrl_inl(STBCR_REG(cpu)) & STBCR_MSTP))
ctrl_outl(STBCR_MSTP, STBCR_REG(cpu));
while (!(ctrl_inl(STBCR_REG(cpu)) & STBCR_MSTP))
cpu_relax();
/* Start up secondary processor by sending a reset */
ctrl_outl(STBCR_AP_VAL, STBCR_REG(cpu));
}
int plat_smp_processor_id(void)
{
return ctrl_inl(0xff000048); /* CPIDR */
}
void plat_send_ipi(unsigned int cpu, unsigned int message)
{
unsigned long addr = 0xfe410070 + (cpu * 4);
BUG_ON(cpu >= 4);
ctrl_outl(1 << (message << 2), addr); /* C0INTICI..CnINTICI */
}