linux/arch/sh/kernel/cpu/sh4a/smp-shx3.c
Paul Mundt 1a442fe02d sh: Initial SH-X3 SMP support.
This adds basic support for SH-X3 SMP (4 CPUs).

More IPI and cache debugging is necessary, mostly interfacing the
d-cache coherency and the I-cache broadcast invalidates. Only for
testing at present!

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-09-21 19:16:05 +09:00

121 lines
2.7 KiB
C

/*
* SH-X3 SMP
*
* Copyright (C) 2007 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>
void __init plat_smp_setup(void)
{
unsigned int cpu = 0;
int i, num;
cpus_clear(cpu_possible_map);
cpu_set(cpu, cpu_possible_map);
__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++) {
cpu_set(i, cpu_possible_map);
__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)
{
}
#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))
;
/* 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);
BUG_ON(message >= SMP_MSG_NR);
ctrl_outl(1 << (message << 2), addr); /* C0INTICI..CnINTICI */
}
struct ipi_data {
void (*handler)(void *);
void *arg;
unsigned int message;
};
static irqreturn_t ipi_interrupt_handler(int irq, void *arg)
{
struct ipi_data *id = 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 << (id->message << 2));
ctrl_outl(x, 0xfe410080 + offs); /* C0INTICICLR..CnINTICICLR */
id->handler(id->arg);
return IRQ_HANDLED;
}
static struct ipi_data ipi_handlers[SMP_MSG_NR];
int plat_register_ipi_handler(unsigned int message,
void (*handler)(void *), void *arg)
{
struct ipi_data *id = &ipi_handlers[message];
BUG_ON(SMP_MSG_NR >= 8);
BUG_ON(message >= SMP_MSG_NR);
id->handler = handler;
id->arg = arg;
id->message = message;
return request_irq(104 + message, ipi_interrupt_handler, 0, "IPI", id);
}