ARM: mach-shmobile: SMP base support

Add SMP base support for R-Mobile / SH-Mobile processors.

This patch contains all base code to support CONFIG_SMP
regardless of ARCH_SHMOBILE processor type. Both local timer
and CPU hotplug are supported, but no processor specific
code is included.

At this point only the default behavior is in place, so
a single core will always be used even though CONFIG_SMP
is enabled on multicore systems.

The SMP Kconfig entry for arch/arm/Kconfig is excluded from
this patch to simplify merging.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Magnus Damm 2010-12-14 16:56:55 +09:00 committed by Paul Mundt
parent 09dd7ded60
commit 1c51ed4fb9
8 changed files with 194 additions and 0 deletions

View File

@ -11,6 +11,11 @@ obj-$(CONFIG_ARCH_SH7377) += setup-sh7377.o clock-sh7377.o intc-sh7377.o
obj-$(CONFIG_ARCH_SH7372) += setup-sh7372.o clock-sh7372.o intc-sh7372.o
obj-$(CONFIG_ARCH_SH73A0) += setup-sh73a0.o clock-sh73a0.o
# SMP objects
smp-y := platsmp.o headsmp.o
smp-$(CONFIG_HOTPLUG_CPU) += hotplug.o
smp-$(CONFIG_LOCAL_TIMERS) += localtimer.o
# Pinmux setup
pfc-y :=
pfc-$(CONFIG_ARCH_SH7367) += pfc-sh7367.o
@ -26,4 +31,5 @@ obj-$(CONFIG_MACH_AG5EVM) += board-ag5evm.o
obj-$(CONFIG_MACH_MACKEREL) += board-mackerel.o
# Framework support
obj-$(CONFIG_SMP) += $(smp-y)
obj-$(CONFIG_GENERIC_GPIO) += $(pfc-y)

View File

@ -0,0 +1,26 @@
/*
* SMP support for R-Mobile / SH-Mobile
*
* Copyright (C) 2010 Magnus Damm
* Copyright (C) 2010 Takashi Yoshii
*
* Based on vexpress, Copyright (c) 2003 ARM Limited, 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/linkage.h>
#include <linux/init.h>
__INIT
/*
* Reset vector for secondary CPUs.
* This will be mapped at address 0 by SBAR register.
* We need _long_ jump to the physical address.
*/
.align 12
ENTRY(shmobile_secondary_vector)
ldr pc, 1f
1: .long secondary_startup - CONFIG_PAGE_OFFSET + CONFIG_MEMORY_START

View File

@ -0,0 +1,41 @@
/*
* SMP support for R-Mobile / SH-Mobile
*
* Copyright (C) 2010 Magnus Damm
*
* Based on realview, 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/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
int platform_cpu_kill(unsigned int cpu)
{
return 1;
}
void platform_cpu_die(unsigned int cpu)
{
while (1) {
/*
* here's the WFI
*/
asm(".word 0xe320f003\n"
:
:
: "memory", "cc");
}
}
int platform_cpu_disable(unsigned int cpu)
{
/*
* we don't allow CPU 0 to be shutdown (it is still too special
* e.g. clock tick interrupts)
*/
return cpu == 0 ? -EPERM : 0;
}

View File

@ -3,6 +3,7 @@
extern struct sys_timer shmobile_timer;
extern void shmobile_setup_console(void);
extern void shmobile_secondary_vector(void);
struct clk;
extern int clk_init(void);

View File

@ -17,6 +17,12 @@
#include <mach/hardware.h>
#include <mach/irqs.h>
.macro test_for_ipi, irqnr, irqstat, base, tmp
.endm
.macro test_for_ltirq, irqnr, irqstat, base, tmp
.endm
.macro disable_fiq
.endm

View File

@ -0,0 +1,16 @@
#ifndef __MACH_SMP_H
#define __MACH_SMP_H
#include <asm/hardware/gic.h>
#include <asm/smp_mpidr.h>
/*
* We use IRQ1 as the IPI
*/
static inline void smp_cross_call(const struct cpumask *mask)
{
#if defined(CONFIG_ARM_GIC)
gic_raise_softirq(mask, 1);
#endif
}
#endif

View File

@ -0,0 +1,25 @@
/*
* SMP support for R-Mobile / SH-Mobile - local timer portion
*
* Copyright (C) 2010 Magnus Damm
*
* Based on vexpress, 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/smp.h>
#include <linux/clockchips.h>
#include <asm/smp_twd.h>
#include <asm/localtimer.h>
/*
* Setup the local clock events for a CPU.
*/
void __cpuinit local_timer_setup(struct clock_event_device *evt)
{
evt->irq = 29;
twd_timer_setup(evt);
}

View File

@ -0,0 +1,73 @@
/*
* SMP support for R-Mobile / SH-Mobile
*
* Copyright (C) 2010 Magnus Damm
*
* Based on vexpress, 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/smp.h>
#include <linux/io.h>
#include <asm/localtimer.h>
static unsigned int __init shmobile_smp_get_core_count(void)
{
return 1;
}
static void __init shmobile_smp_prepare_cpus(void)
{
/* do nothing for now */
}
void __cpuinit platform_secondary_init(unsigned int cpu)
{
trace_hardirqs_off();
}
int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle)
{
return -ENOSYS;
}
void __init smp_init_cpus(void)
{
unsigned int ncores = shmobile_smp_get_core_count();
unsigned int i;
for (i = 0; i < ncores; i++)
set_cpu_possible(i, true);
}
void __init smp_prepare_cpus(unsigned int max_cpus)
{
unsigned int ncores = shmobile_smp_get_core_count();
unsigned int cpu = smp_processor_id();
int i;
smp_store_cpu_info(cpu);
if (max_cpus > ncores)
max_cpus = ncores;
for (i = 0; i < max_cpus; i++)
set_cpu_present(i, true);
if (max_cpus > 1) {
shmobile_smp_prepare_cpus();
/*
* Enable the local timer or broadcast device for the
* boot CPU, but only if we have more than one CPU.
*/
percpu_timer_setup();
}
}