Merge branch 'sh/smp'

arch/sh/Kconfig

@@ -706,6 +706,13 @@ config NR_CPUS
 	  This is purely to save memory - each supported CPU adds
 	  approximately eight kilobytes to the kernel image.
 
+config HOTPLUG_CPU
+	bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
+	depends on SMP && HOTPLUG && EXPERIMENTAL
+	help
+	  Say Y here to experiment with turning CPUs off and on.  CPUs
+	  can be controlled through /sys/devices/system/cpu.
+
 source "kernel/Kconfig.preempt"
 
 config GUSA

arch/sh/boards/board-urquell.c

@@ -24,6 +24,7 @@
 #include <cpu/sh7786.h>
 #include <asm/heartbeat.h>
 #include <asm/sizes.h>
+#include <asm/smp-ops.h>
 
 /*
  * bit  1234 5678
@@ -203,6 +204,8 @@ static void __init urquell_setup(char **cmdline_p)
 	printk(KERN_INFO "Renesas Technology Corp. Urquell support.\n");
 
 	pm_power_off = urquell_power_off;
+
+	register_smp_ops(&shx3_smp_ops);
 }
 
 /*

arch/sh/boards/mach-sdk7786/setup.c

@@ -21,6 +21,7 @@
 #include <asm/heartbeat.h>
 #include <asm/sizes.h>
 #include <asm/reboot.h>
+#include <asm/smp-ops.h>
 
 static struct resource heartbeat_resource = {
 	.start		= 0x07fff8b0,
@@ -189,6 +190,8 @@ static void __init sdk7786_setup(char **cmdline_p)
 
 	machine_ops.restart = sdk7786_restart;
 	pm_power_off = sdk7786_power_off;
+
+	register_smp_ops(&shx3_smp_ops);
 }
 
 /*

arch/sh/boards/mach-x3proto/setup.c

@@ -19,6 +19,7 @@
 #include <linux/usb/r8a66597.h>
 #include <linux/usb/m66592.h>
 #include <asm/ilsel.h>
+#include <asm/smp-ops.h>
 
 static struct resource heartbeat_resources[] = {
 	[0] = {
@@ -152,7 +153,13 @@ static void __init x3proto_init_irq(void)
 	__raw_writel(__raw_readl(0xfe410000) | (1 << 21), 0xfe410000);
 }
 
+static void __init x3proto_setup(char **cmdline_p)
+{
+	register_smp_ops(&shx3_smp_ops);
+}
+
 static struct sh_machine_vector mv_x3proto __initmv = {
 	.mv_name		= "x3proto",
+	.mv_setup		= x3proto_setup,
 	.mv_init_irq		= x3proto_init_irq,
 };

arch/sh/include/asm/irq.h

@@ -1,6 +1,7 @@
 #ifndef __ASM_SH_IRQ_H
 #define __ASM_SH_IRQ_H
 
+#include <linux/cpumask.h>
 #include <asm/machvec.h>
 
 /*
@@ -50,6 +51,8 @@ static inline int generic_irq_demux(int irq)
 #define irq_demux(irq)		sh_mv.mv_irq_demux(irq)
 
 void init_IRQ(void);
+void migrate_irqs(void);
+
 asmlinkage int do_IRQ(unsigned int irq, struct pt_regs *regs);
 
 #ifdef CONFIG_IRQSTACKS

arch/sh/include/asm/processor.h

@@ -85,6 +85,10 @@ struct sh_cpuinfo {
 	struct tlb_info itlb;
 	struct tlb_info dtlb;
 
+#ifdef CONFIG_SMP
+	struct task_struct *idle;
+#endif
+
 	unsigned long flags;
 } __attribute__ ((aligned(L1_CACHE_BYTES)));
 

arch/sh/include/asm/smp-ops.h

@@ -0,0 +1,51 @@
+#ifndef __ASM_SH_SMP_OPS_H
+#define __ASM_SH_SMP_OPS_H
+
+struct plat_smp_ops {
+	void (*smp_setup)(void);
+	unsigned int (*smp_processor_id)(void);
+	void (*prepare_cpus)(unsigned int max_cpus);
+	void (*start_cpu)(unsigned int cpu, unsigned long entry_point);
+	void (*send_ipi)(unsigned int cpu, unsigned int message);
+	int (*cpu_disable)(unsigned int cpu);
+	void (*cpu_die)(unsigned int cpu);
+	void (*play_dead)(void);
+};
+
+extern struct plat_smp_ops *mp_ops;
+extern struct plat_smp_ops shx3_smp_ops;
+
+#ifdef CONFIG_SMP
+
+static inline void plat_smp_setup(void)
+{
+	BUG_ON(!mp_ops);
+	mp_ops->smp_setup();
+}
+
+static inline void play_dead(void)
+{
+	mp_ops->play_dead();
+}
+
+extern void register_smp_ops(struct plat_smp_ops *ops);
+
+#else
+
+static inline void plat_smp_setup(void)
+{
+	/* UP, nothing to do ... */
+}
+
+static inline void register_smp_ops(struct plat_smp_ops *ops)
+{
+}
+
+static inline void play_dead(void)
+{
+	BUG();
+}
+
+#endif /* CONFIG_SMP */
+
+#endif /* __ASM_SH_SMP_OPS_H */

arch/sh/include/asm/smp.h

@@ -3,15 +3,16 @@
 
 #include <linux/bitops.h>
 #include <linux/cpumask.h>
+#include <asm/smp-ops.h>
 
 #ifdef CONFIG_SMP
 
 #include <linux/spinlock.h>
 #include <asm/atomic.h>
 #include <asm/current.h>
+#include <asm/percpu.h>
 
 #define raw_smp_processor_id()	(current_thread_info()->cpu)
-#define hard_smp_processor_id()	plat_smp_processor_id()
 
 /* Map from cpu id to sequential logical cpu number. */
 extern int __cpu_number_map[NR_CPUS];
@@ -30,20 +31,43 @@ enum {
 	SMP_MSG_NR,	/* must be last */
 };
 
+DECLARE_PER_CPU(int, cpu_state);
+
 void smp_message_recv(unsigned int msg);
 void smp_timer_broadcast(const struct cpumask *mask);
 
 void local_timer_interrupt(void);
 void local_timer_setup(unsigned int cpu);
-
-void plat_smp_setup(void);
-void plat_prepare_cpus(unsigned int max_cpus);
-int plat_smp_processor_id(void);
-void plat_start_cpu(unsigned int cpu, unsigned long entry_point);
-void plat_send_ipi(unsigned int cpu, unsigned int message);
+void local_timer_stop(unsigned int cpu);
 
 void arch_send_call_function_single_ipi(int cpu);
-extern void arch_send_call_function_ipi_mask(const struct cpumask *mask);
+void arch_send_call_function_ipi_mask(const struct cpumask *mask);
+
+void native_play_dead(void);
+void native_cpu_die(unsigned int cpu);
+int native_cpu_disable(unsigned int cpu);
+
+#ifdef CONFIG_HOTPLUG_CPU
+void play_dead_common(void);
+extern int __cpu_disable(void);
+
+static inline void __cpu_die(unsigned int cpu)
+{
+	extern struct plat_smp_ops *mp_ops;     /* private */
+
+	mp_ops->cpu_die(cpu);
+}
+#endif
+
+static inline int hard_smp_processor_id(void)
+{
+	extern struct plat_smp_ops *mp_ops;	/* private */
+
+	if (!mp_ops)
+		return 0;	/* boot CPU */
+
+	return mp_ops->smp_processor_id();
+}
 
 #else
 

arch/sh/kernel/cpu/sh4a/smp-shx3.c

@@ -1,24 +1,30 @@
 /*
  * SH-X3 SMP
  *
- *  Copyright (C) 2007 - 2008  Paul Mundt
+ *  Copyright (C) 2007 - 2010  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/kernel.h>
 #include <linux/cpumask.h>
 #include <linux/smp.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/cpu.h>
+#include <asm/sections.h>
 
 #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_SLEEP	0x00000004
 #define STBCR_LTSLP	0x80000000
 
 static irqreturn_t ipi_interrupt_handler(int irq, void *arg)
@@ -37,7 +43,7 @@ static irqreturn_t ipi_interrupt_handler(int irq, void *arg)
 	return IRQ_HANDLED;
 }
 
-void __init plat_smp_setup(void)
+static void shx3_smp_setup(void)
 {
 	unsigned int cpu = 0;
 	int i, num;
@@ -63,7 +69,7 @@ void __init plat_smp_setup(void)
         printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num);
 }
 
-void __init plat_prepare_cpus(unsigned int max_cpus)
+static void shx3_prepare_cpus(unsigned int max_cpus)
 {
 	int i;
 
@@ -74,9 +80,12 @@ void __init plat_prepare_cpus(unsigned int max_cpus)
 	for (i = 0; i < SMP_MSG_NR; i++)
 		request_irq(104 + i, ipi_interrupt_handler,
 			    IRQF_DISABLED | IRQF_PERCPU, "IPI", (void *)(long)i);
+
+	for (i = 0; i < max_cpus; i++)
+		set_cpu_present(i, true);
 }
 
-void plat_start_cpu(unsigned int cpu, unsigned long entry_point)
+static void shx3_start_cpu(unsigned int cpu, unsigned long entry_point)
 {
 	if (__in_29bit_mode())
 		__raw_writel(entry_point, RESET_REG(cpu));
@@ -93,16 +102,65 @@ void plat_start_cpu(unsigned int cpu, unsigned long entry_point)
 	__raw_writel(STBCR_RESET | STBCR_LTSLP, STBCR_REG(cpu));
 }
 
-int plat_smp_processor_id(void)
+static unsigned int shx3_smp_processor_id(void)
 {
 	return __raw_readl(0xff000048); /* CPIDR */
 }
 
-void plat_send_ipi(unsigned int cpu, unsigned int message)
+static void shx3_send_ipi(unsigned int cpu, unsigned int message)
 {
 	unsigned long addr = 0xfe410070 + (cpu * 4);
 
 	BUG_ON(cpu >= 4);
 
 	__raw_writel(1 << (message << 2), addr); /* C0INTICI..CnINTICI */
 }
+
+static void shx3_update_boot_vector(unsigned int cpu)
+{
+	__raw_writel(STBCR_MSTP, STBCR_REG(cpu));
+	while (!(__raw_readl(STBCR_REG(cpu)) & STBCR_MSTP))
+		cpu_relax();
+	__raw_writel(STBCR_RESET, STBCR_REG(cpu));
+}
+
+static int __cpuinit
+shx3_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+	unsigned int cpu = (unsigned int)hcpu;
+
+	switch (action) {
+	case CPU_UP_PREPARE:
+		shx3_update_boot_vector(cpu);
+		break;
+	case CPU_ONLINE:
+		pr_info("CPU %u is now online\n", cpu);
+		break;
+	case CPU_DEAD:
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata shx3_cpu_notifier = {
+	.notifier_call		= shx3_cpu_callback,
+};
+
+static int __cpuinit register_shx3_cpu_notifier(void)
+{
+	register_hotcpu_notifier(&shx3_cpu_notifier);
+	return 0;
+}
+late_initcall(register_shx3_cpu_notifier);
+
+struct plat_smp_ops shx3_smp_ops = {
+	.smp_setup		= shx3_smp_setup,
+	.prepare_cpus		= shx3_prepare_cpus,
+	.start_cpu		= shx3_start_cpu,
+	.smp_processor_id	= shx3_smp_processor_id,
+	.send_ipi		= shx3_send_ipi,
+	.cpu_die		= native_cpu_die,
+	.cpu_disable		= native_cpu_disable,
+	.play_dead		= native_play_dead,
+};

arch/sh/kernel/idle.c

@@ -19,6 +19,7 @@
 #include <asm/pgalloc.h>
 #include <asm/system.h>
 #include <asm/atomic.h>
+#include <asm/smp.h>
 
 void (*pm_idle)(void) = NULL;
 
@@ -89,10 +90,13 @@ void cpu_idle(void)
 	while (1) {
 		tick_nohz_stop_sched_tick(1);
 
-		while (!need_resched() && cpu_online(cpu)) {
+		while (!need_resched()) {
 			check_pgt_cache();
 			rmb();
 
+			if (cpu_is_offline(cpu))
+				play_dead();
+
 			local_irq_disable();
 			/* Don't trace irqs off for idle */
 			stop_critical_timings();
@@ -133,7 +137,7 @@ static void do_nothing(void *unused)
 void stop_this_cpu(void *unused)
 {
 	local_irq_disable();
-	cpu_clear(smp_processor_id(), cpu_online_map);
+	set_cpu_online(smp_processor_id(), false);
 
 	for (;;)
 		cpu_sleep();