From 3366e3585fbf0d40ce6f2382b544851cf4df1654 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Tue, 30 Mar 2010 12:38:01 +0900 Subject: sh: Move platform smp ops in to their own structure. This cribs the MIPS plat_smp_ops approach for wrapping up the platform ops. This will allow for mixing and matching different ops on the same platform in the future. Signed-off-by: Paul Mundt --- arch/sh/boards/board-urquell.c | 3 +++ arch/sh/boards/mach-sdk7786/setup.c | 3 +++ arch/sh/boards/mach-x3proto/setup.c | 7 +++++++ arch/sh/include/asm/smp-ops.h | 39 +++++++++++++++++++++++++++++++++++++ arch/sh/include/asm/smp.h | 18 ++++++++++------- arch/sh/kernel/cpu/sh4a/smp-shx3.c | 20 +++++++++++++------ arch/sh/kernel/localtimer.c | 2 +- arch/sh/kernel/setup.c | 2 -- arch/sh/kernel/smp.c | 24 ++++++++++++++++------- 9 files changed, 95 insertions(+), 23 deletions(-) create mode 100644 arch/sh/include/asm/smp-ops.h diff --git a/arch/sh/boards/board-urquell.c b/arch/sh/boards/board-urquell.c index a9bd6e3ee10b..d81c609decc7 100644 --- a/arch/sh/boards/board-urquell.c +++ b/arch/sh/boards/board-urquell.c @@ -24,6 +24,7 @@ #include #include #include +#include /* * 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); } /* diff --git a/arch/sh/boards/mach-sdk7786/setup.c b/arch/sh/boards/mach-sdk7786/setup.c index 0c057a93fe29..2ec1ea5cf8ef 100644 --- a/arch/sh/boards/mach-sdk7786/setup.c +++ b/arch/sh/boards/mach-sdk7786/setup.c @@ -21,6 +21,7 @@ #include #include #include +#include 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); } /* diff --git a/arch/sh/boards/mach-x3proto/setup.c b/arch/sh/boards/mach-x3proto/setup.c index e284592fd42a..102bf56befb4 100644 --- a/arch/sh/boards/mach-x3proto/setup.c +++ b/arch/sh/boards/mach-x3proto/setup.c @@ -19,6 +19,7 @@ #include #include #include +#include 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, }; diff --git a/arch/sh/include/asm/smp-ops.h b/arch/sh/include/asm/smp-ops.h new file mode 100644 index 000000000000..0581b2a4c8ce --- /dev/null +++ b/arch/sh/include/asm/smp-ops.h @@ -0,0 +1,39 @@ +#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); +}; + +extern struct plat_smp_ops shx3_smp_ops; + +#ifdef CONFIG_SMP + +static inline void plat_smp_setup(void) +{ + extern struct plat_smp_ops *mp_ops; /* private */ + + BUG_ON(!mp_ops); + mp_ops->smp_setup(); +} + +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) +{ +} + +#endif /* CONFIG_SMP */ + +#endif /* __ASM_SH_SMP_OPS_H */ diff --git a/arch/sh/include/asm/smp.h b/arch/sh/include/asm/smp.h index 53ef26ced75f..7f13d46ec8d7 100644 --- a/arch/sh/include/asm/smp.h +++ b/arch/sh/include/asm/smp.h @@ -3,6 +3,7 @@ #include #include +#include #ifdef CONFIG_SMP @@ -11,7 +12,6 @@ #include #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]; @@ -36,15 +36,19 @@ 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 arch_send_call_function_single_ipi(int cpu); extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); +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 #define hard_smp_processor_id() (0) diff --git a/arch/sh/kernel/cpu/sh4a/smp-shx3.c b/arch/sh/kernel/cpu/sh4a/smp-shx3.c index c98b4574c44e..5c5d50ccbfcd 100644 --- a/arch/sh/kernel/cpu/sh4a/smp-shx3.c +++ b/arch/sh/kernel/cpu/sh4a/smp-shx3.c @@ -1,7 +1,7 @@ /* * 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 @@ -37,7 +37,7 @@ 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 +63,7 @@ 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; @@ -76,7 +76,7 @@ void __init plat_prepare_cpus(unsigned int max_cpus) IRQF_DISABLED | IRQF_PERCPU, "IPI", (void *)(long)i); } -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)); @@ -93,12 +93,12 @@ 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); @@ -106,3 +106,11 @@ void plat_send_ipi(unsigned int cpu, unsigned int message) __raw_writel(1 << (message << 2), addr); /* C0INTICI..CnINTICI */ } + +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, +}; diff --git a/arch/sh/kernel/localtimer.c b/arch/sh/kernel/localtimer.c index 0b04e7d4a9b9..865a2f1029b1 100644 --- a/arch/sh/kernel/localtimer.c +++ b/arch/sh/kernel/localtimer.c @@ -44,7 +44,7 @@ static void dummy_timer_set_mode(enum clock_event_mode mode, { } -void __cpuinit local_timer_setup(unsigned int cpu) +void local_timer_setup(unsigned int cpu) { struct clock_event_device *clk = &per_cpu(local_clockevent, cpu); diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c index 8870d6ba64bf..29155384d5a8 100644 --- a/arch/sh/kernel/setup.c +++ b/arch/sh/kernel/setup.c @@ -459,9 +459,7 @@ void __init setup_arch(char **cmdline_p) if (likely(sh_mv.mv_setup)) sh_mv.mv_setup(cmdline_p); -#ifdef CONFIG_SMP plat_smp_setup(); -#endif } /* processor boot mode configuration */ diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 002cc612deef..2f348fda0159 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -3,7 +3,7 @@ * * SMP support for the SuperH processors. * - * Copyright (C) 2002 - 2008 Paul Mundt + * Copyright (C) 2002 - 2010 Paul Mundt * Copyright (C) 2006 - 2007 Akio Idehara * * This file is subject to the terms and conditions of the GNU General Public @@ -31,6 +31,16 @@ int __cpu_number_map[NR_CPUS]; /* Map physical to logical */ int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ +struct plat_smp_ops *mp_ops = NULL; + +void __cpuinit register_smp_ops(struct plat_smp_ops *ops) +{ + if (mp_ops) + printk(KERN_WARNING "Overriding previously set SMP ops\n"); + + mp_ops = ops; +} + static inline void __init smp_store_cpu_info(unsigned int cpu) { struct sh_cpuinfo *c = cpu_data + cpu; @@ -46,7 +56,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus) init_new_context(current, &init_mm); current_thread_info()->cpu = cpu; - plat_prepare_cpus(max_cpus); + mp_ops->prepare_cpus(max_cpus); #ifndef CONFIG_HOTPLUG_CPU init_cpu_present(&cpu_possible_map); @@ -127,7 +137,7 @@ int __cpuinit __cpu_up(unsigned int cpu) (unsigned long)&stack_start + sizeof(stack_start)); wmb(); - plat_start_cpu(cpu, (unsigned long)_stext); + mp_ops->start_cpu(cpu, (unsigned long)_stext); timeout = jiffies + HZ; while (time_before(jiffies, timeout)) { @@ -159,7 +169,7 @@ void __init smp_cpus_done(unsigned int max_cpus) void smp_send_reschedule(int cpu) { - plat_send_ipi(cpu, SMP_MSG_RESCHEDULE); + mp_ops->send_ipi(cpu, SMP_MSG_RESCHEDULE); } void smp_send_stop(void) @@ -172,12 +182,12 @@ void arch_send_call_function_ipi_mask(const struct cpumask *mask) int cpu; for_each_cpu(cpu, mask) - plat_send_ipi(cpu, SMP_MSG_FUNCTION); + mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION); } void arch_send_call_function_single_ipi(int cpu) { - plat_send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE); + mp_ops->send_ipi(cpu, SMP_MSG_FUNCTION_SINGLE); } void smp_timer_broadcast(const struct cpumask *mask) @@ -185,7 +195,7 @@ void smp_timer_broadcast(const struct cpumask *mask) int cpu; for_each_cpu(cpu, mask) - plat_send_ipi(cpu, SMP_MSG_TIMER); + mp_ops->send_ipi(cpu, SMP_MSG_TIMER); } static void ipi_timer(void) -- cgit v1.2.3 From 9e8c5be8b76b188ec5bc95b378cf67aaeba1f695 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:20:29 +0900 Subject: sh: Flag present CPUs hotpluggable in topology registration. When registering CPUs in the topology initialization ensure that all of the present CPUs are flagged as hotpluggable. Signed-off-by: Paul Mundt --- arch/sh/kernel/topology.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/sh/kernel/topology.c b/arch/sh/kernel/topology.c index 9b0b633b6c92..948fdb656933 100644 --- a/arch/sh/kernel/topology.c +++ b/arch/sh/kernel/topology.c @@ -52,7 +52,11 @@ static int __init topology_init(void) #endif for_each_present_cpu(i) { - ret = register_cpu(&per_cpu(cpu_devices, i), i); + struct cpu *c = &per_cpu(cpu_devices, i); + + c->hotpluggable = 1; + + ret = register_cpu(c, i); if (unlikely(ret)) printk(KERN_WARNING "%s: register_cpu %d failed (%d)\n", __func__, i, ret); -- cgit v1.2.3 From c9f4a3f53b5d61f86eae3512abdf948878ca3498 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:35:44 +0900 Subject: sh: arch/sh/kernel/setup.c needs asm/smp.h. With the platform ops migration, the definitions still need to be included in the CONFIG_SMP=n case, so make the asm/smp.h include explicit. Signed-off-by: Paul Mundt --- arch/sh/kernel/setup.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c index 29155384d5a8..14735d5ede52 100644 --- a/arch/sh/kernel/setup.c +++ b/arch/sh/kernel/setup.c @@ -39,6 +39,7 @@ #include #include #include +#include #include /* -- cgit v1.2.3 From f0ccf2770f523bd4fc436886a38e499f9ec95c0e Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:39:50 +0900 Subject: sh: convert online CPU map twiddling to cpumask. This converts from cpu_set() for the online map to set_cpu_online(). The two online map modifiers were the last remaining manual map manipulation bits, with this in place everything now goes through cpumask. Signed-off-by: Paul Mundt --- arch/sh/kernel/idle.c | 2 +- arch/sh/kernel/smp.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index 273f890b17ae..204005329fe1 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -133,7 +133,7 @@ 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(); diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 2f348fda0159..cc87830ace7f 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -102,7 +102,7 @@ asmlinkage void __cpuinit start_secondary(void) smp_store_cpu_info(cpu); - cpu_set(cpu, cpu_online_map); + set_cpu_online(cpu, true); cpu_idle(); } -- cgit v1.2.3 From 7acb59eb4b5eee113eb74eeafd1e6536171eeced Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:44:04 +0900 Subject: sh: Make sure all SH-X3 cores are populated in the present CPU map. This iterates over the maximum number of CPUs we plan to support and makes sure they're all set in the present CPU map. Signed-off-by: Paul Mundt --- arch/sh/kernel/cpu/sh4a/smp-shx3.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/sh/kernel/cpu/sh4a/smp-shx3.c b/arch/sh/kernel/cpu/sh4a/smp-shx3.c index 5c5d50ccbfcd..dd245e68aa2e 100644 --- a/arch/sh/kernel/cpu/sh4a/smp-shx3.c +++ b/arch/sh/kernel/cpu/sh4a/smp-shx3.c @@ -74,6 +74,9 @@ static void shx3_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); } static void shx3_start_cpu(unsigned int cpu, unsigned long entry_point) -- cgit v1.2.3 From 9715b8c7d55912fb6f5dd9b1c084d8eefcd0d848 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:49:58 +0900 Subject: sh: provide percpu CPU states for hotplug notifiers. This provides percpu CPU states in preparation for CPU hotplug and the associated notifier chains. Signed-off-by: Paul Mundt --- arch/sh/include/asm/smp.h | 3 +++ arch/sh/kernel/smp.c | 14 ++++++++++---- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/sh/include/asm/smp.h b/arch/sh/include/asm/smp.h index 7f13d46ec8d7..da5135b2579e 100644 --- a/arch/sh/include/asm/smp.h +++ b/arch/sh/include/asm/smp.h @@ -10,6 +10,7 @@ #include #include #include +#include #define raw_smp_processor_id() (current_thread_info()->cpu) @@ -30,6 +31,8 @@ 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); diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index cc87830ace7f..4d27597c5da8 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -33,6 +33,9 @@ int __cpu_logical_map[NR_CPUS]; /* Map logical to physical */ struct plat_smp_ops *mp_ops = NULL; +/* State of each CPU */ +DEFINE_PER_CPU(int, cpu_state) = { 0 }; + void __cpuinit register_smp_ops(struct plat_smp_ops *ops) { if (mp_ops) @@ -72,11 +75,13 @@ void __devinit smp_prepare_boot_cpu(void) set_cpu_online(cpu, true); set_cpu_possible(cpu, true); + + per_cpu(cpu_state, cpu) = CPU_ONLINE; } asmlinkage void __cpuinit start_secondary(void) { - unsigned int cpu; + unsigned int cpu = smp_processor_id(); struct mm_struct *mm = &init_mm; enable_mmu(); @@ -90,12 +95,10 @@ asmlinkage void __cpuinit start_secondary(void) preempt_disable(); - notify_cpu_starting(smp_processor_id()); + notify_cpu_starting(cpu); local_irq_enable(); - cpu = smp_processor_id(); - /* Enable local timers */ local_timer_setup(cpu); calibrate_delay(); @@ -103,6 +106,7 @@ asmlinkage void __cpuinit start_secondary(void) smp_store_cpu_info(cpu); set_cpu_online(cpu, true); + per_cpu(cpu_state, cpu) = CPU_ONLINE; cpu_idle(); } @@ -127,6 +131,8 @@ int __cpuinit __cpu_up(unsigned int cpu) return PTR_ERR(tsk); } + per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; + /* Fill in data in head.S for secondary cpus */ stack_start.sp = tsk->thread.sp; stack_start.thread_info = tsk->stack; -- cgit v1.2.3 From 1cfa1e8f2c824b131612c9a70b48433998237331 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:55:01 +0900 Subject: sh: flag smp_store_cpu_info() __cpuinit. smp_store_cpu_info() is presently flagged as __init, but is called by start_secondary() which is __cpuinit, fix it up. Signed-off-by: Paul Mundt --- arch/sh/kernel/smp.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 4d27597c5da8..3711a76a18e0 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -44,7 +44,7 @@ void __cpuinit register_smp_ops(struct plat_smp_ops *ops) mp_ops = ops; } -static inline void __init smp_store_cpu_info(unsigned int cpu) +static inline void __cpuinit smp_store_cpu_info(unsigned int cpu) { struct sh_cpuinfo *c = cpu_data + cpu; @@ -66,7 +66,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus) #endif } -void __devinit smp_prepare_boot_cpu(void) +void __init smp_prepare_boot_cpu(void) { unsigned int cpu = smp_processor_id(); -- cgit v1.2.3 From 8db2bc4559639680a94d4492ae4b7ce71298a74f Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 18:59:47 +0900 Subject: sh: cache secondary CPUs idle loop. This provides a cache of the secondary CPUs idle loop for the cases where hotplug simply enters a low power state instead of resetting or powering off the core. Signed-off-by: Paul Mundt --- arch/sh/include/asm/processor.h | 4 ++++ arch/sh/kernel/smp.c | 13 +++++++++---- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/arch/sh/include/asm/processor.h b/arch/sh/include/asm/processor.h index 26b3f026eec9..0a58cb25a658 100644 --- a/arch/sh/include/asm/processor.h +++ b/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))); diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 3711a76a18e0..21e7f8a9f3e4 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -125,10 +125,15 @@ int __cpuinit __cpu_up(unsigned int cpu) struct task_struct *tsk; unsigned long timeout; - tsk = fork_idle(cpu); - if (IS_ERR(tsk)) { - printk(KERN_ERR "Failed forking idle task for cpu %d\n", cpu); - return PTR_ERR(tsk); + tsk = cpu_data[cpu].idle; + if (!tsk) { + tsk = fork_idle(cpu); + if (IS_ERR(tsk)) { + pr_err("Failed forking idle task for cpu %d\n", cpu); + return PTR_ERR(tsk); + } + + cpu_data[cpu].idle = tsk; } per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; -- cgit v1.2.3 From 763142d1efb56effe614d71185781796c4b83c78 Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 19:08:55 +0900 Subject: sh: CPU hotplug support. This adds preliminary support for CPU hotplug for SH SMP systems. Signed-off-by: Paul Mundt --- arch/sh/Kconfig | 7 +++ arch/sh/include/asm/irq.h | 3 ++ arch/sh/include/asm/smp-ops.h | 16 ++++++- arch/sh/include/asm/smp.h | 19 +++++++- arch/sh/kernel/idle.c | 6 ++- arch/sh/kernel/irq.c | 42 +++++++++++++++++ arch/sh/kernel/localtimer.c | 4 ++ arch/sh/kernel/smp.c | 103 +++++++++++++++++++++++++++++++++++++++++- 8 files changed, 194 insertions(+), 6 deletions(-) diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index ba86bfba95ac..d73bd4db5e84 100644 --- a/arch/sh/Kconfig +++ b/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 diff --git a/arch/sh/include/asm/irq.h b/arch/sh/include/asm/irq.h index 99c593b3a827..02c2f0102cfa 100644 --- a/arch/sh/include/asm/irq.h +++ b/arch/sh/include/asm/irq.h @@ -1,6 +1,7 @@ #ifndef __ASM_SH_IRQ_H #define __ASM_SH_IRQ_H +#include #include /* @@ -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 diff --git a/arch/sh/include/asm/smp-ops.h b/arch/sh/include/asm/smp-ops.h index 0581b2a4c8ce..c590f76856f1 100644 --- a/arch/sh/include/asm/smp-ops.h +++ b/arch/sh/include/asm/smp-ops.h @@ -7,20 +7,27 @@ struct plat_smp_ops { 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) { - extern struct plat_smp_ops *mp_ops; /* private */ - 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 @@ -34,6 +41,11 @@ 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 */ diff --git a/arch/sh/include/asm/smp.h b/arch/sh/include/asm/smp.h index da5135b2579e..9070d943ddde 100644 --- a/arch/sh/include/asm/smp.h +++ b/arch/sh/include/asm/smp.h @@ -38,9 +38,26 @@ void smp_timer_broadcast(const struct cpumask *mask); void local_timer_interrupt(void); void local_timer_setup(unsigned int cpu); +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) { diff --git a/arch/sh/kernel/idle.c b/arch/sh/kernel/idle.c index 204005329fe1..425d604e3a28 100644 --- a/arch/sh/kernel/idle.c +++ b/arch/sh/kernel/idle.c @@ -19,6 +19,7 @@ #include #include #include +#include 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(); diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c index f6a9319c28e2..257de1f0692b 100644 --- a/arch/sh/kernel/irq.c +++ b/arch/sh/kernel/irq.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -292,3 +293,44 @@ int __init arch_probe_nr_irqs(void) return 0; } #endif + +#ifdef CONFIG_HOTPLUG_CPU +static void route_irq(struct irq_desc *desc, unsigned int irq, unsigned int cpu) +{ + printk(KERN_INFO "IRQ%u: moving from cpu%u to cpu%u\n", + irq, desc->node, cpu); + + raw_spin_lock_irq(&desc->lock); + desc->chip->set_affinity(irq, cpumask_of(cpu)); + raw_spin_unlock_irq(&desc->lock); +} + +/* + * The CPU has been marked offline. Migrate IRQs off this CPU. If + * the affinity settings do not allow other CPUs, force them onto any + * available CPU. + */ +void migrate_irqs(void) +{ + struct irq_desc *desc; + unsigned int irq, cpu = smp_processor_id(); + + for_each_irq_desc(irq, desc) { + if (desc->node == cpu) { + unsigned int newcpu = cpumask_any_and(desc->affinity, + cpu_online_mask); + if (newcpu >= nr_cpu_ids) { + if (printk_ratelimit()) + printk(KERN_INFO "IRQ%u no longer affine to CPU%u\n", + irq, cpu); + + cpumask_setall(desc->affinity); + newcpu = cpumask_any_and(desc->affinity, + cpu_online_mask); + } + + route_irq(desc, irq, newcpu); + } + } +} +#endif diff --git a/arch/sh/kernel/localtimer.c b/arch/sh/kernel/localtimer.c index 865a2f1029b1..8bfc6dfa8b94 100644 --- a/arch/sh/kernel/localtimer.c +++ b/arch/sh/kernel/localtimer.c @@ -60,3 +60,7 @@ void local_timer_setup(unsigned int cpu) clockevents_register_device(clk); } + +void local_timer_stop(unsigned int cpu) +{ +} diff --git a/arch/sh/kernel/smp.c b/arch/sh/kernel/smp.c index 21e7f8a9f3e4..86cd6f94b53b 100644 --- a/arch/sh/kernel/smp.c +++ b/arch/sh/kernel/smp.c @@ -79,6 +79,105 @@ void __init smp_prepare_boot_cpu(void) per_cpu(cpu_state, cpu) = CPU_ONLINE; } +#ifdef CONFIG_HOTPLUG_CPU +void native_cpu_die(unsigned int cpu) +{ + unsigned int i; + + for (i = 0; i < 10; i++) { + smp_rmb(); + if (per_cpu(cpu_state, cpu) == CPU_DEAD) { + if (system_state == SYSTEM_RUNNING) + pr_info("CPU %u is now offline\n", cpu); + + return; + } + + msleep(100); + } + + pr_err("CPU %u didn't die...\n", cpu); +} + +int native_cpu_disable(unsigned int cpu) +{ + return cpu == 0 ? -EPERM : 0; +} + +void play_dead_common(void) +{ + idle_task_exit(); + irq_ctx_exit(raw_smp_processor_id()); + mb(); + + __get_cpu_var(cpu_state) = CPU_DEAD; + local_irq_disable(); +} + +void native_play_dead(void) +{ + play_dead_common(); +} + +int __cpu_disable(void) +{ + unsigned int cpu = smp_processor_id(); + struct task_struct *p; + int ret; + + ret = mp_ops->cpu_disable(cpu); + if (ret) + return ret; + + /* + * Take this CPU offline. Once we clear this, we can't return, + * and we must not schedule until we're ready to give up the cpu. + */ + set_cpu_online(cpu, false); + + /* + * OK - migrate IRQs away from this CPU + */ + migrate_irqs(); + + /* + * Stop the local timer for this CPU. + */ + local_timer_stop(cpu); + + /* + * Flush user cache and TLB mappings, and then remove this CPU + * from the vm mask set of all processes. + */ + flush_cache_all(); + local_flush_tlb_all(); + + read_lock(&tasklist_lock); + for_each_process(p) + if (p->mm) + cpumask_clear_cpu(cpu, mm_cpumask(p->mm)); + read_unlock(&tasklist_lock); + + return 0; +} +#else /* ... !CONFIG_HOTPLUG_CPU */ +int native_cpu_disable(void) +{ + return -ENOSYS; +} + +void native_cpu_die(unsigned int cpu) +{ + /* We said "no" in __cpu_disable */ + BUG(); +} + +void native_play_dead(void) +{ + BUG(); +} +#endif + asmlinkage void __cpuinit start_secondary(void) { unsigned int cpu = smp_processor_id(); @@ -88,8 +187,8 @@ asmlinkage void __cpuinit start_secondary(void) atomic_inc(&mm->mm_count); atomic_inc(&mm->mm_users); current->active_mm = mm; - BUG_ON(current->mm); enter_lazy_tlb(mm, current); + local_flush_tlb_all(); per_cpu_trap_init(); @@ -156,6 +255,7 @@ int __cpuinit __cpu_up(unsigned int cpu) break; udelay(10); + barrier(); } if (cpu_online(cpu)) @@ -270,7 +370,6 @@ static void flush_tlb_mm_ipi(void *mm) * behalf of debugees, kswapd stealing pages from another process etc). * Kanoj 07/00. */ - void flush_tlb_mm(struct mm_struct *mm) { preempt_disable(); -- cgit v1.2.3 From e7dc951eecb708d4aef18db4dbf489ba282d16ff Mon Sep 17 00:00:00 2001 From: Paul Mundt Date: Mon, 26 Apr 2010 19:09:57 +0900 Subject: sh: CPU hotplug support for SH-X3 SMP. This wires up CPU hotplug for SH-X3 SMP CPUs. Presently only secondary cores can be hotplugged given that the boot CPU has to contend with the broadcast timer. When real local timers are implemented this restriction can be lifted. Signed-off-by: Paul Mundt --- arch/sh/kernel/cpu/sh4a/smp-shx3.c | 47 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/arch/sh/kernel/cpu/sh4a/smp-shx3.c b/arch/sh/kernel/cpu/sh4a/smp-shx3.c index dd245e68aa2e..de865cac02ee 100644 --- a/arch/sh/kernel/cpu/sh4a/smp-shx3.c +++ b/arch/sh/kernel/cpu/sh4a/smp-shx3.c @@ -9,16 +9,22 @@ * for more details. */ #include +#include #include #include #include #include +#include +#include +#include +#include #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) @@ -110,10 +116,51 @@ static void shx3_send_ipi(unsigned int cpu, unsigned int message) __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, }; -- cgit v1.2.3