On Thu, Dec 02, 2010 at 05:38:24PM +0000, Russell King - ARM Linux wrote: > What if a platform, for what ever reason, wants to have 3 CPUs, > numbered 0, 2, 3 ? That's the reason why the code which sets the > possible and present maps isn't in the ARM core code - Eg, we don't > know if a platform wants to keep CPU 1 in AMP mode to run some > special software on it. > > I don't think it's worth it because I think trying to considate this > is going to cripple the code structure in the future. I don't think this is particularly worth it either: 8e511800fe64114d00b6a22c6e37a510b208785e arch/arm/include/asm/smp.h | 14 ++++++- arch/arm/kernel/smp.c | 71 ++++++++++++++++++++++++++++++++------ arch/arm/kernel/smp_scu.c | 2 +- arch/arm/mach-omap2/omap-smp.c | 67 +++--------------------------------- arch/arm/mach-realview/platsmp.c | 71 ++++--------------------------------- arch/arm/mach-s5pv310/platsmp.c | 63 ++++----------------------------- arch/arm/mach-tegra/platsmp.c | 39 ++------------------- arch/arm/mach-ux500/platsmp.c | 55 +++-------------------------- arch/arm/mach-vexpress/platsmp.c | 69 +++++------------------------------- 9 files changed, 113 insertions(+), 338 deletions(-) diff --git a/arch/arm/include/asm/smp.h b/arch/arm/include/asm/smp.h index f93d0a6..99dd48b 100644 --- a/arch/arm/include/asm/smp.h +++ b/arch/arm/include/asm/smp.h @@ -46,9 +46,14 @@ asmlinkage void do_IPI(int ipinr, struct pt_regs *regs); extern void smp_init_cpus(void); /* - * Move global data into per-processor storage. + * Initialize cpu_possible map for 0 .. CPUs. */ -extern void smp_store_cpu_info(unsigned int cpuid); +void smp_init_cpu_possible(unsigned int); + +/* + * Initialize cpu_present map for 0 .. CPUs. + */ +void smp_init_cpu_present(unsigned int); /* * Raise an IPI cross call on CPUs in callmap. @@ -73,6 +78,11 @@ asmlinkage void secondary_start_kernel(void); extern void platform_secondary_init(unsigned int cpu); /* + * Initialize cpu_possible map, and enable coherency + */ +extern void platform_smp_prepare_cpus(unsigned int); + +/* * Initial data for bringing up a secondary CPU. */ struct secondary_data { diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 4c3ed4f..46af08f 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -296,6 +296,17 @@ void __ref cpu_die(void) #endif /* CONFIG_HOTPLUG_CPU */ /* + * Called by both boot and secondaries to move global data into + * per-processor storage. + */ +static void __cpuinit smp_store_cpu_info(unsigned int cpuid) +{ + struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid); + + cpu_info->loops_per_jiffy = loops_per_jiffy; +} + +/* * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. */ @@ -353,17 +364,6 @@ asmlinkage void __cpuinit secondary_start_kernel(void) cpu_idle(); } -/* - * Called by both boot and secondaries to move global data into - * per-processor storage. - */ -void __cpuinit smp_store_cpu_info(unsigned int cpuid) -{ - struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid); - - cpu_info->loops_per_jiffy = loops_per_jiffy; -} - void __init smp_cpus_done(unsigned int max_cpus) { int cpu; @@ -386,6 +386,55 @@ void __init smp_prepare_boot_cpu(void) per_cpu(cpu_data, cpu).idle = current; } +void __init smp_init_cpu_possible(unsigned int ncores) +{ + unsigned int i; + + if (ncores > NR_CPUS) { + pr_warning("SMP: no. of cores (%u) greater than configured maximum of %u - clipping\n", + ncores, NR_CPUS); + ncores = NR_CPUS; + } + + for (i = 0; i < ncores; i++) + set_cpu_possible(i, true); +} + +void __init smp_init_cpu_present(unsigned int ncores) +{ + unsigned int i; + + for (i = 0; i < ncores; i++) + set_cpu_present(i, true); +} + +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + unsigned int ncores = num_possible_cpus(); + + smp_store_cpu_info(smp_processor_id()); + + /* + * are we trying to boot more cores than exist? + */ + if (max_cpus > ncores) + max_cpus = ncores; + + if (max_cpus > 1) { + /* + * Enable the local timer or broadcast device for the + * boot CPU, but only if we have more than one CPU. + */ + percpu_timer_setup(); + + /* + * Initialise the SCU if there are more than one CPU + * and let them know where to start. + */ + platform_smp_prepare_cpus(max_cpus); + } +} + static void send_ipi_message(const struct cpumask *mask, enum ipi_msg_type msg) { unsigned long flags; diff --git a/arch/arm/kernel/smp_scu.c b/arch/arm/kernel/smp_scu.c index 9ab4149..904b77b 100644 --- a/arch/arm/kernel/smp_scu.c +++ b/arch/arm/kernel/smp_scu.c @@ -11,8 +11,8 @@ #include <linux/init.h> #include <linux/io.h> -#include <asm/smp_scu.h> #include <asm/cacheflush.h> +#include <asm/smp_scu.h> #define SCU_CTRL 0x00 #define SCU_CONFIG 0x04 diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c index 56a8bce..a123edf 100644 --- a/arch/arm/mach-omap2/omap-smp.c +++ b/arch/arm/mach-omap2/omap-smp.c @@ -21,7 +21,6 @@ #include <linux/io.h> #include <asm/cacheflush.h> -#include <asm/localtimer.h> #include <asm/smp_scu.h> #include <mach/hardware.h> #include <mach/omap4-common.h> @@ -29,16 +28,6 @@ /* SCU base address */ static void __iomem *scu_base; -/* - * Use SCU config register to count number of cores - */ -static inline unsigned int get_core_count(void) -{ - if (scu_base) - return scu_get_core_count(scu_base); - return 1; -} - static DEFINE_SPINLOCK(boot_lock); void __cpuinit platform_secondary_init(unsigned int cpu) @@ -112,65 +101,19 @@ static void __init wakeup_secondary(void) */ void __init smp_init_cpus(void) { - unsigned int i, ncores; - /* Never released */ scu_base = ioremap(OMAP44XX_SCU_BASE, SZ_256); BUG_ON(!scu_base); - ncores = get_core_count(); - - for (i = 0; i < ncores; i++) - set_cpu_possible(i, true); + smp_init_cpu_possible(scu_get_core_count(scu_base)); } -void __init smp_prepare_cpus(unsigned int max_cpus) +void __init platform_smp_prepare_cpus(unsigned int max_cpus) { - unsigned int ncores = get_core_count(); - unsigned int cpu = smp_processor_id(); - int i; - - /* sanity check */ - if (ncores == 0) { - printk(KERN_ERR - "OMAP4: strange core count of 0? Default to 1\n"); - ncores = 1; - } - - if (ncores > NR_CPUS) { - printk(KERN_WARNING - "OMAP4: no. of cores (%d) greater than configured " - "maximum of %d - clipping\n", - ncores, NR_CPUS); - ncores = NR_CPUS; - } - smp_store_cpu_info(cpu); - - /* - * are we trying to boot more cores than exist? - */ - if (max_cpus > ncores) - max_cpus = ncores; + smp_init_cpu_present(max_cpus); /* - * Initialise the present map, which describes the set of CPUs - * actually populated at the present time. + * Wake up the secondary core using wakeup_secondary(). */ - for (i = 0; i < max_cpus; i++) - set_cpu_present(i, true); - - if (max_cpus > 1) { - /* - * Enable the local timer or broadcast device for the - * boot CPU, but only if we have more than one CPU. - */ - percpu_timer_setup(); - - /* - * Initialise the SCU and wake up the secondary core using - * wakeup_secondary(). - */ - scu_enable(scu_base); - wakeup_secondary(); - } + wakeup_secondary(); } diff --git a/arch/arm/mach-realview/platsmp.c b/arch/arm/mach-realview/platsmp.c index af3d909..b9908e4 100644 --- a/arch/arm/mach-realview/platsmp.c +++ b/arch/arm/mach-realview/platsmp.c @@ -19,7 +19,6 @@ #include <asm/cacheflush.h> #include <mach/hardware.h> #include <asm/mach-types.h> -#include <asm/localtimer.h> #include <asm/unified.h> #include <mach/board-eb.h> @@ -50,14 +49,6 @@ static void __iomem *scu_base_addr(void) return (void __iomem *)0; } -static inline unsigned int get_core_count(void) -{ - void __iomem *scu_base = scu_base_addr(); - if (scu_base) - return scu_get_core_count(scu_base); - return 1; -} - static DEFINE_SPINLOCK(boot_lock); void __cpuinit platform_secondary_init(unsigned int cpu) @@ -158,64 +149,18 @@ static void __init poke_milo(void) */ void __init smp_init_cpus(void) { - unsigned int i, ncores = get_core_count(); + void __iomem *scu_base = scu_base_addr(); + unsigned int ncores; + + ncores = scu_base ? scu_get_core_count(scu_base) : 1; - for (i = 0; i < ncores; i++) - set_cpu_possible(i, true); + smp_init_cpu_possible(ncores); } -void __init smp_prepare_cpus(unsigned int max_cpus) +void __init platform_smp_prepare_cpus(unsigned int max_cpus) { - unsigned int ncores = get_core_count(); - unsigned int cpu = smp_processor_id(); - int i; - - /* sanity check */ - if (ncores == 0) { - printk(KERN_ERR - "Realview: strange CM count of 0? Default to 1\n"); - - ncores = 1; - } - - if (ncores > NR_CPUS) { - printk(KERN_WARNING - "Realview: no. of cores (%d) greater than configured " - "maximum of %d - clipping\n", - ncores, NR_CPUS); - ncores = NR_CPUS; - } + smp_init_cpu_present(max_cpus); - smp_store_cpu_info(cpu); - - /* - * are we trying to boot more cores than exist? - */ - if (max_cpus > ncores) - max_cpus = ncores; - - /* - * Initialise the present map, which describes the set of CPUs - * actually populated at the present time. - */ - for (i = 0; i < max_cpus; i++) - set_cpu_present(i, true); - - /* - * Initialise the SCU if there are more than one CPU and let - * them know where to start. Note that, on modern versions of - * MILO, the "poke" doesn't actually do anything until each - * individual core is sent a soft interrupt to get it out of - * WFI - */ - if (max_cpus > 1) { - /* - * Enable the local timer or broadcast device for the - * boot CPU, but only if we have more than one CPU. - */ - percpu_timer_setup(); - - scu_enable(scu_base_addr()); + if (num_present_cpus() > 1) poke_milo(); - } } diff --git a/arch/arm/mach-s5pv310/platsmp.c b/arch/arm/mach-s5pv310/platsmp.c index d474426..407c825 100644 --- a/arch/arm/mach-s5pv310/platsmp.c +++ b/arch/arm/mach-s5pv310/platsmp.c @@ -22,7 +22,6 @@ #include <linux/io.h> #include <asm/cacheflush.h> -#include <asm/localtimer.h> #include <asm/smp_scu.h> #include <asm/unified.h> @@ -125,68 +124,22 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) void __init smp_init_cpus(void) { void __iomem *scu_base = scu_base_addr(); - unsigned int i, ncores; + unsigned int ncores; ncores = scu_base ? scu_get_core_count(scu_base) : 1; - /* sanity check */ - if (ncores == 0) { - printk(KERN_ERR - "S5PV310: strange CM count of 0? Default to 1\n"); - - ncores = 1; - } - - if (ncores > NR_CPUS) { - printk(KERN_WARNING - "S5PV310: no. of cores (%d) greater than configured " - "maximum of %d - clipping\n", - ncores, NR_CPUS); - ncores = NR_CPUS; - } - - for (i = 0; i < ncores; i++) - set_cpu_possible(i, true); + smp_init_cpu_possible(ncores); } -void __init smp_prepare_cpus(unsigned int max_cpus) +void __init platform_smp_prepare_cpus(unsigned int max_cpus) { - unsigned int ncores = num_possible_cpus(); - unsigned int cpu = smp_processor_id(); - int i; - - smp_store_cpu_info(cpu); - - /* are we trying to boot more cores than exist? */ - if (max_cpus > ncores) - max_cpus = ncores; + smp_init_cpu_present(max_cpus); /* - * Initialise the present map, which describes the set of CPUs - * actually populated at the present time. + * Write the address of secondary startup into the + * system-wide flags register. The boot monitor waits + * until it receives a soft interrupt, and then the + * secondary CPU branches to this address. */ - for (i = 0; i < max_cpus; i++) - set_cpu_present(i, true); - - /* - * Initialise the SCU if there are more than one CPU and let - * them know where to start. - */ - if (max_cpus > 1) { - /* - * Enable the local timer or broadcast device for the - * boot CPU, but only if we have more than one CPU. - */ - percpu_timer_setup(); - - scu_enable(scu_base_addr()); - - /* - * Write the address of secondary startup into the - * system-wide flags register. The boot monitor waits - * until it receives a soft interrupt, and then the - * secondary CPU branches to this address. - */ __raw_writel(BSYM(virt_to_phys(s5pv310_secondary_startup)), S5P_VA_SYSRAM); - } } diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c index 1c0fd92..abbb97b 100644 --- a/arch/arm/mach-tegra/platsmp.c +++ b/arch/arm/mach-tegra/platsmp.c @@ -22,7 +22,6 @@ #include <asm/cacheflush.h> #include <mach/hardware.h> #include <asm/mach-types.h> -#include <asm/localtimer.h> #include <asm/smp_scu.h> #include <mach/iomap.h> @@ -115,42 +114,10 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) */ void __init smp_init_cpus(void) { - unsigned int i, ncores = scu_get_core_count(scu_base); - - for (i = 0; i < ncores; i++) - cpu_set(i, cpu_possible_map); + smp_init_cpu_possible(scu_get_core_count(scu_base)); } -void __init smp_prepare_cpus(unsigned int max_cpus) +void __init platform_smp_prepare_cpus(unsigned int max_cpus) { - unsigned int ncores = scu_get_core_count(scu_base); - unsigned int cpu = smp_processor_id(); - int i; - - smp_store_cpu_info(cpu); - - /* - * are we trying to boot more cores than exist? - */ - if (max_cpus > ncores) - max_cpus = ncores; - - /* - * Initialise the present map, which describes the set of CPUs - * actually populated at the present time. - */ - for (i = 0; i < max_cpus; i++) - set_cpu_present(i, true); - - /* - * Initialise the SCU if there are more than one CPU and let - * them know where to start. Note that, on modern versions of - * MILO, the "poke" doesn't actually do anything until each - * individual core is sent a soft interrupt to get it out of - * WFI - */ - if (max_cpus > 1) { - percpu_timer_setup(); - scu_enable(scu_base); - } + smp_init_cpu_present(max_cpus); } diff --git a/arch/arm/mach-ux500/platsmp.c b/arch/arm/mach-ux500/platsmp.c index b8987bd..e03a5d0 100644 --- a/arch/arm/mach-ux500/platsmp.c +++ b/arch/arm/mach-ux500/platsmp.c @@ -18,7 +18,6 @@ #include <linux/io.h> #include <asm/cacheflush.h> -#include <asm/localtimer.h> #include <asm/smp_scu.h> #include <mach/hardware.h> @@ -28,11 +27,6 @@ */ volatile int __cpuinitdata pen_release = -1; -static unsigned int __init get_core_count(void) -{ - return scu_get_core_count(__io_address(UX500_SCU_BASE)); -} - static DEFINE_SPINLOCK(boot_lock); void __cpuinit platform_secondary_init(unsigned int cpu) @@ -126,55 +120,18 @@ static void __init wakeup_secondary(void) */ void __init smp_init_cpus(void) { - unsigned int i, ncores = get_core_count(); + unsigned int ncores = scu_get_core_count(__io_address(UX500_SCU_BASE)); - for (i = 0; i < ncores; i++) - set_cpu_possible(i, true); + smp_init_cpu_possible(ncores); } void __init smp_prepare_cpus(unsigned int max_cpus) { - unsigned int ncores = get_core_count(); - unsigned int cpu = smp_processor_id(); - int i; - - /* sanity check */ - if (ncores == 0) { - printk(KERN_ERR - "U8500: strange CM count of 0? Default to 1\n"); - ncores = 1; - } - - if (ncores > num_possible_cpus()) { - printk(KERN_WARNING - "U8500: no. of cores (%d) greater than configured " - "maximum of %d - clipping\n", - ncores, num_possible_cpus()); - ncores = num_possible_cpus(); - } - - smp_store_cpu_info(cpu); + smp_init_cpu_present(max_cpus); /* - * are we trying to boot more cores than exist? + * Enable the local timer or broadcast device for the + * boot CPU, but only if we have more than one CPU. */ - if (max_cpus > ncores) - max_cpus = ncores; - - /* - * Initialise the present map, which describes the set of CPUs - * actually populated at the present time. - */ - for (i = 0; i < max_cpus; i++) - set_cpu_present(i, true); - - if (max_cpus > 1) { - /* - * Enable the local timer or broadcast device for the - * boot CPU, but only if we have more than one CPU. - */ - percpu_timer_setup(); - scu_enable(__io_address(UX500_SCU_BASE)); - wakeup_secondary(); - } + wakeup_secondary(); } diff --git a/arch/arm/mach-vexpress/platsmp.c b/arch/arm/mach-vexpress/platsmp.c index 276f916..92ef7cb 100644 --- a/arch/arm/mach-vexpress/platsmp.c +++ b/arch/arm/mach-vexpress/platsmp.c @@ -17,7 +17,6 @@ #include <linux/io.h> #include <asm/cacheflush.h> -#include <asm/localtimer.h> #include <asm/smp_scu.h> #include <asm/unified.h> @@ -119,72 +118,24 @@ int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) void __init smp_init_cpus(void) { void __iomem *scu_base = scu_base_addr(); - unsigned int i, ncores; + unsigned int ncores; ncores = scu_base ? scu_get_core_count(scu_base) : 1; - /* sanity check */ - if (ncores == 0) { - printk(KERN_ERR - "vexpress: strange CM count of 0? Default to 1\n"); - - ncores = 1; - } - - if (ncores > NR_CPUS) { - printk(KERN_WARNING - "vexpress: no. of cores (%d) greater than configured " - "maximum of %d - clipping\n", - ncores, NR_CPUS); - ncores = NR_CPUS; - } - - for (i = 0; i < ncores; i++) - set_cpu_possible(i, true); + smp_init_cpu_possible(ncores); } void __init smp_prepare_cpus(unsigned int max_cpus) { - unsigned int ncores = num_possible_cpus(); - unsigned int cpu = smp_processor_id(); - int i; - - smp_store_cpu_info(cpu); + smp_init_cpu_present(max_cpus); /* - * are we trying to boot more cores than exist? + * Write the address of secondary startup into the + * system-wide flags register. The boot monitor waits + * until it receives a soft interrupt, and then the + * secondary CPU branches to this address. */ - if (max_cpus > ncores) - max_cpus = ncores; - - /* - * Initialise the present map, which describes the set of CPUs - * actually populated at the present time. - */ - for (i = 0; i < max_cpus; i++) - set_cpu_present(i, true); - - /* - * Initialise the SCU if there are more than one CPU and let - * them know where to start. - */ - if (max_cpus > 1) { - /* - * Enable the local timer or broadcast device for the - * boot CPU, but only if we have more than one CPU. - */ - percpu_timer_setup(); - - scu_enable(scu_base_addr()); - - /* - * Write the address of secondary startup into the - * system-wide flags register. The boot monitor waits - * until it receives a soft interrupt, and then the - * secondary CPU branches to this address. - */ - writel(~0, MMIO_P2V(V2M_SYS_FLAGSCLR)); - writel(BSYM(virt_to_phys(vexpress_secondary_startup)), - MMIO_P2V(V2M_SYS_FLAGSSET)); - } + writel(~0, MMIO_P2V(V2M_SYS_FLAGSCLR)); + writel(BSYM(virt_to_phys(vexpress_secondary_startup)), + MMIO_P2V(V2M_SYS_FLAGSSET)); } -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html