diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm/Kconfig | 5 | ||||
| -rw-r--r-- | arch/arm/mach-vexpress/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm/mach-vexpress/headsmp.S | 39 | ||||
| -rw-r--r-- | arch/arm/mach-vexpress/include/mach/smp.h | 21 | ||||
| -rw-r--r-- | arch/arm/mach-vexpress/localtimer.c | 26 | ||||
| -rw-r--r-- | arch/arm/mach-vexpress/platsmp.c | 190 |
6 files changed, 281 insertions, 2 deletions
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 58080e17c28b..4bb7730a2682 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1121,10 +1121,11 @@ source "kernel/time/Kconfig" config SMP bool "Symmetric Multi-Processing (EXPERIMENTAL)" depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\ - MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500) + MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 ||\ + ARCH_U8500 || ARCH_VEXPRESS_CA9X4) depends on GENERIC_CLOCKEVENTS select USE_GENERIC_SMP_HELPERS - select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500) + select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500 || ARCH_VEXPRESS_CA9X4) help This enables support for systems with more than one CPU. If you have a system with only one CPU, like most personal computers, say N. If diff --git a/arch/arm/mach-vexpress/Makefile b/arch/arm/mach-vexpress/Makefile index 3c5e1609fc4f..1b71b77ade22 100644 --- a/arch/arm/mach-vexpress/Makefile +++ b/arch/arm/mach-vexpress/Makefile @@ -4,3 +4,5 @@ obj-y := v2m.o obj-$(CONFIG_ARCH_VEXPRESS_CA9X4) += ct-ca9x4.o +obj-$(CONFIG_SMP) += platsmp.o headsmp.o +obj-$(CONFIG_LOCAL_TIMERS) += localtimer.o diff --git a/arch/arm/mach-vexpress/headsmp.S b/arch/arm/mach-vexpress/headsmp.S new file mode 100644 index 000000000000..8a78ff68e1ee --- /dev/null +++ b/arch/arm/mach-vexpress/headsmp.S @@ -0,0 +1,39 @@ +/* + * linux/arch/arm/mach-vexpress/headsmp.S + * + * 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 + +/* + * Versatile Express specific entry point for secondary CPUs. This + * provides a "holding pen" into which all secondary cores are held + * until we're ready for them to initialise. + */ +ENTRY(vexpress_secondary_startup) + mrc p15, 0, r0, c0, c0, 5 + and r0, r0, #15 + adr r4, 1f + ldmia r4, {r5, r6} + sub r4, r4, r5 + add r6, r6, r4 +pen: ldr r7, [r6] + cmp r7, r0 + bne pen + + /* + * we've been released from the holding pen: secondary_stack + * should now contain the SVC stack for this core + */ + b secondary_startup + +1: .long . + .long pen_release diff --git a/arch/arm/mach-vexpress/include/mach/smp.h b/arch/arm/mach-vexpress/include/mach/smp.h new file mode 100644 index 000000000000..72a9621ed087 --- /dev/null +++ b/arch/arm/mach-vexpress/include/mach/smp.h @@ -0,0 +1,21 @@ +#ifndef __MACH_SMP_H +#define __MACH_SMP_H + +#include <asm/hardware/gic.h> + +#define hard_smp_processor_id() \ + ({ \ + unsigned int cpunum; \ + __asm__("mrc p15, 0, %0, c0, c0, 5" \ + : "=r" (cpunum)); \ + cpunum &= 0x0F; \ + }) + +/* + * We use IRQ1 as the IPI + */ +static inline void smp_cross_call(const struct cpumask *mask) +{ + gic_raise_softirq(mask, 1); +} +#endif diff --git a/arch/arm/mach-vexpress/localtimer.c b/arch/arm/mach-vexpress/localtimer.c new file mode 100644 index 000000000000..c0e3a59a0bfc --- /dev/null +++ b/arch/arm/mach-vexpress/localtimer.c @@ -0,0 +1,26 @@ +/* + * linux/arch/arm/mach-vexpress/localtimer.c + * + * 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> +#include <mach/irqs.h> + +/* + * Setup the local clock events for a CPU. + */ +void __cpuinit local_timer_setup(struct clock_event_device *evt) +{ + evt->irq = IRQ_LOCALTIMER; + twd_timer_setup(evt); +} diff --git a/arch/arm/mach-vexpress/platsmp.c b/arch/arm/mach-vexpress/platsmp.c new file mode 100644 index 000000000000..670970699ba9 --- /dev/null +++ b/arch/arm/mach-vexpress/platsmp.c @@ -0,0 +1,190 @@ +/* + * linux/arch/arm/mach-vexpress/platsmp.c + * + * 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/jiffies.h> +#include <linux/smp.h> +#include <linux/io.h> + +#include <asm/cacheflush.h> +#include <asm/localtimer.h> +#include <asm/smp_scu.h> +#include <asm/unified.h> + +#include <mach/ct-ca9x4.h> +#include <mach/motherboard.h> +#define V2M_PA_CS7 0x10000000 + +#include "core.h" + +extern void vexpress_secondary_startup(void); + +/* + * control for which core is the next to come out of the secondary + * boot "holding pen" + */ +volatile int __cpuinitdata pen_release = -1; + +static void __iomem *scu_base_addr(void) +{ + return MMIO_P2V(A9_MPCORE_SCU); +} + +static DEFINE_SPINLOCK(boot_lock); + +void __cpuinit platform_secondary_init(unsigned int cpu) +{ + trace_hardirqs_off(); + + /* + * if any interrupts are already enabled for the primary + * core (e.g. timer irq), then they will not have been enabled + * for us: do so + */ + gic_cpu_init(0, gic_cpu_base_addr); + + /* + * let the primary processor know we're out of the + * pen, then head off into the C entry point + */ + pen_release = -1; + smp_wmb(); + + /* + * Synchronise with the boot thread. + */ + spin_lock(&boot_lock); + spin_unlock(&boot_lock); +} + +int __cpuinit boot_secondary(unsigned int cpu, struct task_struct *idle) +{ + unsigned long timeout; + + /* + * Set synchronisation state between this boot processor + * and the secondary one + */ + spin_lock(&boot_lock); + + /* + * This is really belt and braces; we hold unintended secondary + * CPUs in the holding pen until we're ready for them. However, + * since we haven't sent them a soft interrupt, they shouldn't + * be there. + */ + pen_release = cpu; + __cpuc_flush_dcache_area((void *)&pen_release, sizeof(pen_release)); + outer_clean_range(__pa(&pen_release), __pa(&pen_release + 1)); + + /* + * Send the secondary CPU a soft interrupt, thereby causing + * the boot monitor to read the system wide flags register, + * and branch to the address found there. + */ + smp_cross_call(cpumask_of(cpu)); + + timeout = jiffies + (1 * HZ); + while (time_before(jiffies, timeout)) { + smp_rmb(); + if (pen_release == -1) + break; + + udelay(10); + } + + /* + * now the secondary core is starting up let it run its + * calibrations, then wait for it to finish + */ + spin_unlock(&boot_lock); + + return pen_release != -1 ? -ENOSYS : 0; +} + +/* + * Initialise the CPU possible map early - this describes the CPUs + * which may be present or become present in the system. + */ +void __init smp_init_cpus(void) +{ + void __iomem *scu_base = scu_base_addr(); + unsigned int i, 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); +} + +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); + + /* + * 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. + */ + 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)); + } +} |