LXR linux/arch/blackfin/mach-bf561/smp.c

   1/*
   2 * Copyright 2007-2009 Analog Devices Inc.
   3 *               Philippe Gerum <rpm@xenomai.org>
   4 *
   5 * Licensed under the GPL-2 or later.
   6 */
   7
   8#include <linux/init.h>
   9#include <linux/kernel.h>
  10#include <linux/sched.h>
  11#include <linux/delay.h>
  12#include <asm/smp.h>
  13#include <asm/dma.h>
  14#include <asm/time.h>
  15
  16static DEFINE_SPINLOCK(boot_lock);
  17
  18/*
  19 * platform_init_cpus() - Tell the world about how many cores we
  20 * have. This is called while setting up the architecture support
  21 * (setup_arch()), so don't be too demanding here with respect to
  22 * available kernel services.
  23 */
  24
  25void __init platform_init_cpus(void)
  26{
  27        struct cpumask mask;
  28
  29        cpumask_set_cpu(0, &mask); /* CoreA */
  30        cpumask_set_cpu(1, &mask); /* CoreB */
  31        init_cpu_possible(&mask);
  32}
  33
  34void __init platform_prepare_cpus(unsigned int max_cpus)
  35{
  36        struct cpumask mask;
  37
  38        bfin_relocate_coreb_l1_mem();
  39
  40        /* Both cores ought to be present on a bf561! */
  41        cpumask_set_cpu(0, &mask); /* CoreA */
  42        cpumask_set_cpu(1, &mask); /* CoreB */
  43        init_cpu_present(&mask);
  44}
  45
  46int __init setup_profiling_timer(unsigned int multiplier) /* not supported */
  47{
  48        return -EINVAL;
  49}
  50
  51void __cpuinit platform_secondary_init(unsigned int cpu)
  52{
  53        /* Clone setup for peripheral interrupt sources from CoreA. */
  54        bfin_write_SICB_IMASK0(bfin_read_SIC_IMASK0());
  55        bfin_write_SICB_IMASK1(bfin_read_SIC_IMASK1());
  56        SSYNC();
  57
  58        /* Clone setup for IARs from CoreA. */
  59        bfin_write_SICB_IAR0(bfin_read_SIC_IAR0());
  60        bfin_write_SICB_IAR1(bfin_read_SIC_IAR1());
  61        bfin_write_SICB_IAR2(bfin_read_SIC_IAR2());
  62        bfin_write_SICB_IAR3(bfin_read_SIC_IAR3());
  63        bfin_write_SICB_IAR4(bfin_read_SIC_IAR4());
  64        bfin_write_SICB_IAR5(bfin_read_SIC_IAR5());
  65        bfin_write_SICB_IAR6(bfin_read_SIC_IAR6());
  66        bfin_write_SICB_IAR7(bfin_read_SIC_IAR7());
  67        bfin_write_SICB_IWR0(IWR_DISABLE_ALL);
  68        bfin_write_SICB_IWR1(IWR_DISABLE_ALL);
  69        SSYNC();
  70
  71        /* We are done with local CPU inits, unblock the boot CPU. */
  72        set_cpu_online(cpu, true);
  73        spin_lock(&boot_lock);
  74        spin_unlock(&boot_lock);
  75}
  76
  77int __cpuinit platform_boot_secondary(unsigned int cpu, struct task_struct *idle)
  78{
  79        unsigned long timeout;
  80
  81        printk(KERN_INFO "Booting Core B.\n");
  82
  83        spin_lock(&boot_lock);
  84
  85        if ((bfin_read_SYSCR() & COREB_SRAM_INIT) == 0) {
  86                /* CoreB already running, sending ipi to wakeup it */
  87                smp_send_reschedule(cpu);
  88        } else {
  89                /* Kick CoreB, which should start execution from CORE_SRAM_BASE. */
  90                bfin_write_SYSCR(bfin_read_SYSCR() & ~COREB_SRAM_INIT);
  91                SSYNC();
  92        }
  93
  94        timeout = jiffies + 1 * HZ;
  95        while (time_before(jiffies, timeout)) {
  96                if (cpu_online(cpu))
  97                        break;
  98                udelay(100);
  99                barrier();
 100        }
 101
 102        if (cpu_online(cpu)) {
 103                /* release the lock and let coreb run */
 104                spin_unlock(&boot_lock);
 105                return 0;
 106        } else
 107                panic("CPU%u: processor failed to boot\n", cpu);
 108}
 109
 110static const char supple0[] = "IRQ_SUPPLE_0";
 111static const char supple1[] = "IRQ_SUPPLE_1";
 112void __init platform_request_ipi(int irq, void *handler)
 113{
 114        int ret;
 115        const char *name = (irq == IRQ_SUPPLE_0) ? supple0 : supple1;
 116
 117        ret = request_irq(irq, handler, IRQF_PERCPU | IRQF_NO_SUSPEND |
 118                        IRQF_FORCE_RESUME, name, handler);
 119        if (ret)
 120                panic("Cannot request %s for IPI service", name);
 121}
 122
 123void platform_send_ipi(cpumask_t callmap, int irq)
 124{
 125        unsigned int cpu;
 126        int offset = (irq == IRQ_SUPPLE_0) ? 6 : 8;
 127
 128        for_each_cpu_mask(cpu, callmap) {
 129                BUG_ON(cpu >= 2);
 130                SSYNC();
 131                bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (offset + cpu)));
 132                SSYNC();
 133        }
 134}
 135
 136void platform_send_ipi_cpu(unsigned int cpu, int irq)
 137{
 138        int offset = (irq == IRQ_SUPPLE_0) ? 6 : 8;
 139        BUG_ON(cpu >= 2);
 140        SSYNC();
 141        bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (offset + cpu)));
 142        SSYNC();
 143}
 144
 145void platform_clear_ipi(unsigned int cpu, int irq)
 146{
 147        int offset = (irq == IRQ_SUPPLE_0) ? 10 : 12;
 148        BUG_ON(cpu >= 2);
 149        SSYNC();
 150        bfin_write_SICB_SYSCR(bfin_read_SICB_SYSCR() | (1 << (offset + cpu)));
 151        SSYNC();
 152}
 153
 154/*
 155 * Setup core B's local core timer.
 156 * In SMP, core timer is used for clock event device.
 157 */
 158void __cpuinit bfin_local_timer_setup(void)
 159{
 160#if defined(CONFIG_TICKSOURCE_CORETMR)
 161        struct irq_data *data = irq_get_irq_data(IRQ_CORETMR);
 162        struct irq_chip *chip = irq_data_get_irq_chip(data);
 163
 164        bfin_coretmr_init();
 165        bfin_coretmr_clockevent_init();
 166
 167        chip->irq_unmask(data);
 168#else
 169        /* Power down the core timer, just to play safe. */
 170        bfin_write_TCNTL(0);
 171#endif
 172
 173}
 174