diff options
Diffstat (limited to 'arch/x86_64/kernel/smpboot.c')
| -rw-r--r-- | arch/x86_64/kernel/smpboot.c | 938 |
1 files changed, 938 insertions, 0 deletions
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c new file mode 100644 index 00000000000..afd3600b919 --- /dev/null +++ b/arch/x86_64/kernel/smpboot.c @@ -0,0 +1,938 @@ +/* + * x86 SMP booting functions + * + * (c) 1995 Alan Cox, Building #3 <alan@redhat.com> + * (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com> + * Copyright 2001 Andi Kleen, SuSE Labs. + * + * Much of the core SMP work is based on previous work by Thomas Radke, to + * whom a great many thanks are extended. + * + * Thanks to Intel for making available several different Pentium, + * Pentium Pro and Pentium-II/Xeon MP machines. + * Original development of Linux SMP code supported by Caldera. + * + * This code is released under the GNU General Public License version 2 or + * later. + * + * Fixes + * Felix Koop : NR_CPUS used properly + * Jose Renau : Handle single CPU case. + * Alan Cox : By repeated request 8) - Total BogoMIP report. + * Greg Wright : Fix for kernel stacks panic. + * Erich Boleyn : MP v1.4 and additional changes. + * Matthias Sattler : Changes for 2.1 kernel map. + * Michel Lespinasse : Changes for 2.1 kernel map. + * Michael Chastain : Change trampoline.S to gnu as. + * Alan Cox : Dumb bug: 'B' step PPro's are fine + * Ingo Molnar : Added APIC timers, based on code + * from Jose Renau + * Ingo Molnar : various cleanups and rewrites + * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug. + * Maciej W. Rozycki : Bits for genuine 82489DX APICs + * Andi Kleen : Changed for SMP boot into long mode. + * Rusty Russell : Hacked into shape for new "hotplug" boot process. + */ + +#include <linux/config.h> +#include <linux/init.h> + +#include <linux/mm.h> +#include <linux/kernel_stat.h> +#include <linux/smp_lock.h> +#include <linux/irq.h> +#include <linux/bootmem.h> +#include <linux/thread_info.h> +#include <linux/module.h> + +#include <linux/delay.h> +#include <linux/mc146818rtc.h> +#include <asm/mtrr.h> +#include <asm/pgalloc.h> +#include <asm/desc.h> +#include <asm/kdebug.h> +#include <asm/tlbflush.h> +#include <asm/proto.h> + +/* Number of siblings per CPU package */ +int smp_num_siblings = 1; +/* Package ID of each logical CPU */ +u8 phys_proc_id[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID }; +EXPORT_SYMBOL(phys_proc_id); + +/* Bitmask of currently online CPUs */ +cpumask_t cpu_online_map; + +cpumask_t cpu_callin_map; +cpumask_t cpu_callout_map; +static cpumask_t smp_commenced_mask; + +/* Per CPU bogomips and other parameters */ +struct cpuinfo_x86 cpu_data[NR_CPUS] __cacheline_aligned; + +cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned; + +/* + * Trampoline 80x86 program as an array. + */ + +extern unsigned char trampoline_data []; +extern unsigned char trampoline_end []; + +/* + * Currently trivial. Write the real->protected mode + * bootstrap into the page concerned. The caller + * has made sure it's suitably aligned. + */ + +static unsigned long __init setup_trampoline(void) +{ + void *tramp = __va(SMP_TRAMPOLINE_BASE); + memcpy(tramp, trampoline_data, trampoline_end - trampoline_data); + return virt_to_phys(tramp); +} + +/* + * The bootstrap kernel entry code has set these up. Save them for + * a given CPU + */ + +static void __init smp_store_cpu_info(int id) +{ + struct cpuinfo_x86 *c = cpu_data + id; + + *c = boot_cpu_data; + identify_cpu(c); +} + +/* + * TSC synchronization. + * + * We first check whether all CPUs have their TSC's synchronized, + * then we print a warning if not, and always resync. + */ + +static atomic_t tsc_start_flag = ATOMIC_INIT(0); +static atomic_t tsc_count_start = ATOMIC_INIT(0); +static atomic_t tsc_count_stop = ATOMIC_INIT(0); +static unsigned long long tsc_values[NR_CPUS]; + +#define NR_LOOPS 5 + +extern unsigned int fast_gettimeoffset_quotient; + +static void __init synchronize_tsc_bp (void) +{ + int i; + unsigned long long t0; + unsigned long long sum, avg; + long long delta; + long one_usec; + int buggy = 0; + + printk(KERN_INFO "checking TSC synchronization across %u CPUs: ",num_booting_cpus()); + + one_usec = cpu_khz; + + atomic_set(&tsc_start_flag, 1); + wmb(); + + /* + * We loop a few times to get a primed instruction cache, + * then the last pass is more or less synchronized and + * the BP and APs set their cycle counters to zero all at + * once. This reduces the chance of having random offsets + * between the processors, and guarantees that the maximum + * delay between the cycle counters is never bigger than + * the latency of information-passing (cachelines) between + * two CPUs. + */ + for (i = 0; i < NR_LOOPS; i++) { + /* + * all APs synchronize but they loop on '== num_cpus' + */ + while (atomic_read(&tsc_count_start) != num_booting_cpus()-1) mb(); + atomic_set(&tsc_count_stop, 0); + wmb(); + /* + * this lets the APs save their current TSC: + */ + atomic_inc(&tsc_count_start); + + sync_core(); + rdtscll(tsc_values[smp_processor_id()]); + /* + * We clear the TSC in the last loop: + */ + if (i == NR_LOOPS-1) + write_tsc(0, 0); + + /* + * Wait for all APs to leave the synchronization point: + */ + while (atomic_read(&tsc_count_stop) != num_booting_cpus()-1) mb(); + atomic_set(&tsc_count_start, 0); + wmb(); + atomic_inc(&tsc_count_stop); + } + + sum = 0; + for (i = 0; i < NR_CPUS; i++) { + if (cpu_isset(i, cpu_callout_map)) { + t0 = tsc_values[i]; + sum += t0; + } + } + avg = sum / num_booting_cpus(); + + sum = 0; + for (i = 0; i < NR_CPUS; i++) { + if (!cpu_isset(i, cpu_callout_map)) + continue; + + delta = tsc_values[i] - avg; + if (delta < 0) + delta = -delta; + /* + * We report bigger than 2 microseconds clock differences. + */ + if (delta > 2*one_usec) { + long realdelta; + if (!buggy) { + buggy = 1; + printk("\n"); + } + realdelta = delta / one_usec; + if (tsc_values[i] < avg) + realdelta = -realdelta; + + printk("BIOS BUG: CPU#%d improperly initialized, has %ld usecs TSC skew! FIXED.\n", + i, realdelta); + } + + sum += delta; + } + if (!buggy) + printk("passed.\n"); +} + +static void __init synchronize_tsc_ap (void) +{ + int i; + + /* + * Not every cpu is online at the time + * this gets called, so we first wait for the BP to + * finish SMP initialization: + */ + while (!atomic_read(&tsc_start_flag)) mb(); + + for (i = 0; i < NR_LOOPS; i++) { + atomic_inc(&tsc_count_start); + while (atomic_read(&tsc_count_start) != num_booting_cpus()) mb(); + + sync_core(); + rdtscll(tsc_values[smp_processor_id()]); + if (i == NR_LOOPS-1) + write_tsc(0, 0); + + atomic_inc(&tsc_count_stop); + while (atomic_read(&tsc_count_stop) != num_booting_cpus()) mb(); + } +} +#undef NR_LOOPS + +static atomic_t init_deasserted; + +static void __init smp_callin(void) +{ + int cpuid, phys_id; + unsigned long timeout; + + /* + * If waken up by an INIT in an 82489DX configuration + * we may get here before an INIT-deassert IPI reaches + * our local APIC. We have to wait for the IPI or we'll + * lock up on an APIC access. + */ + while (!atomic_read(&init_deasserted)); + + /* + * (This works even if the APIC is not enabled.) + */ + phys_id = GET_APIC_ID(apic_read(APIC_ID)); + cpuid = smp_processor_id(); + if (cpu_isset(cpuid, cpu_callin_map)) { + panic("smp_callin: phys CPU#%d, CPU#%d already present??\n", + phys_id, cpuid); + } + Dprintk("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id); + + /* + * STARTUP IPIs are fragile beasts as they might sometimes + * trigger some glue motherboard logic. Complete APIC bus + * silence for 1 second, this overestimates the time the + * boot CPU is spending to send the up to 2 STARTUP IPIs + * by a factor of two. This should be enough. + */ + + /* + * Waiting 2s total for startup (udelay is not yet working) + */ + timeout = jiffies + 2*HZ; + while (time_before(jiffies, timeout)) { + /* + * Has the boot CPU finished it's STARTUP sequence? + */ + if (cpu_isset(cpuid, cpu_callout_map)) + break; + rep_nop(); + } + + if (!time_before(jiffies, timeout)) { + panic("smp_callin: CPU%d started up but did not get a callout!\n", + cpuid); + } + + /* + * the boot CPU has finished the init stage and is spinning + * on callin_map until we finish. We are free to set up this + * CPU, first the APIC. (this is probably redundant on most + * boards) + */ + + Dprintk("CALLIN, before setup_local_APIC().\n"); + setup_local_APIC(); + + local_irq_enable(); + + /* + * Get our bogomips. + */ + calibrate_delay(); + Dprintk("Stack at about %p\n",&cpuid); + + disable_APIC_timer(); + + /* + * Save our processor parameters + */ + smp_store_cpu_info(cpuid); + + local_irq_disable(); + + /* + * Allow the master to continue. + */ + cpu_set(cpuid, cpu_callin_map); + + /* + * Synchronize the TSC with the BP + */ + if (cpu_has_tsc) + synchronize_tsc_ap(); +} + +static int cpucount; + +/* + * Activate a secondary processor. + */ +void __init start_secondary(void) +{ + /* + * Dont put anything before smp_callin(), SMP + * booting is too fragile that we want to limit the + * things done here to the most necessary things. + */ + cpu_init(); + smp_callin(); + + /* otherwise gcc will move up the smp_processor_id before the cpu_init */ + barrier(); + + Dprintk("cpu %d: waiting for commence\n", smp_processor_id()); + while (!cpu_isset(smp_processor_id(), smp_commenced_mask)) + rep_nop(); + + Dprintk("cpu %d: setting up apic clock\n", smp_processor_id()); + setup_secondary_APIC_clock(); + + Dprintk("cpu %d: enabling apic timer\n", smp_processor_id()); + + if (nmi_watchdog == NMI_IO_APIC) { + disable_8259A_irq(0); + enable_NMI_through_LVT0(NULL); + enable_8259A_irq(0); + } + + + enable_APIC_timer(); + + /* + * low-memory mappings have been cleared, flush them from + * the local TLBs too. + */ + local_flush_tlb(); + + Dprintk("cpu %d eSetting cpu_online_map\n", smp_processor_id()); + cpu_set(smp_processor_id(), cpu_online_map); + wmb(); + + cpu_idle(); +} + +extern volatile unsigned long init_rsp; +extern void (*initial_code)(void); + +#if APIC_DEBUG +static inline void inquire_remote_apic(int apicid) +{ + unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 }; + char *names[] = { "ID", "VERSION", "SPIV" }; + int timeout, status; + + printk(KERN_INFO "Inquiring remote APIC #%d...\n", apicid); + + for (i = 0; i < sizeof(regs) / sizeof(*regs); i++) { + printk("... APIC #%d %s: ", apicid, names[i]); + + /* + * Wait for idle. + */ + apic_wait_icr_idle(); + + apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(apicid)); + apic_write_around(APIC_ICR, APIC_DM_REMRD | regs[i]); + + timeout = 0; + do { + udelay(100); + status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK; + } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000); + + switch (status) { + case APIC_ICR_RR_VALID: + status = apic_read(APIC_RRR); + printk("%08x\n", status); + break; + default: + printk("failed\n"); + } + } +} +#endif + +static int __init wakeup_secondary_via_INIT(int phys_apicid, unsigned int start_rip) +{ + unsigned long send_status = 0, accept_status = 0; + int maxlvt, timeout, num_starts, j; + + Dprintk("Asserting INIT.\n"); + + /* + * Turn INIT on target chip + */ + apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid)); + + /* + * Send IPI + */ + apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_INT_ASSERT + | APIC_DM_INIT); + + Dprintk("Waiting for send to finish...\n"); + timeout = 0; + do { + Dprintk("+"); + udelay(100); + send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY; + } while (send_status && (timeout++ < 1000)); + + mdelay(10); + + Dprintk("Deasserting INIT.\n"); + + /* Target chip */ + apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid)); + + /* Send IPI */ + apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_DM_INIT); + + Dprintk("Waiting for send to finish...\n"); + timeout = 0; + do { + Dprintk("+"); + udelay(100); + send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY; + } while (send_status && (timeout++ < 1000)); + + atomic_set(&init_deasserted, 1); + + /* + * Should we send STARTUP IPIs ? + * + * Determine this based on the APIC version. + * If we don't have an integrated APIC, don't send the STARTUP IPIs. + */ + if (APIC_INTEGRATED(apic_version[phys_apicid])) + num_starts = 2; + else + num_starts = 0; + + /* + * Run STARTUP IPI loop. + */ + Dprintk("#startup loops: %d.\n", num_starts); + + maxlvt = get_maxlvt(); + + for (j = 1; j <= num_starts; j++) { + Dprintk("Sending STARTUP #%d.\n",j); + apic_read_around(APIC_SPIV); + apic_write(APIC_ESR, 0); + apic_read(APIC_ESR); + Dprintk("After apic_write.\n"); + + /* + * STARTUP IPI + */ + + /* Target chip */ + apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid)); + + /* Boot on the stack */ + /* Kick the second */ + apic_write_around(APIC_ICR, APIC_DM_STARTUP + | (start_rip >> 12)); + + /* + * Give the other CPU some time to accept the IPI. + */ + udelay(300); + + Dprintk("Startup point 1.\n"); + + Dprintk("Waiting for send to finish...\n"); + timeout = 0; + do { + Dprintk("+"); + udelay(100); + send_status = apic_read(APIC_ICR) & APIC_ICR_BUSY; + } while (send_status && (timeout++ < 1000)); + + /* + * Give the other CPU some time to accept the IPI. + */ + udelay(200); + /* + * Due to the Pentium erratum 3AP. + */ + if (maxlvt > 3) { + apic_read_around(APIC_SPIV); + apic_write(APIC_ESR, 0); + } + accept_status = (apic_read(APIC_ESR) & 0xEF); + if (send_status || accept_status) + break; + } + Dprintk("After Startup.\n"); + + if (send_status) + printk(KERN_ERR "APIC never delivered???\n"); + if (accept_status) + printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status); + + return (send_status | accept_status); +} + +static void __init do_boot_cpu (int apicid) +{ + struct task_struct *idle; + unsigned long boot_error; + int timeout, cpu; + unsigned long start_rip; + + cpu = ++cpucount; + /* + * We can't use kernel_thread since we must avoid to + * reschedule the child. + */ + idle = fork_idle(cpu); + if (IS_ERR(idle)) + panic("failed fork for CPU %d", cpu); + x86_cpu_to_apicid[cpu] = apicid; + + cpu_pda[cpu].pcurrent = idle; + + start_rip = setup_trampoline(); + + init_rsp = idle->thread.rsp; + per_cpu(init_tss,cpu).rsp0 = init_rsp; + initial_code = start_secondary; + clear_ti_thread_flag(idle->thread_info, TIF_FORK); + + printk(KERN_INFO "Booting processor %d/%d rip %lx rsp %lx\n", cpu, apicid, + start_rip, init_rsp); + + /* + * This grunge runs the startup process for + * the targeted processor. + */ + + atomic_set(&init_deasserted, 0); + + Dprintk("Setting warm reset code and vector.\n"); + + CMOS_WRITE(0xa, 0xf); + local_flush_tlb(); + Dprintk("1.\n"); + *((volatile unsigned short *) phys_to_virt(0x469)) = start_rip >> 4; + Dprintk("2.\n"); + *((volatile unsigned short *) phys_to_virt(0x467)) = start_rip & 0xf; + Dprintk("3.\n"); + + /* + * Be paranoid about clearing APIC errors. + */ + if (APIC_INTEGRATED(apic_version[apicid])) { + apic_read_around(APIC_SPIV); + apic_write(APIC_ESR, 0); + apic_read(APIC_ESR); + } + + /* + * Status is now clean + */ + boot_error = 0; + + /* + * Starting actual IPI sequence... + */ + boot_error = wakeup_secondary_via_INIT(apicid, start_rip); + + if (!boot_error) { + /* + * allow APs to start initializing. + */ + Dprintk("Before Callout %d.\n", cpu); + cpu_set(cpu, cpu_callout_map); + Dprintk("After Callout %d.\n", cpu); + + /* + * Wait 5s total for a response + */ + for (timeout = 0; timeout < 50000; timeout++) { + if (cpu_isset(cpu, cpu_callin_map)) + break; /* It has booted */ + udelay(100); + } + + if (cpu_isset(cpu, cpu_callin_map)) { + /* number CPUs logically, starting from 1 (BSP is 0) */ + Dprintk("OK.\n"); + print_cpu_info(&cpu_data[cpu]); + Dprintk("CPU has booted.\n"); + } else { + boot_error = 1; + if (*((volatile unsigned char *)phys_to_virt(SMP_TRAMPOLINE_BASE)) + == 0xA5) + /* trampoline started but...? */ + printk("Stuck ??\n"); + else + /* trampoline code not run */ + printk("Not responding.\n"); +#if APIC_DEBUG + inquire_remote_apic(apicid); +#endif + } + } + if (boot_error) { + cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */ + clear_bit(cpu, &cpu_initialized); /* was set by cpu_init() */ + cpucount--; + x86_cpu_to_apicid[cpu] = BAD_APICID; + x86_cpu_to_log_apicid[cpu] = BAD_APICID; + } +} + +static void smp_tune_scheduling (void) +{ + int cachesize; /* kB */ + unsigned long bandwidth = 1000; /* MB/s */ + /* + * Rough estimation for SMP scheduling, this is the number of + * cycles it takes for a fully memory-limited process to flush + * the SMP-local cache. + * + * (For a P5 this pretty much means we will choose another idle + * CPU almost always at wakeup time (this is due to the small + * L1 cache), on PIIs it's around 50-100 usecs, depending on + * the cache size) + */ + + if (!cpu_khz) { + return; + } else { + cachesize = boot_cpu_data.x86_cache_size; + if (cachesize == -1) { + cachesize = 16; /* Pentiums, 2x8kB cache */ + bandwidth = 100; + } + } +} + +/* + * Cycle through the processors sending APIC IPIs to boot each. + */ + +static void __init smp_boot_cpus(unsigned int max_cpus) +{ + unsigned apicid, cpu, bit, kicked; + + nmi_watchdog_default(); + + /* + * Setup boot CPU information + */ + smp_store_cpu_info(0); /* Final full version of the data */ + printk(KERN_INFO "CPU%d: ", 0); + print_cpu_info(&cpu_data[0]); + + current_thread_info()->cpu = 0; + smp_tune_scheduling(); + + if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) { + printk("weird, boot CPU (#%d) not listed by the BIOS.\n", + hard_smp_processor_id()); + physid_set(hard_smp_processor_id(), phys_cpu_present_map); + } + + /* + * If we couldn't find an SMP configuration at boot time, + * get out of here now! + */ + if (!smp_found_config) { + printk(KERN_NOTICE "SMP motherboard not detected.\n"); + io_apic_irqs = 0; + cpu_online_map = cpumask_of_cpu(0); + cpu_set(0, cpu_sibling_map[0]); + phys_cpu_present_map = physid_mask_of_physid(0); + if (APIC_init_uniprocessor()) + printk(KERN_NOTICE "Local APIC not detected." + " Using dummy APIC emulation.\n"); + goto smp_done; + } + + /* + * Should not be necessary because the MP table should list the boot + * CPU too, but we do it for the sake of robustness anyway. + */ + if (!physid_isset(boot_cpu_id, phys_cpu_present_map)) { + printk(KERN_NOTICE "weird, boot CPU (#%d) not listed by the BIOS.\n", + boot_cpu_id); + physid_set(hard_smp_processor_id(), phys_cpu_present_map); + } + + /* + * If we couldn't find a local APIC, then get out of here now! + */ + if (APIC_INTEGRATED(apic_version[boot_cpu_id]) && !cpu_has_apic) { + printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n", + boot_cpu_id); + printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n"); + io_apic_irqs = 0; + cpu_online_map = cpumask_of_cpu(0); + cpu_set(0, cpu_sibling_map[0]); + phys_cpu_present_map = physid_mask_of_physid(0); + disable_apic = 1; + goto smp_done; + } + + verify_local_APIC(); + + /* + * If SMP should be disabled, then really disable it! + */ + if (!max_cpus) { + smp_found_config = 0; + printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n"); + io_apic_irqs = 0; + cpu_online_map = cpumask_of_cpu(0); + cpu_set(0, cpu_sibling_map[0]); + phys_cpu_present_map = physid_mask_of_physid(0); + disable_apic = 1; + goto smp_done; + } + + connect_bsp_APIC(); + setup_local_APIC(); + + if (GET_APIC_ID(apic_read(APIC_ID)) != boot_cpu_id) + BUG(); + + x86_cpu_to_apicid[0] = boot_cpu_id; + + /* + * Now scan the CPU present map and fire up the other CPUs. + */ + Dprintk("CPU present map: %lx\n", physids_coerce(phys_cpu_present_map)); + + kicked = 1; + for (bit = 0; kicked < NR_CPUS && bit < MAX_APICS; bit++) { + apicid = cpu_present_to_apicid(bit); + /* + * Don't even attempt to start the boot CPU! + */ + if (apicid == boot_cpu_id || (apicid == BAD_APICID)) + continue; + + if (!physid_isset(apicid, phys_cpu_present_map)) + continue; + if ((max_cpus >= 0) && (max_cpus <= cpucount+1)) + continue; + + do_boot_cpu(apicid); + ++kicked; + } + + /* + * Cleanup possible dangling ends... + */ + { + /* + * Install writable page 0 entry to set BIOS data area. + */ + local_flush_tlb(); + + /* + * Paranoid: Set warm reset code and vector here back + * to default values. + */ + CMOS_WRITE(0, 0xf); + + *((volatile int *) phys_to_virt(0x467)) = 0; + } + + /* + * Allow the user to impress friends. + */ + + Dprintk("Before bogomips.\n"); + if (!cpucount) { + printk(KERN_INFO "Only one processor found.\n"); + } else { + unsigned long bogosum = 0; + for (cpu = 0; cpu < NR_CPUS; cpu++) + if (cpu_isset(cpu, cpu_callout_map)) + bogosum += cpu_data[cpu].loops_per_jiffy; + printk(KERN_INFO "Total of %d processors activated (%lu.%02lu BogoMIPS).\n", + cpucount+1, + bogosum/(500000/HZ), + (bogosum/(5000/HZ))%100); + Dprintk("Before bogocount - setting activated=1.\n"); + } + + /* + * Construct cpu_sibling_map[], so that we can tell the + * sibling CPU efficiently. + */ + for (cpu = 0; cpu < NR_CPUS; cpu++) + cpus_clear(cpu_sibling_map[cpu]); + + for (cpu = 0; cpu < NR_CPUS; cpu++) { + int siblings = 0; + int i; + if (!cpu_isset(cpu, cpu_callout_map)) + continue; + + if (smp_num_siblings > 1) { + for (i = 0; i < NR_CPUS; i++) { + if (!cpu_isset(i, cpu_callout_map)) + continue; + if (phys_proc_id[cpu] == phys_proc_id[i]) { + siblings++; + cpu_set(i, cpu_sibling_map[cpu]); + } + } + } else { + siblings++; + cpu_set(cpu, cpu_sibling_map[cpu]); + } + + if (siblings != smp_num_siblings) { + printk(KERN_WARNING + "WARNING: %d siblings found for CPU%d, should be %d\n", + siblings, cpu, smp_num_siblings); + smp_num_siblings = siblings; + } + } + + Dprintk("Boot done.\n"); + + /* + * Here we can be sure that there is an IO-APIC in the system. Let's + * go and set it up: + */ + if (!skip_ioapic_setup && nr_ioapics) + setup_IO_APIC(); + else + nr_ioapics = 0; + + setup_boot_APIC_clock(); + + /* + * Synchronize the TSC with the AP + */ + if (cpu_has_tsc && cpucount) + synchronize_tsc_bp(); + + smp_done: + time_init_smp(); +} + +/* These are wrappers to interface to the new boot process. Someone + who understands all this stuff should rewrite it properly. --RR 15/Jul/02 */ +void __init smp_prepare_cpus(unsigned int max_cpus) +{ + smp_boot_cpus(max_cpus); +} + +void __devinit smp_prepare_boot_cpu(void) +{ + cpu_set(smp_processor_id(), cpu_online_map); + cpu_set(smp_processor_id(), cpu_callout_map); +} + +int __devinit __cpu_up(unsigned int cpu) +{ + /* This only works at boot for x86. See "rewrite" above. */ + if (cpu_isset(cpu, smp_commenced_mask)) { + local_irq_enable(); + return -ENOSYS; + } + + /* In case one didn't come up */ + if (!cpu_isset(cpu, cpu_callin_map)) { + local_irq_enable(); + return -EIO; + } + local_irq_enable(); + + /* Unleash the CPU! */ + Dprintk("waiting for cpu %d\n", cpu); + + cpu_set(cpu, smp_commenced_mask); + while (!cpu_isset(cpu, cpu_online_map)) + mb(); + return 0; +} + +void __init smp_cpus_done(unsigned int max_cpus) +{ +#ifdef CONFIG_X86_IO_APIC + setup_ioapic_dest(); +#endif + zap_low_mappings(); +} + |