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Diffstat (limited to 'arch/i386/kernel/smpboot.c')
| -rw-r--r-- | arch/i386/kernel/smpboot.c | 1145 |
1 files changed, 1145 insertions, 0 deletions
diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c new file mode 100644 index 000000000000..332ee7a1d1a1 --- /dev/null +++ b/arch/i386/kernel/smpboot.c @@ -0,0 +1,1145 @@ +/* + * x86 SMP booting functions + * + * (c) 1995 Alan Cox, Building #3 <alan@redhat.com> + * (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com> + * + * 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 BogoMIPS 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 + * Martin J. Bligh : Added support for multi-quad systems + * Dave Jones : Report invalid combinations of Athlon CPUs. +* Rusty Russell : Hacked into shape for new "hotplug" boot process. */ + +#include <linux/module.h> +#include <linux/config.h> +#include <linux/init.h> +#include <linux/kernel.h> + +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/kernel_stat.h> +#include <linux/smp_lock.h> +#include <linux/irq.h> +#include <linux/bootmem.h> + +#include <linux/delay.h> +#include <linux/mc146818rtc.h> +#include <asm/tlbflush.h> +#include <asm/desc.h> +#include <asm/arch_hooks.h> + +#include <mach_apic.h> +#include <mach_wakecpu.h> +#include <smpboot_hooks.h> + +/* Set if we find a B stepping CPU */ +static int __initdata smp_b_stepping; + +/* Number of siblings per CPU package */ +int smp_num_siblings = 1; +int phys_proc_id[NR_CPUS]; /* Package ID of each logical CPU */ +EXPORT_SYMBOL(phys_proc_id); + +/* bitmap of 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; + +u8 x86_cpu_to_apicid[NR_CPUS] = + { [0 ... NR_CPUS-1] = 0xff }; +EXPORT_SYMBOL(x86_cpu_to_apicid); + +/* + * Trampoline 80x86 program as an array. + */ + +extern unsigned char trampoline_data []; +extern unsigned char trampoline_end []; +static unsigned char *trampoline_base; +static int trampoline_exec; + +static void map_cpu_to_logical_apicid(void); + +/* + * 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) +{ + memcpy(trampoline_base, trampoline_data, trampoline_end - trampoline_data); + return virt_to_phys(trampoline_base); +} + +/* + * We are called very early to get the low memory for the + * SMP bootup trampoline page. + */ +void __init smp_alloc_memory(void) +{ + trampoline_base = (void *) alloc_bootmem_low_pages(PAGE_SIZE); + /* + * Has to be in very low memory so we can execute + * real-mode AP code. + */ + if (__pa(trampoline_base) >= 0x9F000) + BUG(); + /* + * Make the SMP trampoline executable: + */ + trampoline_exec = set_kernel_exec((unsigned long)trampoline_base, 1); +} + +/* + * 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; + if (id!=0) + identify_cpu(c); + /* + * Mask B, Pentium, but not Pentium MMX + */ + if (c->x86_vendor == X86_VENDOR_INTEL && + c->x86 == 5 && + c->x86_mask >= 1 && c->x86_mask <= 4 && + c->x86_model <= 3) + /* + * Remember we have B step Pentia with bugs + */ + smp_b_stepping = 1; + + /* + * Certain Athlons might work (for various values of 'work') in SMP + * but they are not certified as MP capable. + */ + if ((c->x86_vendor == X86_VENDOR_AMD) && (c->x86 == 6)) { + + /* Athlon 660/661 is valid. */ + if ((c->x86_model==6) && ((c->x86_mask==0) || (c->x86_mask==1))) + goto valid_k7; + + /* Duron 670 is valid */ + if ((c->x86_model==7) && (c->x86_mask==0)) + goto valid_k7; + + /* + * Athlon 662, Duron 671, and Athlon >model 7 have capability bit. + * It's worth noting that the A5 stepping (662) of some Athlon XP's + * have the MP bit set. + * See http://www.heise.de/newsticker/data/jow-18.10.01-000 for more. + */ + if (((c->x86_model==6) && (c->x86_mask>=2)) || + ((c->x86_model==7) && (c->x86_mask>=1)) || + (c->x86_model> 7)) + if (cpu_has_mp) + goto valid_k7; + + /* If we get here, it's not a certified SMP capable AMD system. */ + tainted |= TAINT_UNSAFE_SMP; + } + +valid_k7: + ; +} + +/* + * 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 + +static void __init synchronize_tsc_bp (void) +{ + int i; + unsigned long long t0; + unsigned long long sum, avg; + long long delta; + unsigned long one_usec; + int buggy = 0; + + printk(KERN_INFO "checking TSC synchronization across %u CPUs: ", num_booting_cpus()); + + /* convert from kcyc/sec to cyc/usec */ + one_usec = cpu_khz / 1000; + + 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); + + 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; + do_div(avg, 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; + do_div(realdelta, one_usec); + if (tsc_values[i] < avg) + realdelta = -realdelta; + + printk(KERN_INFO "CPU#%d had %ld usecs TSC skew, fixed it up.\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(); + + 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 + +extern void calibrate_delay(void); + +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. + */ + wait_for_init_deassert(&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)) { + printk("huh, phys CPU#%d, CPU#%d already present??\n", + phys_id, cpuid); + BUG(); + } + 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)) { + printk("BUG: CPU%d started up but did not get a callout!\n", + cpuid); + BUG(); + } + + /* + * 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"); + smp_callin_clear_local_apic(); + setup_local_APIC(); + map_cpu_to_logical_apicid(); + + /* + * Get our bogomips. + */ + calibrate_delay(); + Dprintk("Stack at about %p\n",&cpuid); + + /* + * Save our processor parameters + */ + smp_store_cpu_info(cpuid); + + disable_APIC_timer(); + + /* + * Allow the master to continue. + */ + cpu_set(cpuid, cpu_callin_map); + + /* + * Synchronize the TSC with the BP + */ + if (cpu_has_tsc && cpu_khz) + synchronize_tsc_ap(); +} + +static int cpucount; + +/* + * Activate a secondary processor. + */ +static void __init start_secondary(void *unused) +{ + /* + * 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(); + while (!cpu_isset(smp_processor_id(), smp_commenced_mask)) + rep_nop(); + setup_secondary_APIC_clock(); + 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(); + cpu_set(smp_processor_id(), cpu_online_map); + + /* We can take interrupts now: we're officially "up". */ + local_irq_enable(); + + wmb(); + cpu_idle(); +} + +/* + * Everything has been set up for the secondary + * CPUs - they just need to reload everything + * from the task structure + * This function must not return. + */ +void __init initialize_secondary(void) +{ + /* + * We don't actually need to load the full TSS, + * basically just the stack pointer and the eip. + */ + + asm volatile( + "movl %0,%%esp\n\t" + "jmp *%1" + : + :"r" (current->thread.esp),"r" (current->thread.eip)); +} + +extern struct { + void * esp; + unsigned short ss; +} stack_start; + +#ifdef CONFIG_NUMA + +/* which logical CPUs are on which nodes */ +cpumask_t node_2_cpu_mask[MAX_NUMNODES] = + { [0 ... MAX_NUMNODES-1] = CPU_MASK_NONE }; +/* which node each logical CPU is on */ +int cpu_2_node[NR_CPUS] = { [0 ... NR_CPUS-1] = 0 }; +EXPORT_SYMBOL(cpu_2_node); + +/* set up a mapping between cpu and node. */ +static inline void map_cpu_to_node(int cpu, int node) +{ + printk("Mapping cpu %d to node %d\n", cpu, node); + cpu_set(cpu, node_2_cpu_mask[node]); + cpu_2_node[cpu] = node; +} + +/* undo a mapping between cpu and node. */ +static inline void unmap_cpu_to_node(int cpu) +{ + int node; + + printk("Unmapping cpu %d from all nodes\n", cpu); + for (node = 0; node < MAX_NUMNODES; node ++) + cpu_clear(cpu, node_2_cpu_mask[node]); + cpu_2_node[cpu] = 0; +} +#else /* !CONFIG_NUMA */ + +#define map_cpu_to_node(cpu, node) ({}) +#define unmap_cpu_to_node(cpu) ({}) + +#endif /* CONFIG_NUMA */ + +u8 cpu_2_logical_apicid[NR_CPUS] = { [0 ... NR_CPUS-1] = BAD_APICID }; + +static void map_cpu_to_logical_apicid(void) +{ + int cpu = smp_processor_id(); + int apicid = logical_smp_processor_id(); + + cpu_2_logical_apicid[cpu] = apicid; + map_cpu_to_node(cpu, apicid_to_node(apicid)); +} + +static void unmap_cpu_to_logical_apicid(int cpu) +{ + cpu_2_logical_apicid[cpu] = BAD_APICID; + unmap_cpu_to_node(cpu); +} + +#if APIC_DEBUG +static inline void __inquire_remote_apic(int apicid) +{ + int i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 }; + char *names[] = { "ID", "VERSION", "SPIV" }; + int timeout, status; + + printk("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 + +#ifdef WAKE_SECONDARY_VIA_NMI +/* + * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal + * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this + * won't ... remember to clear down the APIC, etc later. + */ +static int __init +wakeup_secondary_cpu(int logical_apicid, unsigned long start_eip) +{ + unsigned long send_status = 0, accept_status = 0; + int timeout, maxlvt; + + /* Target chip */ + apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(logical_apicid)); + + /* Boot on the stack */ + /* Kick the second */ + apic_write_around(APIC_ICR, APIC_DM_NMI | APIC_DEST_LOGICAL); + + 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. + */ + maxlvt = get_maxlvt(); + if (maxlvt > 3) { + apic_read_around(APIC_SPIV); + apic_write(APIC_ESR, 0); + } + accept_status = (apic_read(APIC_ESR) & 0xEF); + Dprintk("NMI sent.\n"); + + if (send_status) + printk("APIC never delivered???\n"); + if (accept_status) + printk("APIC delivery error (%lx).\n", accept_status); + + return (send_status | accept_status); +} +#endif /* WAKE_SECONDARY_VIA_NMI */ + +#ifdef WAKE_SECONDARY_VIA_INIT +static int __init +wakeup_secondary_cpu(int phys_apicid, unsigned long start_eip) +{ + unsigned long send_status = 0, accept_status = 0; + int maxlvt, timeout, num_starts, j; + + /* + * Be paranoid about clearing APIC errors. + */ + if (APIC_INTEGRATED(apic_version[phys_apicid])) { + apic_read_around(APIC_SPIV); + apic_write(APIC_ESR, 0); + apic_read(APIC_ESR); + } + + 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_eip >> 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("APIC never delivered???\n"); + if (accept_status) + printk("APIC delivery error (%lx).\n", accept_status); + + return (send_status | accept_status); +} +#endif /* WAKE_SECONDARY_VIA_INIT */ + +extern cpumask_t cpu_initialized; + +static int __init do_boot_cpu(int apicid) +/* + * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad + * (ie clustered apic addressing mode), this is a LOGICAL apic ID. + * Returns zero if CPU booted OK, else error code from wakeup_secondary_cpu. + */ +{ + struct task_struct *idle; + unsigned long boot_error; + int timeout, cpu; + unsigned long start_eip; + unsigned short nmi_high = 0, nmi_low = 0; + + 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); + idle->thread.eip = (unsigned long) start_secondary; + /* start_eip had better be page-aligned! */ + start_eip = setup_trampoline(); + + /* So we see what's up */ + printk("Booting processor %d/%d eip %lx\n", cpu, apicid, start_eip); + /* Stack for startup_32 can be just as for start_secondary onwards */ + stack_start.esp = (void *) idle->thread.esp; + + irq_ctx_init(cpu); + + /* + * This grunge runs the startup process for + * the targeted processor. + */ + + atomic_set(&init_deasserted, 0); + + Dprintk("Setting warm reset code and vector.\n"); + + store_NMI_vector(&nmi_high, &nmi_low); + + smpboot_setup_warm_reset_vector(start_eip); + + /* + * Starting actual IPI sequence... + */ + boot_error = wakeup_secondary_cpu(apicid, start_eip); + + 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"); + printk("CPU%d: ", cpu); + print_cpu_info(&cpu_data[cpu]); + Dprintk("CPU has booted.\n"); + } else { + boot_error= 1; + if (*((volatile unsigned char *)trampoline_base) + == 0xA5) + /* trampoline started but...? */ + printk("Stuck ??\n"); + else + /* trampoline code not run */ + printk("Not responding.\n"); + inquire_remote_apic(apicid); + } + } + x86_cpu_to_apicid[cpu] = apicid; + if (boot_error) { + /* Try to put things back the way they were before ... */ + unmap_cpu_to_logical_apicid(cpu); + cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */ + cpu_clear(cpu, cpu_initialized); /* was set by cpu_init() */ + cpucount--; + } + + /* mark "stuck" area as not stuck */ + *((volatile unsigned long *)trampoline_base) = 0; + + return boot_error; +} + +static void smp_tune_scheduling (void) +{ + unsigned long cachesize; /* kB */ + unsigned long bandwidth = 350; /* 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) { + /* + * this basically disables processor-affinity + * scheduling on SMP without a TSC. + */ + 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 int boot_cpu_logical_apicid; +/* Where the IO area was mapped on multiquad, always 0 otherwise */ +void *xquad_portio; + +cpumask_t cpu_sibling_map[NR_CPUS] __cacheline_aligned; + +static void __init smp_boot_cpus(unsigned int max_cpus) +{ + int apicid, cpu, bit, kicked; + unsigned long bogosum = 0; + + /* + * Setup boot CPU information + */ + smp_store_cpu_info(0); /* Final full version of the data */ + printk("CPU%d: ", 0); + print_cpu_info(&cpu_data[0]); + + boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID)); + boot_cpu_logical_apicid = logical_smp_processor_id(); + x86_cpu_to_apicid[0] = boot_cpu_physical_apicid; + + current_thread_info()->cpu = 0; + smp_tune_scheduling(); + cpus_clear(cpu_sibling_map[0]); + cpu_set(0, cpu_sibling_map[0]); + + /* + * If we couldn't find an SMP configuration at boot time, + * get out of here now! + */ + if (!smp_found_config && !acpi_lapic) { + printk(KERN_NOTICE "SMP motherboard not detected.\n"); + smpboot_clear_io_apic_irqs(); + 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"); + map_cpu_to_logical_apicid(); + return; + } + + /* + * Should not be necessary because the MP table should list the boot + * CPU too, but we do it for the sake of robustness anyway. + * Makes no sense to do this check in clustered apic mode, so skip it + */ + if (!check_phys_apicid_present(boot_cpu_physical_apicid)) { + printk("weird, boot CPU (#%d) not listed by the BIOS.\n", + boot_cpu_physical_apicid); + 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_physical_apicid]) && !cpu_has_apic) { + printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n", + boot_cpu_physical_apicid); + printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n"); + smpboot_clear_io_apic_irqs(); + phys_cpu_present_map = physid_mask_of_physid(0); + return; + } + + 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"); + smpboot_clear_io_apic_irqs(); + phys_cpu_present_map = physid_mask_of_physid(0); + return; + } + + connect_bsp_APIC(); + setup_local_APIC(); + map_cpu_to_logical_apicid(); + + + setup_portio_remap(); + + /* + * Scan the CPU present map and fire up the other CPUs via do_boot_cpu + * + * In clustered apic mode, phys_cpu_present_map is a constructed thus: + * bits 0-3 are quad0, 4-7 are quad1, etc. A perverse twist on the + * clustered apic ID. + */ + 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_apicid) || (apicid == BAD_APICID)) + continue; + + if (!check_apicid_present(bit)) + continue; + if (max_cpus <= cpucount+1) + continue; + + if (do_boot_cpu(apicid)) + printk("CPU #%d not responding - cannot use it.\n", + apicid); + else + ++kicked; + } + + /* + * Cleanup possible dangling ends... + */ + smpboot_restore_warm_reset_vector(); + + /* + * Allow the user to impress friends. + */ + Dprintk("Before bogomips.\n"); + 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"); + + if (smp_b_stepping) + printk(KERN_WARNING "WARNING: SMP operation may be unreliable with B stepping processors.\n"); + + /* + * Don't taint if we are running SMP kernel on a single non-MP + * approved Athlon + */ + if (tainted & TAINT_UNSAFE_SMP) { + if (cpucount) + printk (KERN_INFO "WARNING: This combination of AMD processors is not suitable for SMP.\n"); + else + tainted &= ~TAINT_UNSAFE_SMP; + } + + Dprintk("Boot done.\n"); + + /* + * construct cpu_sibling_map[], so that we can tell sibling CPUs + * 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); + } + + if (nmi_watchdog == NMI_LOCAL_APIC) + check_nmi_watchdog(); + + smpboot_setup_io_apic(); + + setup_boot_APIC_clock(); + + /* + * Synchronize the TSC with the AP + */ + if (cpu_has_tsc && cpucount && cpu_khz) + synchronize_tsc_bp(); +} + +/* 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! */ + 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(); + /* + * Disable executability of the SMP trampoline: + */ + set_kernel_exec((unsigned long)trampoline_base, trampoline_exec); +} + +void __init smp_intr_init(void) +{ + /* + * IRQ0 must be given a fixed assignment and initialized, + * because it's used before the IO-APIC is set up. + */ + set_intr_gate(FIRST_DEVICE_VECTOR, interrupt[0]); + + /* + * The reschedule interrupt is a CPU-to-CPU reschedule-helper + * IPI, driven by wakeup. + */ + set_intr_gate(RESCHEDULE_VECTOR, reschedule_interrupt); + + /* IPI for invalidation */ + set_intr_gate(INVALIDATE_TLB_VECTOR, invalidate_interrupt); + + /* IPI for generic function call */ + set_intr_gate(CALL_FUNCTION_VECTOR, call_function_interrupt); +} |