169a80d3fSPaul Mackerras /* 269a80d3fSPaul Mackerras * SMP support for pSeries machines. 369a80d3fSPaul Mackerras * 469a80d3fSPaul Mackerras * Dave Engebretsen, Peter Bergner, and 569a80d3fSPaul Mackerras * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com 669a80d3fSPaul Mackerras * 769a80d3fSPaul Mackerras * Plus various changes from other IBM teams... 869a80d3fSPaul Mackerras * 969a80d3fSPaul Mackerras * This program is free software; you can redistribute it and/or 1069a80d3fSPaul Mackerras * modify it under the terms of the GNU General Public License 1169a80d3fSPaul Mackerras * as published by the Free Software Foundation; either version 1269a80d3fSPaul Mackerras * 2 of the License, or (at your option) any later version. 1369a80d3fSPaul Mackerras */ 1469a80d3fSPaul Mackerras 1569a80d3fSPaul Mackerras 1669a80d3fSPaul Mackerras #include <linux/kernel.h> 1769a80d3fSPaul Mackerras #include <linux/module.h> 1869a80d3fSPaul Mackerras #include <linux/sched.h> 1969a80d3fSPaul Mackerras #include <linux/smp.h> 2069a80d3fSPaul Mackerras #include <linux/interrupt.h> 2169a80d3fSPaul Mackerras #include <linux/delay.h> 2269a80d3fSPaul Mackerras #include <linux/init.h> 2369a80d3fSPaul Mackerras #include <linux/spinlock.h> 2469a80d3fSPaul Mackerras #include <linux/cache.h> 2569a80d3fSPaul Mackerras #include <linux/err.h> 2669a80d3fSPaul Mackerras #include <linux/sysdev.h> 2769a80d3fSPaul Mackerras #include <linux/cpu.h> 2869a80d3fSPaul Mackerras 2969a80d3fSPaul Mackerras #include <asm/ptrace.h> 3069a80d3fSPaul Mackerras #include <asm/atomic.h> 3169a80d3fSPaul Mackerras #include <asm/irq.h> 3269a80d3fSPaul Mackerras #include <asm/page.h> 3369a80d3fSPaul Mackerras #include <asm/pgtable.h> 3469a80d3fSPaul Mackerras #include <asm/io.h> 3569a80d3fSPaul Mackerras #include <asm/prom.h> 3669a80d3fSPaul Mackerras #include <asm/smp.h> 3769a80d3fSPaul Mackerras #include <asm/paca.h> 3869a80d3fSPaul Mackerras #include <asm/machdep.h> 3969a80d3fSPaul Mackerras #include <asm/cputable.h> 4069a80d3fSPaul Mackerras #include <asm/firmware.h> 4169a80d3fSPaul Mackerras #include <asm/system.h> 4269a80d3fSPaul Mackerras #include <asm/rtas.h> 4369a80d3fSPaul Mackerras #include <asm/pSeries_reconfig.h> 4469a80d3fSPaul Mackerras #include <asm/mpic.h> 45271c3f35SPaul Mackerras #include <asm/vdso_datapage.h> 468d089085SBenjamin Herrenschmidt #include <asm/cputhreads.h> 470b05ac6eSBenjamin Herrenschmidt #include <asm/mpic.h> 480b05ac6eSBenjamin Herrenschmidt #include <asm/xics.h> 4969a80d3fSPaul Mackerras 50a1218720SMichael Ellerman #include "plpar_wrappers.h" 518feaeca2SMichael Ellerman #include "pseries.h" 523aa565f5SGautham R Shenoy #include "offline_states.h" 53a1218720SMichael Ellerman 5469a80d3fSPaul Mackerras 5569a80d3fSPaul Mackerras /* 566a75a6b8SMilton Miller * The Primary thread of each non-boot processor was started from the OF client 576a75a6b8SMilton Miller * interface by prom_hold_cpus and is spinning on secondary_hold_spinloop. 5869a80d3fSPaul Mackerras */ 59af831e1eSAnton Blanchard static cpumask_var_t of_spin_mask; 6069a80d3fSPaul Mackerras 61f8b67691SMichael Neuling /* Query where a cpu is now. Return codes #defined in plpar_wrappers.h */ 62f8b67691SMichael Neuling int smp_query_cpu_stopped(unsigned int pcpu) 63f8b67691SMichael Neuling { 64f8b67691SMichael Neuling int cpu_status, status; 65f8b67691SMichael Neuling int qcss_tok = rtas_token("query-cpu-stopped-state"); 66f8b67691SMichael Neuling 67f8b67691SMichael Neuling if (qcss_tok == RTAS_UNKNOWN_SERVICE) { 682d86938aSMilton Miller printk_once(KERN_INFO 692d86938aSMilton Miller "Firmware doesn't support query-cpu-stopped-state\n"); 70f8b67691SMichael Neuling return QCSS_HARDWARE_ERROR; 71f8b67691SMichael Neuling } 72f8b67691SMichael Neuling 73f8b67691SMichael Neuling status = rtas_call(qcss_tok, 1, 2, &cpu_status, pcpu); 74f8b67691SMichael Neuling if (status != 0) { 75f8b67691SMichael Neuling printk(KERN_ERR 76f8b67691SMichael Neuling "RTAS query-cpu-stopped-state failed: %i\n", status); 77f8b67691SMichael Neuling return status; 78f8b67691SMichael Neuling } 79f8b67691SMichael Neuling 80f8b67691SMichael Neuling return cpu_status; 81f8b67691SMichael Neuling } 82f8b67691SMichael Neuling 8369a80d3fSPaul Mackerras /** 8469a80d3fSPaul Mackerras * smp_startup_cpu() - start the given cpu 8569a80d3fSPaul Mackerras * 8669a80d3fSPaul Mackerras * At boot time, there is nothing to do for primary threads which were 8769a80d3fSPaul Mackerras * started from Open Firmware. For anything else, call RTAS with the 8869a80d3fSPaul Mackerras * appropriate start location. 8969a80d3fSPaul Mackerras * 9069a80d3fSPaul Mackerras * Returns: 9169a80d3fSPaul Mackerras * 0 - failure 9269a80d3fSPaul Mackerras * 1 - success 9369a80d3fSPaul Mackerras */ 9469a80d3fSPaul Mackerras static inline int __devinit smp_startup_cpu(unsigned int lcpu) 9569a80d3fSPaul Mackerras { 9669a80d3fSPaul Mackerras int status; 9769a80d3fSPaul Mackerras unsigned long start_here = __pa((u32)*((unsigned long *) 98f39b7a55SOlof Johansson generic_secondary_smp_init)); 9969a80d3fSPaul Mackerras unsigned int pcpu; 10069a80d3fSPaul Mackerras int start_cpu; 10169a80d3fSPaul Mackerras 102af831e1eSAnton Blanchard if (cpumask_test_cpu(lcpu, of_spin_mask)) 10369a80d3fSPaul Mackerras /* Already started by OF and sitting in spin loop */ 10469a80d3fSPaul Mackerras return 1; 10569a80d3fSPaul Mackerras 10669a80d3fSPaul Mackerras pcpu = get_hard_smp_processor_id(lcpu); 10769a80d3fSPaul Mackerras 108aef40e87SMichael Neuling /* Check to see if the CPU out of FW already for kexec */ 109aef40e87SMichael Neuling if (smp_query_cpu_stopped(pcpu) == QCSS_NOT_STOPPED){ 110af831e1eSAnton Blanchard cpumask_set_cpu(lcpu, of_spin_mask); 111aef40e87SMichael Neuling return 1; 112aef40e87SMichael Neuling } 113aef40e87SMichael Neuling 11469a80d3fSPaul Mackerras /* Fixup atomic count: it exited inside IRQ handler. */ 115b5e2fc1cSAl Viro task_thread_info(paca[lcpu].__current)->preempt_count = 0; 116c60e65d7SMatt Evans #ifdef CONFIG_HOTPLUG_CPU 1173aa565f5SGautham R Shenoy if (get_cpu_current_state(lcpu) == CPU_STATE_INACTIVE) 1183aa565f5SGautham R Shenoy goto out; 119c60e65d7SMatt Evans #endif 12069a80d3fSPaul Mackerras /* 12169a80d3fSPaul Mackerras * If the RTAS start-cpu token does not exist then presume the 12269a80d3fSPaul Mackerras * cpu is already spinning. 12369a80d3fSPaul Mackerras */ 12469a80d3fSPaul Mackerras start_cpu = rtas_token("start-cpu"); 12569a80d3fSPaul Mackerras if (start_cpu == RTAS_UNKNOWN_SERVICE) 12669a80d3fSPaul Mackerras return 1; 12769a80d3fSPaul Mackerras 128496b7a51SMichael Ellerman status = rtas_call(start_cpu, 3, 1, NULL, pcpu, start_here, pcpu); 12969a80d3fSPaul Mackerras if (status != 0) { 13069a80d3fSPaul Mackerras printk(KERN_ERR "start-cpu failed: %i\n", status); 13169a80d3fSPaul Mackerras return 0; 13269a80d3fSPaul Mackerras } 13369a80d3fSPaul Mackerras 134c60e65d7SMatt Evans #ifdef CONFIG_HOTPLUG_CPU 1353aa565f5SGautham R Shenoy out: 136c60e65d7SMatt Evans #endif 13769a80d3fSPaul Mackerras return 1; 13869a80d3fSPaul Mackerras } 13969a80d3fSPaul Mackerras 14069a80d3fSPaul Mackerras static void __devinit smp_xics_setup_cpu(int cpu) 14169a80d3fSPaul Mackerras { 14269a80d3fSPaul Mackerras if (cpu != boot_cpuid) 14369a80d3fSPaul Mackerras xics_setup_cpu(); 14469a80d3fSPaul Mackerras 14569a80d3fSPaul Mackerras if (firmware_has_feature(FW_FEATURE_SPLPAR)) 14669a80d3fSPaul Mackerras vpa_init(cpu); 14769a80d3fSPaul Mackerras 148af831e1eSAnton Blanchard cpumask_clear_cpu(cpu, of_spin_mask); 149c60e65d7SMatt Evans #ifdef CONFIG_HOTPLUG_CPU 1503aa565f5SGautham R Shenoy set_cpu_current_state(cpu, CPU_STATE_ONLINE); 1513aa565f5SGautham R Shenoy set_default_offline_state(cpu); 152c60e65d7SMatt Evans #endif 15369a80d3fSPaul Mackerras } 15469a80d3fSPaul Mackerras 15569a80d3fSPaul Mackerras static void __devinit smp_pSeries_kick_cpu(int nr) 15669a80d3fSPaul Mackerras { 15769a80d3fSPaul Mackerras BUG_ON(nr < 0 || nr >= NR_CPUS); 15869a80d3fSPaul Mackerras 15969a80d3fSPaul Mackerras if (!smp_startup_cpu(nr)) 16069a80d3fSPaul Mackerras return; 16169a80d3fSPaul Mackerras 16269a80d3fSPaul Mackerras /* 16369a80d3fSPaul Mackerras * The processor is currently spinning, waiting for the 16469a80d3fSPaul Mackerras * cpu_start field to become non-zero After we set cpu_start, 16569a80d3fSPaul Mackerras * the processor will continue on to secondary_start 16669a80d3fSPaul Mackerras */ 16769a80d3fSPaul Mackerras paca[nr].cpu_start = 1; 168c60e65d7SMatt Evans #ifdef CONFIG_HOTPLUG_CPU 1693aa565f5SGautham R Shenoy set_preferred_offline_state(nr, CPU_STATE_ONLINE); 1703aa565f5SGautham R Shenoy 1713aa565f5SGautham R Shenoy if (get_cpu_current_state(nr) == CPU_STATE_INACTIVE) { 172c60e65d7SMatt Evans long rc; 173c60e65d7SMatt Evans unsigned long hcpuid; 174c60e65d7SMatt Evans 1753aa565f5SGautham R Shenoy hcpuid = get_hard_smp_processor_id(nr); 1763aa565f5SGautham R Shenoy rc = plpar_hcall_norets(H_PROD, hcpuid); 1773aa565f5SGautham R Shenoy if (rc != H_SUCCESS) 1785a2ad98eSJoe Perches printk(KERN_ERR "Error: Prod to wake up processor %d " 1795a2ad98eSJoe Perches "Ret= %ld\n", nr, rc); 1803aa565f5SGautham R Shenoy } 181c60e65d7SMatt Evans #endif 18269a80d3fSPaul Mackerras } 18369a80d3fSPaul Mackerras 18469a80d3fSPaul Mackerras static int smp_pSeries_cpu_bootable(unsigned int nr) 18569a80d3fSPaul Mackerras { 18669a80d3fSPaul Mackerras /* Special case - we inhibit secondary thread startup 1876a75a6b8SMilton Miller * during boot if the user requests it. 18869a80d3fSPaul Mackerras */ 189954e6da5SNathan Fontenot if (system_state < SYSTEM_RUNNING && cpu_has_feature(CPU_FTR_SMT)) { 190954e6da5SNathan Fontenot if (!smt_enabled_at_boot && cpu_thread_in_core(nr) != 0) 19169a80d3fSPaul Mackerras return 0; 192954e6da5SNathan Fontenot if (smt_enabled_at_boot 193954e6da5SNathan Fontenot && cpu_thread_in_core(nr) >= smt_enabled_at_boot) 194954e6da5SNathan Fontenot return 0; 195954e6da5SNathan Fontenot } 19669a80d3fSPaul Mackerras 19769a80d3fSPaul Mackerras return 1; 19869a80d3fSPaul Mackerras } 1990b05ac6eSBenjamin Herrenschmidt 20069a80d3fSPaul Mackerras static struct smp_ops_t pSeries_mpic_smp_ops = { 20169a80d3fSPaul Mackerras .message_pass = smp_mpic_message_pass, 20269a80d3fSPaul Mackerras .probe = smp_mpic_probe, 20369a80d3fSPaul Mackerras .kick_cpu = smp_pSeries_kick_cpu, 20469a80d3fSPaul Mackerras .setup_cpu = smp_mpic_setup_cpu, 20569a80d3fSPaul Mackerras }; 2060b05ac6eSBenjamin Herrenschmidt 20769a80d3fSPaul Mackerras static struct smp_ops_t pSeries_xics_smp_ops = { 2080b05ac6eSBenjamin Herrenschmidt .message_pass = NULL, /* Filled at runtime by xics_smp_probe() */ 2090b05ac6eSBenjamin Herrenschmidt .probe = xics_smp_probe, 21069a80d3fSPaul Mackerras .kick_cpu = smp_pSeries_kick_cpu, 21169a80d3fSPaul Mackerras .setup_cpu = smp_xics_setup_cpu, 21269a80d3fSPaul Mackerras .cpu_bootable = smp_pSeries_cpu_bootable, 21369a80d3fSPaul Mackerras }; 21469a80d3fSPaul Mackerras 21569a80d3fSPaul Mackerras /* This is called very early */ 2160ebfff14SBenjamin Herrenschmidt static void __init smp_init_pseries(void) 21769a80d3fSPaul Mackerras { 21869a80d3fSPaul Mackerras int i; 21969a80d3fSPaul Mackerras 220f7ebf352SMichael Ellerman pr_debug(" -> smp_init_pSeries()\n"); 22169a80d3fSPaul Mackerras 222af831e1eSAnton Blanchard alloc_bootmem_cpumask_var(&of_spin_mask); 223af831e1eSAnton Blanchard 22469a80d3fSPaul Mackerras /* Mark threads which are still spinning in hold loops. */ 22569a80d3fSPaul Mackerras if (cpu_has_feature(CPU_FTR_SMT)) { 22669a80d3fSPaul Mackerras for_each_present_cpu(i) { 2276a75a6b8SMilton Miller if (cpu_thread_in_core(i) == 0) 228af831e1eSAnton Blanchard cpumask_set_cpu(i, of_spin_mask); 22969a80d3fSPaul Mackerras } 23069a80d3fSPaul Mackerras } else { 231af831e1eSAnton Blanchard cpumask_copy(of_spin_mask, cpu_present_mask); 23269a80d3fSPaul Mackerras } 23369a80d3fSPaul Mackerras 234af831e1eSAnton Blanchard cpumask_clear_cpu(boot_cpuid, of_spin_mask); 23569a80d3fSPaul Mackerras 23669a80d3fSPaul Mackerras /* Non-lpar has additional take/give timebase */ 23769a80d3fSPaul Mackerras if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) { 238c4007a2fSBenjamin Herrenschmidt smp_ops->give_timebase = rtas_give_timebase; 239c4007a2fSBenjamin Herrenschmidt smp_ops->take_timebase = rtas_take_timebase; 24069a80d3fSPaul Mackerras } 24169a80d3fSPaul Mackerras 242f7ebf352SMichael Ellerman pr_debug(" <- smp_init_pSeries()\n"); 24369a80d3fSPaul Mackerras } 24469a80d3fSPaul Mackerras 2450ebfff14SBenjamin Herrenschmidt void __init smp_init_pseries_mpic(void) 2460ebfff14SBenjamin Herrenschmidt { 2470ebfff14SBenjamin Herrenschmidt smp_ops = &pSeries_mpic_smp_ops; 2480ebfff14SBenjamin Herrenschmidt 2490ebfff14SBenjamin Herrenschmidt smp_init_pseries(); 2500ebfff14SBenjamin Herrenschmidt } 2510ebfff14SBenjamin Herrenschmidt 2520ebfff14SBenjamin Herrenschmidt void __init smp_init_pseries_xics(void) 2530ebfff14SBenjamin Herrenschmidt { 2540ebfff14SBenjamin Herrenschmidt smp_ops = &pSeries_xics_smp_ops; 2550ebfff14SBenjamin Herrenschmidt 2560ebfff14SBenjamin Herrenschmidt smp_init_pseries(); 2570ebfff14SBenjamin Herrenschmidt } 258