| Benjamin Herrenschmidt | 55190f8 | 2011-09-19 17:44:52 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * SMP support for PowerNV machines. |
| 3 | * |
| 4 | * Copyright 2011 IBM Corp. |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License |
| 8 | * as published by the Free Software Foundation; either version |
| 9 | * 2 of the License, or (at your option) any later version. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/sched.h> |
| 15 | #include <linux/smp.h> |
| 16 | #include <linux/interrupt.h> |
| 17 | #include <linux/delay.h> |
| 18 | #include <linux/init.h> |
| 19 | #include <linux/spinlock.h> |
| 20 | #include <linux/cpu.h> |
| 21 | |
| 22 | #include <asm/irq.h> |
| 23 | #include <asm/smp.h> |
| 24 | #include <asm/paca.h> |
| 25 | #include <asm/machdep.h> |
| 26 | #include <asm/cputable.h> |
| 27 | #include <asm/firmware.h> |
| 28 | #include <asm/system.h> |
| 29 | #include <asm/rtas.h> |
| 30 | #include <asm/vdso_datapage.h> |
| 31 | #include <asm/cputhreads.h> |
| 32 | #include <asm/xics.h> |
| 33 | |
| 34 | #include "powernv.h" |
| 35 | |
| 36 | static void __devinit pnv_smp_setup_cpu(int cpu) |
| 37 | { |
| 38 | if (cpu != boot_cpuid) |
| 39 | xics_setup_cpu(); |
| 40 | } |
| 41 | |
| 42 | static int pnv_smp_cpu_bootable(unsigned int nr) |
| 43 | { |
| 44 | /* Special case - we inhibit secondary thread startup |
| 45 | * during boot if the user requests it. |
| 46 | */ |
| 47 | if (system_state < SYSTEM_RUNNING && cpu_has_feature(CPU_FTR_SMT)) { |
| 48 | if (!smt_enabled_at_boot && cpu_thread_in_core(nr) != 0) |
| 49 | return 0; |
| 50 | if (smt_enabled_at_boot |
| 51 | && cpu_thread_in_core(nr) >= smt_enabled_at_boot) |
| 52 | return 0; |
| 53 | } |
| 54 | |
| 55 | return 1; |
| 56 | } |
| 57 | |
| 58 | static struct smp_ops_t pnv_smp_ops = { |
| 59 | .message_pass = smp_muxed_ipi_message_pass, |
| 60 | .cause_ipi = NULL, /* Filled at runtime by xics_smp_probe() */ |
| 61 | .probe = xics_smp_probe, |
| 62 | .kick_cpu = smp_generic_kick_cpu, |
| 63 | .setup_cpu = pnv_smp_setup_cpu, |
| 64 | .cpu_bootable = pnv_smp_cpu_bootable, |
| 65 | }; |
| 66 | |
| 67 | /* This is called very early during platform setup_arch */ |
| 68 | void __init pnv_smp_init(void) |
| 69 | { |
| 70 | smp_ops = &pnv_smp_ops; |
| 71 | |
| 72 | /* XXX We don't yet have a proper entry point from HAL, for |
| 73 | * now we rely on kexec-style entry from BML |
| 74 | */ |
| 75 | |
| 76 | #ifdef CONFIG_PPC_RTAS |
| 77 | /* Non-lpar has additional take/give timebase */ |
| 78 | if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) { |
| 79 | smp_ops->give_timebase = rtas_give_timebase; |
| 80 | smp_ops->take_timebase = rtas_take_timebase; |
| 81 | } |
| 82 | #endif /* CONFIG_PPC_RTAS */ |
| 83 | } |