1/* 2 * Smp support for CHRP machines. 3 * 4 * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great 5 * deal of code from the sparc and intel versions. 6 * 7 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu> 8 * 9 */ 10 11#include <linux/kernel.h> 12#include <linux/sched.h> 13#include <linux/smp.h> 14#include <linux/interrupt.h> 15#include <linux/kernel_stat.h> 16#include <linux/delay.h> 17#include <linux/init.h> 18#include <linux/spinlock.h> 19 20#include <asm/ptrace.h> 21#include <asm/atomic.h> 22#include <asm/irq.h> 23#include <asm/page.h> 24#include <asm/pgtable.h> 25#include <asm/sections.h> 26#include <asm/io.h> 27#include <asm/prom.h> 28#include <asm/smp.h> 29#include <asm/residual.h> 30#include <asm/time.h> 31#include <asm/machdep.h> 32#include <asm/smp.h> 33#include <asm/mpic.h> 34#include <asm/rtas.h> 35 36static void __devinit smp_chrp_kick_cpu(int nr) 37{ 38 *(unsigned long *)KERNELBASE = nr; 39 asm volatile("dcbf 0,%0"::"r"(KERNELBASE):"memory"); 40} 41 42static void __devinit smp_chrp_setup_cpu(int cpu_nr) 43{ 44 mpic_setup_this_cpu(); 45} 46 47static DEFINE_SPINLOCK(timebase_lock); 48static unsigned int timebase_upper = 0, timebase_lower = 0; 49 50void __devinit smp_chrp_give_timebase(void) 51{ 52 spin_lock(&timebase_lock); 53 rtas_call(rtas_token("freeze-time-base"), 0, 1, NULL); 54 timebase_upper = get_tbu(); 55 timebase_lower = get_tbl(); 56 spin_unlock(&timebase_lock); 57 58 while (timebase_upper || timebase_lower) 59 barrier(); 60 rtas_call(rtas_token("thaw-time-base"), 0, 1, NULL); 61} 62 63void __devinit smp_chrp_take_timebase(void) 64{ 65 while (!(timebase_upper || timebase_lower)) 66 barrier(); 67 spin_lock(&timebase_lock); 68 set_tb(timebase_upper, timebase_lower); 69 timebase_upper = 0; 70 timebase_lower = 0; 71 spin_unlock(&timebase_lock); 72 printk("CPU %i taken timebase\n", smp_processor_id()); 73} 74 75/* CHRP with openpic */ 76struct smp_ops_t chrp_smp_ops = { 77 .message_pass = smp_mpic_message_pass, 78 .probe = smp_mpic_probe, 79 .kick_cpu = smp_chrp_kick_cpu, 80 .setup_cpu = smp_chrp_setup_cpu, 81 .give_timebase = smp_chrp_give_timebase, 82 .take_timebase = smp_chrp_take_timebase, 83}; 84