1 /* 2 * Copyright (C) 2001, 2002, 2003 Broadcom Corporation 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 2 7 * of the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 */ 18 19 #include <linux/init.h> 20 #include <linux/delay.h> 21 #include <linux/interrupt.h> 22 #include <linux/smp.h> 23 #include <linux/kernel_stat.h> 24 #include <linux/sched/task_stack.h> 25 26 #include <asm/mmu_context.h> 27 #include <asm/io.h> 28 #include <asm/fw/cfe/cfe_api.h> 29 #include <asm/sibyte/sb1250.h> 30 #include <asm/sibyte/sb1250_regs.h> 31 #include <asm/sibyte/sb1250_int.h> 32 33 static void *mailbox_set_regs[] = { 34 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_SET_CPU), 35 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_SET_CPU) 36 }; 37 38 static void *mailbox_clear_regs[] = { 39 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CLR_CPU), 40 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CLR_CPU) 41 }; 42 43 static void *mailbox_regs[] = { 44 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CPU), 45 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CPU) 46 }; 47 48 /* 49 * SMP init and finish on secondary CPUs 50 */ 51 void sb1250_smp_init(void) 52 { 53 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 | 54 STATUSF_IP1 | STATUSF_IP0; 55 56 /* Set interrupt mask, but don't enable */ 57 change_c0_status(ST0_IM, imask); 58 } 59 60 /* 61 * These are routines for dealing with the sb1250 smp capabilities 62 * independent of board/firmware 63 */ 64 65 /* 66 * Simple enough; everything is set up, so just poke the appropriate mailbox 67 * register, and we should be set 68 */ 69 static void sb1250_send_ipi_single(int cpu, unsigned int action) 70 { 71 __raw_writeq((((u64)action) << 48), mailbox_set_regs[cpu]); 72 } 73 74 static inline void sb1250_send_ipi_mask(const struct cpumask *mask, 75 unsigned int action) 76 { 77 unsigned int i; 78 79 for_each_cpu(i, mask) 80 sb1250_send_ipi_single(i, action); 81 } 82 83 /* 84 * Code to run on secondary just after probing the CPU 85 */ 86 static void sb1250_init_secondary(void) 87 { 88 extern void sb1250_smp_init(void); 89 90 sb1250_smp_init(); 91 } 92 93 /* 94 * Do any tidying up before marking online and running the idle 95 * loop 96 */ 97 static void sb1250_smp_finish(void) 98 { 99 extern void sb1250_clockevent_init(void); 100 101 sb1250_clockevent_init(); 102 local_irq_enable(); 103 } 104 105 /* 106 * Setup the PC, SP, and GP of a secondary processor and start it 107 * running! 108 */ 109 static int sb1250_boot_secondary(int cpu, struct task_struct *idle) 110 { 111 int retval; 112 113 retval = cfe_cpu_start(cpu_logical_map(cpu), &smp_bootstrap, 114 __KSTK_TOS(idle), 115 (unsigned long)task_thread_info(idle), 0); 116 if (retval != 0) 117 printk("cfe_start_cpu(%i) returned %i\n" , cpu, retval); 118 return retval; 119 } 120 121 /* 122 * Use CFE to find out how many CPUs are available, setting up 123 * cpu_possible_mask and the logical/physical mappings. 124 * XXXKW will the boot CPU ever not be physical 0? 125 * 126 * Common setup before any secondaries are started 127 */ 128 static void __init sb1250_smp_setup(void) 129 { 130 int i, num; 131 132 init_cpu_possible(cpumask_of(0)); 133 __cpu_number_map[0] = 0; 134 __cpu_logical_map[0] = 0; 135 136 for (i = 1, num = 0; i < NR_CPUS; i++) { 137 if (cfe_cpu_stop(i) == 0) { 138 set_cpu_possible(i, true); 139 __cpu_number_map[i] = ++num; 140 __cpu_logical_map[num] = i; 141 } 142 } 143 printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num); 144 } 145 146 static void __init sb1250_prepare_cpus(unsigned int max_cpus) 147 { 148 } 149 150 const struct plat_smp_ops sb_smp_ops = { 151 .send_ipi_single = sb1250_send_ipi_single, 152 .send_ipi_mask = sb1250_send_ipi_mask, 153 .init_secondary = sb1250_init_secondary, 154 .smp_finish = sb1250_smp_finish, 155 .boot_secondary = sb1250_boot_secondary, 156 .smp_setup = sb1250_smp_setup, 157 .prepare_cpus = sb1250_prepare_cpus, 158 }; 159 160 void sb1250_mailbox_interrupt(void) 161 { 162 int cpu = smp_processor_id(); 163 int irq = K_INT_MBOX_0; 164 unsigned int action; 165 166 kstat_incr_irq_this_cpu(irq); 167 /* Load the mailbox register to figure out what we're supposed to do */ 168 action = (____raw_readq(mailbox_regs[cpu]) >> 48) & 0xffff; 169 170 /* Clear the mailbox to clear the interrupt */ 171 ____raw_writeq(((u64)action) << 48, mailbox_clear_regs[cpu]); 172 173 if (action & SMP_RESCHEDULE_YOURSELF) 174 scheduler_ipi(); 175 176 if (action & SMP_CALL_FUNCTION) { 177 irq_enter(); 178 generic_smp_call_function_interrupt(); 179 irq_exit(); 180 } 181 } 182