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 25 #include <asm/mmu_context.h> 26 #include <asm/io.h> 27 #include <asm/fw/cfe/cfe_api.h> 28 #include <asm/sibyte/sb1250.h> 29 #include <asm/sibyte/sb1250_regs.h> 30 #include <asm/sibyte/sb1250_int.h> 31 32 static void *mailbox_set_regs[] = { 33 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_SET_CPU), 34 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_SET_CPU) 35 }; 36 37 static void *mailbox_clear_regs[] = { 38 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CLR_CPU), 39 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CLR_CPU) 40 }; 41 42 static void *mailbox_regs[] = { 43 IOADDR(A_IMR_CPU0_BASE + R_IMR_MAILBOX_CPU), 44 IOADDR(A_IMR_CPU1_BASE + R_IMR_MAILBOX_CPU) 45 }; 46 47 /* 48 * SMP init and finish on secondary CPUs 49 */ 50 void __cpuinit sb1250_smp_init(void) 51 { 52 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 | 53 STATUSF_IP1 | STATUSF_IP0; 54 55 /* Set interrupt mask, but don't enable */ 56 change_c0_status(ST0_IM, imask); 57 } 58 59 /* 60 * These are routines for dealing with the sb1250 smp capabilities 61 * independent of board/firmware 62 */ 63 64 /* 65 * Simple enough; everything is set up, so just poke the appropriate mailbox 66 * register, and we should be set 67 */ 68 static void sb1250_send_ipi_single(int cpu, unsigned int action) 69 { 70 __raw_writeq((((u64)action) << 48), mailbox_set_regs[cpu]); 71 } 72 73 static inline void sb1250_send_ipi_mask(const struct cpumask *mask, 74 unsigned int action) 75 { 76 unsigned int i; 77 78 for_each_cpu(i, mask) 79 sb1250_send_ipi_single(i, action); 80 } 81 82 /* 83 * Code to run on secondary just after probing the CPU 84 */ 85 static void __cpuinit sb1250_init_secondary(void) 86 { 87 extern void sb1250_smp_init(void); 88 89 sb1250_smp_init(); 90 } 91 92 /* 93 * Do any tidying up before marking online and running the idle 94 * loop 95 */ 96 static void __cpuinit sb1250_smp_finish(void) 97 { 98 extern void sb1250_clockevent_init(void); 99 100 sb1250_clockevent_init(); 101 local_irq_enable(); 102 } 103 104 /* 105 * Final cleanup after all secondaries booted 106 */ 107 static void sb1250_cpus_done(void) 108 { 109 } 110 111 /* 112 * Setup the PC, SP, and GP of a secondary processor and start it 113 * running! 114 */ 115 static void __cpuinit sb1250_boot_secondary(int cpu, struct task_struct *idle) 116 { 117 int retval; 118 119 retval = cfe_cpu_start(cpu_logical_map(cpu), &smp_bootstrap, 120 __KSTK_TOS(idle), 121 (unsigned long)task_thread_info(idle), 0); 122 if (retval != 0) 123 printk("cfe_start_cpu(%i) returned %i\n" , cpu, retval); 124 } 125 126 /* 127 * Use CFE to find out how many CPUs are available, setting up 128 * cpu_possible_map and the logical/physical mappings. 129 * XXXKW will the boot CPU ever not be physical 0? 130 * 131 * Common setup before any secondaries are started 132 */ 133 static void __init sb1250_smp_setup(void) 134 { 135 int i, num; 136 137 cpus_clear(cpu_possible_map); 138 cpu_set(0, cpu_possible_map); 139 __cpu_number_map[0] = 0; 140 __cpu_logical_map[0] = 0; 141 142 for (i = 1, num = 0; i < NR_CPUS; i++) { 143 if (cfe_cpu_stop(i) == 0) { 144 cpu_set(i, cpu_possible_map); 145 __cpu_number_map[i] = ++num; 146 __cpu_logical_map[num] = i; 147 } 148 } 149 printk(KERN_INFO "Detected %i available secondary CPU(s)\n", num); 150 } 151 152 static void __init sb1250_prepare_cpus(unsigned int max_cpus) 153 { 154 } 155 156 struct plat_smp_ops sb_smp_ops = { 157 .send_ipi_single = sb1250_send_ipi_single, 158 .send_ipi_mask = sb1250_send_ipi_mask, 159 .init_secondary = sb1250_init_secondary, 160 .smp_finish = sb1250_smp_finish, 161 .cpus_done = sb1250_cpus_done, 162 .boot_secondary = sb1250_boot_secondary, 163 .smp_setup = sb1250_smp_setup, 164 .prepare_cpus = sb1250_prepare_cpus, 165 }; 166 167 void sb1250_mailbox_interrupt(void) 168 { 169 int cpu = smp_processor_id(); 170 int irq = K_INT_MBOX_0; 171 unsigned int action; 172 173 kstat_incr_irqs_this_cpu(irq, irq_to_desc(irq)); 174 /* Load the mailbox register to figure out what we're supposed to do */ 175 action = (____raw_readq(mailbox_regs[cpu]) >> 48) & 0xffff; 176 177 /* Clear the mailbox to clear the interrupt */ 178 ____raw_writeq(((u64)action) << 48, mailbox_clear_regs[cpu]); 179 180 /* 181 * Nothing to do for SMP_RESCHEDULE_YOURSELF; returning from the 182 * interrupt will do the reschedule for us 183 */ 184 185 if (action & SMP_CALL_FUNCTION) 186 smp_call_function_interrupt(); 187 } 188