1 /* 2 * This program is free software; you can distribute it and/or modify it 3 * under the terms of the GNU General Public License (Version 2) as 4 * published by the Free Software Foundation. 5 * 6 * This program is distributed in the hope it will be useful, but WITHOUT 7 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 8 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 9 * for more details. 10 * 11 * You should have received a copy of the GNU General Public License along 12 * with this program; if not, write to the Free Software Foundation, Inc., 13 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. 14 * 15 * Copyright (C) 2004, 05, 06 MIPS Technologies, Inc. 16 * Elizabeth Clarke (beth@mips.com) 17 * Ralf Baechle (ralf@linux-mips.org) 18 * Copyright (C) 2006 Ralf Baechle (ralf@linux-mips.org) 19 */ 20 #include <linux/kernel.h> 21 #include <linux/sched.h> 22 #include <linux/cpumask.h> 23 #include <linux/interrupt.h> 24 #include <linux/irqchip/mips-gic.h> 25 #include <linux/compiler.h> 26 #include <linux/smp.h> 27 28 #include <linux/atomic.h> 29 #include <asm/cacheflush.h> 30 #include <asm/cpu.h> 31 #include <asm/processor.h> 32 #include <asm/hardirq.h> 33 #include <asm/mmu_context.h> 34 #include <asm/time.h> 35 #include <asm/mipsregs.h> 36 #include <asm/mipsmtregs.h> 37 #include <asm/mips_mt.h> 38 39 static void __init smvp_copy_vpe_config(void) 40 { 41 write_vpe_c0_status( 42 (read_c0_status() & ~(ST0_IM | ST0_IE | ST0_KSU)) | ST0_CU0); 43 44 /* set config to be the same as vpe0, particularly kseg0 coherency alg */ 45 write_vpe_c0_config( read_c0_config()); 46 47 /* make sure there are no software interrupts pending */ 48 write_vpe_c0_cause(0); 49 50 /* Propagate Config7 */ 51 write_vpe_c0_config7(read_c0_config7()); 52 53 write_vpe_c0_count(read_c0_count()); 54 } 55 56 static unsigned int __init smvp_vpe_init(unsigned int tc, unsigned int mvpconf0, 57 unsigned int ncpu) 58 { 59 if (tc > ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)) 60 return ncpu; 61 62 /* Deactivate all but VPE 0 */ 63 if (tc != 0) { 64 unsigned long tmp = read_vpe_c0_vpeconf0(); 65 66 tmp &= ~VPECONF0_VPA; 67 68 /* master VPE */ 69 tmp |= VPECONF0_MVP; 70 write_vpe_c0_vpeconf0(tmp); 71 72 /* Record this as available CPU */ 73 set_cpu_possible(tc, true); 74 set_cpu_present(tc, true); 75 __cpu_number_map[tc] = ++ncpu; 76 __cpu_logical_map[ncpu] = tc; 77 } 78 79 /* Disable multi-threading with TC's */ 80 write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE); 81 82 if (tc != 0) 83 smvp_copy_vpe_config(); 84 85 return ncpu; 86 } 87 88 static void __init smvp_tc_init(unsigned int tc, unsigned int mvpconf0) 89 { 90 unsigned long tmp; 91 92 if (!tc) 93 return; 94 95 /* bind a TC to each VPE, May as well put all excess TC's 96 on the last VPE */ 97 if (tc >= (((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)+1)) 98 write_tc_c0_tcbind(read_tc_c0_tcbind() | ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)); 99 else { 100 write_tc_c0_tcbind(read_tc_c0_tcbind() | tc); 101 102 /* and set XTC */ 103 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | (tc << VPECONF0_XTC_SHIFT)); 104 } 105 106 tmp = read_tc_c0_tcstatus(); 107 108 /* mark not allocated and not dynamically allocatable */ 109 tmp &= ~(TCSTATUS_A | TCSTATUS_DA); 110 tmp |= TCSTATUS_IXMT; /* interrupt exempt */ 111 write_tc_c0_tcstatus(tmp); 112 113 write_tc_c0_tchalt(TCHALT_H); 114 } 115 116 static void vsmp_send_ipi_single(int cpu, unsigned int action) 117 { 118 int i; 119 unsigned long flags; 120 int vpflags; 121 122 #ifdef CONFIG_MIPS_GIC 123 if (gic_present) { 124 mips_smp_send_ipi_single(cpu, action); 125 return; 126 } 127 #endif 128 local_irq_save(flags); 129 130 vpflags = dvpe(); /* can't access the other CPU's registers whilst MVPE enabled */ 131 132 switch (action) { 133 case SMP_CALL_FUNCTION: 134 i = C_SW1; 135 break; 136 137 case SMP_RESCHEDULE_YOURSELF: 138 default: 139 i = C_SW0; 140 break; 141 } 142 143 /* 1:1 mapping of vpe and tc... */ 144 settc(cpu); 145 write_vpe_c0_cause(read_vpe_c0_cause() | i); 146 evpe(vpflags); 147 148 local_irq_restore(flags); 149 } 150 151 static void vsmp_send_ipi_mask(const struct cpumask *mask, unsigned int action) 152 { 153 unsigned int i; 154 155 for_each_cpu(i, mask) 156 vsmp_send_ipi_single(i, action); 157 } 158 159 static void vsmp_init_secondary(void) 160 { 161 #ifdef CONFIG_MIPS_GIC 162 /* This is Malta specific: IPI,performance and timer interrupts */ 163 if (gic_present) 164 change_c0_status(ST0_IM, STATUSF_IP2 | STATUSF_IP3 | 165 STATUSF_IP4 | STATUSF_IP5 | 166 STATUSF_IP6 | STATUSF_IP7); 167 else 168 #endif 169 change_c0_status(ST0_IM, STATUSF_IP0 | STATUSF_IP1 | 170 STATUSF_IP6 | STATUSF_IP7); 171 } 172 173 static void vsmp_smp_finish(void) 174 { 175 /* CDFIXME: remove this? */ 176 write_c0_compare(read_c0_count() + (8* mips_hpt_frequency/HZ)); 177 178 #ifdef CONFIG_MIPS_MT_FPAFF 179 /* If we have an FPU, enroll ourselves in the FPU-full mask */ 180 if (cpu_has_fpu) 181 cpumask_set_cpu(smp_processor_id(), &mt_fpu_cpumask); 182 #endif /* CONFIG_MIPS_MT_FPAFF */ 183 184 local_irq_enable(); 185 } 186 187 /* 188 * Setup the PC, SP, and GP of a secondary processor and start it 189 * running! 190 * smp_bootstrap is the place to resume from 191 * __KSTK_TOS(idle) is apparently the stack pointer 192 * (unsigned long)idle->thread_info the gp 193 * assumes a 1:1 mapping of TC => VPE 194 */ 195 static void vsmp_boot_secondary(int cpu, struct task_struct *idle) 196 { 197 struct thread_info *gp = task_thread_info(idle); 198 dvpe(); 199 set_c0_mvpcontrol(MVPCONTROL_VPC); 200 201 settc(cpu); 202 203 /* restart */ 204 write_tc_c0_tcrestart((unsigned long)&smp_bootstrap); 205 206 /* enable the tc this vpe/cpu will be running */ 207 write_tc_c0_tcstatus((read_tc_c0_tcstatus() & ~TCSTATUS_IXMT) | TCSTATUS_A); 208 209 write_tc_c0_tchalt(0); 210 211 /* enable the VPE */ 212 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA); 213 214 /* stack pointer */ 215 write_tc_gpr_sp( __KSTK_TOS(idle)); 216 217 /* global pointer */ 218 write_tc_gpr_gp((unsigned long)gp); 219 220 flush_icache_range((unsigned long)gp, 221 (unsigned long)(gp + sizeof(struct thread_info))); 222 223 /* finally out of configuration and into chaos */ 224 clear_c0_mvpcontrol(MVPCONTROL_VPC); 225 226 evpe(EVPE_ENABLE); 227 } 228 229 /* 230 * Common setup before any secondaries are started 231 * Make sure all CPU's are in a sensible state before we boot any of the 232 * secondaries 233 */ 234 static void __init vsmp_smp_setup(void) 235 { 236 unsigned int mvpconf0, ntc, tc, ncpu = 0; 237 unsigned int nvpe; 238 239 #ifdef CONFIG_MIPS_MT_FPAFF 240 /* If we have an FPU, enroll ourselves in the FPU-full mask */ 241 if (cpu_has_fpu) 242 cpumask_set_cpu(0, &mt_fpu_cpumask); 243 #endif /* CONFIG_MIPS_MT_FPAFF */ 244 if (!cpu_has_mipsmt) 245 return; 246 247 /* disable MT so we can configure */ 248 dvpe(); 249 dmt(); 250 251 /* Put MVPE's into 'configuration state' */ 252 set_c0_mvpcontrol(MVPCONTROL_VPC); 253 254 mvpconf0 = read_c0_mvpconf0(); 255 ntc = (mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT; 256 257 nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1; 258 smp_num_siblings = nvpe; 259 260 /* we'll always have more TC's than VPE's, so loop setting everything 261 to a sensible state */ 262 for (tc = 0; tc <= ntc; tc++) { 263 settc(tc); 264 265 smvp_tc_init(tc, mvpconf0); 266 ncpu = smvp_vpe_init(tc, mvpconf0, ncpu); 267 } 268 269 /* Release config state */ 270 clear_c0_mvpcontrol(MVPCONTROL_VPC); 271 272 /* We'll wait until starting the secondaries before starting MVPE */ 273 274 printk(KERN_INFO "Detected %i available secondary CPU(s)\n", ncpu); 275 } 276 277 static void __init vsmp_prepare_cpus(unsigned int max_cpus) 278 { 279 mips_mt_set_cpuoptions(); 280 } 281 282 struct plat_smp_ops vsmp_smp_ops = { 283 .send_ipi_single = vsmp_send_ipi_single, 284 .send_ipi_mask = vsmp_send_ipi_mask, 285 .init_secondary = vsmp_init_secondary, 286 .smp_finish = vsmp_smp_finish, 287 .boot_secondary = vsmp_boot_secondary, 288 .smp_setup = vsmp_smp_setup, 289 .prepare_cpus = vsmp_prepare_cpus, 290 }; 291 292