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/compiler.h> 25 #include <linux/smp.h> 26 27 #include <linux/atomic.h> 28 #include <asm/cacheflush.h> 29 #include <asm/cpu.h> 30 #include <asm/processor.h> 31 #include <asm/system.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 __cpu_number_map[tc] = ++ncpu; 75 __cpu_logical_map[ncpu] = tc; 76 } 77 78 /* Disable multi-threading with TC's */ 79 write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE); 80 81 if (tc != 0) 82 smvp_copy_vpe_config(); 83 84 return ncpu; 85 } 86 87 static void __init smvp_tc_init(unsigned int tc, unsigned int mvpconf0) 88 { 89 unsigned long tmp; 90 91 if (!tc) 92 return; 93 94 /* bind a TC to each VPE, May as well put all excess TC's 95 on the last VPE */ 96 if (tc >= (((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)+1)) 97 write_tc_c0_tcbind(read_tc_c0_tcbind() | ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT)); 98 else { 99 write_tc_c0_tcbind(read_tc_c0_tcbind() | tc); 100 101 /* and set XTC */ 102 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | (tc << VPECONF0_XTC_SHIFT)); 103 } 104 105 tmp = read_tc_c0_tcstatus(); 106 107 /* mark not allocated and not dynamically allocatable */ 108 tmp &= ~(TCSTATUS_A | TCSTATUS_DA); 109 tmp |= TCSTATUS_IXMT; /* interrupt exempt */ 110 write_tc_c0_tcstatus(tmp); 111 112 write_tc_c0_tchalt(TCHALT_H); 113 } 114 115 static void vsmp_send_ipi_single(int cpu, unsigned int action) 116 { 117 int i; 118 unsigned long flags; 119 int vpflags; 120 121 local_irq_save(flags); 122 123 vpflags = dvpe(); /* can't access the other CPU's registers whilst MVPE enabled */ 124 125 switch (action) { 126 case SMP_CALL_FUNCTION: 127 i = C_SW1; 128 break; 129 130 case SMP_RESCHEDULE_YOURSELF: 131 default: 132 i = C_SW0; 133 break; 134 } 135 136 /* 1:1 mapping of vpe and tc... */ 137 settc(cpu); 138 write_vpe_c0_cause(read_vpe_c0_cause() | i); 139 evpe(vpflags); 140 141 local_irq_restore(flags); 142 } 143 144 static void vsmp_send_ipi_mask(const struct cpumask *mask, unsigned int action) 145 { 146 unsigned int i; 147 148 for_each_cpu(i, mask) 149 vsmp_send_ipi_single(i, action); 150 } 151 152 static void __cpuinit vsmp_init_secondary(void) 153 { 154 extern int gic_present; 155 156 /* This is Malta specific: IPI,performance and timer interrupts */ 157 if (gic_present) 158 change_c0_status(ST0_IM, STATUSF_IP3 | STATUSF_IP4 | 159 STATUSF_IP6 | STATUSF_IP7); 160 else 161 change_c0_status(ST0_IM, STATUSF_IP0 | STATUSF_IP1 | 162 STATUSF_IP6 | STATUSF_IP7); 163 } 164 165 static void __cpuinit vsmp_smp_finish(void) 166 { 167 /* CDFIXME: remove this? */ 168 write_c0_compare(read_c0_count() + (8* mips_hpt_frequency/HZ)); 169 170 #ifdef CONFIG_MIPS_MT_FPAFF 171 /* If we have an FPU, enroll ourselves in the FPU-full mask */ 172 if (cpu_has_fpu) 173 cpu_set(smp_processor_id(), mt_fpu_cpumask); 174 #endif /* CONFIG_MIPS_MT_FPAFF */ 175 176 local_irq_enable(); 177 } 178 179 static void vsmp_cpus_done(void) 180 { 181 } 182 183 /* 184 * Setup the PC, SP, and GP of a secondary processor and start it 185 * running! 186 * smp_bootstrap is the place to resume from 187 * __KSTK_TOS(idle) is apparently the stack pointer 188 * (unsigned long)idle->thread_info the gp 189 * assumes a 1:1 mapping of TC => VPE 190 */ 191 static void __cpuinit vsmp_boot_secondary(int cpu, struct task_struct *idle) 192 { 193 struct thread_info *gp = task_thread_info(idle); 194 dvpe(); 195 set_c0_mvpcontrol(MVPCONTROL_VPC); 196 197 settc(cpu); 198 199 /* restart */ 200 write_tc_c0_tcrestart((unsigned long)&smp_bootstrap); 201 202 /* enable the tc this vpe/cpu will be running */ 203 write_tc_c0_tcstatus((read_tc_c0_tcstatus() & ~TCSTATUS_IXMT) | TCSTATUS_A); 204 205 write_tc_c0_tchalt(0); 206 207 /* enable the VPE */ 208 write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA); 209 210 /* stack pointer */ 211 write_tc_gpr_sp( __KSTK_TOS(idle)); 212 213 /* global pointer */ 214 write_tc_gpr_gp((unsigned long)gp); 215 216 flush_icache_range((unsigned long)gp, 217 (unsigned long)(gp + sizeof(struct thread_info))); 218 219 /* finally out of configuration and into chaos */ 220 clear_c0_mvpcontrol(MVPCONTROL_VPC); 221 222 evpe(EVPE_ENABLE); 223 } 224 225 /* 226 * Common setup before any secondaries are started 227 * Make sure all CPU's are in a sensible state before we boot any of the 228 * secondaries 229 */ 230 static void __init vsmp_smp_setup(void) 231 { 232 unsigned int mvpconf0, ntc, tc, ncpu = 0; 233 unsigned int nvpe; 234 235 #ifdef CONFIG_MIPS_MT_FPAFF 236 /* If we have an FPU, enroll ourselves in the FPU-full mask */ 237 if (cpu_has_fpu) 238 cpu_set(0, mt_fpu_cpumask); 239 #endif /* CONFIG_MIPS_MT_FPAFF */ 240 if (!cpu_has_mipsmt) 241 return; 242 243 /* disable MT so we can configure */ 244 dvpe(); 245 dmt(); 246 247 /* Put MVPE's into 'configuration state' */ 248 set_c0_mvpcontrol(MVPCONTROL_VPC); 249 250 mvpconf0 = read_c0_mvpconf0(); 251 ntc = (mvpconf0 & MVPCONF0_PTC) >> MVPCONF0_PTC_SHIFT; 252 253 nvpe = ((mvpconf0 & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1; 254 smp_num_siblings = nvpe; 255 256 /* we'll always have more TC's than VPE's, so loop setting everything 257 to a sensible state */ 258 for (tc = 0; tc <= ntc; tc++) { 259 settc(tc); 260 261 smvp_tc_init(tc, mvpconf0); 262 ncpu = smvp_vpe_init(tc, mvpconf0, ncpu); 263 } 264 265 /* Release config state */ 266 clear_c0_mvpcontrol(MVPCONTROL_VPC); 267 268 /* We'll wait until starting the secondaries before starting MVPE */ 269 270 printk(KERN_INFO "Detected %i available secondary CPU(s)\n", ncpu); 271 } 272 273 static void __init vsmp_prepare_cpus(unsigned int max_cpus) 274 { 275 mips_mt_set_cpuoptions(); 276 } 277 278 struct plat_smp_ops vsmp_smp_ops = { 279 .send_ipi_single = vsmp_send_ipi_single, 280 .send_ipi_mask = vsmp_send_ipi_mask, 281 .init_secondary = vsmp_init_secondary, 282 .smp_finish = vsmp_smp_finish, 283 .cpus_done = vsmp_cpus_done, 284 .boot_secondary = vsmp_boot_secondary, 285 .smp_setup = vsmp_smp_setup, 286 .prepare_cpus = vsmp_prepare_cpus, 287 }; 288