1 /* 2 * Copyright (C) 2000,2001,2002,2003,2004 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 #include <linux/kernel.h> 19 #include <linux/init.h> 20 #include <linux/linkage.h> 21 #include <linux/interrupt.h> 22 #include <linux/smp.h> 23 #include <linux/spinlock.h> 24 #include <linux/mm.h> 25 #include <linux/slab.h> 26 #include <linux/kernel_stat.h> 27 28 #include <asm/errno.h> 29 #include <asm/irq_regs.h> 30 #include <asm/signal.h> 31 #include <asm/system.h> 32 #include <asm/io.h> 33 34 #include <asm/sibyte/bcm1480_regs.h> 35 #include <asm/sibyte/bcm1480_int.h> 36 #include <asm/sibyte/bcm1480_scd.h> 37 38 #include <asm/sibyte/sb1250_uart.h> 39 #include <asm/sibyte/sb1250.h> 40 41 /* 42 * These are the routines that handle all the low level interrupt stuff. 43 * Actions handled here are: initialization of the interrupt map, requesting of 44 * interrupt lines by handlers, dispatching if interrupts to handlers, probing 45 * for interrupt lines 46 */ 47 48 49 static void end_bcm1480_irq(unsigned int irq); 50 static void enable_bcm1480_irq(unsigned int irq); 51 static void disable_bcm1480_irq(unsigned int irq); 52 static void ack_bcm1480_irq(unsigned int irq); 53 #ifdef CONFIG_SMP 54 static int bcm1480_set_affinity(unsigned int irq, const struct cpumask *mask); 55 #endif 56 57 #ifdef CONFIG_PCI 58 extern unsigned long ht_eoi_space; 59 #endif 60 61 static struct irq_chip bcm1480_irq_type = { 62 .name = "BCM1480-IMR", 63 .ack = ack_bcm1480_irq, 64 .mask = disable_bcm1480_irq, 65 .mask_ack = ack_bcm1480_irq, 66 .unmask = enable_bcm1480_irq, 67 .end = end_bcm1480_irq, 68 #ifdef CONFIG_SMP 69 .set_affinity = bcm1480_set_affinity 70 #endif 71 }; 72 73 /* Store the CPU id (not the logical number) */ 74 int bcm1480_irq_owner[BCM1480_NR_IRQS]; 75 76 DEFINE_SPINLOCK(bcm1480_imr_lock); 77 78 void bcm1480_mask_irq(int cpu, int irq) 79 { 80 unsigned long flags, hl_spacing; 81 u64 cur_ints; 82 83 spin_lock_irqsave(&bcm1480_imr_lock, flags); 84 hl_spacing = 0; 85 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) { 86 hl_spacing = BCM1480_IMR_HL_SPACING; 87 irq -= BCM1480_NR_IRQS_HALF; 88 } 89 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 90 cur_ints |= (((u64) 1) << irq); 91 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 92 spin_unlock_irqrestore(&bcm1480_imr_lock, flags); 93 } 94 95 void bcm1480_unmask_irq(int cpu, int irq) 96 { 97 unsigned long flags, hl_spacing; 98 u64 cur_ints; 99 100 spin_lock_irqsave(&bcm1480_imr_lock, flags); 101 hl_spacing = 0; 102 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) { 103 hl_spacing = BCM1480_IMR_HL_SPACING; 104 irq -= BCM1480_NR_IRQS_HALF; 105 } 106 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 107 cur_ints &= ~(((u64) 1) << irq); 108 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 109 spin_unlock_irqrestore(&bcm1480_imr_lock, flags); 110 } 111 112 #ifdef CONFIG_SMP 113 static int bcm1480_set_affinity(unsigned int irq, const struct cpumask *mask) 114 { 115 int i = 0, old_cpu, cpu, int_on, k; 116 u64 cur_ints; 117 unsigned long flags; 118 unsigned int irq_dirty; 119 120 if (cpumask_weight(mask) != 1) { 121 printk("attempted to set irq affinity for irq %d to multiple CPUs\n", irq); 122 return -1; 123 } 124 i = cpumask_first(mask); 125 126 /* Convert logical CPU to physical CPU */ 127 cpu = cpu_logical_map(i); 128 129 /* Protect against other affinity changers and IMR manipulation */ 130 spin_lock_irqsave(&bcm1480_imr_lock, flags); 131 132 /* Swizzle each CPU's IMR (but leave the IP selection alone) */ 133 old_cpu = bcm1480_irq_owner[irq]; 134 irq_dirty = irq; 135 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) { 136 irq_dirty -= BCM1480_NR_IRQS_HALF; 137 } 138 139 for (k=0; k<2; k++) { /* Loop through high and low interrupt mask register */ 140 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 141 int_on = !(cur_ints & (((u64) 1) << irq_dirty)); 142 if (int_on) { 143 /* If it was on, mask it */ 144 cur_ints |= (((u64) 1) << irq_dirty); 145 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 146 } 147 bcm1480_irq_owner[irq] = cpu; 148 if (int_on) { 149 /* unmask for the new CPU */ 150 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 151 cur_ints &= ~(((u64) 1) << irq_dirty); 152 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 153 } 154 } 155 spin_unlock_irqrestore(&bcm1480_imr_lock, flags); 156 157 return 0; 158 } 159 #endif 160 161 162 /*****************************************************************************/ 163 164 static void disable_bcm1480_irq(unsigned int irq) 165 { 166 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq); 167 } 168 169 static void enable_bcm1480_irq(unsigned int irq) 170 { 171 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq); 172 } 173 174 175 static void ack_bcm1480_irq(unsigned int irq) 176 { 177 u64 pending; 178 unsigned int irq_dirty; 179 int k; 180 181 /* 182 * If the interrupt was an HT interrupt, now is the time to 183 * clear it. NOTE: we assume the HT bridge was set up to 184 * deliver the interrupts to all CPUs (which makes affinity 185 * changing easier for us) 186 */ 187 irq_dirty = irq; 188 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) { 189 irq_dirty -= BCM1480_NR_IRQS_HALF; 190 } 191 for (k=0; k<2; k++) { /* Loop through high and low LDT interrupts */ 192 pending = __raw_readq(IOADDR(A_BCM1480_IMR_REGISTER(bcm1480_irq_owner[irq], 193 R_BCM1480_IMR_LDT_INTERRUPT_H + (k*BCM1480_IMR_HL_SPACING)))); 194 pending &= ((u64)1 << (irq_dirty)); 195 if (pending) { 196 #ifdef CONFIG_SMP 197 int i; 198 for (i=0; i<NR_CPUS; i++) { 199 /* 200 * Clear for all CPUs so an affinity switch 201 * doesn't find an old status 202 */ 203 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(cpu_logical_map(i), 204 R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING)))); 205 } 206 #else 207 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING)))); 208 #endif 209 210 /* 211 * Generate EOI. For Pass 1 parts, EOI is a nop. For 212 * Pass 2, the LDT world may be edge-triggered, but 213 * this EOI shouldn't hurt. If they are 214 * level-sensitive, the EOI is required. 215 */ 216 #ifdef CONFIG_PCI 217 if (ht_eoi_space) 218 *(uint32_t *)(ht_eoi_space+(irq<<16)+(7<<2)) = 0; 219 #endif 220 } 221 } 222 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq); 223 } 224 225 226 static void end_bcm1480_irq(unsigned int irq) 227 { 228 if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) { 229 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq); 230 } 231 } 232 233 234 void __init init_bcm1480_irqs(void) 235 { 236 int i; 237 238 for (i = 0; i < BCM1480_NR_IRQS; i++) { 239 set_irq_chip_and_handler(i, &bcm1480_irq_type, handle_level_irq); 240 bcm1480_irq_owner[i] = 0; 241 } 242 } 243 244 /* 245 * init_IRQ is called early in the boot sequence from init/main.c. It 246 * is responsible for setting up the interrupt mapper and installing the 247 * handler that will be responsible for dispatching interrupts to the 248 * "right" place. 249 */ 250 /* 251 * For now, map all interrupts to IP[2]. We could save 252 * some cycles by parceling out system interrupts to different 253 * IP lines, but keep it simple for bringup. We'll also direct 254 * all interrupts to a single CPU; we should probably route 255 * PCI and LDT to one cpu and everything else to the other 256 * to balance the load a bit. 257 * 258 * On the second cpu, everything is set to IP5, which is 259 * ignored, EXCEPT the mailbox interrupt. That one is 260 * set to IP[2] so it is handled. This is needed so we 261 * can do cross-cpu function calls, as requred by SMP 262 */ 263 264 #define IMR_IP2_VAL K_BCM1480_INT_MAP_I0 265 #define IMR_IP3_VAL K_BCM1480_INT_MAP_I1 266 #define IMR_IP4_VAL K_BCM1480_INT_MAP_I2 267 #define IMR_IP5_VAL K_BCM1480_INT_MAP_I3 268 #define IMR_IP6_VAL K_BCM1480_INT_MAP_I4 269 270 void __init arch_init_irq(void) 271 { 272 unsigned int i, cpu; 273 u64 tmp; 274 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 | 275 STATUSF_IP1 | STATUSF_IP0; 276 277 /* Default everything to IP2 */ 278 /* Start with _high registers which has no bit 0 interrupt source */ 279 for (i = 1; i < BCM1480_NR_IRQS_HALF; i++) { /* was I0 */ 280 for (cpu = 0; cpu < 4; cpu++) { 281 __raw_writeq(IMR_IP2_VAL, 282 IOADDR(A_BCM1480_IMR_REGISTER(cpu, 283 R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (i << 3))); 284 } 285 } 286 287 /* Now do _low registers */ 288 for (i = 0; i < BCM1480_NR_IRQS_HALF; i++) { 289 for (cpu = 0; cpu < 4; cpu++) { 290 __raw_writeq(IMR_IP2_VAL, 291 IOADDR(A_BCM1480_IMR_REGISTER(cpu, 292 R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) + (i << 3))); 293 } 294 } 295 296 init_bcm1480_irqs(); 297 298 /* 299 * Map the high 16 bits of mailbox_0 registers to IP[3], for 300 * inter-cpu messages 301 */ 302 /* Was I1 */ 303 for (cpu = 0; cpu < 4; cpu++) { 304 __raw_writeq(IMR_IP3_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + 305 (K_BCM1480_INT_MBOX_0_0 << 3))); 306 } 307 308 309 /* Clear the mailboxes. The firmware may leave them dirty */ 310 for (cpu = 0; cpu < 4; cpu++) { 311 __raw_writeq(0xffffffffffffffffULL, 312 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_0_CLR_CPU))); 313 __raw_writeq(0xffffffffffffffffULL, 314 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_1_CLR_CPU))); 315 } 316 317 318 /* Mask everything except the high 16 bit of mailbox_0 registers for all cpus */ 319 tmp = ~((u64) 0) ^ ( (((u64) 1) << K_BCM1480_INT_MBOX_0_0)); 320 for (cpu = 0; cpu < 4; cpu++) { 321 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_H))); 322 } 323 tmp = ~((u64) 0); 324 for (cpu = 0; cpu < 4; cpu++) { 325 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_L))); 326 } 327 328 /* 329 * Note that the timer interrupts are also mapped, but this is 330 * done in bcm1480_time_init(). Also, the profiling driver 331 * does its own management of IP7. 332 */ 333 334 /* Enable necessary IPs, disable the rest */ 335 change_c0_status(ST0_IM, imask); 336 } 337 338 extern void bcm1480_mailbox_interrupt(void); 339 340 static inline void dispatch_ip2(void) 341 { 342 unsigned long long mask_h, mask_l; 343 unsigned int cpu = smp_processor_id(); 344 unsigned long base; 345 346 /* 347 * Default...we've hit an IP[2] interrupt, which means we've got to 348 * check the 1480 interrupt registers to figure out what to do. Need 349 * to detect which CPU we're on, now that smp_affinity is supported. 350 */ 351 base = A_BCM1480_IMR_MAPPER(cpu); 352 mask_h = __raw_readq( 353 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H)); 354 mask_l = __raw_readq( 355 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L)); 356 357 if (mask_h) { 358 if (mask_h ^ 1) 359 do_IRQ(fls64(mask_h) - 1); 360 else if (mask_l) 361 do_IRQ(63 + fls64(mask_l)); 362 } 363 } 364 365 asmlinkage void plat_irq_dispatch(void) 366 { 367 unsigned int cpu = smp_processor_id(); 368 unsigned int pending; 369 370 #ifdef CONFIG_SIBYTE_BCM1480_PROF 371 /* Set compare to count to silence count/compare timer interrupts */ 372 write_c0_compare(read_c0_count()); 373 #endif 374 375 pending = read_c0_cause() & read_c0_status(); 376 377 #ifdef CONFIG_SIBYTE_BCM1480_PROF 378 if (pending & CAUSEF_IP7) /* Cpu performance counter interrupt */ 379 sbprof_cpu_intr(); 380 else 381 #endif 382 383 if (pending & CAUSEF_IP4) 384 do_IRQ(K_BCM1480_INT_TIMER_0 + cpu); 385 #ifdef CONFIG_SMP 386 else if (pending & CAUSEF_IP3) 387 bcm1480_mailbox_interrupt(); 388 #endif 389 390 else if (pending & CAUSEF_IP2) 391 dispatch_ip2(); 392 } 393