1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2000,2001,2002,2003,2004 Broadcom Corporation 4 */ 5 #include <linux/kernel.h> 6 #include <linux/init.h> 7 #include <linux/linkage.h> 8 #include <linux/interrupt.h> 9 #include <linux/smp.h> 10 #include <linux/spinlock.h> 11 #include <linux/mm.h> 12 #include <linux/kernel_stat.h> 13 14 #include <asm/errno.h> 15 #include <asm/irq_regs.h> 16 #include <asm/signal.h> 17 #include <asm/io.h> 18 19 #include <asm/sibyte/bcm1480_regs.h> 20 #include <asm/sibyte/bcm1480_int.h> 21 #include <asm/sibyte/bcm1480_scd.h> 22 23 #include <asm/sibyte/sb1250_uart.h> 24 #include <asm/sibyte/sb1250.h> 25 26 /* 27 * These are the routines that handle all the low level interrupt stuff. 28 * Actions handled here are: initialization of the interrupt map, requesting of 29 * interrupt lines by handlers, dispatching if interrupts to handlers, probing 30 * for interrupt lines 31 */ 32 33 #ifdef CONFIG_PCI 34 extern unsigned long ht_eoi_space; 35 #endif 36 37 /* Store the CPU id (not the logical number) */ 38 int bcm1480_irq_owner[BCM1480_NR_IRQS]; 39 40 static DEFINE_RAW_SPINLOCK(bcm1480_imr_lock); 41 42 void bcm1480_mask_irq(int cpu, int irq) 43 { 44 unsigned long flags, hl_spacing; 45 u64 cur_ints; 46 47 raw_spin_lock_irqsave(&bcm1480_imr_lock, flags); 48 hl_spacing = 0; 49 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) { 50 hl_spacing = BCM1480_IMR_HL_SPACING; 51 irq -= BCM1480_NR_IRQS_HALF; 52 } 53 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 54 cur_ints |= (((u64) 1) << irq); 55 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 56 raw_spin_unlock_irqrestore(&bcm1480_imr_lock, flags); 57 } 58 59 void bcm1480_unmask_irq(int cpu, int irq) 60 { 61 unsigned long flags, hl_spacing; 62 u64 cur_ints; 63 64 raw_spin_lock_irqsave(&bcm1480_imr_lock, flags); 65 hl_spacing = 0; 66 if ((irq >= BCM1480_NR_IRQS_HALF) && (irq <= BCM1480_NR_IRQS)) { 67 hl_spacing = BCM1480_IMR_HL_SPACING; 68 irq -= BCM1480_NR_IRQS_HALF; 69 } 70 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 71 cur_ints &= ~(((u64) 1) << irq); 72 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + hl_spacing)); 73 raw_spin_unlock_irqrestore(&bcm1480_imr_lock, flags); 74 } 75 76 #ifdef CONFIG_SMP 77 static int bcm1480_set_affinity(struct irq_data *d, const struct cpumask *mask, 78 bool force) 79 { 80 unsigned int irq_dirty, irq = d->irq; 81 int i = 0, old_cpu, cpu, int_on, k; 82 u64 cur_ints; 83 unsigned long flags; 84 85 i = cpumask_first_and(mask, cpu_online_mask); 86 87 /* Convert logical CPU to physical CPU */ 88 cpu = cpu_logical_map(i); 89 90 /* Protect against other affinity changers and IMR manipulation */ 91 raw_spin_lock_irqsave(&bcm1480_imr_lock, flags); 92 93 /* Swizzle each CPU's IMR (but leave the IP selection alone) */ 94 old_cpu = bcm1480_irq_owner[irq]; 95 irq_dirty = irq; 96 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) { 97 irq_dirty -= BCM1480_NR_IRQS_HALF; 98 } 99 100 for (k=0; k<2; k++) { /* Loop through high and low interrupt mask register */ 101 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 102 int_on = !(cur_ints & (((u64) 1) << irq_dirty)); 103 if (int_on) { 104 /* If it was on, mask it */ 105 cur_ints |= (((u64) 1) << irq_dirty); 106 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(old_cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 107 } 108 bcm1480_irq_owner[irq] = cpu; 109 if (int_on) { 110 /* unmask for the new CPU */ 111 cur_ints = ____raw_readq(IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 112 cur_ints &= ~(((u64) 1) << irq_dirty); 113 ____raw_writeq(cur_ints, IOADDR(A_BCM1480_IMR_MAPPER(cpu) + R_BCM1480_IMR_INTERRUPT_MASK_H + (k*BCM1480_IMR_HL_SPACING))); 114 } 115 } 116 raw_spin_unlock_irqrestore(&bcm1480_imr_lock, flags); 117 118 return 0; 119 } 120 #endif 121 122 123 /*****************************************************************************/ 124 125 static void disable_bcm1480_irq(struct irq_data *d) 126 { 127 unsigned int irq = d->irq; 128 129 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq); 130 } 131 132 static void enable_bcm1480_irq(struct irq_data *d) 133 { 134 unsigned int irq = d->irq; 135 136 bcm1480_unmask_irq(bcm1480_irq_owner[irq], irq); 137 } 138 139 140 static void ack_bcm1480_irq(struct irq_data *d) 141 { 142 unsigned int irq_dirty, irq = d->irq; 143 u64 pending; 144 int k; 145 146 /* 147 * If the interrupt was an HT interrupt, now is the time to 148 * clear it. NOTE: we assume the HT bridge was set up to 149 * deliver the interrupts to all CPUs (which makes affinity 150 * changing easier for us) 151 */ 152 irq_dirty = irq; 153 if ((irq_dirty >= BCM1480_NR_IRQS_HALF) && (irq_dirty <= BCM1480_NR_IRQS)) { 154 irq_dirty -= BCM1480_NR_IRQS_HALF; 155 } 156 for (k=0; k<2; k++) { /* Loop through high and low LDT interrupts */ 157 pending = __raw_readq(IOADDR(A_BCM1480_IMR_REGISTER(bcm1480_irq_owner[irq], 158 R_BCM1480_IMR_LDT_INTERRUPT_H + (k*BCM1480_IMR_HL_SPACING)))); 159 pending &= ((u64)1 << (irq_dirty)); 160 if (pending) { 161 #ifdef CONFIG_SMP 162 int i; 163 for (i=0; i<NR_CPUS; i++) { 164 /* 165 * Clear for all CPUs so an affinity switch 166 * doesn't find an old status 167 */ 168 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(cpu_logical_map(i), 169 R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING)))); 170 } 171 #else 172 __raw_writeq(pending, IOADDR(A_BCM1480_IMR_REGISTER(0, R_BCM1480_IMR_LDT_INTERRUPT_CLR_H + (k*BCM1480_IMR_HL_SPACING)))); 173 #endif 174 175 /* 176 * Generate EOI. For Pass 1 parts, EOI is a nop. For 177 * Pass 2, the LDT world may be edge-triggered, but 178 * this EOI shouldn't hurt. If they are 179 * level-sensitive, the EOI is required. 180 */ 181 #ifdef CONFIG_PCI 182 if (ht_eoi_space) 183 *(uint32_t *)(ht_eoi_space+(irq<<16)+(7<<2)) = 0; 184 #endif 185 } 186 } 187 bcm1480_mask_irq(bcm1480_irq_owner[irq], irq); 188 } 189 190 static struct irq_chip bcm1480_irq_type = { 191 .name = "BCM1480-IMR", 192 .irq_mask_ack = ack_bcm1480_irq, 193 .irq_mask = disable_bcm1480_irq, 194 .irq_unmask = enable_bcm1480_irq, 195 #ifdef CONFIG_SMP 196 .irq_set_affinity = bcm1480_set_affinity 197 #endif 198 }; 199 200 void __init init_bcm1480_irqs(void) 201 { 202 int i; 203 204 for (i = 0; i < BCM1480_NR_IRQS; i++) { 205 irq_set_chip_and_handler(i, &bcm1480_irq_type, 206 handle_level_irq); 207 bcm1480_irq_owner[i] = 0; 208 } 209 } 210 211 /* 212 * init_IRQ is called early in the boot sequence from init/main.c. It 213 * is responsible for setting up the interrupt mapper and installing the 214 * handler that will be responsible for dispatching interrupts to the 215 * "right" place. 216 */ 217 /* 218 * For now, map all interrupts to IP[2]. We could save 219 * some cycles by parceling out system interrupts to different 220 * IP lines, but keep it simple for bringup. We'll also direct 221 * all interrupts to a single CPU; we should probably route 222 * PCI and LDT to one cpu and everything else to the other 223 * to balance the load a bit. 224 * 225 * On the second cpu, everything is set to IP5, which is 226 * ignored, EXCEPT the mailbox interrupt. That one is 227 * set to IP[2] so it is handled. This is needed so we 228 * can do cross-cpu function calls, as required by SMP 229 */ 230 231 #define IMR_IP2_VAL K_BCM1480_INT_MAP_I0 232 #define IMR_IP3_VAL K_BCM1480_INT_MAP_I1 233 #define IMR_IP4_VAL K_BCM1480_INT_MAP_I2 234 #define IMR_IP5_VAL K_BCM1480_INT_MAP_I3 235 #define IMR_IP6_VAL K_BCM1480_INT_MAP_I4 236 237 void __init arch_init_irq(void) 238 { 239 unsigned int i, cpu; 240 u64 tmp; 241 unsigned int imask = STATUSF_IP4 | STATUSF_IP3 | STATUSF_IP2 | 242 STATUSF_IP1 | STATUSF_IP0; 243 244 /* Default everything to IP2 */ 245 /* Start with _high registers which has no bit 0 interrupt source */ 246 for (i = 1; i < BCM1480_NR_IRQS_HALF; i++) { /* was I0 */ 247 for (cpu = 0; cpu < 4; cpu++) { 248 __raw_writeq(IMR_IP2_VAL, 249 IOADDR(A_BCM1480_IMR_REGISTER(cpu, 250 R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + (i << 3))); 251 } 252 } 253 254 /* Now do _low registers */ 255 for (i = 0; i < BCM1480_NR_IRQS_HALF; i++) { 256 for (cpu = 0; cpu < 4; cpu++) { 257 __raw_writeq(IMR_IP2_VAL, 258 IOADDR(A_BCM1480_IMR_REGISTER(cpu, 259 R_BCM1480_IMR_INTERRUPT_MAP_BASE_L) + (i << 3))); 260 } 261 } 262 263 init_bcm1480_irqs(); 264 265 /* 266 * Map the high 16 bits of mailbox_0 registers to IP[3], for 267 * inter-cpu messages 268 */ 269 /* Was I1 */ 270 for (cpu = 0; cpu < 4; cpu++) { 271 __raw_writeq(IMR_IP3_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H) + 272 (K_BCM1480_INT_MBOX_0_0 << 3))); 273 } 274 275 276 /* Clear the mailboxes. The firmware may leave them dirty */ 277 for (cpu = 0; cpu < 4; cpu++) { 278 __raw_writeq(0xffffffffffffffffULL, 279 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_0_CLR_CPU))); 280 __raw_writeq(0xffffffffffffffffULL, 281 IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_MAILBOX_1_CLR_CPU))); 282 } 283 284 285 /* Mask everything except the high 16 bit of mailbox_0 registers for all cpus */ 286 tmp = ~((u64) 0) ^ ( (((u64) 1) << K_BCM1480_INT_MBOX_0_0)); 287 for (cpu = 0; cpu < 4; cpu++) { 288 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_H))); 289 } 290 tmp = ~((u64) 0); 291 for (cpu = 0; cpu < 4; cpu++) { 292 __raw_writeq(tmp, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MASK_L))); 293 } 294 295 /* 296 * Note that the timer interrupts are also mapped, but this is 297 * done in bcm1480_time_init(). Also, the profiling driver 298 * does its own management of IP7. 299 */ 300 301 /* Enable necessary IPs, disable the rest */ 302 change_c0_status(ST0_IM, imask); 303 } 304 305 extern void bcm1480_mailbox_interrupt(void); 306 307 static inline void dispatch_ip2(void) 308 { 309 unsigned long long mask_h, mask_l; 310 unsigned int cpu = smp_processor_id(); 311 unsigned long base; 312 313 /* 314 * Default...we've hit an IP[2] interrupt, which means we've got to 315 * check the 1480 interrupt registers to figure out what to do. Need 316 * to detect which CPU we're on, now that smp_affinity is supported. 317 */ 318 base = A_BCM1480_IMR_MAPPER(cpu); 319 mask_h = __raw_readq( 320 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_H)); 321 mask_l = __raw_readq( 322 IOADDR(base + R_BCM1480_IMR_INTERRUPT_STATUS_BASE_L)); 323 324 if (mask_h) { 325 if (mask_h ^ 1) 326 do_IRQ(fls64(mask_h) - 1); 327 else if (mask_l) 328 do_IRQ(63 + fls64(mask_l)); 329 } 330 } 331 332 asmlinkage void plat_irq_dispatch(void) 333 { 334 unsigned int cpu = smp_processor_id(); 335 unsigned int pending; 336 337 pending = read_c0_cause() & read_c0_status(); 338 339 if (pending & CAUSEF_IP4) 340 do_IRQ(K_BCM1480_INT_TIMER_0 + cpu); 341 #ifdef CONFIG_SMP 342 else if (pending & CAUSEF_IP3) 343 bcm1480_mailbox_interrupt(); 344 #endif 345 346 else if (pending & CAUSEF_IP2) 347 dispatch_ip2(); 348 } 349