err.no Git - linux-2.6/blob - arch/powerpc/platforms/cell/interrupt.c

   1 /*
   2  * Cell Internal Interrupt Controller
   3  *
   4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
   5  *
   6  * Author: Arnd Bergmann <arndb@de.ibm.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2, or (at your option)
  11  * any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23 #include <linux/config.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/irq.h>
  26 #include <linux/module.h>
  27 #include <linux/percpu.h>
  28 #include <linux/types.h>
  29
  30 #include <asm/io.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/prom.h>
  33 #include <asm/ptrace.h>
  34
  35 #include "interrupt.h"
  36
  37 struct iic_pending_bits {
  38         u32 data;
  39         u8 flags;
  40         u8 class;
  41         u8 source;
  42         u8 prio;
  43 };
  44
  45 enum iic_pending_flags {
  46         IIC_VALID = 0x80,
  47         IIC_IPI   = 0x40,
  48 };
  49
  50 struct iic_regs {
  51         struct iic_pending_bits pending;
  52         struct iic_pending_bits pending_destr;
  53         u64 generate;
  54         u64 prio;
  55 };
  56
  57 struct iic {
  58         struct iic_regs __iomem *regs;
  59         u8 target_id;
  60 };
  61
  62 static DEFINE_PER_CPU(struct iic, iic);
  63
  64 void iic_local_enable(void)
  65 {
  66         out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
  67 }
  68
  69 void iic_local_disable(void)
  70 {
  71         out_be64(&__get_cpu_var(iic).regs->prio, 0x0);
  72 }
  73
  74 static unsigned int iic_startup(unsigned int irq)
  75 {
  76         return 0;
  77 }
  78
  79 static void iic_enable(unsigned int irq)
  80 {
  81         iic_local_enable();
  82 }
  83
  84 static void iic_disable(unsigned int irq)
  85 {
  86 }
  87
  88 static void iic_end(unsigned int irq)
  89 {
  90         iic_local_enable();
  91 }
  92
  93 static struct hw_interrupt_type iic_pic = {
  94         .typename = " CELL-IIC ",
  95         .startup = iic_startup,
  96         .enable = iic_enable,
  97         .disable = iic_disable,
  98         .end = iic_end,
  99 };
 100
 101 static int iic_external_get_irq(struct iic_pending_bits pending)
 102 {
 103         int irq;
 104         unsigned char node, unit;
 105
 106         node = pending.source >> 4;
 107         unit = pending.source & 0xf;
 108         irq = -1;
 109
 110         /*
 111          * This mapping is specific to the Cell Broadband
 112          * Engine. We might need to get the numbers
 113          * from the device tree to support future CPUs.
 114          */
 115         switch (unit) {
 116         case 0x00:
 117         case 0x0b:
 118                 /*
 119                  * One of these units can be connected
 120                  * to an external interrupt controller.
 121                  */
 122                 if (pending.prio > 0x3f ||
 123                     pending.class != 2)
 124                         break;
 125                 irq = IIC_EXT_OFFSET
 126                         + spider_get_irq(node)
 127                         + node * IIC_NODE_STRIDE;
 128                 break;
 129         case 0x01 ... 0x04:
 130         case 0x07 ... 0x0a:
 131                 /*
 132                  * These units are connected to the SPEs
 133                  */
 134                 if (pending.class > 2)
 135                         break;
 136                 irq = IIC_SPE_OFFSET
 137                         + pending.class * IIC_CLASS_STRIDE
 138                         + node * IIC_NODE_STRIDE
 139                         + unit;
 140                 break;
 141         }
 142         if (irq == -1)
 143                 printk(KERN_WARNING "Unexpected interrupt class %02x, "
 144                         "source %02x, prio %02x, cpu %02x\n", pending.class,
 145                         pending.source, pending.prio, smp_processor_id());
 146         return irq;
 147 }
 148
 149 /* Get an IRQ number from the pending state register of the IIC */
 150 int iic_get_irq(struct pt_regs *regs)
 151 {
 152         struct iic *iic;
 153         int irq;
 154         struct iic_pending_bits pending;
 155
 156         iic = &__get_cpu_var(iic);
 157         *(unsigned long *) &pending =
 158                 in_be64((unsigned long __iomem *) &iic->regs->pending_destr);
 159
 160         irq = -1;
 161         if (pending.flags & IIC_VALID) {
 162                 if (pending.flags & IIC_IPI) {
 163                         irq = IIC_IPI_OFFSET + (pending.prio >> 4);
 164 /*
 165                         if (irq > 0x80)
 166                                 printk(KERN_WARNING "Unexpected IPI prio %02x"
 167                                         "on CPU %02x\n", pending.prio,
 168                                                         smp_processor_id());
 169 */
 170                 } else {
 171                         irq = iic_external_get_irq(pending);
 172                 }
 173         }
 174         return irq;
 175 }
 176
 177 /* hardcoded part to be compatible with older firmware */
 178
 179 static int setup_iic_hardcoded(void)
 180 {
 181         struct device_node *np;
 182         int nodeid, cpu;
 183         unsigned long regs;
 184         struct iic *iic;
 185
 186         for_each_cpu(cpu) {
 187                 iic = &per_cpu(iic, cpu);
 188                 nodeid = cpu/2;
 189
 190                 for (np = of_find_node_by_type(NULL, "cpu");
 191                      np;
 192                      np = of_find_node_by_type(np, "cpu")) {
 193                         if (nodeid == *(int *)get_property(np, "node-id", NULL))
 194                                 break;
 195                         }
 196
 197                 if (!np) {
 198                         printk(KERN_WARNING "IIC: CPU %d not found\n", cpu);
 199                         iic->regs = NULL;
 200                         iic->target_id = 0xff;
 201                         return -ENODEV;
 202                         }
 203
 204                 regs = *(long *)get_property(np, "iic", NULL);
 205
 206                 /* hack until we have decided on the devtree info */
 207                 regs += 0x400;
 208                 if (cpu & 1)
 209                         regs += 0x20;
 210
 211                 printk(KERN_INFO "IIC for CPU %d at %lx\n", cpu, regs);
 212                 iic->regs = __ioremap(regs, sizeof(struct iic_regs),
 213                                       _PAGE_NO_CACHE);
 214
 215                 iic->target_id = (nodeid << 4) + ((cpu & 1) ? 0xf : 0xe);
 216         }
 217
 218         return 0;
 219 }
 220
 221 static int setup_iic(void)
 222 {
 223         struct device_node *dn;
 224         unsigned long *regs;
 225         char *compatible;
 226         unsigned *np, found = 0;
 227         struct iic *iic = NULL;
 228
 229         for (dn = NULL; (dn = of_find_node_by_name(dn, "interrupt-controller"));) {
 230                 compatible = (char *)get_property(dn, "compatible", NULL);
 231
 232                 if (!compatible) {
 233                         printk(KERN_WARNING "no compatible property found !\n");
 234                         continue;
 235                 }
 236
 237                 if (strstr(compatible, "IBM,CBEA-Internal-Interrupt-Controller"))
 238                         regs = (unsigned long *)get_property(dn,"reg", NULL);
 239                 else
 240                         continue;
 241
 242                 if (!regs)
 243                         printk(KERN_WARNING "IIC: no reg property\n");
 244
 245                 np = (unsigned int *)get_property(dn, "ibm,interrupt-server-ranges", NULL);
 246
 247                 if (!np) {
 248                         printk(KERN_WARNING "IIC: CPU association not found\n");
 249                         iic->regs = NULL;
 250                         iic->target_id = 0xff;
 251                         return -ENODEV;
 252                 }
 253
 254                 iic = &per_cpu(iic, np[0]);
 255                 iic->regs = __ioremap(regs[0], sizeof(struct iic_regs),
 256                                       _PAGE_NO_CACHE);
 257                 iic->target_id = ((np[0] & 2) << 3) + ((np[0] & 1) ? 0xf : 0xe);
 258                 printk("IIC for CPU %d at %lx mapped to %p\n", np[0], regs[0], iic->regs);
 259
 260                 iic = &per_cpu(iic, np[1]);
 261                 iic->regs = __ioremap(regs[2], sizeof(struct iic_regs),
 262                                       _PAGE_NO_CACHE);
 263                 iic->target_id = ((np[1] & 2) << 3) + ((np[1] & 1) ? 0xf : 0xe);
 264                 printk("IIC for CPU %d at %lx mapped to %p\n", np[1], regs[2], iic->regs);
 265
 266                 found++;
 267         }
 268
 269         if (found)
 270                 return 0;
 271         else
 272                 return -ENODEV;
 273 }
 274
 275 #ifdef CONFIG_SMP
 276
 277 /* Use the highest interrupt priorities for IPI */
 278 static inline int iic_ipi_to_irq(int ipi)
 279 {
 280         return IIC_IPI_OFFSET + IIC_NUM_IPIS - 1 - ipi;
 281 }
 282
 283 static inline int iic_irq_to_ipi(int irq)
 284 {
 285         return IIC_NUM_IPIS - 1 - (irq - IIC_IPI_OFFSET);
 286 }
 287
 288 void iic_setup_cpu(void)
 289 {
 290         out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
 291 }
 292
 293 void iic_cause_IPI(int cpu, int mesg)
 294 {
 295         out_be64(&per_cpu(iic, cpu).regs->generate, (IIC_NUM_IPIS - 1 - mesg) << 4);
 296 }
 297
 298 u8 iic_get_target_id(int cpu)
 299 {
 300         return per_cpu(iic, cpu).target_id;
 301 }
 302 EXPORT_SYMBOL_GPL(iic_get_target_id);
 303
 304 static irqreturn_t iic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
 305 {
 306         smp_message_recv(iic_irq_to_ipi(irq), regs);
 307         return IRQ_HANDLED;
 308 }
 309
 310 static void iic_request_ipi(int ipi, const char *name)
 311 {
 312         int irq;
 313
 314         irq = iic_ipi_to_irq(ipi);
 315         /* IPIs are marked SA_INTERRUPT as they must run with irqs
 316          * disabled */
 317         get_irq_desc(irq)->handler = &iic_pic;
 318         get_irq_desc(irq)->status |= IRQ_PER_CPU;
 319         request_irq(irq, iic_ipi_action, SA_INTERRUPT, name, NULL);
 320 }
 321
 322 void iic_request_IPIs(void)
 323 {
 324         iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
 325         iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
 326 #ifdef CONFIG_DEBUGGER
 327         iic_request_ipi(PPC_MSG_DEBUGGER_BREAK, "IPI-debug");
 328 #endif /* CONFIG_DEBUGGER */
 329 }
 330 #endif /* CONFIG_SMP */
 331
 332 static void iic_setup_spe_handlers(void)
 333 {
 334         int be, isrc;
 335
 336         /* Assume two threads per BE are present */
 337         for (be=0; be < num_present_cpus() / 2; be++) {
 338                 for (isrc = 0; isrc < IIC_CLASS_STRIDE * 3; isrc++) {
 339                         int irq = IIC_NODE_STRIDE * be + IIC_SPE_OFFSET + isrc;
 340                         get_irq_desc(irq)->handler = &iic_pic;
 341                 }
 342         }
 343 }
 344
 345 void iic_init_IRQ(void)
 346 {
 347         int cpu, irq_offset;
 348         struct iic *iic;
 349
 350         if (setup_iic() < 0)
 351                 setup_iic_hardcoded();
 352
 353         irq_offset = 0;
 354         for_each_cpu(cpu) {
 355                 iic = &per_cpu(iic, cpu);
 356                 if (iic->regs)
 357                         out_be64(&iic->regs->prio, 0xff);
 358         }
 359         iic_setup_spe_handlers();
 360 }