target/linux/brcm63xx/patches-2.6.25/060-bcm963xx_rewrite_irq_handling_code.patch

   1 From 9a70f2dcb24a5aab29386373c86ba035acba4891 Mon Sep 17 00:00:00 2001
   2 From: Axel Gembe <ago@bastart.eu.org>
   3 Date: Sun, 18 May 2008 12:07:21 +0200
   4 Subject: [PATCH] bcm963xx: rewrite irq handling code
   5
   6 This patch adds interrupt handling as on AR7. The old code was very messy and
   7 didn't work too well.
   8
   9 Signed-off-by: Axel Gembe <ago@bastart.eu.org>
  10 ---
  11  arch/mips/bcm963xx/irq.c                  |  308 ++++++++++-------------------
  12  drivers/serial/bcm63xx_cons.c             |   13 +-
  13  include/asm-mips/mach-bcm963xx/bcm_intr.h |   18 +--
  14  3 files changed, 119 insertions(+), 220 deletions(-)
  15
  16 Index: linux-2.6.25.4/arch/mips/bcm963xx/irq.c
  17 ===================================================================
  18 --- linux-2.6.25.4.orig/arch/mips/bcm963xx/irq.c
  19 +++ linux-2.6.25.4/arch/mips/bcm963xx/irq.c
  20 @@ -1,259 +1,159 @@
  21  /*
  22 -<:copyright-gpl
  23 - Copyright 2002 Broadcom Corp. All Rights Reserved.
  24 -
  25 - This program is free software; you can distribute it and/or modify it
  26 - under the terms of the GNU General Public License (Version 2) as
  27 - published by the Free Software Foundation.
  28 -
  29 - This program is distributed in the hope it will be useful, but WITHOUT
  30 - ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  31 - FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  32 - for more details.
  33 -
  34 - You should have received a copy of the GNU General Public License along
  35 - with this program; if not, write to the Free Software Foundation, Inc.,
  36 - 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  37 -:>
  38 -*/
  39 -/*
  40 - * Interrupt control functions for Broadcom 963xx MIPS boards
  41 + * Copyright (C) 2006,2007 Felix Fietkau <nbd@openwrt.org>
  42 + * Copyright (C) 2006,2007 Eugene Konev <ejka@openwrt.org>
  43 + * Copyright (C) 2008 Axel Gembe <ago@bastart.eu.org>
  44 + *
  45 + * This program is free software; you can redistribute it and/or modify
  46 + * it under the terms of the GNU General Public License as published by
  47 + * the Free Software Foundation; either version 2 of the License, or
  48 + * (at your option) any later version.
  49 + *
  50 + * This program is distributed in the hope that it will be useful,
  51 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  52 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  53 + * GNU General Public License for more details.
  54 + *
  55 + * You should have received a copy of the GNU General Public License
  56 + * along with this program; if not, write to the Free Software
  57 + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  58   */
  59
  60 -#include <asm/atomic.h>
  61 -
  62 -#include <linux/delay.h>
  63 -#include <linux/init.h>
  64 -#include <linux/ioport.h>
  65 -#include <linux/irq.h>
  66  #include <linux/interrupt.h>
  67 -#include <linux/kernel.h>
  68 -#include <linux/slab.h>
  69 -#include <linux/module.h>
  70 +#include <linux/io.h>
  71
  72 -#include <asm/irq.h>
  73 +#include <asm/irq_cpu.h>
  74  #include <asm/mipsregs.h>
  75 -#include <asm/addrspace.h>
  76 -#include <asm/signal.h>
  77 +
  78  #include <6348_map_part.h>
  79  #include <6348_intr.h>
  80  #include <bcm_map_part.h>
  81  #include <bcm_intr.h>
  82
  83 -static void irq_dispatch_int(void)
  84 -{
  85 -       unsigned int pendingIrqs;
  86 -       static unsigned int irqBit;
  87 -       static unsigned int isrNumber = 31;
  88 -
  89 -       pendingIrqs = PERF->IrqStatus & PERF->IrqMask;
  90 -       if (!pendingIrqs) {
  91 -               return;
  92 -       }
  93 +static int bcm963xx_irq_base;
  94
  95 -       while (1) {
  96 -       irqBit <<= 1;
  97 -       isrNumber++;
  98 -       if (isrNumber == 32) {
  99 -               isrNumber = 0;
 100 -               irqBit = 0x1;
 101 -       }
 102 -       if (pendingIrqs & irqBit) {
 103 -                       PERF->IrqMask &= ~irqBit; // mask
 104 -                       do_IRQ(isrNumber + INTERNAL_ISR_TABLE_OFFSET);
 105 -               break;
 106 -       }
 107 -       }
 108 +void bcm963xx_unmask_irq(unsigned int irq)
 109 +{
 110 +       PERF->IrqMask |= (1 << (irq - bcm963xx_irq_base));
 111  }
 112
 113 -static void irq_dispatch_ext(uint32 irq)
 114 +void bcm963xx_mask_irq(unsigned int irq)
 115  {
 116 -       if (!(PERF->ExtIrqCfg & (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT)))) {
 117 -       printk("**** Ext IRQ mask. Should not dispatch ****\n");
 118 -       }
 119 -       /* disable and clear interrupt in the controller */
 120 -       PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));
 121 -       PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));
 122 -       do_IRQ(irq);
 123 +       PERF->IrqMask &= ~(1 << (irq - bcm963xx_irq_base));
 124  }
 125
 126 -
 127 -//extern void brcm_timer_interrupt(struct pt_regs *regs);
 128 -
 129 -asmlinkage void plat_irq_dispatch(void)
 130 +void bcm963xx_ack_irq(unsigned int irq)
 131  {
 132 -       unsigned long cause;
 133 -
 134 -       cause = read_c0_status() & read_c0_cause() & ST0_IM;
 135 -       if (cause & CAUSEF_IP7)
 136 -               do_IRQ(7);
 137 -       else if (cause & CAUSEF_IP2)
 138 -               irq_dispatch_int();
 139 -       else if (cause & CAUSEF_IP3)
 140 -               irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_0);
 141 -       else if (cause & CAUSEF_IP4)
 142 -               irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_1);
 143 -       else if (cause & CAUSEF_IP5)
 144 -               irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_2);
 145 -       else if (cause & CAUSEF_IP6) {
 146 -               irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_3);
 147 -               local_irq_disable();
 148 -       }
 149 +       PERF->IrqStatus &= ~(1 << (irq - bcm963xx_irq_base));
 150  }
 151
 152 -
 153 -void enable_brcm_irq(unsigned int irq)
 154 +void bcm963xx_unmask_ext_irq(unsigned int irq)
 155  {
 156 -       unsigned long flags;
 157 -
 158 -       local_irq_save(flags);
 159 -       if( irq >= INTERNAL_ISR_TABLE_OFFSET ) {
 160 -       PERF->IrqMask |= (1 << (irq - INTERNAL_ISR_TABLE_OFFSET));
 161 -       }
 162 -       else if (irq >= INTERRUPT_ID_EXTERNAL_0 && irq <= INTERRUPT_ID_EXTERNAL_3) {
 163 -       /* enable and clear interrupt in the controller */
 164 -       PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));
 165         PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));
 166 -       }
 167 -       local_irq_restore(flags);
 168  }
 169
 170 -void disable_brcm_irq(unsigned int irq)
 171 +void bcm963xx_mask_ext_irq(unsigned int irq)
 172  {
 173 -       unsigned long flags;
 174 -
 175 -       local_irq_save(flags);
 176 -       if( irq >= INTERNAL_ISR_TABLE_OFFSET ) {
 177 -       PERF->IrqMask &= ~(1 << (irq - INTERNAL_ISR_TABLE_OFFSET));
 178 -       }
 179 -       else if (irq >= INTERRUPT_ID_EXTERNAL_0 && irq <= INTERRUPT_ID_EXTERNAL_3) {
 180 -       /* disable interrupt in the controller */
 181         PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));
 182 -       }
 183 -       local_irq_restore(flags);
 184  }
 185
 186 -void ack_brcm_irq(unsigned int irq)
 187 +void bcm963xx_ack_ext_irq(unsigned int irq)
 188  {
 189 -       /* Already done in brcm_irq_dispatch */
 190 +       PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));
 191  }
 192
 193 -unsigned int startup_brcm_irq(unsigned int irq)
 194 +static void bcm963xx_dispatch_ext_irq(unsigned int irq)
 195  {
 196 -       enable_brcm_irq(irq);
 197 -
 198 -       return 0; /* never anything pending */
 199 +       bcm963xx_ack_ext_irq(irq);
 200 +       bcm963xx_mask_ext_irq(irq);
 201 +       do_IRQ(irq);
 202  }
 203
 204 -unsigned int startup_brcm_none(unsigned int irq)
 205 +static void bcm963xx_cascade(void)
 206  {
 207 -       return 0;
 208 -}
 209 +       uint32_t pending, bit, irq;
 210
 211 -void end_brcm_irq(unsigned int irq)
 212 -{
 213 -       if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 214 -               enable_brcm_irq(irq);
 215 -}
 216 +       if (!(pending = PERF->IrqStatus & PERF->IrqMask))
 217 +               return;
 218
 219 -void end_brcm_none(unsigned int irq)
 220 -{
 221 -}
 222 +       for (irq = 0, bit = 1; irq < 32; irq++, bit <<= 1) {
 223 +               if (pending & bit) {
 224 +                       bcm963xx_ack_irq(irq + bcm963xx_irq_base);
 225 +                       bcm963xx_mask_irq(irq + bcm963xx_irq_base);
 226 +                       do_IRQ(irq + bcm963xx_irq_base);
 227 +                       return;
 228 +               }
 229 +       }
 230 +
 231 +       spurious_interrupt();
 232 +}
 233 +
 234 +static struct irq_chip bcm963xx_irq_type = {
 235 +       .name = "bcm963xx",
 236 +       .unmask = bcm963xx_unmask_irq,
 237 +       .mask = bcm963xx_mask_irq,
 238 +       .ack = bcm963xx_ack_irq
 239 +};
 240
 241 -static struct hw_interrupt_type brcm_irq_type = {
 242 -       .typename       = "MIPS",
 243 -       .startup        = startup_brcm_irq,
 244 -       .shutdown       = disable_brcm_irq,
 245 -       .enable = enable_brcm_irq,
 246 -       .disable        = disable_brcm_irq,
 247 -       .ack    = ack_brcm_irq,
 248 -       .end    = end_brcm_irq,
 249 -       .set_affinity = NULL
 250 +static struct irq_chip bcm963xx_ext_irq_type = {
 251 +       .name = "bcm963xx_ext",
 252 +       .unmask = bcm963xx_unmask_ext_irq,
 253 +       .mask = bcm963xx_mask_ext_irq,
 254 +       .ack = bcm963xx_ack_ext_irq,
 255  };
 256
 257 -static struct hw_interrupt_type brcm_irq_no_end_type = {
 258 -       .typename       = "MIPS",
 259 -       .startup        = startup_brcm_none,
 260 -       .shutdown       = disable_brcm_irq,
 261 -       .enable = enable_brcm_irq,
 262 -       .disable        = disable_brcm_irq,
 263 -       .ack    = ack_brcm_irq,
 264 -       .end    = end_brcm_none,
 265 -       .set_affinity = NULL
 266 +static struct irqaction bcm963xx_cascade_action = {
 267 +       .handler = no_action,
 268 +       .name = "BCM963xx cascade interrupt"
 269  };
 270
 271 -void __init arch_init_irq(void)
 272 +static void __init bcm963xx_irq_init(int base)
 273  {
 274         int i;
 275
 276 -       clear_c0_status(ST0_BEV);
 277 -       change_c0_status(ST0_IM, (IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | IE_IRQ3 | IE_IRQ4));
 278 +       bcm963xx_irq_base = base;
 279
 280 -       for (i = 0; i < NR_IRQS; i++) {
 281 -               irq_desc[i].status = IRQ_DISABLED;
 282 -               irq_desc[i].action = 0;
 283 -               irq_desc[i].depth = 1;
 284 -               irq_desc[i].chip = &brcm_irq_type;
 285 -       }
 286 +       /* External IRQs */
 287 +       set_irq_chip_and_handler(INTERRUPT_ID_EXTERNAL_0, &bcm963xx_ext_irq_type,
 288 +                                handle_level_irq);
 289 +       set_irq_chip_and_handler(INTERRUPT_ID_EXTERNAL_1, &bcm963xx_ext_irq_type,
 290 +                                handle_level_irq);
 291 +       set_irq_chip_and_handler(INTERRUPT_ID_EXTERNAL_2, &bcm963xx_ext_irq_type,
 292 +                                handle_level_irq);
 293 +       set_irq_chip_and_handler(INTERRUPT_ID_EXTERNAL_3, &bcm963xx_ext_irq_type,
 294 +                                handle_level_irq);
 295 +
 296 +       for (i = 0; i < 32; i++) {
 297 +               set_irq_chip_and_handler(base + i, &bcm963xx_irq_type,
 298 +                                        handle_level_irq);
 299 +       }
 300 +
 301 +       setup_irq(2, &bcm963xx_cascade_action);
 302 +       setup_irq(bcm963xx_irq_base, &bcm963xx_cascade_action);
 303 +       set_c0_status(IE_IRQ0);
 304  }
 305
 306 -int request_external_irq(unsigned int irq,
 307 -       FN_HANDLER handler,
 308 -               unsigned long irqflags,
 309 -               const char * devname,
 310 -               void *dev_id)
 311 +asmlinkage void plat_irq_dispatch(void)
 312  {
 313 -       unsigned long flags;
 314 -
 315 -       local_irq_save(flags);
 316 +       unsigned int pending = read_c0_status() & read_c0_cause() & ST0_IM;
 317
 318 -       PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));      // Clear
 319 -       PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));      // Mask
 320 -       PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_INSENS_SHFT));    // Edge insesnsitive
 321 -       PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_LEVEL_SHFT));      // Level triggered
 322 -       PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_SENSE_SHFT));     // Low level
 323 -
 324 -       local_irq_restore(flags);
 325 -
 326 -       return( request_irq(irq, handler, irqflags, devname, dev_id) );
 327 +       if (pending & STATUSF_IP7)              /* cpu timer */
 328 +               do_IRQ(7);
 329 +       else if (pending & STATUSF_IP2)         /* internal interrupt cascade */
 330 +               bcm963xx_cascade();
 331 +       else if (pending & STATUSF_IP3)
 332 +               bcm963xx_dispatch_ext_irq(INTERRUPT_ID_EXTERNAL_0);
 333 +       else if (pending & STATUSF_IP4)
 334 +               bcm963xx_dispatch_ext_irq(INTERRUPT_ID_EXTERNAL_1);
 335 +       else if (pending & STATUSF_IP5)
 336 +               bcm963xx_dispatch_ext_irq(INTERRUPT_ID_EXTERNAL_2);
 337 +       else if (pending & STATUSF_IP6)
 338 +               bcm963xx_dispatch_ext_irq(INTERRUPT_ID_EXTERNAL_3);
 339 +       else
 340 +               spurious_interrupt();
 341  }
 342
 343 -/* VxWorks compatibility function(s). */
 344 -
 345 -unsigned int BcmHalMapInterrupt(FN_HANDLER pfunc, unsigned int param,
 346 -       unsigned int interruptId)
 347 +void __init arch_init_irq(void)
 348  {
 349 -       int nRet = -1;
 350 -       char *devname;
 351 -
 352 -       devname = kmalloc(16, GFP_KERNEL);
 353 -       if (devname)
 354 -               sprintf( devname, "brcm_%d", interruptId );
 355 -
 356 -       /* Set the IRQ description to not automatically enable the interrupt at
 357 -        * the end of an ISR.  The driver that handles the interrupt must
 358 -        * explicitly call BcmHalInterruptEnable or enable_brcm_irq.  This behavior
 359 -        * is consistent with interrupt handling on VxWorks.
 360 -        */
 361 -       irq_desc[interruptId].chip = &brcm_irq_no_end_type;
 362 -
 363 -       if( interruptId >= INTERNAL_ISR_TABLE_OFFSET )
 364 -       {
 365 -               printk("BcmHalMapInterrupt : internal IRQ\n");
 366 -               nRet = request_irq( interruptId, pfunc, IRQF_DISABLED, devname, (void *) param );
 367 -       }
 368 -       else if (interruptId >= INTERRUPT_ID_EXTERNAL_0 && interruptId <= INTERRUPT_ID_EXTERNAL_3)
 369 -       {
 370 -               printk("BcmHalMapInterrupt : external IRQ\n");
 371 -               nRet = request_external_irq( interruptId, pfunc, IRQF_DISABLED, devname, (void *) param );
 372 -       }
 373 -
 374 -       return( nRet );
 375 +       mips_cpu_irq_init();
 376 +       bcm963xx_irq_init(INTERNAL_ISR_TABLE_OFFSET);
 377  }
 378 -
 379 -
 380 -EXPORT_SYMBOL(enable_brcm_irq);
 381 -EXPORT_SYMBOL(disable_brcm_irq);
 382 -EXPORT_SYMBOL(request_external_irq);
 383 -EXPORT_SYMBOL(BcmHalMapInterrupt);
 384 -
 385 Index: linux-2.6.25.4/drivers/serial/bcm63xx_cons.c
 386 ===================================================================
 387 --- linux-2.6.25.4.orig/drivers/serial/bcm63xx_cons.c
 388 +++ linux-2.6.25.4/drivers/serial/bcm63xx_cons.c
 389 @@ -267,7 +267,7 @@ static void bcm_interrupt(int irq, void
 390         }
 391
 392         // Clear the interrupt
 393 -       enable_brcm_irq(INTERRUPT_ID_UART);
 394 +//     bcm963xx_unmask_irq(INTERRUPT_ID_UART);
 395  #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
 396         return IRQ_HANDLED;
 397  #endif
 398 @@ -880,7 +880,7 @@ static int bcm63xx_cons_open(struct tty_
 399         info->count++;
 400         tty->driver_data = info;
 401         info->tty = tty;
 402 -       enable_brcm_irq(INTERRUPT_ID_UART);
 403 +       bcm963xx_unmask_irq(INTERRUPT_ID_UART);
 404
 405         // Start up serial port
 406         retval = startup(info);
 407 @@ -927,7 +927,7 @@ static struct tty_operations rs_ops = {
 408  -------------------------------------------------------------------------- */
 409  static int __init bcm63xx_serialinit(void)
 410  {
 411 -       int i, flags;
 412 +       int i, flags, res;
 413         struct bcm_serial *info;
 414
 415         // Print the driver version information
 416 @@ -981,7 +981,12 @@ static int __init bcm63xx_serialinit(voi
 417                  */
 418                 if (!info->port)
 419                         return 0;
 420 -               BcmHalMapInterrupt(bcm_interrupt, 0, INTERRUPT_ID_UART);
 421 +
 422 +               res = request_irq(INTERRUPT_ID_UART, bcm_interrupt, 0, "bcm-uart", NULL);
 423 +               if (res) {
 424 +                       spin_unlock_irqrestore(&bcm963xx_serial_lock, flags);
 425 +                       return res;
 426 +               }
 427         }
 428
 429         /* order matters here... the trick is that flags
 430 Index: linux-2.6.25.4/include/asm-mips/mach-bcm963xx/bcm_intr.h
 431 ===================================================================
 432 --- linux-2.6.25.4.orig/include/asm-mips/mach-bcm963xx/bcm_intr.h
 433 +++ linux-2.6.25.4/include/asm-mips/mach-bcm963xx/bcm_intr.h
 434 @@ -39,18 +39,12 @@ struct pt_regs;
 435  typedef int (*FN_HANDLER) (int, void *);
 436
 437  /* prototypes */
 438 -extern void enable_brcm_irq(unsigned int irq);
 439 -extern void disable_brcm_irq(unsigned int irq);
 440 -extern int request_external_irq(unsigned int irq,
 441 -    FN_HANDLER handler, unsigned long irqflags,
 442 -    const char * devname, void *dev_id);
 443 -extern unsigned int BcmHalMapInterrupt(FN_HANDLER isr, unsigned int param,
 444 -    unsigned int interruptId);
 445 -extern void dump_intr_regs(void);
 446 -
 447 -/* compatibility definitions */
 448 -#define BcmHalInterruptEnable(irq)      enable_brcm_irq( irq )
 449 -#define BcmHalInterruptDisable(irq)     disable_brcm_irq( irq )
 450 +extern void bcm963xx_unmask_irq(unsigned int irq);
 451 +extern void bcm963xx_mask_irq(unsigned int irq);
 452 +extern void bcm963xx_ack_irq(unsigned int irq);
 453 +extern void bcm963xx_unmask_ext_irq(unsigned int irq);
 454 +extern void bcm963xx_mask_ext_irq(unsigned int irq);
 455 +extern void bcm963xx_ack_ext_irq(unsigned int irq);
 456
 457  #ifdef __cplusplus
 458      }