target/linux/brcm63xx-2.6/files/arch/mips/bcm963xx/irq.c

   1 /*
   2 <:copyright-gpl
   3  Copyright 2002 Broadcom Corp. All Rights Reserved.
   4
   5  This program is free software; you can distribute it and/or modify it
   6  under the terms of the GNU General Public License (Version 2) as
   7  published by the Free Software Foundation.
   8
   9  This program is distributed in the hope it will be useful, but WITHOUT
  10  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  for more details.
  13
  14  You should have received a copy of the GNU General Public License along
  15  with this program; if not, write to the Free Software Foundation, Inc.,
  16  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  17 :>
  18 */
  19 /*
  20  * Interrupt control functions for Broadcom 963xx MIPS boards
  21  */
  22
  23 #include <asm/atomic.h>
  24
  25 #include <linux/delay.h>
  26 #include <linux/init.h>
  27 #include <linux/ioport.h>
  28 #include <linux/irq.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/kernel.h>
  31 #include <linux/slab.h>
  32 #include <linux/module.h>
  33
  34 #include <asm/irq.h>
  35 #include <asm/mipsregs.h>
  36 #include <asm/addrspace.h>
  37 #include <asm/signal.h>
  38 #include <bcm_map_part.h>
  39 #include <bcm_intr.h>
  40
  41 static void irq_dispatch_int(struct pt_regs *regs)
  42 {
  43         unsigned int pendingIrqs;
  44         static unsigned int irqBit;
  45         static unsigned int isrNumber = 31;
  46
  47         pendingIrqs = PERF->IrqStatus & PERF->IrqMask;
  48         if (!pendingIrqs) {
  49                 return;
  50         }
  51
  52         while (1) {
  53         irqBit <<= 1;
  54         isrNumber++;
  55         if (isrNumber == 32) {
  56                 isrNumber = 0;
  57                 irqBit = 0x1;
  58         }
  59         if (pendingIrqs & irqBit) {
  60                         PERF->IrqMask &= ~irqBit; // mask
  61                         do_IRQ(isrNumber + INTERNAL_ISR_TABLE_OFFSET);
  62                 break;
  63         }
  64         }
  65 }
  66
  67 static void irq_dispatch_ext(uint32 irq)
  68 {
  69         if (!(PERF->ExtIrqCfg & (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT)))) {
  70         printk("**** Ext IRQ mask. Should not dispatch ****\n");
  71         }
  72         /* disable and clear interrupt in the controller */
  73         PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));
  74         PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));
  75         do_IRQ(irq);
  76 }
  77
  78
  79 extern void brcm_timer_interrupt(struct pt_regs *regs);
  80
  81 asmlinkage void plat_irq_dispatch(struct pt_regs *regs)
  82 {
  83         u32 cause;
  84         while((cause = (read_c0_cause()& CAUSEF_IP))) {
  85                 if (cause & CAUSEF_IP7)
  86                         brcm_timer_interrupt(regs);
  87                 else if (cause & CAUSEF_IP2)
  88                         irq_dispatch_int(regs);
  89                 else if (cause & CAUSEF_IP3)
  90                         irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_0);
  91                 else if (cause & CAUSEF_IP4)
  92                         irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_1);
  93                 else if (cause & CAUSEF_IP5)
  94                         irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_2);
  95                 else if (cause & CAUSEF_IP6)
  96                         irq_dispatch_ext(INTERRUPT_ID_EXTERNAL_3);
  97                 local_irq_disable();
  98         }
  99 }
 100
 101
 102 void enable_brcm_irq(unsigned int irq)
 103 {
 104         unsigned long flags;
 105
 106         local_irq_save(flags);
 107         if( irq >= INTERNAL_ISR_TABLE_OFFSET ) {
 108         PERF->IrqMask |= (1 << (irq - INTERNAL_ISR_TABLE_OFFSET));
 109         }
 110         else if (irq >= INTERRUPT_ID_EXTERNAL_0 && irq <= INTERRUPT_ID_EXTERNAL_3) {
 111         /* enable and clear interrupt in the controller */
 112         PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));
 113         PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));
 114         }
 115         local_irq_restore(flags);
 116 }
 117
 118 void disable_brcm_irq(unsigned int irq)
 119 {
 120         unsigned long flags;
 121
 122         local_irq_save(flags);
 123         if( irq >= INTERNAL_ISR_TABLE_OFFSET ) {
 124         PERF->IrqMask &= ~(1 << (irq - INTERNAL_ISR_TABLE_OFFSET));
 125         }
 126         else if (irq >= INTERRUPT_ID_EXTERNAL_0 && irq <= INTERRUPT_ID_EXTERNAL_3) {
 127         /* disable interrupt in the controller */
 128         PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));
 129         }
 130         local_irq_restore(flags);
 131 }
 132
 133 void ack_brcm_irq(unsigned int irq)
 134 {
 135         /* Already done in brcm_irq_dispatch */
 136 }
 137
 138 unsigned int startup_brcm_irq(unsigned int irq)
 139 {
 140         enable_brcm_irq(irq);
 141
 142         return 0; /* never anything pending */
 143 }
 144
 145 unsigned int startup_brcm_none(unsigned int irq)
 146 {
 147         return 0;
 148 }
 149
 150 void end_brcm_irq(unsigned int irq)
 151 {
 152         if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 153                 enable_brcm_irq(irq);
 154 }
 155
 156 void end_brcm_none(unsigned int irq)
 157 {
 158 }
 159
 160 static struct hw_interrupt_type brcm_irq_type = {
 161         .typename       = "MIPS",
 162         .startup        = startup_brcm_irq,
 163         .shutdown       = disable_brcm_irq,
 164         .enable = enable_brcm_irq,
 165         .disable        = disable_brcm_irq,
 166         .ack    = ack_brcm_irq,
 167         .end    = end_brcm_irq,
 168         .set_affinity = NULL
 169 };
 170
 171 static struct hw_interrupt_type brcm_irq_no_end_type = {
 172         .typename       = "MIPS",
 173         .startup        = startup_brcm_none,
 174         .shutdown       = disable_brcm_irq,
 175         .enable = enable_brcm_irq,
 176         .disable        = disable_brcm_irq,
 177         .ack    = ack_brcm_irq,
 178         .end    = end_brcm_none,
 179         .set_affinity = NULL
 180 };
 181
 182 void __init arch_init_irq(void)
 183 {
 184         int i;
 185
 186         clear_c0_status(ST0_BEV);
 187         change_c0_status(ST0_IM, (IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | IE_IRQ3 | IE_IRQ4));
 188
 189         for (i = 0; i < NR_IRQS; i++) {
 190                 irq_desc[i].status = IRQ_DISABLED;
 191                 irq_desc[i].action = 0;
 192                 irq_desc[i].depth = 1;
 193                 irq_desc[i].chip = &brcm_irq_type;
 194         }
 195 }
 196
 197 int request_external_irq(unsigned int irq,
 198         FN_HANDLER handler,
 199                 unsigned long irqflags,
 200                 const char * devname,
 201                 void *dev_id)
 202 {
 203         unsigned long flags;
 204
 205         local_irq_save(flags);
 206
 207         PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_CLEAR_SHFT));      // Clear
 208         PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_MASK_SHFT));      // Mask
 209         PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_INSENS_SHFT));    // Edge insesnsitive
 210         PERF->ExtIrqCfg |= (1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_LEVEL_SHFT));      // Level triggered
 211         PERF->ExtIrqCfg &= ~(1 << (irq - INTERRUPT_ID_EXTERNAL_0 + EI_SENSE_SHFT));     // Low level
 212
 213         local_irq_restore(flags);
 214
 215         return( request_irq(irq, handler, irqflags, devname, dev_id) );
 216 }
 217
 218 /* VxWorks compatibility function(s). */
 219
 220 unsigned int BcmHalMapInterrupt(FN_HANDLER pfunc, unsigned int param,
 221         unsigned int interruptId)
 222 {
 223         int nRet = -1;
 224         char *devname;
 225
 226         devname = kmalloc(16, GFP_KERNEL);
 227         if (devname)
 228                 sprintf( devname, "brcm_%d", interruptId );
 229
 230         /* Set the IRQ description to not automatically enable the interrupt at
 231          * the end of an ISR.  The driver that handles the interrupt must
 232          * explicitly call BcmHalInterruptEnable or enable_brcm_irq.  This behavior
 233          * is consistent with interrupt handling on VxWorks.
 234          */
 235         irq_desc[interruptId].chip = &brcm_irq_no_end_type;
 236
 237         if( interruptId >= INTERNAL_ISR_TABLE_OFFSET )
 238         {
 239                 nRet = request_irq( interruptId, pfunc, SA_SAMPLE_RANDOM | SA_INTERRUPT,
 240                         devname, (void *) param );
 241         }
 242         else if (interruptId >= INTERRUPT_ID_EXTERNAL_0 && interruptId <= INTERRUPT_ID_EXTERNAL_3)
 243         {
 244                 nRet = request_external_irq( interruptId, pfunc, SA_SAMPLE_RANDOM | SA_INTERRUPT,
 245                         devname, (void *) param );
 246         }
 247
 248         return( nRet );
 249 }
 250
 251
 252 EXPORT_SYMBOL(enable_brcm_irq);
 253 EXPORT_SYMBOL(disable_brcm_irq);
 254 EXPORT_SYMBOL(request_external_irq);
 255 EXPORT_SYMBOL(BcmHalMapInterrupt);
 256