cpu/mpc5xx/interrupts.c

   1 /*
   2  * (C) Copyright 2000-2002      Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   3  * (C) Copyright 2003           Martin Winistoerfer, martinwinistoerfer@gmx.ch.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) 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,
  21  */
  22
  23 /*
  24  * File:                interrupt.c
  25  *
  26  * Discription:         Contains interrupt routines needed by U-Boot
  27  *
  28  */
  29
  30 #include <common.h>
  31 #include <command.h>
  32 #include <mpc5xx.h>
  33 #include <asm/processor.h>
  34
  35 #if defined(CONFIG_PATI)
  36 /* PATI uses IRQs for PCI doorbell */
  37 #undef NR_IRQS
  38 #define NR_IRQS 16
  39 #endif
  40
  41 struct interrupt_action {
  42         interrupt_handler_t *handler;
  43         void *arg;
  44         int count;
  45 };
  46
  47 static struct interrupt_action irq_vecs[NR_IRQS];
  48
  49 /*
  50  * Initialise interrupts
  51  */
  52
  53 int interrupt_init_cpu (ulong *decrementer_count)
  54 {
  55         volatile immap_t *immr = (immap_t *) CFG_IMMR;
  56         int vec;
  57
  58         /* Decrementer used here for status led */
  59         *decrementer_count = get_tbclk () / CFG_HZ;
  60
  61         /* Disable all interrupts */
  62         immr->im_siu_conf.sc_simask = 0;
  63         for (vec=0; vec<NR_IRQS; vec++) {
  64                 irq_vecs[vec].handler = NULL;
  65                 irq_vecs[vec].arg = NULL;
  66                 irq_vecs[vec].count = 0;
  67         }
  68
  69         return (0);
  70 }
  71
  72 /*
  73  * Handle external interrupts
  74  */
  75 void external_interrupt (struct pt_regs *regs)
  76 {
  77         volatile immap_t *immr = (immap_t *) CFG_IMMR;
  78         int irq;
  79         ulong simask, newmask;
  80         ulong vec, v_bit;
  81
  82         /*
  83          * read the SIVEC register and shift the bits down
  84          * to get the irq number
  85          */
  86         vec = immr->im_siu_conf.sc_sivec;
  87         irq = vec >> 26;
  88         v_bit = 0x80000000UL >> irq;
  89
  90         /*
  91          * Read Interrupt Mask Register and Mask Interrupts
  92          */
  93         simask = immr->im_siu_conf.sc_simask;
  94         newmask = simask & (~(0xFFFF0000 >> irq));
  95         immr->im_siu_conf.sc_simask = newmask;
  96
  97         if (!(irq & 0x1)) {             /* External Interrupt ?     */
  98                 ulong siel;
  99
 100                 /*
 101                  * Read Interrupt Edge/Level Register
 102                  */
 103                 siel = immr->im_siu_conf.sc_siel;
 104
 105                 if (siel & v_bit) {     /* edge triggered interrupt ?   */
 106                         /*
 107                          * Rewrite SIPEND Register to clear interrupt
 108                          */
 109                         immr->im_siu_conf.sc_sipend = v_bit;
 110                 }
 111         }
 112
 113         if (irq_vecs[irq].handler != NULL) {
 114                 irq_vecs[irq].handler (irq_vecs[irq].arg);
 115         } else {
 116                 printf ("\nBogus External Interrupt IRQ %d Vector %ld\n",
 117                                 irq, vec);
 118                 /* turn off the bogus interrupt to avoid it from now */
 119                 simask &= ~v_bit;
 120         }
 121         /*
 122          * Re-Enable old Interrupt Mask
 123          */
 124         immr->im_siu_conf.sc_simask = simask;
 125 }
 126
 127 /*
 128  * Install and free an interrupt handler
 129  */
 130 void irq_install_handler (int vec, interrupt_handler_t * handler,
 131                                                   void *arg)
 132 {
 133         volatile immap_t *immr = (immap_t *) CFG_IMMR;
 134         /* SIU interrupt */
 135         if (irq_vecs[vec].handler != NULL) {
 136                 printf ("SIU interrupt %d 0x%x\n",
 137                         vec,
 138                         (uint) handler);
 139         }
 140         irq_vecs[vec].handler = handler;
 141         irq_vecs[vec].arg = arg;
 142         immr->im_siu_conf.sc_simask |= 1 << (31 - vec);
 143 #if 0
 144         printf ("Install SIU interrupt for vector %d ==> %p\n",
 145                 vec, handler);
 146 #endif
 147 }
 148
 149 void irq_free_handler (int vec)
 150 {
 151         volatile immap_t *immr = (immap_t *) CFG_IMMR;
 152         /* SIU interrupt */
 153 #if 0
 154         printf ("Free CPM interrupt for vector %d\n",
 155                 vec);
 156 #endif
 157         immr->im_siu_conf.sc_simask &= ~(1 << (31 - vec));
 158         irq_vecs[vec].handler = NULL;
 159         irq_vecs[vec].arg = NULL;
 160 }
 161
 162 /*
 163  *  Timer interrupt - gets called when  bit 0 of DEC changes from
 164  *  0. Decrementer is enabled with bit TBE in TBSCR.
 165  */
 166 void timer_interrupt_cpu (struct pt_regs *regs)
 167 {
 168         volatile immap_t *immr = (immap_t *) CFG_IMMR;
 169
 170 #if 0
 171         printf ("*** Timer Interrupt *** ");
 172 #endif
 173         /* Reset Timer Status Bit and Timers Interrupt Status */
 174         immr->im_clkrstk.cark_plprcrk = KAPWR_KEY;
 175         __asm__ ("nop");
 176         immr->im_clkrst.car_plprcr |= PLPRCR_TEXPS | PLPRCR_TMIST;
 177
 178         return;
 179 }
 180
 181 #if defined(CONFIG_CMD_IRQ)
 182 /*******************************************************************************
 183  *
 184  * irqinfo - print information about IRQs
 185  *
 186  */
 187 int do_irqinfo(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 188 {
 189         int vec;
 190
 191         printf ("\nInterrupt-Information:\n");
 192         printf ("Nr  Routine   Arg       Count\n");
 193
 194         for (vec=0; vec<NR_IRQS; vec++) {
 195                 if (irq_vecs[vec].handler != NULL) {
 196                         printf ("%02d  %08lx  %08lx  %d\n",
 197                                 vec,
 198                                 (ulong)irq_vecs[vec].handler,
 199                                 (ulong)irq_vecs[vec].arg,
 200                                 irq_vecs[vec].count);
 201                 }
 202         }
 203         return 0;
 204 }
 205
 206
 207 #endif