arch/ppc/syslib/mpc52xx_pic.c

   1 /*
   2  * Programmable Interrupt Controller functions for the Freescale MPC52xx
   3  * embedded CPU.
   4  *
   5  *
   6  * Maintainer : Sylvain Munaut <tnt@246tNt.com>
   7  *
   8  * Based on (well, mostly copied from) the code from the 2.4 kernel by
   9  * Dale Farnsworth <dfarnsworth@mvista.com> and Kent Borg.
  10  *
  11  * Copyright (C) 2004 Sylvain Munaut <tnt@246tNt.com>
  12  * Copyright (C) 2003 Montavista Software, Inc
  13  *
  14  * This file is licensed under the terms of the GNU General Public License
  15  * version 2. This program is licensed "as is" without any warranty of any
  16  * kind, whether express or implied.
  17  */
  18
  19 #include <linux/stddef.h>
  20 #include <linux/init.h>
  21 #include <linux/sched.h>
  22 #include <linux/signal.h>
  23 #include <linux/stddef.h>
  24 #include <linux/delay.h>
  25 #include <linux/irq.h>
  26
  27 #include <asm/io.h>
  28 #include <asm/processor.h>
  29 #include <asm/system.h>
  30 #include <asm/irq.h>
  31 #include <asm/mpc52xx.h>
  32
  33
  34 static struct mpc52xx_intr __iomem *intr;
  35 static struct mpc52xx_sdma __iomem *sdma;
  36
  37 static void
  38 mpc52xx_ic_disable(unsigned int irq)
  39 {
  40         u32 val;
  41
  42         if (irq == MPC52xx_IRQ0) {
  43                 val = in_be32(&intr->ctrl);
  44                 val &= ~(1 << 11);
  45                 out_be32(&intr->ctrl, val);
  46         }
  47         else if (irq < MPC52xx_IRQ1) {
  48                 BUG();
  49         }
  50         else if (irq <= MPC52xx_IRQ3) {
  51                 val = in_be32(&intr->ctrl);
  52                 val &= ~(1 << (10 - (irq - MPC52xx_IRQ1)));
  53                 out_be32(&intr->ctrl, val);
  54         }
  55         else if (irq < MPC52xx_SDMA_IRQ_BASE) {
  56                 val = in_be32(&intr->main_mask);
  57                 val |= 1 << (16 - (irq - MPC52xx_MAIN_IRQ_BASE));
  58                 out_be32(&intr->main_mask, val);
  59         }
  60         else if (irq < MPC52xx_PERP_IRQ_BASE) {
  61                 val = in_be32(&sdma->IntMask);
  62                 val |= 1 << (irq - MPC52xx_SDMA_IRQ_BASE);
  63                 out_be32(&sdma->IntMask, val);
  64         }
  65         else {
  66                 val = in_be32(&intr->per_mask);
  67                 val |= 1 << (31 - (irq - MPC52xx_PERP_IRQ_BASE));
  68                 out_be32(&intr->per_mask, val);
  69         }
  70 }
  71
  72 static void
  73 mpc52xx_ic_enable(unsigned int irq)
  74 {
  75         u32 val;
  76
  77         if (irq == MPC52xx_IRQ0) {
  78                 val = in_be32(&intr->ctrl);
  79                 val |= 1 << 11;
  80                 out_be32(&intr->ctrl, val);
  81         }
  82         else if (irq < MPC52xx_IRQ1) {
  83                 BUG();
  84         }
  85         else if (irq <= MPC52xx_IRQ3) {
  86                 val = in_be32(&intr->ctrl);
  87                 val |= 1 << (10 - (irq - MPC52xx_IRQ1));
  88                 out_be32(&intr->ctrl, val);
  89         }
  90         else if (irq < MPC52xx_SDMA_IRQ_BASE) {
  91                 val = in_be32(&intr->main_mask);
  92                 val &= ~(1 << (16 - (irq - MPC52xx_MAIN_IRQ_BASE)));
  93                 out_be32(&intr->main_mask, val);
  94         }
  95         else if (irq < MPC52xx_PERP_IRQ_BASE) {
  96                 val = in_be32(&sdma->IntMask);
  97                 val &= ~(1 << (irq - MPC52xx_SDMA_IRQ_BASE));
  98                 out_be32(&sdma->IntMask, val);
  99         }
 100         else {
 101                 val = in_be32(&intr->per_mask);
 102                 val &= ~(1 << (31 - (irq - MPC52xx_PERP_IRQ_BASE)));
 103                 out_be32(&intr->per_mask, val);
 104         }
 105 }
 106
 107 static void
 108 mpc52xx_ic_ack(unsigned int irq)
 109 {
 110         u32 val;
 111
 112         /*
 113          * Only some irqs are reset here, others in interrupting hardware.
 114          */
 115
 116         switch (irq) {
 117         case MPC52xx_IRQ0:
 118                 val = in_be32(&intr->ctrl);
 119                 val |= 0x08000000;
 120                 out_be32(&intr->ctrl, val);
 121                 break;
 122         case MPC52xx_CCS_IRQ:
 123                 val = in_be32(&intr->enc_status);
 124                 val |= 0x00000400;
 125                 out_be32(&intr->enc_status, val);
 126                 break;
 127         case MPC52xx_IRQ1:
 128                 val = in_be32(&intr->ctrl);
 129                 val |= 0x04000000;
 130                 out_be32(&intr->ctrl, val);
 131                 break;
 132         case MPC52xx_IRQ2:
 133                 val = in_be32(&intr->ctrl);
 134                 val |= 0x02000000;
 135                 out_be32(&intr->ctrl, val);
 136                 break;
 137         case MPC52xx_IRQ3:
 138                 val = in_be32(&intr->ctrl);
 139                 val |= 0x01000000;
 140                 out_be32(&intr->ctrl, val);
 141                 break;
 142         default:
 143                 if (irq >= MPC52xx_SDMA_IRQ_BASE
 144                     && irq < (MPC52xx_SDMA_IRQ_BASE + MPC52xx_SDMA_IRQ_NUM)) {
 145                         out_be32(&sdma->IntPend,
 146                                  1 << (irq - MPC52xx_SDMA_IRQ_BASE));
 147                 }
 148                 break;
 149         }
 150 }
 151
 152 static void
 153 mpc52xx_ic_disable_and_ack(unsigned int irq)
 154 {
 155         mpc52xx_ic_disable(irq);
 156         mpc52xx_ic_ack(irq);
 157 }
 158
 159 static void
 160 mpc52xx_ic_end(unsigned int irq)
 161 {
 162         if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
 163                 mpc52xx_ic_enable(irq);
 164 }
 165
 166 static struct hw_interrupt_type mpc52xx_ic = {
 167         .typename       = " MPC52xx  ",
 168         .enable         = mpc52xx_ic_enable,
 169         .disable        = mpc52xx_ic_disable,
 170         .ack            = mpc52xx_ic_disable_and_ack,
 171         .end            = mpc52xx_ic_end,
 172 };
 173
 174 void __init
 175 mpc52xx_init_irq(void)
 176 {
 177         int i;
 178         u32 intr_ctrl;
 179
 180         /* Remap the necessary zones */
 181         intr = ioremap(MPC52xx_PA(MPC52xx_INTR_OFFSET), MPC52xx_INTR_SIZE);
 182         sdma = ioremap(MPC52xx_PA(MPC52xx_SDMA_OFFSET), MPC52xx_SDMA_SIZE);
 183
 184         if ((intr==NULL) || (sdma==NULL))
 185                 panic("Can't ioremap PIC/SDMA register for init_irq !");
 186
 187         /* Disable all interrupt sources. */
 188         out_be32(&sdma->IntPend, 0xffffffff);   /* 1 means clear pending */
 189         out_be32(&sdma->IntMask, 0xffffffff);   /* 1 means disabled */
 190         out_be32(&intr->per_mask, 0x7ffffc00);  /* 1 means disabled */
 191         out_be32(&intr->main_mask, 0x00010fff); /* 1 means disabled */
 192         intr_ctrl = in_be32(&intr->ctrl);
 193         intr_ctrl &=    0x00ff0000;     /* Keeps IRQ[0-3] config */
 194         intr_ctrl |=    0x0f000000 |    /* clear IRQ 0-3 */
 195                         0x00001000 |    /* MEE master external enable */
 196                         0x00000000 |    /* 0 means disable IRQ 0-3 */
 197                         0x00000001;     /* CEb route critical normally */
 198         out_be32(&intr->ctrl, intr_ctrl);
 199
 200         /* Zero a bunch of the priority settings.  */
 201         out_be32(&intr->per_pri1, 0);
 202         out_be32(&intr->per_pri2, 0);
 203         out_be32(&intr->per_pri3, 0);
 204         out_be32(&intr->main_pri1, 0);
 205         out_be32(&intr->main_pri2, 0);
 206
 207         /* Initialize irq_desc[i].chip's with mpc52xx_ic. */
 208         for (i = 0; i < NR_IRQS; i++) {
 209                 irq_desc[i].chip = &mpc52xx_ic;
 210                 irq_desc[i].status = IRQ_LEVEL;
 211         }
 212
 213         #define IRQn_MODE(intr_ctrl,irq) (((intr_ctrl) >> (22-(i<<1))) & 0x03)
 214         for (i=0 ; i<4 ; i++) {
 215                 int mode;
 216                 mode = IRQn_MODE(intr_ctrl,i);
 217                 if ((mode == 0x1) || (mode == 0x2))
 218                         irq_desc[i?MPC52xx_IRQ1+i-1:MPC52xx_IRQ0].status = 0;
 219         }
 220 }
 221
 222 int
 223 mpc52xx_get_irq(void)
 224 {
 225         u32 status;
 226         int irq = -1;
 227
 228         status = in_be32(&intr->enc_status);
 229
 230         if (status & 0x00000400) {              /* critical */
 231                 irq = (status >> 8) & 0x3;
 232                 if (irq == 2)                   /* high priority peripheral */
 233                         goto peripheral;
 234                 irq += MPC52xx_CRIT_IRQ_BASE;
 235         }
 236         else if (status & 0x00200000) {         /* main */
 237                 irq = (status >> 16) & 0x1f;
 238                 if (irq == 4)                   /* low priority peripheral */
 239                         goto peripheral;
 240                 irq += MPC52xx_MAIN_IRQ_BASE;
 241         }
 242         else if (status & 0x20000000) {         /* peripheral */
 243 peripheral:
 244                 irq = (status >> 24) & 0x1f;
 245                 if (irq == 0) {                 /* bestcomm */
 246                         status = in_be32(&sdma->IntPend);
 247                         irq = ffs(status) + MPC52xx_SDMA_IRQ_BASE-1;
 248                 }
 249                 else
 250                         irq += MPC52xx_PERP_IRQ_BASE;
 251         }
 252
 253         return irq;
 254 }
 255