arch/mips/tx4938/common/irq.c

   1 /*
   2  * linux/arch/mips/tx4938/common/irq.c
   3  *
   4  * Common tx4938 irq handler
   5  * Copyright (C) 2000-2001 Toshiba Corporation
   6  *
   7  * 2003-2005 (c) MontaVista Software, Inc. This file is licensed under the
   8  * terms of the GNU General Public License version 2. This program is
   9  * licensed "as is" without any warranty of any kind, whether express
  10  * or implied.
  11  *
  12  * Support for TX4938 in 2.6 - Manish Lachwani (mlachwani@mvista.com)
  13  */
  14 #include <linux/errno.h>
  15 #include <linux/init.h>
  16 #include <linux/kernel_stat.h>
  17 #include <linux/module.h>
  18 #include <linux/signal.h>
  19 #include <linux/sched.h>
  20 #include <linux/types.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/ioport.h>
  23 #include <linux/timex.h>
  24 #include <linux/slab.h>
  25 #include <linux/random.h>
  26 #include <linux/irq.h>
  27 #include <asm/bitops.h>
  28 #include <asm/bootinfo.h>
  29 #include <asm/io.h>
  30 #include <asm/irq.h>
  31 #include <asm/mipsregs.h>
  32 #include <asm/system.h>
  33 #include <asm/wbflush.h>
  34 #include <asm/tx4938/rbtx4938.h>
  35
  36 /**********************************************************************************/
  37 /* Forwad definitions for all pic's                                               */
  38 /**********************************************************************************/
  39
  40 static void tx4938_irq_cp0_enable(unsigned int irq);
  41 static void tx4938_irq_cp0_disable(unsigned int irq);
  42 static void tx4938_irq_cp0_end(unsigned int irq);
  43
  44 static void tx4938_irq_pic_enable(unsigned int irq);
  45 static void tx4938_irq_pic_disable(unsigned int irq);
  46 static void tx4938_irq_pic_end(unsigned int irq);
  47
  48 /**********************************************************************************/
  49 /* Kernel structs for all pic's                                                   */
  50 /**********************************************************************************/
  51
  52 #define TX4938_CP0_NAME "TX4938-CP0"
  53 static struct irq_chip tx4938_irq_cp0_type = {
  54         .typename = TX4938_CP0_NAME,
  55         .ack = tx4938_irq_cp0_disable,
  56         .mask = tx4938_irq_cp0_disable,
  57         .mask_ack = tx4938_irq_cp0_disable,
  58         .unmask = tx4938_irq_cp0_enable,
  59         .end = tx4938_irq_cp0_end,
  60 };
  61
  62 #define TX4938_PIC_NAME "TX4938-PIC"
  63 static struct irq_chip tx4938_irq_pic_type = {
  64         .typename = TX4938_PIC_NAME,
  65         .ack = tx4938_irq_pic_disable,
  66         .mask = tx4938_irq_pic_disable,
  67         .mask_ack = tx4938_irq_pic_disable,
  68         .unmask = tx4938_irq_pic_enable,
  69         .end = tx4938_irq_pic_end,
  70 };
  71
  72 static struct irqaction tx4938_irq_pic_action = {
  73         .handler = no_action,
  74         .flags = 0,
  75         .mask = CPU_MASK_NONE,
  76         .name = TX4938_PIC_NAME
  77 };
  78
  79 /**********************************************************************************/
  80 /* Functions for cp0                                                              */
  81 /**********************************************************************************/
  82
  83 #define tx4938_irq_cp0_mask(irq) ( 1 << ( irq-TX4938_IRQ_CP0_BEG+8 ) )
  84
  85 static void __init
  86 tx4938_irq_cp0_init(void)
  87 {
  88         int i;
  89
  90         for (i = TX4938_IRQ_CP0_BEG; i <= TX4938_IRQ_CP0_END; i++)
  91                 set_irq_chip(i, &tx4938_irq_cp0_type);
  92 }
  93
  94 static void
  95 tx4938_irq_cp0_enable(unsigned int irq)
  96 {
  97         set_c0_status(tx4938_irq_cp0_mask(irq));
  98 }
  99
 100 static void
 101 tx4938_irq_cp0_disable(unsigned int irq)
 102 {
 103         clear_c0_status(tx4938_irq_cp0_mask(irq));
 104 }
 105
 106 static void
 107 tx4938_irq_cp0_end(unsigned int irq)
 108 {
 109         if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
 110                 tx4938_irq_cp0_enable(irq);
 111         }
 112 }
 113
 114 /**********************************************************************************/
 115 /* Functions for pic                                                              */
 116 /**********************************************************************************/
 117
 118 u32
 119 tx4938_irq_pic_addr(int irq)
 120 {
 121         /* MVMCP -- need to formulize this */
 122         irq -= TX4938_IRQ_PIC_BEG;
 123
 124         switch (irq) {
 125         case 17:
 126         case 16:
 127         case 1:
 128         case 0:{
 129                         return (TX4938_MKA(TX4938_IRC_IRLVL0));
 130                 }
 131         case 19:
 132         case 18:
 133         case 3:
 134         case 2:{
 135                         return (TX4938_MKA(TX4938_IRC_IRLVL1));
 136                 }
 137         case 21:
 138         case 20:
 139         case 5:
 140         case 4:{
 141                         return (TX4938_MKA(TX4938_IRC_IRLVL2));
 142                 }
 143         case 23:
 144         case 22:
 145         case 7:
 146         case 6:{
 147                         return (TX4938_MKA(TX4938_IRC_IRLVL3));
 148                 }
 149         case 25:
 150         case 24:
 151         case 9:
 152         case 8:{
 153                         return (TX4938_MKA(TX4938_IRC_IRLVL4));
 154                 }
 155         case 27:
 156         case 26:
 157         case 11:
 158         case 10:{
 159                         return (TX4938_MKA(TX4938_IRC_IRLVL5));
 160                 }
 161         case 29:
 162         case 28:
 163         case 13:
 164         case 12:{
 165                         return (TX4938_MKA(TX4938_IRC_IRLVL6));
 166                 }
 167         case 31:
 168         case 30:
 169         case 15:
 170         case 14:{
 171                         return (TX4938_MKA(TX4938_IRC_IRLVL7));
 172                 }
 173         }
 174
 175         return 0;
 176 }
 177
 178 u32
 179 tx4938_irq_pic_mask(int irq)
 180 {
 181         /* MVMCP -- need to formulize this */
 182         irq -= TX4938_IRQ_PIC_BEG;
 183
 184         switch (irq) {
 185         case 31:
 186         case 29:
 187         case 27:
 188         case 25:
 189         case 23:
 190         case 21:
 191         case 19:
 192         case 17:{
 193                         return (0x07000000);
 194                 }
 195         case 30:
 196         case 28:
 197         case 26:
 198         case 24:
 199         case 22:
 200         case 20:
 201         case 18:
 202         case 16:{
 203                         return (0x00070000);
 204                 }
 205         case 15:
 206         case 13:
 207         case 11:
 208         case 9:
 209         case 7:
 210         case 5:
 211         case 3:
 212         case 1:{
 213                         return (0x00000700);
 214                 }
 215         case 14:
 216         case 12:
 217         case 10:
 218         case 8:
 219         case 6:
 220         case 4:
 221         case 2:
 222         case 0:{
 223                         return (0x00000007);
 224                 }
 225         }
 226         return 0x00000000;
 227 }
 228
 229 static void
 230 tx4938_irq_pic_modify(unsigned pic_reg, unsigned clr_bits, unsigned set_bits)
 231 {
 232         unsigned long val = 0;
 233
 234         val = TX4938_RD(pic_reg);
 235         val &= (~clr_bits);
 236         val |= (set_bits);
 237         TX4938_WR(pic_reg, val);
 238         mmiowb();
 239         TX4938_RD(pic_reg);
 240 }
 241
 242 static void __init
 243 tx4938_irq_pic_init(void)
 244 {
 245         int i;
 246
 247         for (i = TX4938_IRQ_PIC_BEG; i <= TX4938_IRQ_PIC_END; i++)
 248                 set_irq_chip(i, &tx4938_irq_pic_type);
 249
 250         setup_irq(TX4938_IRQ_NEST_PIC_ON_CP0, &tx4938_irq_pic_action);
 251
 252         TX4938_WR(0xff1ff640, 0x6);     /* irq level mask -- only accept hightest */
 253         TX4938_WR(0xff1ff600, TX4938_RD(0xff1ff600) | 0x1);     /* irq enable */
 254 }
 255
 256 static void
 257 tx4938_irq_pic_enable(unsigned int irq)
 258 {
 259         tx4938_irq_pic_modify(tx4938_irq_pic_addr(irq), 0,
 260                               tx4938_irq_pic_mask(irq));
 261 }
 262
 263 static void
 264 tx4938_irq_pic_disable(unsigned int irq)
 265 {
 266         tx4938_irq_pic_modify(tx4938_irq_pic_addr(irq),
 267                               tx4938_irq_pic_mask(irq), 0);
 268 }
 269
 270 static void
 271 tx4938_irq_pic_end(unsigned int irq)
 272 {
 273         if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS))) {
 274                 tx4938_irq_pic_enable(irq);
 275         }
 276 }
 277
 278 /**********************************************************************************/
 279 /* Main init functions                                                            */
 280 /**********************************************************************************/
 281
 282 void __init
 283 tx4938_irq_init(void)
 284 {
 285         tx4938_irq_cp0_init();
 286         tx4938_irq_pic_init();
 287 }
 288
 289 int
 290 tx4938_irq_nested(void)
 291 {
 292         int sw_irq = 0;
 293         u32 level2;
 294
 295         level2 = TX4938_RD(0xff1ff6a0);
 296         if ((level2 & 0x10000) == 0) {
 297                 level2 &= 0x1f;
 298                 sw_irq = TX4938_IRQ_PIC_BEG + level2;
 299                 if (sw_irq == 26) {
 300                         {
 301                                 extern int toshiba_rbtx4938_irq_nested(int sw_irq);
 302                                 sw_irq = toshiba_rbtx4938_irq_nested(sw_irq);
 303                         }
 304                 }
 305         }
 306
 307         wbflush();
 308         return sw_irq;
 309 }
 310
 311 asmlinkage void plat_irq_dispatch(void)
 312 {
 313         unsigned int pending = read_c0_cause() & read_c0_status();
 314
 315         if (pending & STATUSF_IP7)
 316                 do_IRQ(TX4938_IRQ_CPU_TIMER);
 317         else if (pending & STATUSF_IP2) {
 318                 int irq = tx4938_irq_nested();
 319                 if (irq)
 320                         do_IRQ(irq);
 321                 else
 322                         spurious_interrupt();
 323         } else if (pending & STATUSF_IP1)
 324                 do_IRQ(TX4938_IRQ_USER1);
 325         else if (pending & STATUSF_IP0)
 326                 do_IRQ(TX4938_IRQ_USER0);
 327 }