hw/etraxfs_timer.c

   1 /*
   2  * QEMU ETRAX Timers
   3  *
   4  * Copyright (c) 2007 Edgar E. Iglesias, Axis Communications AB.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include <stdio.h>
  25 #include <sys/time.h>
  26 #include "hw.h"
  27 #include "sysemu.h"
  28 #include "qemu-timer.h"
  29 #include "etraxfs.h"
  30
  31 #define D(x)
  32
  33 #define RW_TMR0_DIV   0x00
  34 #define R_TMR0_DATA   0x04
  35 #define RW_TMR0_CTRL  0x08
  36 #define RW_TMR1_DIV   0x10
  37 #define R_TMR1_DATA   0x14
  38 #define RW_TMR1_CTRL  0x18
  39 #define R_TIME        0x38
  40 #define RW_WD_CTRL    0x40
  41 #define R_WD_STAT     0x44
  42 #define RW_INTR_MASK  0x48
  43 #define RW_ACK_INTR   0x4c
  44 #define R_INTR        0x50
  45 #define R_MASKED_INTR 0x54
  46
  47 struct fs_timer_t {
  48         CPUState *env;
  49         qemu_irq *irq;
  50         qemu_irq *nmi;
  51
  52         QEMUBH *bh_t0;
  53         QEMUBH *bh_t1;
  54         QEMUBH *bh_wd;
  55         ptimer_state *ptimer_t0;
  56         ptimer_state *ptimer_t1;
  57         ptimer_state *ptimer_wd;
  58         struct timeval last;
  59
  60         int wd_hits;
  61
  62         /* Control registers.  */
  63         uint32_t rw_tmr0_div;
  64         uint32_t r_tmr0_data;
  65         uint32_t rw_tmr0_ctrl;
  66
  67         uint32_t rw_tmr1_div;
  68         uint32_t r_tmr1_data;
  69         uint32_t rw_tmr1_ctrl;
  70
  71         uint32_t rw_wd_ctrl;
  72
  73         uint32_t rw_intr_mask;
  74         uint32_t rw_ack_intr;
  75         uint32_t r_intr;
  76         uint32_t r_masked_intr;
  77 };
  78
  79 static uint32_t timer_readl (void *opaque, target_phys_addr_t addr)
  80 {
  81         struct fs_timer_t *t = opaque;
  82         uint32_t r = 0;
  83
  84         switch (addr) {
  85         case R_TMR0_DATA:
  86                 r = ptimer_get_count(t->ptimer_t0);
  87                 break;
  88         case R_TMR1_DATA:
  89                 r = ptimer_get_count(t->ptimer_t1);
  90                 break;
  91         case R_TIME:
  92                 r = qemu_get_clock(vm_clock) / 10;
  93                 break;
  94         case RW_INTR_MASK:
  95                 r = t->rw_intr_mask;
  96                 break;
  97         case R_MASKED_INTR:
  98                 r = t->r_intr & t->rw_intr_mask;
  99                 break;
 100         default:
 101                 D(printf ("%s %x\n", __func__, addr));
 102                 break;
 103         }
 104         return r;
 105 }
 106
 107 #define TIMER_SLOWDOWN 1
 108 static void update_ctrl(struct fs_timer_t *t, int tnum)
 109 {
 110         unsigned int op;
 111         unsigned int freq;
 112         unsigned int freq_hz;
 113         unsigned int div;
 114         uint32_t ctrl;
 115
 116         ptimer_state *timer;
 117
 118         if (tnum == 0) {
 119                 ctrl = t->rw_tmr0_ctrl;
 120                 div = t->rw_tmr0_div;
 121                 timer = t->ptimer_t0;
 122         } else {
 123                 ctrl = t->rw_tmr1_ctrl;
 124                 div = t->rw_tmr1_div;
 125                 timer = t->ptimer_t1;
 126         }
 127
 128
 129         op = ctrl & 3;
 130         freq = ctrl >> 2;
 131         freq_hz = 32000000;
 132
 133         switch (freq)
 134         {
 135         case 0:
 136         case 1:
 137                 D(printf ("extern or disabled timer clock?\n"));
 138                 break;
 139         case 4: freq_hz =  29493000; break;
 140         case 5: freq_hz =  32000000; break;
 141         case 6: freq_hz =  32768000; break;
 142         case 7: freq_hz = 100000000; break;
 143         default:
 144                 abort();
 145                 break;
 146         }
 147
 148         D(printf ("freq_hz=%d div=%d\n", freq_hz, div));
 149         div = div * TIMER_SLOWDOWN;
 150         div /= 1000;
 151         freq_hz /= 1000;
 152         ptimer_set_freq(timer, freq_hz);
 153         ptimer_set_limit(timer, div, 0);
 154
 155         switch (op)
 156         {
 157                 case 0:
 158                         /* Load.  */
 159                         ptimer_set_limit(timer, div, 1);
 160                         break;
 161                 case 1:
 162                         /* Hold.  */
 163                         ptimer_stop(timer);
 164                         break;
 165                 case 2:
 166                         /* Run.  */
 167                         ptimer_run(timer, 0);
 168                         break;
 169                 default:
 170                         abort();
 171                         break;
 172         }
 173 }
 174
 175 static void timer_update_irq(struct fs_timer_t *t)
 176 {
 177         t->r_intr &= ~(t->rw_ack_intr);
 178         t->r_masked_intr = t->r_intr & t->rw_intr_mask;
 179
 180         D(printf("%s: masked_intr=%x\n", __func__, t->r_masked_intr));
 181         if (t->r_masked_intr)
 182                 qemu_irq_raise(t->irq[0]);
 183         else
 184                 qemu_irq_lower(t->irq[0]);
 185 }
 186
 187 static void timer0_hit(void *opaque)
 188 {
 189         struct fs_timer_t *t = opaque;
 190         t->r_intr |= 1;
 191         timer_update_irq(t);
 192 }
 193
 194 static void timer1_hit(void *opaque)
 195 {
 196         struct fs_timer_t *t = opaque;
 197         t->r_intr |= 2;
 198         timer_update_irq(t);
 199 }
 200
 201 static void watchdog_hit(void *opaque)
 202 {
 203         struct fs_timer_t *t = opaque;
 204         if (t->wd_hits == 0) {
 205                 /* real hw gives a single tick before reseting but we are
 206                    a bit friendlier to compensate for our slower execution.  */
 207                 ptimer_set_count(t->ptimer_wd, 10);
 208                 ptimer_run(t->ptimer_wd, 1);
 209                 qemu_irq_raise(t->nmi[0]);
 210         }
 211         else
 212                 qemu_system_reset_request();
 213
 214         t->wd_hits++;
 215 }
 216
 217 static inline void timer_watchdog_update(struct fs_timer_t *t, uint32_t value)
 218 {
 219         unsigned int wd_en = t->rw_wd_ctrl & (1 << 8);
 220         unsigned int wd_key = t->rw_wd_ctrl >> 9;
 221         unsigned int wd_cnt = t->rw_wd_ctrl & 511;
 222         unsigned int new_key = value >> 9 & ((1 << 7) - 1);
 223         unsigned int new_cmd = (value >> 8) & 1;
 224
 225         /* If the watchdog is enabled, they written key must match the
 226            complement of the previous.  */
 227         wd_key = ~wd_key & ((1 << 7) - 1);
 228
 229         if (wd_en && wd_key != new_key)
 230                 return;
 231
 232         D(printf("en=%d new_key=%x oldkey=%x cmd=%d cnt=%d\n",
 233                  wd_en, new_key, wd_key, new_cmd, wd_cnt));
 234
 235         if (t->wd_hits)
 236                 qemu_irq_lower(t->nmi[0]);
 237
 238         t->wd_hits = 0;
 239
 240         ptimer_set_freq(t->ptimer_wd, 760);
 241         if (wd_cnt == 0)
 242                 wd_cnt = 256;
 243         ptimer_set_count(t->ptimer_wd, wd_cnt);
 244         if (new_cmd)
 245                 ptimer_run(t->ptimer_wd, 1);
 246         else
 247                 ptimer_stop(t->ptimer_wd);
 248
 249         t->rw_wd_ctrl = value;
 250 }
 251
 252 static void
 253 timer_writel (void *opaque, target_phys_addr_t addr, uint32_t value)
 254 {
 255         struct fs_timer_t *t = opaque;
 256
 257         switch (addr)
 258         {
 259                 case RW_TMR0_DIV:
 260                         t->rw_tmr0_div = value;
 261                         break;
 262                 case RW_TMR0_CTRL:
 263                         D(printf ("RW_TMR0_CTRL=%x\n", value));
 264                         t->rw_tmr0_ctrl = value;
 265                         update_ctrl(t, 0);
 266                         break;
 267                 case RW_TMR1_DIV:
 268                         t->rw_tmr1_div = value;
 269                         break;
 270                 case RW_TMR1_CTRL:
 271                         D(printf ("RW_TMR1_CTRL=%x\n", value));
 272                         t->rw_tmr1_ctrl = value;
 273                         update_ctrl(t, 1);
 274                         break;
 275                 case RW_INTR_MASK:
 276                         D(printf ("RW_INTR_MASK=%x\n", value));
 277                         t->rw_intr_mask = value;
 278                         timer_update_irq(t);
 279                         break;
 280                 case RW_WD_CTRL:
 281                         timer_watchdog_update(t, value);
 282                         break;
 283                 case RW_ACK_INTR:
 284                         t->rw_ack_intr = value;
 285                         timer_update_irq(t);
 286                         t->rw_ack_intr = 0;
 287                         break;
 288                 default:
 289                         printf ("%s " TARGET_FMT_plx " %x\n",
 290                                 __func__, addr, value);
 291                         break;
 292         }
 293 }
 294
 295 static CPUReadMemoryFunc *timer_read[] = {
 296         NULL, NULL,
 297         &timer_readl,
 298 };
 299
 300 static CPUWriteMemoryFunc *timer_write[] = {
 301         NULL, NULL,
 302         &timer_writel,
 303 };
 304
 305 static void etraxfs_timer_reset(void *opaque)
 306 {
 307         struct fs_timer_t *t = opaque;
 308
 309         ptimer_stop(t->ptimer_t0);
 310         ptimer_stop(t->ptimer_t1);
 311         ptimer_stop(t->ptimer_wd);
 312         t->rw_wd_ctrl = 0;
 313         t->r_intr = 0;
 314         t->rw_intr_mask = 0;
 315         qemu_irq_lower(t->irq[0]);
 316 }
 317
 318 void etraxfs_timer_init(CPUState *env, qemu_irq *irqs, qemu_irq *nmi,
 319                         target_phys_addr_t base)
 320 {
 321         static struct fs_timer_t *t;
 322         int timer_regs;
 323
 324         t = qemu_mallocz(sizeof *t);
 325
 326         t->bh_t0 = qemu_bh_new(timer0_hit, t);
 327         t->bh_t1 = qemu_bh_new(timer1_hit, t);
 328         t->bh_wd = qemu_bh_new(watchdog_hit, t);
 329         t->ptimer_t0 = ptimer_init(t->bh_t0);
 330         t->ptimer_t1 = ptimer_init(t->bh_t1);
 331         t->ptimer_wd = ptimer_init(t->bh_wd);
 332         t->irq = irqs;
 333         t->nmi = nmi;
 334         t->env = env;
 335
 336         timer_regs = cpu_register_io_memory(0, timer_read, timer_write, t);
 337         cpu_register_physical_memory (base, 0x5c, timer_regs);
 338
 339         qemu_register_reset(etraxfs_timer_reset, t);
 340 }