1 /* 2 * 6522 Versatile Interface Adapter (VIA) 3 * 4 * There are two of these on the Mac II. Some IRQ's are vectored 5 * via them as are assorted bits and bobs - eg RTC, ADB. 6 * 7 * CSA: Motorola seems to have removed documentation on the 6522 from 8 * their web site; try 9 * http://nerini.drf.com/vectrex/other/text/chips/6522/ 10 * http://www.zymurgy.net/classic/vic20/vicdet1.htm 11 * and 12 * http://193.23.168.87/mikro_laborversuche/via_iobaustein/via6522_1.html 13 * for info. A full-text web search on 6522 AND VIA will probably also 14 * net some usefulness. <cananian@alumni.princeton.edu> 20apr1999 15 * 16 * Additional data is here (the SY6522 was used in the Mac II etc): 17 * http://www.6502.org/documents/datasheets/synertek/synertek_sy6522.pdf 18 * http://www.6502.org/documents/datasheets/synertek/synertek_sy6522_programming_reference.pdf 19 * 20 * PRAM/RTC access algorithms are from the NetBSD RTC toolkit version 1.08b 21 * by Erik Vogan and adapted to Linux by Joshua M. Thompson (funaho@jurai.org) 22 * 23 */ 24 25 #include <linux/types.h> 26 #include <linux/kernel.h> 27 #include <linux/mm.h> 28 #include <linux/delay.h> 29 #include <linux/init.h> 30 #include <linux/ide.h> 31 32 #include <asm/bootinfo.h> 33 #include <asm/macintosh.h> 34 #include <asm/macints.h> 35 #include <asm/machw.h> 36 #include <asm/mac_via.h> 37 #include <asm/mac_psc.h> 38 39 volatile __u8 *via1, *via2; 40 #if 0 41 /* See note in mac_via.h about how this is possibly not useful */ 42 volatile long *via_memory_bogon=(long *)&via_memory_bogon; 43 #endif 44 int rbv_present, via_alt_mapping; 45 __u8 rbv_clear; 46 47 /* 48 * Globals for accessing the VIA chip registers without having to 49 * check if we're hitting a real VIA or an RBV. Normally you could 50 * just hit the combined register (ie, vIER|rIER) but that seems to 51 * break on AV Macs...probably because they actually decode more than 52 * eight address bits. Why can't Apple engineers at least be 53 * _consistently_ lazy? - 1999-05-21 (jmt) 54 */ 55 56 static int gIER,gIFR,gBufA,gBufB; 57 58 /* 59 * Timer defs. 60 */ 61 62 #define TICK_SIZE 10000 63 #define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */ 64 #define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF) 65 #define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8) 66 67 /* To disable a NuBus slot on Quadras we make the slot IRQ lines outputs, set 68 * high. On RBV we just use the slot interrupt enable register. On Macs with 69 * genuine VIA chips we must use nubus_disabled to keep track of disabled slot 70 * interrupts. When any slot IRQ is disabled we mask the (edge triggered) CA1 71 * or "SLOTS" interrupt. When no slot is disabled, we unmask the CA1 interrupt. 72 * So, on genuine VIAs, having more than one NuBus IRQ can mean trouble, 73 * because closing one of those drivers can mask all of the NuBus interrupts. 74 * Also, since we can't mask the unregistered slot IRQs on genuine VIAs, it's 75 * possible to get interrupts from cards that MacOS or the ROM has configured 76 * but we have not. FWIW, "Designing Cards and Drivers for Macintosh II and 77 * Macintosh SE", page 9-8, says, a slot IRQ with no driver would crash MacOS. 78 */ 79 static u8 nubus_disabled; 80 81 void via_debug_dump(void); 82 irqreturn_t via1_irq(int, void *); 83 irqreturn_t via2_irq(int, void *); 84 irqreturn_t via_nubus_irq(int, void *); 85 void via_irq_enable(int irq); 86 void via_irq_disable(int irq); 87 void via_irq_clear(int irq); 88 89 extern irqreturn_t mac_scc_dispatch(int, void *); 90 extern int oss_present; 91 92 /* 93 * Initialize the VIAs 94 * 95 * First we figure out where they actually _are_ as well as what type of 96 * VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.) 97 * Then we pretty much clear them out and disable all IRQ sources. 98 * 99 * Note: the OSS is actually "detected" here and not in oss_init(). It just 100 * seems more logical to do it here since via_init() needs to know 101 * these things anyways. 102 */ 103 104 void __init via_init(void) 105 { 106 switch(macintosh_config->via_type) { 107 108 /* IIci, IIsi, IIvx, IIvi (P6xx), LC series */ 109 110 case MAC_VIA_IIci: 111 via1 = (void *) VIA1_BASE; 112 if (macintosh_config->ident == MAC_MODEL_IIFX) { 113 via2 = NULL; 114 rbv_present = 0; 115 oss_present = 1; 116 } else { 117 via2 = (void *) RBV_BASE; 118 rbv_present = 1; 119 oss_present = 0; 120 } 121 if (macintosh_config->ident == MAC_MODEL_LCIII) { 122 rbv_clear = 0x00; 123 } else { 124 /* on most RBVs (& unlike the VIAs), you */ 125 /* need to set bit 7 when you write to IFR */ 126 /* in order for your clear to occur. */ 127 rbv_clear = 0x80; 128 } 129 gIER = rIER; 130 gIFR = rIFR; 131 gBufA = rSIFR; 132 gBufB = rBufB; 133 break; 134 135 /* Quadra and early MacIIs agree on the VIA locations */ 136 137 case MAC_VIA_QUADRA: 138 case MAC_VIA_II: 139 via1 = (void *) VIA1_BASE; 140 via2 = (void *) VIA2_BASE; 141 rbv_present = 0; 142 oss_present = 0; 143 rbv_clear = 0x00; 144 gIER = vIER; 145 gIFR = vIFR; 146 gBufA = vBufA; 147 gBufB = vBufB; 148 break; 149 default: 150 panic("UNKNOWN VIA TYPE"); 151 } 152 153 printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1); 154 155 printk(KERN_INFO "VIA2 at %p is ", via2); 156 if (rbv_present) { 157 printk("an RBV\n"); 158 } else if (oss_present) { 159 printk("an OSS\n"); 160 } else { 161 printk("a 6522 or clone\n"); 162 } 163 164 #ifdef DEBUG_VIA 165 via_debug_dump(); 166 #endif 167 168 /* 169 * Shut down all IRQ sources, reset the timers, and 170 * kill the timer latch on VIA1. 171 */ 172 173 via1[vIER] = 0x7F; 174 via1[vIFR] = 0x7F; 175 via1[vT1LL] = 0; 176 via1[vT1LH] = 0; 177 via1[vT1CL] = 0; 178 via1[vT1CH] = 0; 179 via1[vT2CL] = 0; 180 via1[vT2CH] = 0; 181 via1[vACR] &= 0x3F; 182 via1[vACR] &= ~0x03; /* disable port A & B latches */ 183 184 /* 185 * SE/30: disable video IRQ 186 * XXX: testing for SE/30 VBL 187 */ 188 189 if (macintosh_config->ident == MAC_MODEL_SE30) { 190 via1[vDirB] |= 0x40; 191 via1[vBufB] |= 0x40; 192 } 193 194 /* 195 * Set the RTC bits to a known state: all lines to outputs and 196 * RTC disabled (yes that's 0 to enable and 1 to disable). 197 */ 198 199 via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData); 200 via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk); 201 202 /* Everything below this point is VIA2/RBV only... */ 203 204 if (oss_present) return; 205 206 #if 1 207 /* Some machines support an alternate IRQ mapping that spreads */ 208 /* Ethernet and Sound out to their own autolevel IRQs and moves */ 209 /* VIA1 to level 6. A/UX uses this mapping and we do too. Note */ 210 /* that the IIfx emulates this alternate mapping using the OSS. */ 211 212 switch(macintosh_config->ident) { 213 case MAC_MODEL_P475: 214 case MAC_MODEL_P475F: 215 case MAC_MODEL_P575: 216 case MAC_MODEL_Q605: 217 case MAC_MODEL_Q605_ACC: 218 case MAC_MODEL_C610: 219 case MAC_MODEL_Q610: 220 case MAC_MODEL_Q630: 221 case MAC_MODEL_C650: 222 case MAC_MODEL_Q650: 223 case MAC_MODEL_Q700: 224 case MAC_MODEL_Q800: 225 case MAC_MODEL_Q900: 226 case MAC_MODEL_Q950: 227 via_alt_mapping = 1; 228 via1[vDirB] |= 0x40; 229 via1[vBufB] &= ~0x40; 230 break; 231 default: 232 via_alt_mapping = 0; 233 break; 234 } 235 #else 236 via_alt_mapping = 0; 237 #endif 238 239 /* 240 * Now initialize VIA2. For RBV we just kill all interrupts; 241 * for a regular VIA we also reset the timers and stuff. 242 */ 243 244 via2[gIER] = 0x7F; 245 via2[gIFR] = 0x7F | rbv_clear; 246 if (!rbv_present) { 247 via2[vT1LL] = 0; 248 via2[vT1LH] = 0; 249 via2[vT1CL] = 0; 250 via2[vT1CH] = 0; 251 via2[vT2CL] = 0; 252 via2[vT2CH] = 0; 253 via2[vACR] &= 0x3F; 254 via2[vACR] &= ~0x03; /* disable port A & B latches */ 255 } 256 257 /* 258 * Set vPCR for SCSI interrupts (but not on RBV) 259 */ 260 if (!rbv_present) { 261 if (macintosh_config->scsi_type == MAC_SCSI_OLD) { 262 /* CB2 (IRQ) indep. input, positive edge */ 263 /* CA2 (DRQ) indep. input, positive edge */ 264 via2[vPCR] = 0x66; 265 } else { 266 /* CB2 (IRQ) indep. input, negative edge */ 267 /* CA2 (DRQ) indep. input, negative edge */ 268 via2[vPCR] = 0x22; 269 } 270 } 271 } 272 273 /* 274 * Start the 100 Hz clock 275 */ 276 277 void __init via_init_clock(irq_handler_t func) 278 { 279 via1[vACR] |= 0x40; 280 via1[vT1LL] = MAC_CLOCK_LOW; 281 via1[vT1LH] = MAC_CLOCK_HIGH; 282 via1[vT1CL] = MAC_CLOCK_LOW; 283 via1[vT1CH] = MAC_CLOCK_HIGH; 284 285 request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func); 286 } 287 288 /* 289 * Register the interrupt dispatchers for VIA or RBV machines only. 290 */ 291 292 void __init via_register_interrupts(void) 293 { 294 if (via_alt_mapping) { 295 request_irq(IRQ_AUTO_1, via1_irq, 296 IRQ_FLG_LOCK|IRQ_FLG_FAST, "software", 297 (void *) via1); 298 request_irq(IRQ_AUTO_6, via1_irq, 299 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1", 300 (void *) via1); 301 } else { 302 request_irq(IRQ_AUTO_1, via1_irq, 303 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1", 304 (void *) via1); 305 } 306 request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, 307 "via2", (void *) via2); 308 if (!psc_present) { 309 request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK, 310 "scc", mac_scc_dispatch); 311 } 312 request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, 313 "nubus", (void *) via2); 314 } 315 316 /* 317 * Debugging dump, used in various places to see what's going on. 318 */ 319 320 void via_debug_dump(void) 321 { 322 printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", 323 (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]); 324 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", 325 (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]); 326 if (oss_present) { 327 printk(KERN_DEBUG "VIA2: <OSS>\n"); 328 } else if (rbv_present) { 329 printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n", 330 (uint) via2[rIFR], (uint) via2[rIER]); 331 printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n", 332 (uint) via2[rSIFR], (uint) via2[rSIER]); 333 } else { 334 printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", 335 (uint) via2[vDirA], (uint) via2[vDirB], 336 (uint) via2[vACR]); 337 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", 338 (uint) via2[vPCR], 339 (uint) via2[vIFR], (uint) via2[vIER]); 340 } 341 } 342 343 /* 344 * This is always executed with interrupts disabled. 345 * 346 * TBI: get time offset between scheduling timer ticks 347 */ 348 349 unsigned long mac_gettimeoffset (void) 350 { 351 unsigned long ticks, offset = 0; 352 353 /* read VIA1 timer 2 current value */ 354 ticks = via1[vT1CL] | (via1[vT1CH] << 8); 355 /* The probability of underflow is less than 2% */ 356 if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50) 357 /* Check for pending timer interrupt in VIA1 IFR */ 358 if (via1[vIFR] & 0x40) offset = TICK_SIZE; 359 360 ticks = MAC_CLOCK_TICK - ticks; 361 ticks = ticks * 10000L / MAC_CLOCK_TICK; 362 363 return ticks + offset; 364 } 365 366 /* 367 * Flush the L2 cache on Macs that have it by flipping 368 * the system into 24-bit mode for an instant. 369 */ 370 371 void via_flush_cache(void) 372 { 373 via2[gBufB] &= ~VIA2B_vMode32; 374 via2[gBufB] |= VIA2B_vMode32; 375 } 376 377 /* 378 * Return the status of the L2 cache on a IIci 379 */ 380 381 int via_get_cache_disable(void) 382 { 383 /* Safeguard against being called accidentally */ 384 if (!via2) { 385 printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n"); 386 return 1; 387 } 388 389 return (int) via2[gBufB] & VIA2B_vCDis; 390 } 391 392 /* 393 * Initialize VIA2 for Nubus access 394 */ 395 396 void __init via_nubus_init(void) 397 { 398 /* unlock nubus transactions */ 399 400 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 401 (macintosh_config->adb_type != MAC_ADB_PB2)) { 402 /* set the line to be an output on non-RBV machines */ 403 if (!rbv_present) 404 via2[vDirB] |= 0x02; 405 406 /* this seems to be an ADB bit on PMU machines */ 407 /* according to MkLinux. -- jmt */ 408 via2[gBufB] |= 0x02; 409 } 410 411 /* Disable all the slot interrupts (where possible). */ 412 413 switch (macintosh_config->via_type) { 414 case MAC_VIA_II: 415 /* Just make the port A lines inputs. */ 416 switch(macintosh_config->ident) { 417 case MAC_MODEL_II: 418 case MAC_MODEL_IIX: 419 case MAC_MODEL_IICX: 420 case MAC_MODEL_SE30: 421 /* The top two bits are RAM size outputs. */ 422 via2[vDirA] &= 0xC0; 423 break; 424 default: 425 via2[vDirA] &= 0x80; 426 } 427 break; 428 case MAC_VIA_IIci: 429 /* RBV. Disable all the slot interrupts. SIER works like IER. */ 430 via2[rSIER] = 0x7F; 431 break; 432 case MAC_VIA_QUADRA: 433 /* Disable the inactive slot interrupts by making those lines outputs. */ 434 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 435 (macintosh_config->adb_type != MAC_ADB_PB2)) { 436 via2[vBufA] |= 0x7F; 437 via2[vDirA] |= 0x7F; 438 } 439 break; 440 } 441 } 442 443 /* 444 * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's 445 * via6522.c :-), disable/pending masks added. 446 */ 447 448 irqreturn_t via1_irq(int irq, void *dev_id) 449 { 450 int irq_num; 451 unsigned char irq_bit, events; 452 453 events = via1[vIFR] & via1[vIER] & 0x7F; 454 if (!events) 455 return IRQ_NONE; 456 457 irq_num = VIA1_SOURCE_BASE; 458 irq_bit = 1; 459 do { 460 if (events & irq_bit) { 461 via1[vIFR] = irq_bit; 462 m68k_handle_int(irq_num); 463 } 464 ++irq_num; 465 irq_bit <<= 1; 466 } while (events >= irq_bit); 467 468 #if 0 /* freakin' pmu is doing weird stuff */ 469 if (!oss_present) { 470 /* This (still) seems to be necessary to get IDE 471 working. However, if you enable VBL interrupts, 472 you're screwed... */ 473 /* FIXME: should we check the SLOTIRQ bit before 474 pulling this stunt? */ 475 /* No, it won't be set. that's why we're doing this. */ 476 via_irq_disable(IRQ_MAC_NUBUS); 477 via_irq_clear(IRQ_MAC_NUBUS); 478 m68k_handle_int(IRQ_MAC_NUBUS); 479 via_irq_enable(IRQ_MAC_NUBUS); 480 } 481 #endif 482 return IRQ_HANDLED; 483 } 484 485 irqreturn_t via2_irq(int irq, void *dev_id) 486 { 487 int irq_num; 488 unsigned char irq_bit, events; 489 490 events = via2[gIFR] & via2[gIER] & 0x7F; 491 if (!events) 492 return IRQ_NONE; 493 494 irq_num = VIA2_SOURCE_BASE; 495 irq_bit = 1; 496 do { 497 if (events & irq_bit) { 498 via2[gIFR] = irq_bit | rbv_clear; 499 m68k_handle_int(irq_num); 500 } 501 ++irq_num; 502 irq_bit <<= 1; 503 } while (events >= irq_bit); 504 return IRQ_HANDLED; 505 } 506 507 /* 508 * Dispatch Nubus interrupts. We are called as a secondary dispatch by the 509 * VIA2 dispatcher as a fast interrupt handler. 510 */ 511 512 irqreturn_t via_nubus_irq(int irq, void *dev_id) 513 { 514 int slot_irq; 515 unsigned char slot_bit, events; 516 517 events = ~via2[gBufA] & 0x7F; 518 if (rbv_present) 519 events &= via2[rSIER]; 520 else 521 events &= ~via2[vDirA]; 522 if (!events) 523 return IRQ_NONE; 524 525 do { 526 slot_irq = IRQ_NUBUS_F; 527 slot_bit = 0x40; 528 do { 529 if (events & slot_bit) { 530 events &= ~slot_bit; 531 m68k_handle_int(slot_irq); 532 } 533 --slot_irq; 534 slot_bit >>= 1; 535 } while (events); 536 537 /* clear the CA1 interrupt and make certain there's no more. */ 538 via2[gIFR] = 0x02 | rbv_clear; 539 events = ~via2[gBufA] & 0x7F; 540 if (rbv_present) 541 events &= via2[rSIER]; 542 else 543 events &= ~via2[vDirA]; 544 } while (events); 545 return IRQ_HANDLED; 546 } 547 548 void via_irq_enable(int irq) { 549 int irq_src = IRQ_SRC(irq); 550 int irq_idx = IRQ_IDX(irq); 551 552 #ifdef DEBUG_IRQUSE 553 printk(KERN_DEBUG "via_irq_enable(%d)\n", irq); 554 #endif 555 556 if (irq_src == 1) { 557 via1[vIER] = IER_SET_BIT(irq_idx); 558 } else if (irq_src == 2) { 559 if (irq != IRQ_MAC_NUBUS || nubus_disabled == 0) 560 via2[gIER] = IER_SET_BIT(irq_idx); 561 } else if (irq_src == 7) { 562 switch (macintosh_config->via_type) { 563 case MAC_VIA_II: 564 nubus_disabled &= ~(1 << irq_idx); 565 /* Enable the CA1 interrupt when no slot is disabled. */ 566 if (!nubus_disabled) 567 via2[gIER] = IER_SET_BIT(1); 568 break; 569 case MAC_VIA_IIci: 570 /* On RBV, enable the slot interrupt. 571 * SIER works like IER. 572 */ 573 via2[rSIER] = IER_SET_BIT(irq_idx); 574 break; 575 case MAC_VIA_QUADRA: 576 /* Make the port A line an input to enable the slot irq. 577 * But not on PowerBooks, that's ADB. 578 */ 579 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 580 (macintosh_config->adb_type != MAC_ADB_PB2)) 581 via2[vDirA] &= ~(1 << irq_idx); 582 break; 583 } 584 } 585 } 586 587 void via_irq_disable(int irq) { 588 int irq_src = IRQ_SRC(irq); 589 int irq_idx = IRQ_IDX(irq); 590 591 #ifdef DEBUG_IRQUSE 592 printk(KERN_DEBUG "via_irq_disable(%d)\n", irq); 593 #endif 594 595 if (irq_src == 1) { 596 via1[vIER] = IER_CLR_BIT(irq_idx); 597 } else if (irq_src == 2) { 598 via2[gIER] = IER_CLR_BIT(irq_idx); 599 } else if (irq_src == 7) { 600 switch (macintosh_config->via_type) { 601 case MAC_VIA_II: 602 nubus_disabled |= 1 << irq_idx; 603 if (nubus_disabled) 604 via2[gIER] = IER_CLR_BIT(1); 605 break; 606 case MAC_VIA_IIci: 607 via2[rSIER] = IER_CLR_BIT(irq_idx); 608 break; 609 case MAC_VIA_QUADRA: 610 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 611 (macintosh_config->adb_type != MAC_ADB_PB2)) 612 via2[vDirA] |= 1 << irq_idx; 613 break; 614 } 615 } 616 } 617 618 void via_irq_clear(int irq) { 619 int irq_src = IRQ_SRC(irq); 620 int irq_idx = IRQ_IDX(irq); 621 int irq_bit = 1 << irq_idx; 622 623 if (irq_src == 1) { 624 via1[vIFR] = irq_bit; 625 } else if (irq_src == 2) { 626 via2[gIFR] = irq_bit | rbv_clear; 627 } else if (irq_src == 7) { 628 /* FIXME: There is no way to clear an individual nubus slot 629 * IRQ flag, other than getting the device to do it. 630 */ 631 } 632 } 633 634 /* 635 * Returns nonzero if an interrupt is pending on the given 636 * VIA/IRQ combination. 637 */ 638 639 int via_irq_pending(int irq) 640 { 641 int irq_src = IRQ_SRC(irq); 642 int irq_idx = IRQ_IDX(irq); 643 int irq_bit = 1 << irq_idx; 644 645 if (irq_src == 1) { 646 return via1[vIFR] & irq_bit; 647 } else if (irq_src == 2) { 648 return via2[gIFR] & irq_bit; 649 } else if (irq_src == 7) { 650 /* Always 0 for MAC_VIA_QUADRA if the slot irq is disabled. */ 651 return ~via2[gBufA] & irq_bit; 652 } 653 return 0; 654 } 655