1 /* 2 * 6522 Versatile Interface Adapter (VIA) 3 * 4 * There are two of these on the Mac II. Some IRQs 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/module.h> 31 32 #include <asm/bootinfo.h> 33 #include <asm/macintosh.h> 34 #include <asm/macints.h> 35 #include <asm/mac_via.h> 36 #include <asm/mac_psc.h> 37 #include <asm/mac_oss.h> 38 39 volatile __u8 *via1, *via2; 40 int rbv_present; 41 int via_alt_mapping; 42 EXPORT_SYMBOL(via_alt_mapping); 43 static __u8 rbv_clear; 44 45 /* 46 * Globals for accessing the VIA chip registers without having to 47 * check if we're hitting a real VIA or an RBV. Normally you could 48 * just hit the combined register (ie, vIER|rIER) but that seems to 49 * break on AV Macs...probably because they actually decode more than 50 * eight address bits. Why can't Apple engineers at least be 51 * _consistently_ lazy? - 1999-05-21 (jmt) 52 */ 53 54 static int gIER,gIFR,gBufA,gBufB; 55 56 /* 57 * Timer defs. 58 */ 59 60 #define TICK_SIZE 10000 61 #define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */ 62 #define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF) 63 #define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8) 64 65 /* To disable a NuBus slot on Quadras we make that slot IRQ line an output set 66 * high. On RBV we just use the slot interrupt enable register. On Macs with 67 * genuine VIA chips we must use nubus_disabled to keep track of disabled slot 68 * interrupts. When any slot IRQ is disabled we mask the (edge triggered) CA1 69 * or "SLOTS" interrupt. When no slot is disabled, we unmask the CA1 interrupt. 70 * So, on genuine VIAs, having more than one NuBus IRQ can mean trouble, 71 * because closing one of those drivers can mask all of the NuBus interrupts. 72 * Also, since we can't mask the unregistered slot IRQs on genuine VIAs, it's 73 * possible to get interrupts from cards that MacOS or the ROM has configured 74 * but we have not. FWIW, "Designing Cards and Drivers for Macintosh II and 75 * Macintosh SE", page 9-8, says, a slot IRQ with no driver would crash MacOS. 76 */ 77 static u8 nubus_disabled; 78 79 void via_debug_dump(void); 80 irqreturn_t via1_irq(int, void *); 81 irqreturn_t via2_irq(int, void *); 82 irqreturn_t via_nubus_irq(int, void *); 83 void via_irq_enable(int irq); 84 void via_irq_disable(int irq); 85 void via_irq_clear(int irq); 86 87 extern irqreturn_t mac_scc_dispatch(int, void *); 88 89 /* 90 * Initialize the VIAs 91 * 92 * First we figure out where they actually _are_ as well as what type of 93 * VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.) 94 * Then we pretty much clear them out and disable all IRQ sources. 95 * 96 * Note: the OSS is actually "detected" here and not in oss_init(). It just 97 * seems more logical to do it here since via_init() needs to know 98 * these things anyways. 99 */ 100 101 void __init via_init(void) 102 { 103 switch(macintosh_config->via_type) { 104 105 /* IIci, IIsi, IIvx, IIvi (P6xx), LC series */ 106 107 case MAC_VIA_IIci: 108 via1 = (void *) VIA1_BASE; 109 if (macintosh_config->ident == MAC_MODEL_IIFX) { 110 via2 = NULL; 111 rbv_present = 0; 112 oss_present = 1; 113 } else { 114 via2 = (void *) RBV_BASE; 115 rbv_present = 1; 116 oss_present = 0; 117 } 118 if (macintosh_config->ident == MAC_MODEL_LCIII) { 119 rbv_clear = 0x00; 120 } else { 121 /* on most RBVs (& unlike the VIAs), you */ 122 /* need to set bit 7 when you write to IFR */ 123 /* in order for your clear to occur. */ 124 rbv_clear = 0x80; 125 } 126 gIER = rIER; 127 gIFR = rIFR; 128 gBufA = rSIFR; 129 gBufB = rBufB; 130 break; 131 132 /* Quadra and early MacIIs agree on the VIA locations */ 133 134 case MAC_VIA_QUADRA: 135 case MAC_VIA_II: 136 via1 = (void *) VIA1_BASE; 137 via2 = (void *) VIA2_BASE; 138 rbv_present = 0; 139 oss_present = 0; 140 rbv_clear = 0x00; 141 gIER = vIER; 142 gIFR = vIFR; 143 gBufA = vBufA; 144 gBufB = vBufB; 145 break; 146 default: 147 panic("UNKNOWN VIA TYPE"); 148 } 149 150 printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1); 151 152 printk(KERN_INFO "VIA2 at %p is ", via2); 153 if (rbv_present) { 154 printk("an RBV\n"); 155 } else if (oss_present) { 156 printk("an OSS\n"); 157 } else { 158 printk("a 6522 or clone\n"); 159 } 160 161 #ifdef DEBUG_VIA 162 via_debug_dump(); 163 #endif 164 165 /* 166 * Shut down all IRQ sources, reset the timers, and 167 * kill the timer latch on VIA1. 168 */ 169 170 via1[vIER] = 0x7F; 171 via1[vIFR] = 0x7F; 172 via1[vT1LL] = 0; 173 via1[vT1LH] = 0; 174 via1[vT1CL] = 0; 175 via1[vT1CH] = 0; 176 via1[vT2CL] = 0; 177 via1[vT2CH] = 0; 178 via1[vACR] &= ~0xC0; /* setup T1 timer with no PB7 output */ 179 via1[vACR] &= ~0x03; /* disable port A & B latches */ 180 181 /* 182 * SE/30: disable video IRQ 183 * XXX: testing for SE/30 VBL 184 */ 185 186 if (macintosh_config->ident == MAC_MODEL_SE30) { 187 via1[vDirB] |= 0x40; 188 via1[vBufB] |= 0x40; 189 } 190 191 /* 192 * Set the RTC bits to a known state: all lines to outputs and 193 * RTC disabled (yes that's 0 to enable and 1 to disable). 194 */ 195 196 via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData); 197 via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk); 198 199 /* Everything below this point is VIA2/RBV only... */ 200 201 if (oss_present) 202 return; 203 204 /* Some machines support an alternate IRQ mapping that spreads */ 205 /* Ethernet and Sound out to their own autolevel IRQs and moves */ 206 /* VIA1 to level 6. A/UX uses this mapping and we do too. Note */ 207 /* that the IIfx emulates this alternate mapping using the OSS. */ 208 209 via_alt_mapping = 0; 210 if (macintosh_config->via_type == MAC_VIA_QUADRA) 211 switch (macintosh_config->ident) { 212 case MAC_MODEL_C660: 213 case MAC_MODEL_Q840: 214 /* not applicable */ 215 break; 216 case MAC_MODEL_P588: 217 case MAC_MODEL_TV: 218 case MAC_MODEL_PB140: 219 case MAC_MODEL_PB145: 220 case MAC_MODEL_PB160: 221 case MAC_MODEL_PB165: 222 case MAC_MODEL_PB165C: 223 case MAC_MODEL_PB170: 224 case MAC_MODEL_PB180: 225 case MAC_MODEL_PB180C: 226 case MAC_MODEL_PB190: 227 case MAC_MODEL_PB520: 228 /* not yet tested */ 229 break; 230 default: 231 via_alt_mapping = 1; 232 via1[vDirB] |= 0x40; 233 via1[vBufB] &= ~0x40; 234 break; 235 } 236 237 /* 238 * Now initialize VIA2. For RBV we just kill all interrupts; 239 * for a regular VIA we also reset the timers and stuff. 240 */ 241 242 via2[gIER] = 0x7F; 243 via2[gIFR] = 0x7F | rbv_clear; 244 if (!rbv_present) { 245 via2[vT1LL] = 0; 246 via2[vT1LH] = 0; 247 via2[vT1CL] = 0; 248 via2[vT1CH] = 0; 249 via2[vT2CL] = 0; 250 via2[vT2CH] = 0; 251 via2[vACR] &= ~0xC0; /* setup T1 timer with no PB7 output */ 252 via2[vACR] &= ~0x03; /* disable port A & B latches */ 253 } 254 255 /* 256 * Set vPCR for control line interrupts (but not on RBV) 257 */ 258 if (!rbv_present) { 259 /* For all VIA types, CA1 (SLOTS IRQ) and CB1 (ASC IRQ) 260 * are made negative edge triggered here. 261 */ 262 if (macintosh_config->scsi_type == MAC_SCSI_OLD) { 263 /* CB2 (IRQ) indep. input, positive edge */ 264 /* CA2 (DRQ) indep. input, positive edge */ 265 via2[vPCR] = 0x66; 266 } else { 267 /* CB2 (IRQ) indep. input, negative edge */ 268 /* CA2 (DRQ) indep. input, negative edge */ 269 via2[vPCR] = 0x22; 270 } 271 } 272 } 273 274 /* 275 * Start the 100 Hz clock 276 */ 277 278 void __init via_init_clock(irq_handler_t func) 279 { 280 via1[vACR] |= 0x40; 281 via1[vT1LL] = MAC_CLOCK_LOW; 282 via1[vT1LH] = MAC_CLOCK_HIGH; 283 via1[vT1CL] = MAC_CLOCK_LOW; 284 via1[vT1CH] = MAC_CLOCK_HIGH; 285 286 if (request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func)) 287 pr_err("Couldn't register %s interrupt\n", "timer"); 288 } 289 290 /* 291 * Register the interrupt dispatchers for VIA or RBV machines only. 292 */ 293 294 void __init via_register_interrupts(void) 295 { 296 if (via_alt_mapping) { 297 if (request_irq(IRQ_AUTO_1, via1_irq, 298 IRQ_FLG_LOCK|IRQ_FLG_FAST, "software", 299 (void *) via1)) 300 pr_err("Couldn't register %s interrupt\n", "software"); 301 if (request_irq(IRQ_AUTO_6, via1_irq, 302 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1", 303 (void *) via1)) 304 pr_err("Couldn't register %s interrupt\n", "via1"); 305 } else { 306 if (request_irq(IRQ_AUTO_1, via1_irq, 307 IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1", 308 (void *) via1)) 309 pr_err("Couldn't register %s interrupt\n", "via1"); 310 } 311 if (request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, 312 "via2", (void *) via2)) 313 pr_err("Couldn't register %s interrupt\n", "via2"); 314 if (!psc_present) { 315 if (request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK, 316 "scc", mac_scc_dispatch)) 317 pr_err("Couldn't register %s interrupt\n", "scc"); 318 } 319 if (request_irq(IRQ_MAC_NUBUS, via_nubus_irq, 320 IRQ_FLG_LOCK|IRQ_FLG_FAST, "nubus", (void *) via2)) 321 pr_err("Couldn't register %s interrupt\n", "nubus"); 322 } 323 324 /* 325 * Debugging dump, used in various places to see what's going on. 326 */ 327 328 void via_debug_dump(void) 329 { 330 printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", 331 (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]); 332 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", 333 (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]); 334 if (oss_present) { 335 printk(KERN_DEBUG "VIA2: <OSS>\n"); 336 } else if (rbv_present) { 337 printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n", 338 (uint) via2[rIFR], (uint) via2[rIER]); 339 printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n", 340 (uint) via2[rSIFR], (uint) via2[rSIER]); 341 } else { 342 printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", 343 (uint) via2[vDirA], (uint) via2[vDirB], 344 (uint) via2[vACR]); 345 printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", 346 (uint) via2[vPCR], 347 (uint) via2[vIFR], (uint) via2[vIER]); 348 } 349 } 350 351 /* 352 * This is always executed with interrupts disabled. 353 * 354 * TBI: get time offset between scheduling timer ticks 355 */ 356 357 unsigned long mac_gettimeoffset (void) 358 { 359 unsigned long ticks, offset = 0; 360 361 /* read VIA1 timer 2 current value */ 362 ticks = via1[vT1CL] | (via1[vT1CH] << 8); 363 /* The probability of underflow is less than 2% */ 364 if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50) 365 /* Check for pending timer interrupt in VIA1 IFR */ 366 if (via1[vIFR] & 0x40) offset = TICK_SIZE; 367 368 ticks = MAC_CLOCK_TICK - ticks; 369 ticks = ticks * 10000L / MAC_CLOCK_TICK; 370 371 return ticks + offset; 372 } 373 374 /* 375 * Flush the L2 cache on Macs that have it by flipping 376 * the system into 24-bit mode for an instant. 377 */ 378 379 void via_flush_cache(void) 380 { 381 via2[gBufB] &= ~VIA2B_vMode32; 382 via2[gBufB] |= VIA2B_vMode32; 383 } 384 385 /* 386 * Return the status of the L2 cache on a IIci 387 */ 388 389 int via_get_cache_disable(void) 390 { 391 /* Safeguard against being called accidentally */ 392 if (!via2) { 393 printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n"); 394 return 1; 395 } 396 397 return (int) via2[gBufB] & VIA2B_vCDis; 398 } 399 400 /* 401 * Initialize VIA2 for Nubus access 402 */ 403 404 void __init via_nubus_init(void) 405 { 406 /* unlock nubus transactions */ 407 408 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 409 (macintosh_config->adb_type != MAC_ADB_PB2)) { 410 /* set the line to be an output on non-RBV machines */ 411 if (!rbv_present) 412 via2[vDirB] |= 0x02; 413 414 /* this seems to be an ADB bit on PMU machines */ 415 /* according to MkLinux. -- jmt */ 416 via2[gBufB] |= 0x02; 417 } 418 419 /* Disable all the slot interrupts (where possible). */ 420 421 switch (macintosh_config->via_type) { 422 case MAC_VIA_II: 423 /* Just make the port A lines inputs. */ 424 switch(macintosh_config->ident) { 425 case MAC_MODEL_II: 426 case MAC_MODEL_IIX: 427 case MAC_MODEL_IICX: 428 case MAC_MODEL_SE30: 429 /* The top two bits are RAM size outputs. */ 430 via2[vDirA] &= 0xC0; 431 break; 432 default: 433 via2[vDirA] &= 0x80; 434 } 435 break; 436 case MAC_VIA_IIci: 437 /* RBV. Disable all the slot interrupts. SIER works like IER. */ 438 via2[rSIER] = 0x7F; 439 break; 440 case MAC_VIA_QUADRA: 441 /* Disable the inactive slot interrupts by making those lines outputs. */ 442 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 443 (macintosh_config->adb_type != MAC_ADB_PB2)) { 444 via2[vBufA] |= 0x7F; 445 via2[vDirA] |= 0x7F; 446 } 447 break; 448 } 449 } 450 451 /* 452 * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's 453 * via6522.c :-), disable/pending masks added. 454 */ 455 456 irqreturn_t via1_irq(int irq, void *dev_id) 457 { 458 int irq_num; 459 unsigned char irq_bit, events; 460 461 events = via1[vIFR] & via1[vIER] & 0x7F; 462 if (!events) 463 return IRQ_NONE; 464 465 irq_num = VIA1_SOURCE_BASE; 466 irq_bit = 1; 467 do { 468 if (events & irq_bit) { 469 via1[vIFR] = irq_bit; 470 m68k_handle_int(irq_num); 471 } 472 ++irq_num; 473 irq_bit <<= 1; 474 } while (events >= irq_bit); 475 return IRQ_HANDLED; 476 } 477 478 irqreturn_t via2_irq(int irq, void *dev_id) 479 { 480 int irq_num; 481 unsigned char irq_bit, events; 482 483 events = via2[gIFR] & via2[gIER] & 0x7F; 484 if (!events) 485 return IRQ_NONE; 486 487 irq_num = VIA2_SOURCE_BASE; 488 irq_bit = 1; 489 do { 490 if (events & irq_bit) { 491 via2[gIFR] = irq_bit | rbv_clear; 492 m68k_handle_int(irq_num); 493 } 494 ++irq_num; 495 irq_bit <<= 1; 496 } while (events >= irq_bit); 497 return IRQ_HANDLED; 498 } 499 500 /* 501 * Dispatch Nubus interrupts. We are called as a secondary dispatch by the 502 * VIA2 dispatcher as a fast interrupt handler. 503 */ 504 505 irqreturn_t via_nubus_irq(int irq, void *dev_id) 506 { 507 int slot_irq; 508 unsigned char slot_bit, events; 509 510 events = ~via2[gBufA] & 0x7F; 511 if (rbv_present) 512 events &= via2[rSIER]; 513 else 514 events &= ~via2[vDirA]; 515 if (!events) 516 return IRQ_NONE; 517 518 do { 519 slot_irq = IRQ_NUBUS_F; 520 slot_bit = 0x40; 521 do { 522 if (events & slot_bit) { 523 events &= ~slot_bit; 524 m68k_handle_int(slot_irq); 525 } 526 --slot_irq; 527 slot_bit >>= 1; 528 } while (events); 529 530 /* clear the CA1 interrupt and make certain there's no more. */ 531 via2[gIFR] = 0x02 | rbv_clear; 532 events = ~via2[gBufA] & 0x7F; 533 if (rbv_present) 534 events &= via2[rSIER]; 535 else 536 events &= ~via2[vDirA]; 537 } while (events); 538 return IRQ_HANDLED; 539 } 540 541 void via_irq_enable(int irq) { 542 int irq_src = IRQ_SRC(irq); 543 int irq_idx = IRQ_IDX(irq); 544 545 #ifdef DEBUG_IRQUSE 546 printk(KERN_DEBUG "via_irq_enable(%d)\n", irq); 547 #endif 548 549 if (irq_src == 1) { 550 via1[vIER] = IER_SET_BIT(irq_idx); 551 } else if (irq_src == 2) { 552 if (irq != IRQ_MAC_NUBUS || nubus_disabled == 0) 553 via2[gIER] = IER_SET_BIT(irq_idx); 554 } else if (irq_src == 7) { 555 switch (macintosh_config->via_type) { 556 case MAC_VIA_II: 557 nubus_disabled &= ~(1 << irq_idx); 558 /* Enable the CA1 interrupt when no slot is disabled. */ 559 if (!nubus_disabled) 560 via2[gIER] = IER_SET_BIT(1); 561 break; 562 case MAC_VIA_IIci: 563 /* On RBV, enable the slot interrupt. 564 * SIER works like IER. 565 */ 566 via2[rSIER] = IER_SET_BIT(irq_idx); 567 break; 568 case MAC_VIA_QUADRA: 569 /* Make the port A line an input to enable the slot irq. 570 * But not on PowerBooks, that's ADB. 571 */ 572 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 573 (macintosh_config->adb_type != MAC_ADB_PB2)) 574 via2[vDirA] &= ~(1 << irq_idx); 575 break; 576 } 577 } 578 } 579 580 void via_irq_disable(int irq) { 581 int irq_src = IRQ_SRC(irq); 582 int irq_idx = IRQ_IDX(irq); 583 584 #ifdef DEBUG_IRQUSE 585 printk(KERN_DEBUG "via_irq_disable(%d)\n", irq); 586 #endif 587 588 if (irq_src == 1) { 589 via1[vIER] = IER_CLR_BIT(irq_idx); 590 } else if (irq_src == 2) { 591 via2[gIER] = IER_CLR_BIT(irq_idx); 592 } else if (irq_src == 7) { 593 switch (macintosh_config->via_type) { 594 case MAC_VIA_II: 595 nubus_disabled |= 1 << irq_idx; 596 if (nubus_disabled) 597 via2[gIER] = IER_CLR_BIT(1); 598 break; 599 case MAC_VIA_IIci: 600 via2[rSIER] = IER_CLR_BIT(irq_idx); 601 break; 602 case MAC_VIA_QUADRA: 603 if ((macintosh_config->adb_type != MAC_ADB_PB1) && 604 (macintosh_config->adb_type != MAC_ADB_PB2)) 605 via2[vDirA] |= 1 << irq_idx; 606 break; 607 } 608 } 609 } 610 611 void via_irq_clear(int irq) { 612 int irq_src = IRQ_SRC(irq); 613 int irq_idx = IRQ_IDX(irq); 614 int irq_bit = 1 << irq_idx; 615 616 if (irq_src == 1) { 617 via1[vIFR] = irq_bit; 618 } else if (irq_src == 2) { 619 via2[gIFR] = irq_bit | rbv_clear; 620 } else if (irq_src == 7) { 621 /* FIXME: There is no way to clear an individual nubus slot 622 * IRQ flag, other than getting the device to do it. 623 */ 624 } 625 } 626 627 /* 628 * Returns nonzero if an interrupt is pending on the given 629 * VIA/IRQ combination. 630 */ 631 632 int via_irq_pending(int irq) 633 { 634 int irq_src = IRQ_SRC(irq); 635 int irq_idx = IRQ_IDX(irq); 636 int irq_bit = 1 << irq_idx; 637 638 if (irq_src == 1) { 639 return via1[vIFR] & irq_bit; 640 } else if (irq_src == 2) { 641 return via2[gIFR] & irq_bit; 642 } else if (irq_src == 7) { 643 /* Always 0 for MAC_VIA_QUADRA if the slot irq is disabled. */ 644 return ~via2[gBufA] & irq_bit; 645 } 646 return 0; 647 } 648 649 void via1_set_head(int head) 650 { 651 if (head == 0) 652 via1[vBufA] &= ~VIA1A_vHeadSel; 653 else 654 via1[vBufA] |= VIA1A_vHeadSel; 655 } 656 EXPORT_SYMBOL(via1_set_head); 657