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