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