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