/* * 6522 Versatile Interface Adapter (VIA) * * There are two of these on the Mac II. Some IRQs are vectored * via them as are assorted bits and bobs - eg RTC, ADB. * * CSA: Motorola seems to have removed documentation on the 6522 from * their web site; try * http://nerini.drf.com/vectrex/other/text/chips/6522/ * http://www.zymurgy.net/classic/vic20/vicdet1.htm * and * http://193.23.168.87/mikro_laborversuche/via_iobaustein/via6522_1.html * for info. A full-text web search on 6522 AND VIA will probably also * net some usefulness. 20apr1999 * * Additional data is here (the SY6522 was used in the Mac II etc): * http://www.6502.org/documents/datasheets/synertek/synertek_sy6522.pdf * http://www.6502.org/documents/datasheets/synertek/synertek_sy6522_programming_reference.pdf * * PRAM/RTC access algorithms are from the NetBSD RTC toolkit version 1.08b * by Erik Vogan and adapted to Linux by Joshua M. Thompson (funaho@jurai.org) * */ #include #include #include #include #include #include #include #include #include #include #include #include #include volatile __u8 *via1, *via2; int rbv_present; int via_alt_mapping; EXPORT_SYMBOL(via_alt_mapping); static __u8 rbv_clear; /* * Globals for accessing the VIA chip registers without having to * check if we're hitting a real VIA or an RBV. Normally you could * just hit the combined register (ie, vIER|rIER) but that seems to * break on AV Macs...probably because they actually decode more than * eight address bits. Why can't Apple engineers at least be * _consistently_ lazy? - 1999-05-21 (jmt) */ static int gIER,gIFR,gBufA,gBufB; /* * Timer defs. */ #define TICK_SIZE 10000 #define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */ #define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF) #define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8) /* To disable a NuBus slot on Quadras we make that slot IRQ line an output set * high. On RBV we just use the slot interrupt enable register. On Macs with * genuine VIA chips we must use nubus_disabled to keep track of disabled slot * interrupts. When any slot IRQ is disabled we mask the (edge triggered) CA1 * or "SLOTS" interrupt. When no slot is disabled, we unmask the CA1 interrupt. * So, on genuine VIAs, having more than one NuBus IRQ can mean trouble, * because closing one of those drivers can mask all of the NuBus interrupts. * Also, since we can't mask the unregistered slot IRQs on genuine VIAs, it's * possible to get interrupts from cards that MacOS or the ROM has configured * but we have not. FWIW, "Designing Cards and Drivers for Macintosh II and * Macintosh SE", page 9-8, says, a slot IRQ with no driver would crash MacOS. */ static u8 nubus_disabled; void via_debug_dump(void); void via_irq_enable(int irq); void via_irq_disable(int irq); void via_irq_clear(int irq); /* * Initialize the VIAs * * First we figure out where they actually _are_ as well as what type of * VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.) * Then we pretty much clear them out and disable all IRQ sources. * * Note: the OSS is actually "detected" here and not in oss_init(). It just * seems more logical to do it here since via_init() needs to know * these things anyways. */ void __init via_init(void) { switch(macintosh_config->via_type) { /* IIci, IIsi, IIvx, IIvi (P6xx), LC series */ case MAC_VIA_IIci: via1 = (void *) VIA1_BASE; if (macintosh_config->ident == MAC_MODEL_IIFX) { via2 = NULL; rbv_present = 0; oss_present = 1; } else { via2 = (void *) RBV_BASE; rbv_present = 1; oss_present = 0; } if (macintosh_config->ident == MAC_MODEL_LCIII) { rbv_clear = 0x00; } else { /* on most RBVs (& unlike the VIAs), you */ /* need to set bit 7 when you write to IFR */ /* in order for your clear to occur. */ rbv_clear = 0x80; } gIER = rIER; gIFR = rIFR; gBufA = rSIFR; gBufB = rBufB; break; /* Quadra and early MacIIs agree on the VIA locations */ case MAC_VIA_QUADRA: case MAC_VIA_II: via1 = (void *) VIA1_BASE; via2 = (void *) VIA2_BASE; rbv_present = 0; oss_present = 0; rbv_clear = 0x00; gIER = vIER; gIFR = vIFR; gBufA = vBufA; gBufB = vBufB; break; default: panic("UNKNOWN VIA TYPE"); } printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1); printk(KERN_INFO "VIA2 at %p is ", via2); if (rbv_present) { printk("an RBV\n"); } else if (oss_present) { printk("an OSS\n"); } else { printk("a 6522 or clone\n"); } #ifdef DEBUG_VIA via_debug_dump(); #endif /* * Shut down all IRQ sources, reset the timers, and * kill the timer latch on VIA1. */ via1[vIER] = 0x7F; via1[vIFR] = 0x7F; via1[vT1LL] = 0; via1[vT1LH] = 0; via1[vT1CL] = 0; via1[vT1CH] = 0; via1[vT2CL] = 0; via1[vT2CH] = 0; via1[vACR] &= ~0xC0; /* setup T1 timer with no PB7 output */ via1[vACR] &= ~0x03; /* disable port A & B latches */ /* * SE/30: disable video IRQ * XXX: testing for SE/30 VBL */ if (macintosh_config->ident == MAC_MODEL_SE30) { via1[vDirB] |= 0x40; via1[vBufB] |= 0x40; } /* * Set the RTC bits to a known state: all lines to outputs and * RTC disabled (yes that's 0 to enable and 1 to disable). */ via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData); via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk); /* Everything below this point is VIA2/RBV only... */ if (oss_present) return; /* Some machines support an alternate IRQ mapping that spreads */ /* Ethernet and Sound out to their own autolevel IRQs and moves */ /* VIA1 to level 6. A/UX uses this mapping and we do too. Note */ /* that the IIfx emulates this alternate mapping using the OSS. */ via_alt_mapping = 0; if (macintosh_config->via_type == MAC_VIA_QUADRA) switch (macintosh_config->ident) { case MAC_MODEL_C660: case MAC_MODEL_Q840: /* not applicable */ break; case MAC_MODEL_P588: case MAC_MODEL_TV: case MAC_MODEL_PB140: case MAC_MODEL_PB145: case MAC_MODEL_PB160: case MAC_MODEL_PB165: case MAC_MODEL_PB165C: case MAC_MODEL_PB170: case MAC_MODEL_PB180: case MAC_MODEL_PB180C: case MAC_MODEL_PB190: case MAC_MODEL_PB520: /* not yet tested */ break; default: via_alt_mapping = 1; via1[vDirB] |= 0x40; via1[vBufB] &= ~0x40; break; } /* * Now initialize VIA2. For RBV we just kill all interrupts; * for a regular VIA we also reset the timers and stuff. */ via2[gIER] = 0x7F; via2[gIFR] = 0x7F | rbv_clear; if (!rbv_present) { via2[vT1LL] = 0; via2[vT1LH] = 0; via2[vT1CL] = 0; via2[vT1CH] = 0; via2[vT2CL] = 0; via2[vT2CH] = 0; via2[vACR] &= ~0xC0; /* setup T1 timer with no PB7 output */ via2[vACR] &= ~0x03; /* disable port A & B latches */ } /* * Set vPCR for control line interrupts (but not on RBV) */ if (!rbv_present) { /* For all VIA types, CA1 (SLOTS IRQ) and CB1 (ASC IRQ) * are made negative edge triggered here. */ if (macintosh_config->scsi_type == MAC_SCSI_OLD) { /* CB2 (IRQ) indep. input, positive edge */ /* CA2 (DRQ) indep. input, positive edge */ via2[vPCR] = 0x66; } else { /* CB2 (IRQ) indep. input, negative edge */ /* CA2 (DRQ) indep. input, negative edge */ via2[vPCR] = 0x22; } } } /* * Start the 100 Hz clock */ void __init via_init_clock(irq_handler_t func) { via1[vACR] |= 0x40; via1[vT1LL] = MAC_CLOCK_LOW; via1[vT1LH] = MAC_CLOCK_HIGH; via1[vT1CL] = MAC_CLOCK_LOW; via1[vT1CH] = MAC_CLOCK_HIGH; if (request_irq(IRQ_MAC_TIMER_1, func, 0, "timer", func)) pr_err("Couldn't register %s interrupt\n", "timer"); } /* * Debugging dump, used in various places to see what's going on. */ void via_debug_dump(void) { printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]); printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]); if (oss_present) { printk(KERN_DEBUG "VIA2: \n"); } else if (rbv_present) { printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n", (uint) via2[rIFR], (uint) via2[rIER]); printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n", (uint) via2[rSIFR], (uint) via2[rSIER]); } else { printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", (uint) via2[vDirA], (uint) via2[vDirB], (uint) via2[vACR]); printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", (uint) via2[vPCR], (uint) via2[vIFR], (uint) via2[vIER]); } } /* * This is always executed with interrupts disabled. * * TBI: get time offset between scheduling timer ticks */ unsigned long mac_gettimeoffset (void) { unsigned long ticks, offset = 0; /* read VIA1 timer 2 current value */ ticks = via1[vT1CL] | (via1[vT1CH] << 8); /* The probability of underflow is less than 2% */ if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50) /* Check for pending timer interrupt in VIA1 IFR */ if (via1[vIFR] & 0x40) offset = TICK_SIZE; ticks = MAC_CLOCK_TICK - ticks; ticks = ticks * 10000L / MAC_CLOCK_TICK; return ticks + offset; } /* * Flush the L2 cache on Macs that have it by flipping * the system into 24-bit mode for an instant. */ void via_flush_cache(void) { via2[gBufB] &= ~VIA2B_vMode32; via2[gBufB] |= VIA2B_vMode32; } /* * Return the status of the L2 cache on a IIci */ int via_get_cache_disable(void) { /* Safeguard against being called accidentally */ if (!via2) { printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n"); return 1; } return (int) via2[gBufB] & VIA2B_vCDis; } /* * Initialize VIA2 for Nubus access */ void __init via_nubus_init(void) { /* unlock nubus transactions */ if ((macintosh_config->adb_type != MAC_ADB_PB1) && (macintosh_config->adb_type != MAC_ADB_PB2)) { /* set the line to be an output on non-RBV machines */ if (!rbv_present) via2[vDirB] |= 0x02; /* this seems to be an ADB bit on PMU machines */ /* according to MkLinux. -- jmt */ via2[gBufB] |= 0x02; } /* Disable all the slot interrupts (where possible). */ switch (macintosh_config->via_type) { case MAC_VIA_II: /* Just make the port A lines inputs. */ switch(macintosh_config->ident) { case MAC_MODEL_II: case MAC_MODEL_IIX: case MAC_MODEL_IICX: case MAC_MODEL_SE30: /* The top two bits are RAM size outputs. */ via2[vDirA] &= 0xC0; break; default: via2[vDirA] &= 0x80; } break; case MAC_VIA_IIci: /* RBV. Disable all the slot interrupts. SIER works like IER. */ via2[rSIER] = 0x7F; break; case MAC_VIA_QUADRA: /* Disable the inactive slot interrupts by making those lines outputs. */ if ((macintosh_config->adb_type != MAC_ADB_PB1) && (macintosh_config->adb_type != MAC_ADB_PB2)) { via2[vBufA] |= 0x7F; via2[vDirA] |= 0x7F; } break; } } /* * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's * via6522.c :-), disable/pending masks added. */ void via1_irq(unsigned int irq, struct irq_desc *desc) { int irq_num; unsigned char irq_bit, events; events = via1[vIFR] & via1[vIER] & 0x7F; if (!events) return; irq_num = VIA1_SOURCE_BASE; irq_bit = 1; do { if (events & irq_bit) { via1[vIFR] = irq_bit; generic_handle_irq(irq_num); } ++irq_num; irq_bit <<= 1; } while (events >= irq_bit); } static void via2_irq(unsigned int irq, struct irq_desc *desc) { int irq_num; unsigned char irq_bit, events; events = via2[gIFR] & via2[gIER] & 0x7F; if (!events) return; irq_num = VIA2_SOURCE_BASE; irq_bit = 1; do { if (events & irq_bit) { via2[gIFR] = irq_bit | rbv_clear; generic_handle_irq(irq_num); } ++irq_num; irq_bit <<= 1; } while (events >= irq_bit); } /* * Dispatch Nubus interrupts. We are called as a secondary dispatch by the * VIA2 dispatcher as a fast interrupt handler. */ void via_nubus_irq(unsigned int irq, struct irq_desc *desc) { int slot_irq; unsigned char slot_bit, events; events = ~via2[gBufA] & 0x7F; if (rbv_present) events &= via2[rSIER]; else events &= ~via2[vDirA]; if (!events) return; do { slot_irq = IRQ_NUBUS_F; slot_bit = 0x40; do { if (events & slot_bit) { events &= ~slot_bit; generic_handle_irq(slot_irq); } --slot_irq; slot_bit >>= 1; } while (events); /* clear the CA1 interrupt and make certain there's no more. */ via2[gIFR] = 0x02 | rbv_clear; events = ~via2[gBufA] & 0x7F; if (rbv_present) events &= via2[rSIER]; else events &= ~via2[vDirA]; } while (events); } /* * Register the interrupt dispatchers for VIA or RBV machines only. */ void __init via_register_interrupts(void) { if (via_alt_mapping) { /* software interrupt */ irq_set_chained_handler(IRQ_AUTO_1, via1_irq); /* via1 interrupt */ irq_set_chained_handler(IRQ_AUTO_6, via1_irq); } else { irq_set_chained_handler(IRQ_AUTO_1, via1_irq); } irq_set_chained_handler(IRQ_AUTO_2, via2_irq); irq_set_chained_handler(IRQ_MAC_NUBUS, via_nubus_irq); } void via_irq_enable(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); #ifdef DEBUG_IRQUSE printk(KERN_DEBUG "via_irq_enable(%d)\n", irq); #endif if (irq_src == 1) { via1[vIER] = IER_SET_BIT(irq_idx); } else if (irq_src == 2) { if (irq != IRQ_MAC_NUBUS || nubus_disabled == 0) via2[gIER] = IER_SET_BIT(irq_idx); } else if (irq_src == 7) { switch (macintosh_config->via_type) { case MAC_VIA_II: nubus_disabled &= ~(1 << irq_idx); /* Enable the CA1 interrupt when no slot is disabled. */ if (!nubus_disabled) via2[gIER] = IER_SET_BIT(1); break; case MAC_VIA_IIci: /* On RBV, enable the slot interrupt. * SIER works like IER. */ via2[rSIER] = IER_SET_BIT(irq_idx); break; case MAC_VIA_QUADRA: /* Make the port A line an input to enable the slot irq. * But not on PowerBooks, that's ADB. */ if ((macintosh_config->adb_type != MAC_ADB_PB1) && (macintosh_config->adb_type != MAC_ADB_PB2)) via2[vDirA] &= ~(1 << irq_idx); break; } } } void via_irq_disable(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); #ifdef DEBUG_IRQUSE printk(KERN_DEBUG "via_irq_disable(%d)\n", irq); #endif if (irq_src == 1) { via1[vIER] = IER_CLR_BIT(irq_idx); } else if (irq_src == 2) { via2[gIER] = IER_CLR_BIT(irq_idx); } else if (irq_src == 7) { switch (macintosh_config->via_type) { case MAC_VIA_II: nubus_disabled |= 1 << irq_idx; if (nubus_disabled) via2[gIER] = IER_CLR_BIT(1); break; case MAC_VIA_IIci: via2[rSIER] = IER_CLR_BIT(irq_idx); break; case MAC_VIA_QUADRA: if ((macintosh_config->adb_type != MAC_ADB_PB1) && (macintosh_config->adb_type != MAC_ADB_PB2)) via2[vDirA] |= 1 << irq_idx; break; } } } void via_irq_clear(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); int irq_bit = 1 << irq_idx; if (irq_src == 1) { via1[vIFR] = irq_bit; } else if (irq_src == 2) { via2[gIFR] = irq_bit | rbv_clear; } else if (irq_src == 7) { /* FIXME: There is no way to clear an individual nubus slot * IRQ flag, other than getting the device to do it. */ } } /* * Returns nonzero if an interrupt is pending on the given * VIA/IRQ combination. */ int via_irq_pending(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); int irq_bit = 1 << irq_idx; if (irq_src == 1) { return via1[vIFR] & irq_bit; } else if (irq_src == 2) { return via2[gIFR] & irq_bit; } else if (irq_src == 7) { /* Always 0 for MAC_VIA_QUADRA if the slot irq is disabled. */ return ~via2[gBufA] & irq_bit; } return 0; } void via1_set_head(int head) { if (head == 0) via1[vBufA] &= ~VIA1A_vHeadSel; else via1[vBufA] |= VIA1A_vHeadSel; } EXPORT_SYMBOL(via1_set_head);