/* * 6522 Versatile Interface Adapter (VIA) * * There are two of these on the Mac II. Some IRQ's 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 * * 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 volatile __u8 *via1, *via2; #if 0 /* See note in mac_via.h about how this is possibly not useful */ volatile long *via_memory_bogon=(long *)&via_memory_bogon; #endif int rbv_present,via_alt_mapping; __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 * _consistantly_ 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) static int nubus_active; void via_debug_dump(void); void via1_irq(int, void *, struct pt_regs *); void via2_irq(int, void *, struct pt_regs *); void via_nubus_irq(int, void *, struct pt_regs *); void via_irq_enable(int irq); void via_irq_disable(int irq); void via_irq_clear(int irq); extern void mac_bang(int, void *, struct pt_regs *); extern void mac_SCC_handler(int, void *, struct pt_regs *); extern int console_loglevel; extern int oss_present; /* * 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("VIA1 at %p is a 6522 or clone\n", via1); printk("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] &= 0x3F; /* * 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; #if 1 /* 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. */ switch(macintosh_config->ident) { case MAC_MODEL_C610: case MAC_MODEL_Q610: case MAC_MODEL_C650: case MAC_MODEL_Q650: case MAC_MODEL_Q700: case MAC_MODEL_Q800: case MAC_MODEL_Q900: case MAC_MODEL_Q950: via_alt_mapping = 1; via1[vDirB] |= 0x40; via1[vBufB] &= ~0x40; break; default: via_alt_mapping = 0; break; } #else /* The alernate IRQ mapping seems to just not work. Anyone with a */ /* supported machine is welcome to take a stab at fixing it. It */ /* _should_ work on the following Quadras: 610,650,700,800,900,950 */ /* - 1999-06-12 (jmt) */ via_alt_mapping = 0; #endif /* * 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] &= 0x3F; } } /* * Start the 100 Hz clock */ void __init via_init_clock(void (*func)(int, void *, struct pt_regs *)) { via1[vACR] |= 0x40; via1[vT1LL] = MAC_CLOCK_LOW; via1[vT1LH] = MAC_CLOCK_HIGH; via1[vT1CL] = MAC_CLOCK_LOW; via1[vT1CH] = MAC_CLOCK_HIGH; request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func); } /* * Register the interrupt dispatchers for VIA or RBV machines only. */ void __init via_register_interrupts(void) { if (via_alt_mapping) { request_irq(IRQ_AUTO_1, via1_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, "Software IRQ", (void *) via1); request_irq(IRQ_AUTO_6, via1_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, "VIA1 Dispatch", (void *) via1); } else { request_irq(IRQ_AUTO_1, via1_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, "VIA1 Dispatch", (void *) via1); #if 0 /* interferes with serial on some machines */ if (!psc_present) { request_irq(IRQ_AUTO_6, mac_bang, IRQ_FLG_LOCK, "Off Switch", mac_bang); } #endif } request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, "VIA2 Dispatch", (void *) via2); if (!psc_present) { request_irq(IRQ_AUTO_4, mac_SCC_handler, IRQ_FLG_LOCK, "SCC Dispatch", mac_SCC_handler); } request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, "Nubus Dispatch", (void *) via2); } /* * Debugging dump, used in various places to see what's going on. */ void via_debug_dump(void) { printk("VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", (uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]); printk(" PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n", (uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]); if (oss_present) { printk("VIA2: \n"); } else if (rbv_present) { printk("VIA2: IFR = 0x%02X IER = 0x%02X\n", (uint) via2[rIFR], (uint) via2[rIER]); printk(" SIFR = 0x%02X SIER = 0x%02X\n", (uint) via2[rSIFR], (uint) via2[rSIER]); } else { printk("VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n", (uint) via2[vDirA], (uint) via2[vDirB], (uint) via2[vACR]); printk(" 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; } /* * VIA-based power switch, for machines that support it. */ void via_poweroff(void) { if (rbv_present) { via2[rBufB] &= ~0x04; } else { /* Direction of vDirB is output */ via2[vDirB] |= 0x04; /* Send a value of 0 on that line */ via2[vBufB] &= ~0x04; /* Otherwise it prints "It is now.." then shuts off */ mdelay(1000); } /* We should never make it this far... */ printk ("It is now safe to switch off your machine.\n"); while(1); } /* * Initialize VIA2 for Nubus access */ void __init via_nubus_init(void) { nubus_active = 0; /* unlock nubus transactions */ if (!rbv_present) { /* set the line to be an output on non-RBV machines */ via2[vDirB] |= 0x02; } via2[gBufB] |= 0x02; /* disable nubus slot interrupts. */ if (rbv_present) { via2[rSIER] = 0x7F; /* like VIA; bit 7=clr,set */ } else { via2[vBufA] = 0xFF; /* active low irqs, force high */ via2[vDirA] = 0xFF; /* ddr to output. */ } } /* * The generic VIA interrupt routines (shamelessly stolen from Alan Cox's * via6522.c :-), disable/pending masks added. * * The new interrupt architecture in macints.c takes care of a lot of the * gruntwork for us, including tallying the interrupts and calling the * handlers on the linked list. All we need to do here is basically generate * the machspec interrupt number after clearing the interrupt. */ void via1_irq(int irq, void *dev_id, struct pt_regs *regs) { int irq_bit, i; unsigned char events, mask; irq -= VEC_SPUR; mask = via1[vIER] & 0x7F; if (!(events = via1[vIFR] & mask)) return; for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) if (events & irq_bit) { via1[vIER] = irq_bit; mac_do_irq_list(VIA1_SOURCE_BASE + i, regs); via1[vIFR] = irq_bit; via1[vIER] = irq_bit | 0x80; } if (!oss_present) { /* This (still) seems to be necessary to get IDE working. However, if you enable VBL interrupts, you're screwed... */ /* FIXME: should we check the SLOTIRQ bit before pulling this stunt? */ /* No, it won't be set. that's why we're doing this. */ via_irq_disable(IRQ_MAC_NUBUS); via_irq_clear(IRQ_MAC_NUBUS); mac_do_irq_list(IRQ_MAC_NUBUS, regs); via_irq_enable(IRQ_MAC_NUBUS); } } void via2_irq(int irq, void *dev_id, struct pt_regs *regs) { int irq_bit, i; unsigned char events, mask; irq -= VEC_SPUR; mask = via2[gIER] & 0x7F; if (!(events = via2[gIFR] & mask)) return; for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) if (events & irq_bit) { via2[gIER] = irq_bit; mac_do_irq_list(VIA2_SOURCE_BASE + i, regs); via2[gIFR] = irq_bit | rbv_clear; via2[gIER] = irq_bit | 0x80; } } /* * Dispatch Nubus interrupts. We are called as a secondary dispatch by the * VIA2 dispatcher as a fast interrupt handler. */ void via_nubus_irq(int irq, void *dev_id, struct pt_regs *regs) { int irq_bit, i; unsigned char events; if (!(events = ~via2[gBufA] & nubus_active)) return; for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) { if (events & irq_bit) { via_irq_disable(NUBUS_SOURCE_BASE + i); mac_do_irq_list(NUBUS_SOURCE_BASE + i, regs); via_irq_enable(NUBUS_SOURCE_BASE + i); } } } void via_irq_enable(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); int irq_bit = 1 << irq_idx; #ifdef DEBUG_IRQUSE printk("via_irq_enable(%d)\n", irq); #endif if (irq_src == 1) { via1[vIER] = irq_bit | 0x80; } else if (irq_src == 2) { /* * Set vPCR for SCSI interrupts (but not on RBV) */ if ((irq_idx == 0) && !rbv_present) { 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; } } via2[gIER] = irq_bit | 0x80; } else if (irq_src == 7) { if (rbv_present) { /* enable the slot interrupt. SIER works like IER. */ via2[rSIER] = IER_SET_BIT(irq_idx); } else { /* Make sure the bit is an input, to enable the irq */ via2[vDirA] &= ~irq_bit; } nubus_active |= irq_bit; } } void via_irq_disable(int irq) { int irq_src = IRQ_SRC(irq); int irq_idx = IRQ_IDX(irq); int irq_bit = 1 << irq_idx; #ifdef DEBUG_IRQUSE printk("via_irq_disable(%d)\n", irq); #endif if (irq_src == 1) { via1[vIER] = irq_bit; } else if (irq_src == 2) { via2[gIER] = irq_bit; } else if (irq_src == 7) { if (rbv_present) { /* disable the slot interrupt. SIER works like IER. */ via2[rSIER] = IER_CLR_BIT(irq_idx); } else { /* disable the nubus irq by changing dir to output */ via2[vDirA] |= irq_bit; } nubus_active &= ~irq_bit; } } 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: hmm.. */ } } /* * 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) { return ~via2[gBufA] & irq_bit; } return 0; } void via_scsi_clear(void) { volatile unsigned char deep_magic; #ifdef DEBUG_IRQUSE printk("via_scsi_clear()\n"); #endif /* We handle this in oss.c , but this gets called in mac_scsinew.c */ if(oss_present) return; if (rbv_present) { via2[rIFR] = (1<<3) | (1<<0) | rbv_clear; deep_magic = via2[rBufB]; } else { deep_magic = via2[vBufB]; } mac_enable_irq(IRQ_MAC_SCSI); } /* * PRAM/RTC access routines * * Must be called with interrupts disabled and * the RTC should be enabled. */ static __u8 via_pram_readbyte(void) { int i,reg; __u8 data; reg = via1[vBufB] & ~VIA1B_vRTCClk; /* Set the RTC data line to be an input. */ via1[vDirB] &= ~VIA1B_vRTCData; /* The bits of the byte come out in MSB order */ data = 0; for (i = 0 ; i < 8 ; i++) { via1[vBufB] = reg; via1[vBufB] = reg | VIA1B_vRTCClk; data = (data << 1) | (via1[vBufB] & VIA1B_vRTCData); } /* Return RTC data line to output state */ via1[vDirB] |= VIA1B_vRTCData; return data; } static void via_pram_writebyte(__u8 data) { int i,reg,bit; reg = via1[vBufB] & ~(VIA1B_vRTCClk | VIA1B_vRTCData); /* The bits of the byte go in in MSB order */ for (i = 0 ; i < 8 ; i++) { bit = data & 0x80? 1 : 0; data <<= 1; via1[vBufB] = reg | bit; via1[vBufB] = reg | bit | VIA1B_vRTCClk; } } /* * Execute a PRAM/RTC command. For read commands * data should point to a one-byte buffer for the * resulting data. For write commands it should point * to the data byte to for the command. * * This function disables all interrupts while running. */ void via_pram_command(int command, __u8 *data) { unsigned long cpu_flags; int is_read; save_flags(cpu_flags); cli(); /* Enable the RTC and make sure the strobe line is high */ via1[vBufB] = (via1[vBufB] | VIA1B_vRTCClk) & ~VIA1B_vRTCEnb; if (command & 0xFF00) { /* extended (two-byte) command */ via_pram_writebyte((command & 0xFF00) >> 8); via_pram_writebyte(command & 0xFF); is_read = command & 0x8000; } else { /* one-byte command */ via_pram_writebyte(command); is_read = command & 0x80; } if (is_read) { *data = via_pram_readbyte(); } else { via_pram_writebyte(*data); } /* All done, disable the RTC */ via1[vBufB] |= VIA1B_vRTCEnb; restore_flags(cpu_flags); } /* * Return the current time in seconds since January 1, 1904. * * This only works on machines with the VIA-based PRAM/RTC, which * is basically any machine with Mac II-style ADB. */ __u32 via_read_time(void) { union { __u8 cdata[4]; __u32 idata; } result, last_result; int ct; /* * The NetBSD guys say to loop until you get the same reading * twice in a row. */ ct = 0; do { if (++ct > 10) { printk("via_read_time: couldn't get valid time, " "last read = 0x%08X and 0x%08X\n", last_result.idata, result.idata); break; } last_result.idata = result.idata; result.idata = 0; via_pram_command(0x81, &result.cdata[3]); via_pram_command(0x85, &result.cdata[2]); via_pram_command(0x89, &result.cdata[1]); via_pram_command(0x8D, &result.cdata[0]); } while (result.idata != last_result.idata); return result.idata; } /* * Set the current time to a number of seconds since January 1, 1904. * * This only works on machines with the VIA-based PRAM/RTC, which * is basically any machine with Mac II-style ADB. */ void via_write_time(__u32 time) { union { __u8 cdata[4]; __u32 idata; } data; __u8 temp; /* Clear the write protect bit */ temp = 0x55; via_pram_command(0x35, &temp); data.idata = time; via_pram_command(0x01, &data.cdata[3]); via_pram_command(0x05, &data.cdata[2]); via_pram_command(0x09, &data.cdata[1]); via_pram_command(0x0D, &data.cdata[0]); /* Set the write protect bit */ temp = 0xD5; via_pram_command(0x35, &temp); }