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Diffstat (limited to 'arch/m68k/mac/via.c')
| -rw-r--r-- | arch/m68k/mac/via.c | 619 |
1 files changed, 619 insertions, 0 deletions
diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c new file mode 100644 index 00000000000..cd528bf7b43 --- /dev/null +++ b/arch/m68k/mac/via.c @@ -0,0 +1,619 @@ +/* + * 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. <cananian@alumni.princeton.edu> 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 <linux/types.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/ide.h> + +#include <asm/traps.h> +#include <asm/bootinfo.h> +#include <asm/macintosh.h> +#include <asm/macints.h> +#include <asm/machw.h> +#include <asm/mac_via.h> +#include <asm/mac_psc.h> + +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 + * _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) + +static int nubus_active; + +void via_debug_dump(void); +irqreturn_t via1_irq(int, void *, struct pt_regs *); +irqreturn_t via2_irq(int, void *, struct pt_regs *); +irqreturn_t 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 irqreturn_t mac_bang(int, void *, struct pt_regs *); +extern irqreturn_t mac_scc_dispatch(int, void *, struct pt_regs *); +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(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1); + + printk(KERN_INFO "VIA2 at %p is ", via2); + if (rbv_present) { + printk(KERN_INFO "an RBV\n"); + } else if (oss_present) { + printk(KERN_INFO "an OSS\n"); + } else { + printk(KERN_INFO "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(irqreturn_t (*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) { + cpu_request_irq(IRQ_AUTO_1, via1_irq, + IRQ_FLG_LOCK|IRQ_FLG_FAST, "software", + (void *) via1); + cpu_request_irq(IRQ_AUTO_6, via1_irq, + IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1", + (void *) via1); + } else { + cpu_request_irq(IRQ_AUTO_1, via1_irq, + IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1", + (void *) via1); +#if 0 /* interferes with serial on some machines */ + if (!psc_present) { + cpu_request_irq(IRQ_AUTO_6, mac_bang, IRQ_FLG_LOCK, + "Off Switch", mac_bang); + } +#endif + } + cpu_request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, + "via2", (void *) via2); + if (!psc_present) { + cpu_request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK, + "scc", mac_scc_dispatch); + } + request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST, + "nubus", (void *) via2); +} + +/* + * 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: <OSS>\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) +{ + /* don't set nubus_active = 0 here, it kills the Baboon */ + /* interrupt that we've already registered. */ + + /* unlock nubus transactions */ + + if (!rbv_present) { + /* set the line to be an output on non-RBV machines */ + if ((macintosh_config->adb_type != MAC_ADB_PB1) && + (macintosh_config->adb_type != MAC_ADB_PB2)) { + via2[vDirB] |= 0x02; + } + } + + /* this seems to be an ADB bit on PMU machines */ + /* according to MkLinux. -- jmt */ + + if ((macintosh_config->adb_type != MAC_ADB_PB1) && + (macintosh_config->adb_type != MAC_ADB_PB2)) { + via2[gBufB] |= 0x02; + } + + /* disable nubus slot interrupts. */ + if (rbv_present) { + via2[rSIER] = 0x7F; + via2[rSIER] = nubus_active | 0x80; + } else { + /* These are ADB bits on PMU */ + if ((macintosh_config->adb_type != MAC_ADB_PB1) && + (macintosh_config->adb_type != MAC_ADB_PB2)) { + switch(macintosh_config->ident) + { + case MAC_MODEL_II: + case MAC_MODEL_IIX: + case MAC_MODEL_IICX: + case MAC_MODEL_SE30: + via2[vBufA] |= 0x3F; + via2[vDirA] = ~nubus_active | 0xc0; + break; + default: + via2[vBufA] = 0xFF; + via2[vDirA] = ~nubus_active; + } + } + } +} + +/* + * 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. + */ + +irqreturn_t via1_irq(int irq, void *dev_id, struct pt_regs *regs) +{ + int irq_bit, i; + unsigned char events, mask; + + mask = via1[vIER] & 0x7F; + if (!(events = via1[vIFR] & mask)) + return IRQ_NONE; + + 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 0 /* freakin' pmu is doing weird stuff */ + 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); + } +#endif + return IRQ_HANDLED; +} + +irqreturn_t via2_irq(int irq, void *dev_id, struct pt_regs *regs) +{ + int irq_bit, i; + unsigned char events, mask; + + mask = via2[gIER] & 0x7F; + if (!(events = via2[gIFR] & mask)) + return IRQ_NONE; + + 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; + } + return IRQ_HANDLED; +} + +/* + * Dispatch Nubus interrupts. We are called as a secondary dispatch by the + * VIA2 dispatcher as a fast interrupt handler. + */ + +irqreturn_t 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 IRQ_NONE; + + 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); + } + } + return IRQ_HANDLED; +} + +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(KERN_DEBUG "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 */ + /* But not on PowerBooks, that's ADB... */ + if ((macintosh_config->adb_type != MAC_ADB_PB1) && + (macintosh_config->adb_type != MAC_ADB_PB2)) { + switch(macintosh_config->ident) + { + case MAC_MODEL_II: + case MAC_MODEL_IIX: + case MAC_MODEL_IICX: + case MAC_MODEL_SE30: + via2[vDirA] &= (~irq_bit | 0xc0); + break; + default: + 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(KERN_DEBUG "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 */ + /* except on PMU */ + if ((macintosh_config->adb_type != MAC_ADB_PB1) && + (macintosh_config->adb_type != MAC_ADB_PB2)) { + 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; +} |