607 lines
15 KiB
C
607 lines
15 KiB
C
/*
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* 6522 Versatile Interface Adapter (VIA)
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*
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* There are two of these on the Mac II. Some IRQ's are vectored
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* via them as are assorted bits and bobs - eg RTC, ADB.
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*
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* CSA: Motorola seems to have removed documentation on the 6522 from
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* their web site; try
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* http://nerini.drf.com/vectrex/other/text/chips/6522/
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* http://www.zymurgy.net/classic/vic20/vicdet1.htm
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* and
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* http://193.23.168.87/mikro_laborversuche/via_iobaustein/via6522_1.html
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* for info. A full-text web search on 6522 AND VIA will probably also
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* net some usefulness. <cananian@alumni.princeton.edu> 20apr1999
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*
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* PRAM/RTC access algorithms are from the NetBSD RTC toolkit version 1.08b
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* by Erik Vogan and adapted to Linux by Joshua M. Thompson (funaho@jurai.org)
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*
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/ide.h>
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#include <asm/bootinfo.h>
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#include <asm/macintosh.h>
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#include <asm/macints.h>
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#include <asm/machw.h>
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#include <asm/mac_via.h>
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#include <asm/mac_psc.h>
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volatile __u8 *via1, *via2;
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#if 0
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/* See note in mac_via.h about how this is possibly not useful */
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volatile long *via_memory_bogon=(long *)&via_memory_bogon;
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#endif
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int rbv_present,via_alt_mapping;
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__u8 rbv_clear;
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/*
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* Globals for accessing the VIA chip registers without having to
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* check if we're hitting a real VIA or an RBV. Normally you could
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* just hit the combined register (ie, vIER|rIER) but that seems to
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* break on AV Macs...probably because they actually decode more than
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* eight address bits. Why can't Apple engineers at least be
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* _consistently_ lazy? - 1999-05-21 (jmt)
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*/
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static int gIER,gIFR,gBufA,gBufB;
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/*
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* Timer defs.
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*/
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#define TICK_SIZE 10000
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#define MAC_CLOCK_TICK (783300/HZ) /* ticks per HZ */
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#define MAC_CLOCK_LOW (MAC_CLOCK_TICK&0xFF)
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#define MAC_CLOCK_HIGH (MAC_CLOCK_TICK>>8)
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static int nubus_active;
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void via_debug_dump(void);
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irqreturn_t via1_irq(int, void *, struct pt_regs *);
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irqreturn_t via2_irq(int, void *, struct pt_regs *);
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irqreturn_t via_nubus_irq(int, void *, struct pt_regs *);
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void via_irq_enable(int irq);
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void via_irq_disable(int irq);
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void via_irq_clear(int irq);
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extern irqreturn_t mac_scc_dispatch(int, void *, struct pt_regs *);
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extern int oss_present;
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/*
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* Initialize the VIAs
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*
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* First we figure out where they actually _are_ as well as what type of
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* VIA we have for VIA2 (it could be a real VIA or an RBV or even an OSS.)
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* Then we pretty much clear them out and disable all IRQ sources.
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*
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* Note: the OSS is actually "detected" here and not in oss_init(). It just
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* seems more logical to do it here since via_init() needs to know
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* these things anyways.
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*/
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void __init via_init(void)
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{
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switch(macintosh_config->via_type) {
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/* IIci, IIsi, IIvx, IIvi (P6xx), LC series */
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case MAC_VIA_IIci:
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via1 = (void *) VIA1_BASE;
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if (macintosh_config->ident == MAC_MODEL_IIFX) {
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via2 = NULL;
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rbv_present = 0;
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oss_present = 1;
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} else {
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via2 = (void *) RBV_BASE;
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rbv_present = 1;
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oss_present = 0;
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}
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if (macintosh_config->ident == MAC_MODEL_LCIII) {
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rbv_clear = 0x00;
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} else {
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/* on most RBVs (& unlike the VIAs), you */
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/* need to set bit 7 when you write to IFR */
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/* in order for your clear to occur. */
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rbv_clear = 0x80;
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}
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gIER = rIER;
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gIFR = rIFR;
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gBufA = rSIFR;
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gBufB = rBufB;
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break;
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/* Quadra and early MacIIs agree on the VIA locations */
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case MAC_VIA_QUADRA:
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case MAC_VIA_II:
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via1 = (void *) VIA1_BASE;
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via2 = (void *) VIA2_BASE;
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rbv_present = 0;
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oss_present = 0;
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rbv_clear = 0x00;
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gIER = vIER;
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gIFR = vIFR;
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gBufA = vBufA;
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gBufB = vBufB;
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break;
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default:
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panic("UNKNOWN VIA TYPE");
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}
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printk(KERN_INFO "VIA1 at %p is a 6522 or clone\n", via1);
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printk(KERN_INFO "VIA2 at %p is ", via2);
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if (rbv_present) {
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printk(KERN_INFO "an RBV\n");
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} else if (oss_present) {
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printk(KERN_INFO "an OSS\n");
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} else {
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printk(KERN_INFO "a 6522 or clone\n");
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}
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#ifdef DEBUG_VIA
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via_debug_dump();
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#endif
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/*
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* Shut down all IRQ sources, reset the timers, and
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* kill the timer latch on VIA1.
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*/
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via1[vIER] = 0x7F;
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via1[vIFR] = 0x7F;
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via1[vT1LL] = 0;
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via1[vT1LH] = 0;
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via1[vT1CL] = 0;
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via1[vT1CH] = 0;
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via1[vT2CL] = 0;
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via1[vT2CH] = 0;
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via1[vACR] &= 0x3F;
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/*
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* SE/30: disable video IRQ
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* XXX: testing for SE/30 VBL
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*/
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if (macintosh_config->ident == MAC_MODEL_SE30) {
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via1[vDirB] |= 0x40;
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via1[vBufB] |= 0x40;
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}
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/*
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* Set the RTC bits to a known state: all lines to outputs and
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* RTC disabled (yes that's 0 to enable and 1 to disable).
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*/
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via1[vDirB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk | VIA1B_vRTCData);
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via1[vBufB] |= (VIA1B_vRTCEnb | VIA1B_vRTCClk);
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/* Everything below this point is VIA2/RBV only... */
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if (oss_present) return;
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#if 1
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/* Some machines support an alternate IRQ mapping that spreads */
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/* Ethernet and Sound out to their own autolevel IRQs and moves */
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/* VIA1 to level 6. A/UX uses this mapping and we do too. Note */
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/* that the IIfx emulates this alternate mapping using the OSS. */
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switch(macintosh_config->ident) {
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case MAC_MODEL_C610:
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case MAC_MODEL_Q610:
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case MAC_MODEL_C650:
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case MAC_MODEL_Q650:
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case MAC_MODEL_Q700:
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case MAC_MODEL_Q800:
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case MAC_MODEL_Q900:
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case MAC_MODEL_Q950:
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via_alt_mapping = 1;
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via1[vDirB] |= 0x40;
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via1[vBufB] &= ~0x40;
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break;
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default:
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via_alt_mapping = 0;
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break;
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}
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#else
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via_alt_mapping = 0;
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#endif
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/*
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* Now initialize VIA2. For RBV we just kill all interrupts;
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* for a regular VIA we also reset the timers and stuff.
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*/
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via2[gIER] = 0x7F;
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via2[gIFR] = 0x7F | rbv_clear;
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if (!rbv_present) {
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via2[vT1LL] = 0;
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via2[vT1LH] = 0;
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via2[vT1CL] = 0;
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via2[vT1CH] = 0;
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via2[vT2CL] = 0;
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via2[vT2CH] = 0;
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via2[vACR] &= 0x3F;
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}
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}
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/*
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* Start the 100 Hz clock
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*/
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void __init via_init_clock(irqreturn_t (*func)(int, void *, struct pt_regs *))
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{
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via1[vACR] |= 0x40;
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via1[vT1LL] = MAC_CLOCK_LOW;
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via1[vT1LH] = MAC_CLOCK_HIGH;
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via1[vT1CL] = MAC_CLOCK_LOW;
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via1[vT1CH] = MAC_CLOCK_HIGH;
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request_irq(IRQ_MAC_TIMER_1, func, IRQ_FLG_LOCK, "timer", func);
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}
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/*
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* Register the interrupt dispatchers for VIA or RBV machines only.
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*/
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void __init via_register_interrupts(void)
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{
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if (via_alt_mapping) {
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request_irq(IRQ_AUTO_1, via1_irq,
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IRQ_FLG_LOCK|IRQ_FLG_FAST, "software",
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(void *) via1);
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request_irq(IRQ_AUTO_6, via1_irq,
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IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1",
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(void *) via1);
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} else {
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request_irq(IRQ_AUTO_1, via1_irq,
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IRQ_FLG_LOCK|IRQ_FLG_FAST, "via1",
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(void *) via1);
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}
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request_irq(IRQ_AUTO_2, via2_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
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"via2", (void *) via2);
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if (!psc_present) {
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request_irq(IRQ_AUTO_4, mac_scc_dispatch, IRQ_FLG_LOCK,
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"scc", mac_scc_dispatch);
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}
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request_irq(IRQ_MAC_NUBUS, via_nubus_irq, IRQ_FLG_LOCK|IRQ_FLG_FAST,
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"nubus", (void *) via2);
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}
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/*
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* Debugging dump, used in various places to see what's going on.
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*/
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void via_debug_dump(void)
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{
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printk(KERN_DEBUG "VIA1: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
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(uint) via1[vDirA], (uint) via1[vDirB], (uint) via1[vACR]);
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printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
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(uint) via1[vPCR], (uint) via1[vIFR], (uint) via1[vIER]);
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if (oss_present) {
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printk(KERN_DEBUG "VIA2: <OSS>\n");
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} else if (rbv_present) {
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printk(KERN_DEBUG "VIA2: IFR = 0x%02X IER = 0x%02X\n",
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(uint) via2[rIFR], (uint) via2[rIER]);
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printk(KERN_DEBUG " SIFR = 0x%02X SIER = 0x%02X\n",
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(uint) via2[rSIFR], (uint) via2[rSIER]);
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} else {
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printk(KERN_DEBUG "VIA2: DDRA = 0x%02X DDRB = 0x%02X ACR = 0x%02X\n",
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(uint) via2[vDirA], (uint) via2[vDirB],
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(uint) via2[vACR]);
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printk(KERN_DEBUG " PCR = 0x%02X IFR = 0x%02X IER = 0x%02X\n",
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(uint) via2[vPCR],
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(uint) via2[vIFR], (uint) via2[vIER]);
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}
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}
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/*
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* This is always executed with interrupts disabled.
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*
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* TBI: get time offset between scheduling timer ticks
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*/
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unsigned long mac_gettimeoffset (void)
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{
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unsigned long ticks, offset = 0;
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/* read VIA1 timer 2 current value */
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ticks = via1[vT1CL] | (via1[vT1CH] << 8);
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/* The probability of underflow is less than 2% */
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if (ticks > MAC_CLOCK_TICK - MAC_CLOCK_TICK / 50)
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/* Check for pending timer interrupt in VIA1 IFR */
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if (via1[vIFR] & 0x40) offset = TICK_SIZE;
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ticks = MAC_CLOCK_TICK - ticks;
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ticks = ticks * 10000L / MAC_CLOCK_TICK;
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return ticks + offset;
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}
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/*
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* Flush the L2 cache on Macs that have it by flipping
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* the system into 24-bit mode for an instant.
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*/
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void via_flush_cache(void)
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{
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via2[gBufB] &= ~VIA2B_vMode32;
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via2[gBufB] |= VIA2B_vMode32;
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}
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/*
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* Return the status of the L2 cache on a IIci
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*/
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int via_get_cache_disable(void)
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{
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/* Safeguard against being called accidentally */
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if (!via2) {
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printk(KERN_ERR "via_get_cache_disable called on a non-VIA machine!\n");
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return 1;
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}
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return (int) via2[gBufB] & VIA2B_vCDis;
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}
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/*
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* Initialize VIA2 for Nubus access
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*/
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void __init via_nubus_init(void)
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{
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/* don't set nubus_active = 0 here, it kills the Baboon */
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/* interrupt that we've already registered. */
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/* unlock nubus transactions */
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if (!rbv_present) {
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/* set the line to be an output on non-RBV machines */
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if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
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(macintosh_config->adb_type != MAC_ADB_PB2)) {
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via2[vDirB] |= 0x02;
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}
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}
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/* this seems to be an ADB bit on PMU machines */
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/* according to MkLinux. -- jmt */
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if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
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(macintosh_config->adb_type != MAC_ADB_PB2)) {
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via2[gBufB] |= 0x02;
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}
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/* disable nubus slot interrupts. */
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if (rbv_present) {
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via2[rSIER] = 0x7F;
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via2[rSIER] = nubus_active | 0x80;
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} else {
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/* These are ADB bits on PMU */
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if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
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(macintosh_config->adb_type != MAC_ADB_PB2)) {
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switch(macintosh_config->ident)
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{
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case MAC_MODEL_II:
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case MAC_MODEL_IIX:
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case MAC_MODEL_IICX:
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case MAC_MODEL_SE30:
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via2[vBufA] |= 0x3F;
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via2[vDirA] = ~nubus_active | 0xc0;
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break;
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default:
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via2[vBufA] = 0xFF;
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via2[vDirA] = ~nubus_active;
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}
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}
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}
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}
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/*
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* The generic VIA interrupt routines (shamelessly stolen from Alan Cox's
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* via6522.c :-), disable/pending masks added.
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*
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* The new interrupt architecture in macints.c takes care of a lot of the
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* gruntwork for us, including tallying the interrupts and calling the
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* handlers on the linked list. All we need to do here is basically generate
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* the machspec interrupt number after clearing the interrupt.
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*/
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irqreturn_t via1_irq(int irq, void *dev_id, struct pt_regs *regs)
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{
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int irq_bit, i;
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unsigned char events, mask;
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mask = via1[vIER] & 0x7F;
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if (!(events = via1[vIFR] & mask))
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return IRQ_NONE;
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for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
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if (events & irq_bit) {
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via1[vIER] = irq_bit;
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m68k_handle_int(VIA1_SOURCE_BASE + i, regs);
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via1[vIFR] = irq_bit;
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via1[vIER] = irq_bit | 0x80;
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}
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#if 0 /* freakin' pmu is doing weird stuff */
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if (!oss_present) {
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/* This (still) seems to be necessary to get IDE
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working. However, if you enable VBL interrupts,
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you're screwed... */
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/* FIXME: should we check the SLOTIRQ bit before
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pulling this stunt? */
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/* No, it won't be set. that's why we're doing this. */
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via_irq_disable(IRQ_MAC_NUBUS);
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via_irq_clear(IRQ_MAC_NUBUS);
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m68k_handle_int(IRQ_MAC_NUBUS, regs);
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via_irq_enable(IRQ_MAC_NUBUS);
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}
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#endif
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return IRQ_HANDLED;
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}
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irqreturn_t via2_irq(int irq, void *dev_id, struct pt_regs *regs)
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{
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int irq_bit, i;
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unsigned char events, mask;
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mask = via2[gIER] & 0x7F;
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if (!(events = via2[gIFR] & mask))
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return IRQ_NONE;
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for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
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if (events & irq_bit) {
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via2[gIER] = irq_bit;
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via2[gIFR] = irq_bit | rbv_clear;
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m68k_handle_int(VIA2_SOURCE_BASE + i, regs);
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via2[gIER] = irq_bit | 0x80;
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}
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return IRQ_HANDLED;
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}
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/*
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* Dispatch Nubus interrupts. We are called as a secondary dispatch by the
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* VIA2 dispatcher as a fast interrupt handler.
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*/
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irqreturn_t via_nubus_irq(int irq, void *dev_id, struct pt_regs *regs)
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{
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int irq_bit, i;
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unsigned char events;
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if (!(events = ~via2[gBufA] & nubus_active))
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return IRQ_NONE;
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for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1) {
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if (events & irq_bit) {
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via_irq_disable(NUBUS_SOURCE_BASE + i);
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m68k_handle_int(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) {
|
|
nubus_active |= irq_bit;
|
|
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;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
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;
|
|
}
|