Merge commit 'v3.3-rc6' into next

7 files changed, 295 insertions, 473 deletions

diff --git a/arch/m68k/mac/baboon.c b/arch/m68k/mac/baboon.c
index b403924a1ca..3fe0e43d44f 100644
--- a/arch/m68k/mac/baboon.c
+++ b/arch/m68k/mac/baboon.c
@@ -8,13 +8,8 @@
 
 #include <linux/types.h>
 #include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/delay.h>
-#include <linux/init.h>
 #include <linux/irq.h>
 
-#include <asm/traps.h>
-#include <asm/bootinfo.h>
 #include <asm/macintosh.h>
 #include <asm/macints.h>
 #include <asm/mac_baboon.h>
@@ -23,7 +18,6 @@
 
 int baboon_present;
 static volatile struct baboon *baboon;
-static unsigned char baboon_disabled;
 
 #if 0
 extern int macide_ack_intr(struct ata_channel *);
@@ -89,51 +83,32 @@ static void baboon_irq(unsigned int irq, struct irq_desc *desc)
 
 void __init baboon_register_interrupts(void)
 {
-	baboon_disabled = 0;
 	irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
 }
 
 /*
- * The means for masking individual baboon interrupts remains a mystery, so
- * enable the umbrella interrupt only when no baboon interrupt is disabled.
+ * The means for masking individual Baboon interrupts remains a mystery.
+ * However, since we only use the IDE IRQ, we can just enable/disable all
+ * Baboon interrupts. If/when we handle more than one Baboon IRQ, we must
+ * either figure out how to mask them individually or else implement the
+ * same workaround that's used for NuBus slots (see nubus_disabled and
+ * via_nubus_irq_shutdown).
  */
 
 void baboon_irq_enable(int irq)
 {
-	int irq_idx = IRQ_IDX(irq);
-
 #ifdef DEBUG_IRQUSE
 	printk("baboon_irq_enable(%d)\n", irq);
 #endif
 
-	baboon_disabled &= ~(1 << irq_idx);
-	if (!baboon_disabled)
-		mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C));
+	mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C));
 }
 
 void baboon_irq_disable(int irq)
 {
-	int irq_idx = IRQ_IDX(irq);
-
 #ifdef DEBUG_IRQUSE
 	printk("baboon_irq_disable(%d)\n", irq);
 #endif
 
-	baboon_disabled |= 1 << irq_idx;
-	if (baboon_disabled)
-		mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C));
-}
-
-void baboon_irq_clear(int irq)
-{
-	int irq_idx = IRQ_IDX(irq);
-
-	baboon->mb_ifr &= ~(1 << irq_idx);
-}
-
-int baboon_irq_pending(int irq)
-{
-	int irq_idx = IRQ_IDX(irq);
-
-	return baboon->mb_ifr & (1 << irq_idx);
+	mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C));
 }
diff --git a/arch/m68k/mac/config.c b/arch/m68k/mac/config.c
index c247de02bc7..f60ff5f5920 100644
--- a/arch/m68k/mac/config.c
+++ b/arch/m68k/mac/config.c
@@ -71,6 +71,31 @@ static void mac_get_model(char *str);
 static void mac_identify(void);
 static void mac_report_hardware(void);
 
+#ifdef CONFIG_EARLY_PRINTK
+asmlinkage void __init mac_early_print(const char *s, unsigned n);
+
+static void __init mac_early_cons_write(struct console *con,
+                                 const char *s, unsigned n)
+{
+	mac_early_print(s, n);
+}
+
+static struct console __initdata mac_early_cons = {
+	.name  = "early",
+	.write = mac_early_cons_write,
+	.flags = CON_PRINTBUFFER | CON_BOOT,
+	.index = -1
+};
+
+int __init mac_unregister_early_cons(void)
+{
+	/* mac_early_print can't be used after init sections are discarded */
+	return unregister_console(&mac_early_cons);
+}
+
+late_initcall(mac_unregister_early_cons);
+#endif
+
 static void __init mac_sched_init(irq_handler_t vector)
 {
 	via_init_clock(vector);
@@ -164,6 +189,10 @@ void __init config_mac(void)
 	mach_beep = mac_mksound;
 #endif
 
+#ifdef CONFIG_EARLY_PRINTK
+	register_console(&mac_early_cons);
+#endif
+
 	/*
 	 * Determine hardware present
 	 */
@@ -192,7 +221,7 @@ void __init config_mac(void)
  * inaccurate, so look here if a new Mac model won't run. Example: if
  * a Mac crashes immediately after the VIA1 registers have been dumped
  * to the screen, it probably died attempting to read DirB on a RBV.
- * Meaning it should have MAC_VIA_IIci here :-)
+ * Meaning it should have MAC_VIA_IICI here :-)
  */
 
 struct mac_model *macintosh_config;
@@ -267,7 +296,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_IICI,
 		.name		= "IIci",
 		.adb_type	= MAC_ADB_II,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -276,7 +305,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_IIFX,
 		.name		= "IIfx",
 		.adb_type	= MAC_ADB_IOP,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_IOP,
 		.nubus_type	= MAC_NUBUS,
@@ -285,7 +314,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_IISI,
 		.name		= "IIsi",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -294,7 +323,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_IIVI,
 		.name		= "IIvi",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -303,7 +332,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_IIVX,
 		.name		= "IIvx",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -318,7 +347,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_CLII,
 		.name		= "Classic II",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -327,7 +356,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_CCL,
 		.name		= "Color Classic",
 		.adb_type	= MAC_ADB_CUDA,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -336,7 +365,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_CCLII,
 		.name		= "Color Classic II",
 		.adb_type	= MAC_ADB_CUDA,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -351,7 +380,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_LC,
 		.name		= "LC",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -360,7 +389,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_LCII,
 		.name		= "LC II",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -369,7 +398,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_LCIII,
 		.name		= "LC III",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -497,7 +526,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_P460,
 		.name		= "Performa 460",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -524,7 +553,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_P520,
 		.name		= "Performa 520",
 		.adb_type	= MAC_ADB_CUDA,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -533,7 +562,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_P550,
 		.name		= "Performa 550",
 		.adb_type	= MAC_ADB_CUDA,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -565,7 +594,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_TV,
 		.name		= "TV",
 		.adb_type	= MAC_ADB_CUDA,
-		.via_type	= MAC_VIA_QUADRA,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -574,7 +603,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_P600,
 		.name		= "Performa 600",
 		.adb_type	= MAC_ADB_IISI,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_II,
 		.nubus_type	= MAC_NUBUS,
@@ -645,8 +674,8 @@ static struct mac_model mac_data_table[] = {
 	}, {
 		.ident		= MAC_MODEL_PB150,
 		.name		= "PowerBook 150",
-		.adb_type	= MAC_ADB_PB1,
-		.via_type	= MAC_VIA_IIci,
+		.adb_type	= MAC_ADB_PB2,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.ide_type	= MAC_IDE_PB,
 		.scc_type	= MAC_SCC_QUADRA,
@@ -732,17 +761,13 @@ static struct mac_model mac_data_table[] = {
 	 * PowerBook Duos are pretty much like normal PowerBooks
 	 * All of these probably have onboard SONIC in the Dock which
 	 * means we'll have to probe for it eventually.
-	 *
-	 * Are these really MAC_VIA_IIci? The developer notes for the
-	 * Duos show pretty much the same custom parts as in most of
-	 * the other PowerBooks which would imply MAC_VIA_QUADRA.
 	 */
 
 	{
 		.ident		= MAC_MODEL_PB210,
 		.name		= "PowerBook Duo 210",
 		.adb_type	= MAC_ADB_PB2,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_QUADRA,
 		.nubus_type	= MAC_NUBUS,
@@ -751,7 +776,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_PB230,
 		.name		= "PowerBook Duo 230",
 		.adb_type	= MAC_ADB_PB2,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_QUADRA,
 		.nubus_type	= MAC_NUBUS,
@@ -760,7 +785,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_PB250,
 		.name		= "PowerBook Duo 250",
 		.adb_type	= MAC_ADB_PB2,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_QUADRA,
 		.nubus_type	= MAC_NUBUS,
@@ -769,7 +794,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_PB270C,
 		.name		= "PowerBook Duo 270c",
 		.adb_type	= MAC_ADB_PB2,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_QUADRA,
 		.nubus_type	= MAC_NUBUS,
@@ -778,7 +803,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_PB280,
 		.name		= "PowerBook Duo 280",
 		.adb_type	= MAC_ADB_PB2,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_QUADRA,
 		.nubus_type	= MAC_NUBUS,
@@ -787,7 +812,7 @@ static struct mac_model mac_data_table[] = {
 		.ident		= MAC_MODEL_PB280C,
 		.name		= "PowerBook Duo 280c",
 		.adb_type	= MAC_ADB_PB2,
-		.via_type	= MAC_VIA_IIci,
+		.via_type	= MAC_VIA_IICI,
 		.scsi_type	= MAC_SCSI_OLD,
 		.scc_type	= MAC_SCC_QUADRA,
 		.nubus_type	= MAC_NUBUS,
@@ -864,8 +889,14 @@ static void __init mac_identify(void)
 		scc_b_rsrcs[1].start = scc_b_rsrcs[1].end = IRQ_MAC_SCC_B;
 		break;
 	default:
-		scc_a_rsrcs[1].start = scc_a_rsrcs[1].end = IRQ_MAC_SCC;
-		scc_b_rsrcs[1].start = scc_b_rsrcs[1].end = IRQ_MAC_SCC;
+		/* On non-PSC machines, the serial ports share an IRQ. */
+		if (macintosh_config->ident == MAC_MODEL_IIFX) {
+			scc_a_rsrcs[1].start = scc_a_rsrcs[1].end = IRQ_MAC_SCC;
+			scc_b_rsrcs[1].start = scc_b_rsrcs[1].end = IRQ_MAC_SCC;
+		} else {
+			scc_a_rsrcs[1].start = scc_a_rsrcs[1].end = IRQ_AUTO_4;
+			scc_b_rsrcs[1].start = scc_b_rsrcs[1].end = IRQ_AUTO_4;
+		}
 		break;
 	}
 
diff --git a/arch/m68k/mac/iop.c b/arch/m68k/mac/iop.c
index a5462cc0bfd..7d8d46127ad 100644
--- a/arch/m68k/mac/iop.c
+++ b/arch/m68k/mac/iop.c
@@ -115,7 +115,6 @@
 #include <asm/macintosh.h>
 #include <asm/macints.h>
 #include <asm/mac_iop.h>
-#include <asm/mac_oss.h>
 
 /*#define DEBUG_IOP*/
 
@@ -149,8 +148,6 @@ static struct listener iop_listeners[NUM_IOPS][NUM_IOP_CHAN];
 
 irqreturn_t iop_ism_irq(int, void *);
 
-extern void oss_irq_enable(int);
-
 /*
  * Private access functions
  */
@@ -304,11 +301,10 @@ void __init iop_init(void)
 void __init iop_register_interrupts(void)
 {
 	if (iop_ism_present) {
-		if (oss_present) {
-			if (request_irq(OSS_IRQLEV_IOPISM, iop_ism_irq, 0,
+		if (macintosh_config->ident == MAC_MODEL_IIFX) {
+			if (request_irq(IRQ_MAC_ADB, iop_ism_irq, 0,
 					"ISM IOP", (void *)IOP_NUM_ISM))
 				pr_err("Couldn't register ISM IOP interrupt\n");
-			oss_irq_enable(IRQ_MAC_ADB);
 		} else {
 			if (request_irq(IRQ_VIA2_0, iop_ism_irq, 0, "ISM IOP",
 					(void *)IOP_NUM_ISM))
diff --git a/arch/m68k/mac/macints.c b/arch/m68k/mac/macints.c
index ba220b70ab8..5c1a6b2ff0a 100644
--- a/arch/m68k/mac/macints.c
+++ b/arch/m68k/mac/macints.c
@@ -26,10 +26,6 @@
  *		  - slot 6: timer 1 (not on IIci)
  *		  - slot 7: status of IRQ; signals 'any enabled int.'
  *
- *	2	- OSS (IIfx only?)
- *		  - slot 0: SCSI interrupt
- *		  - slot 1: Sound interrupt
- *
  * Levels 3-6 vary by machine type. For VIA or RBV Macintoshes:
  *
  *	3	- unused (?)
@@ -42,21 +38,30 @@
  *
  *	6	- off switch (?)
  *
- * For OSS Macintoshes (IIfx only at this point):
+ * Machines with Quadra-like VIA hardware, except PSC and PMU machines, support
+ * an alternate interrupt mapping, as used by A/UX. It spreads ethernet and
+ * sound out to their own autovector IRQs and gives VIA1 a higher priority:
  *
- *	3	- Nubus interrupt
- *		  - slot 0: Slot $9
- *		  - slot 1: Slot $A
- *		  - slot 2: Slot $B
- *		  - slot 3: Slot $C
- *		  - slot 4: Slot $D
- *		  - slot 5: Slot $E
+ *	1	- unused (?)
  *
- *	4	- SCC IOP
+ *	3	- on-board SONIC
+ *
+ *	5	- Apple Sound Chip (ASC)
+ *
+ *	6	- VIA1
+ *
+ * For OSS Macintoshes (IIfx only), we apply an interrupt mapping similar to
+ * the Quadra (A/UX) mapping:
+ *
+ *	1	- ISM IOP (ADB)
  *
- *	5	- ISM IOP (ADB?)
+ *	2	- SCSI
  *
- *	6	- unused
+ *	3	- NuBus
+ *
+ *	4	- SCC IOP
+ *
+ *	6	- VIA1
  *
  * For PSC Macintoshes (660AV, 840AV):
  *
@@ -100,88 +105,29 @@
  *   case. They're hidden behind the Nubus slot $C interrupt thus adding a
  *   third layer of indirection. Why oh why did the Apple engineers do that?
  *
- * - We support "fast" and "slow" handlers, just like the Amiga port. The
- *   fast handlers are called first and with all interrupts disabled. They
- *   are expected to execute quickly (hence the name). The slow handlers are
- *   called last with interrupts enabled and the interrupt level restored.
- *   They must therefore be reentrant.
- *
- *   TODO:
- *
  */
 
-#include <linux/module.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
-#include <linux/kernel_stat.h>
-#include <linux/interrupt.h> /* for intr_count */
+#include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/delay.h>
-#include <linux/seq_file.h>
 
-#include <asm/system.h>
 #include <asm/irq.h>
-#include <asm/traps.h>
-#include <asm/bootinfo.h>
 #include <asm/macintosh.h>
+#include <asm/macints.h>
 #include <asm/mac_via.h>
 #include <asm/mac_psc.h>
+#include <asm/mac_oss.h>
+#include <asm/mac_iop.h>
+#include <asm/mac_baboon.h>
 #include <asm/hwtest.h>
-#include <asm/errno.h>
-#include <asm/macints.h>
 #include <asm/irq_regs.h>
-#include <asm/mac_oss.h>
 
 #define SHUTUP_SONIC
 
 /*
- * VIA/RBV hooks
- */
-
-extern void via_register_interrupts(void);
-extern void via_irq_enable(int);
-extern void via_irq_disable(int);
-extern void via_irq_clear(int);
-extern int  via_irq_pending(int);
-
-/*
- * OSS hooks
- */
-
-extern void oss_register_interrupts(void);
-extern void oss_irq_enable(int);
-extern void oss_irq_disable(int);
-extern void oss_irq_clear(int);
-extern int  oss_irq_pending(int);
-
-/*
- * PSC hooks
- */
-
-extern void psc_register_interrupts(void);
-extern void psc_irq_enable(int);
-extern void psc_irq_disable(int);
-extern void psc_irq_clear(int);
-extern int  psc_irq_pending(int);
-
-/*
- * IOP hooks
- */
-
-extern void iop_register_interrupts(void);
-
-/*
- * Baboon hooks
- */
-
-extern int baboon_present;
-
-extern void baboon_register_interrupts(void);
-extern void baboon_irq_enable(int);
-extern void baboon_irq_disable(int);
-extern void baboon_irq_clear(int);
-
-/*
  * console_loglevel determines NMI handler function
  */
 
@@ -190,10 +136,15 @@ irqreturn_t mac_debug_handler(int, void *);
 
 /* #define DEBUG_MACINTS */
 
+static unsigned int mac_irq_startup(struct irq_data *);
+static void mac_irq_shutdown(struct irq_data *);
+
 static struct irq_chip mac_irq_chip = {
 	.name		= "mac",
 	.irq_enable	= mac_irq_enable,
 	.irq_disable	= mac_irq_disable,
+	.irq_startup	= mac_irq_startup,
+	.irq_shutdown	= mac_irq_shutdown,
 };
 
 void __init mac_init_IRQ(void)
@@ -239,8 +190,6 @@ void __init mac_init_IRQ(void)
 /*
  *  mac_irq_enable - enable an interrupt source
  * mac_irq_disable - disable an interrupt source
- *   mac_clear_irq - clears a pending interrupt
- * mac_irq_pending - returns the pending status of an IRQ (nonzero = pending)
  *
  * These routines are just dispatchers to the VIA/OSS/PSC routines.
  */
@@ -252,8 +201,6 @@ void mac_irq_enable(struct irq_data *data)
 
 	switch(irq_src) {
 	case 1:
-		via_irq_enable(irq);
-		break;
 	case 2:
 	case 7:
 		if (oss_present)
@@ -262,6 +209,7 @@ void mac_irq_enable(struct irq_data *data)
 			via_irq_enable(irq);
 		break;
 	case 3:
+	case 4:
 	case 5:
 	case 6:
 		if (psc_present)
@@ -269,10 +217,6 @@ void mac_irq_enable(struct irq_data *data)
 		else if (oss_present)
 			oss_irq_enable(irq);
 		break;
-	case 4:
-		if (psc_present)
-			psc_irq_enable(irq);
-		break;
 	case 8:
 		if (baboon_present)
 			baboon_irq_enable(irq);
@@ -287,8 +231,6 @@ void mac_irq_disable(struct irq_data *data)
 
 	switch(irq_src) {
 	case 1:
-		via_irq_disable(irq);
-		break;
 	case 2:
 	case 7:
 		if (oss_present)
@@ -297,6 +239,7 @@ void mac_irq_disable(struct irq_data *data)
 			via_irq_disable(irq);
 		break;
 	case 3:
+	case 4:
 	case 5:
 	case 6:
 		if (psc_present)
@@ -304,10 +247,6 @@ void mac_irq_disable(struct irq_data *data)
 		else if (oss_present)
 			oss_irq_disable(irq);
 		break;
-	case 4:
-		if (psc_present)
-			psc_irq_disable(irq);
-		break;
 	case 8:
 		if (baboon_present)
 			baboon_irq_disable(irq);
@@ -315,65 +254,27 @@ void mac_irq_disable(struct irq_data *data)
 	}
 }
 
-void mac_clear_irq(unsigned int irq)
+static unsigned int mac_irq_startup(struct irq_data *data)
 {
-	switch(IRQ_SRC(irq)) {
-	case 1:
-		via_irq_clear(irq);
-		break;
-	case 2:
-	case 7:
-		if (oss_present)
-			oss_irq_clear(irq);
-		else
-			via_irq_clear(irq);
-		break;
-	case 3:
-	case 5:
-	case 6:
-		if (psc_present)
-			psc_irq_clear(irq);
-		else if (oss_present)
-			oss_irq_clear(irq);
-		break;
-	case 4:
-		if (psc_present)
-			psc_irq_clear(irq);
-		break;
-	case 8:
-		if (baboon_present)
-			baboon_irq_clear(irq);
-		break;
-	}
+	int irq = data->irq;
+
+	if (IRQ_SRC(irq) == 7 && !oss_present)
+		via_nubus_irq_startup(irq);
+	else
+		mac_irq_enable(data);
+
+	return 0;
 }
 
-int mac_irq_pending(unsigned int irq)
+static void mac_irq_shutdown(struct irq_data *data)
 {
-	switch(IRQ_SRC(irq)) {
-	case 1:
-		return via_irq_pending(irq);
-	case 2:
-	case 7:
-		if (oss_present)
-			return oss_irq_pending(irq);
-		else
-			return via_irq_pending(irq);
-	case 3:
-	case 5:
-	case 6:
-		if (psc_present)
-			return psc_irq_pending(irq);
-		else if (oss_present)
-			return oss_irq_pending(irq);
-		break;
-	case 4:
-		if (psc_present)
-			return psc_irq_pending(irq);
-		break;
-	}
-	return 0;
+	int irq = data->irq;
+
+	if (IRQ_SRC(irq) == 7 && !oss_present)
+		via_nubus_irq_shutdown(irq);
+	else
+		mac_irq_disable(data);
 }
-EXPORT_SYMBOL(mac_irq_pending);
 
 static int num_debug[8];
 
diff --git a/arch/m68k/mac/oss.c b/arch/m68k/mac/oss.c
index a4c82dab9ff..6c4c882c126 100644
--- a/arch/m68k/mac/oss.c
+++ b/arch/m68k/mac/oss.c
@@ -1,5 +1,5 @@
 /*
- *	OSS handling
+ *	Operating System Services (OSS) chip handling
  *	Written by Joshua M. Thompson (funaho@jurai.org)
  *
  *
@@ -30,8 +30,6 @@
 int oss_present;
 volatile struct mac_oss *oss;
 
-extern void via1_irq(unsigned int irq, struct irq_desc *desc);
-
 /*
  * Initialize the OSS
  *
@@ -51,10 +49,8 @@ void __init oss_init(void)
 	/* do this by setting the source's interrupt level to zero. */
 
 	for (i = 0; i <= OSS_NUM_SOURCES; i++) {
-		oss->irq_level[i] = OSS_IRQLEV_DISABLED;
+		oss->irq_level[i] = 0;
 	}
-	/* If we disable VIA1 here, we never really handle it... */
-	oss->irq_level[OSS_VIA1] = OSS_IRQLEV_VIA1;
 }
 
 /*
@@ -66,17 +62,13 @@ void __init oss_nubus_init(void)
 }
 
 /*
- * Handle miscellaneous OSS interrupts. Right now that's just sound
- * and SCSI; everything else is routed to its own autovector IRQ.
+ * Handle miscellaneous OSS interrupts.
  */
 
 static void oss_irq(unsigned int irq, struct irq_desc *desc)
 {
-	int events;
-
-	events = oss->irq_pending & (OSS_IP_SOUND|OSS_IP_SCSI);
-	if (!events)
-		return;
+	int events = oss->irq_pending &
+	             (OSS_IP_IOPSCC | OSS_IP_SCSI | OSS_IP_IOPISM);
 
 #ifdef DEBUG_IRQS
 	if ((console_loglevel == 10) && !(events & OSS_IP_SCSI)) {
@@ -84,16 +76,20 @@ static void oss_irq(unsigned int irq, struct irq_desc *desc)
 			(int) oss->irq_pending);
 	}
 #endif
-	/* FIXME: how do you clear a pending IRQ?    */
 
-	if (events & OSS_IP_SOUND) {
-		oss->irq_pending &= ~OSS_IP_SOUND;
-		/* FIXME: call sound handler */
-	} else if (events & OSS_IP_SCSI) {
+	if (events & OSS_IP_IOPSCC) {
+		oss->irq_pending &= ~OSS_IP_IOPSCC;
+		generic_handle_irq(IRQ_MAC_SCC);
+	}
+
+	if (events & OSS_IP_SCSI) {
 		oss->irq_pending &= ~OSS_IP_SCSI;
 		generic_handle_irq(IRQ_MAC_SCSI);
-	} else {
-		/* FIXME: error check here? */
+	}
+
+	if (events & OSS_IP_IOPISM) {
+		oss->irq_pending &= ~OSS_IP_IOPISM;
+		generic_handle_irq(IRQ_MAC_ADB);
 	}
 }
 
@@ -132,14 +128,29 @@ static void oss_nubus_irq(unsigned int irq, struct irq_desc *desc)
 
 /*
  * Register the OSS and NuBus interrupt dispatchers.
+ *
+ * This IRQ mapping is laid out with two things in mind: first, we try to keep
+ * things on their own levels to avoid having to do double-dispatches. Second,
+ * the levels match as closely as possible the alternate IRQ mapping mode (aka
+ * "A/UX mode") available on some VIA machines.
  */
 
+#define OSS_IRQLEV_IOPISM    IRQ_AUTO_1
+#define OSS_IRQLEV_SCSI      IRQ_AUTO_2
+#define OSS_IRQLEV_NUBUS     IRQ_AUTO_3
+#define OSS_IRQLEV_IOPSCC    IRQ_AUTO_4
+#define OSS_IRQLEV_VIA1      IRQ_AUTO_6
+
 void __init oss_register_interrupts(void)
 {
-	irq_set_chained_handler(OSS_IRQLEV_SCSI, oss_irq);
-	irq_set_chained_handler(OSS_IRQLEV_NUBUS, oss_nubus_irq);
-	irq_set_chained_handler(OSS_IRQLEV_SOUND, oss_irq);
-	irq_set_chained_handler(OSS_IRQLEV_VIA1, via1_irq);
+	irq_set_chained_handler(OSS_IRQLEV_IOPISM, oss_irq);
+	irq_set_chained_handler(OSS_IRQLEV_SCSI,   oss_irq);
+	irq_set_chained_handler(OSS_IRQLEV_NUBUS,  oss_nubus_irq);
+	irq_set_chained_handler(OSS_IRQLEV_IOPSCC, oss_irq);
+	irq_set_chained_handler(OSS_IRQLEV_VIA1,   via1_irq);
+
+	/* OSS_VIA1 gets enabled here because it has no machspec interrupt. */
+	oss->irq_level[OSS_VIA1] = IRQ_AUTO_6;
 }
 
 /*
@@ -158,13 +169,13 @@ void oss_irq_enable(int irq) {
 	switch(irq) {
 		case IRQ_MAC_SCC:
 			oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_IOPSCC;
-			break;
+			return;
 		case IRQ_MAC_ADB:
 			oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_IOPISM;
-			break;
+			return;
 		case IRQ_MAC_SCSI:
 			oss->irq_level[OSS_SCSI] = OSS_IRQLEV_SCSI;
-			break;
+			return;
 		case IRQ_NUBUS_9:
 		case IRQ_NUBUS_A:
 		case IRQ_NUBUS_B:
@@ -173,13 +184,11 @@ void oss_irq_enable(int irq) {
 		case IRQ_NUBUS_E:
 			irq -= NUBUS_SOURCE_BASE;
 			oss->irq_level[irq] = OSS_IRQLEV_NUBUS;
-			break;
-#ifdef DEBUG_IRQUSE
-		default:
-			printk("%s unknown irq %d\n", __func__, irq);
-			break;
-#endif
+			return;
 	}
+
+	if (IRQ_SRC(irq) == 1)
+		via_irq_enable(irq);
 }
 
 /*
@@ -195,50 +204,14 @@ void oss_irq_disable(int irq) {
 #endif
 	switch(irq) {
 		case IRQ_MAC_SCC:
-			oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_DISABLED;
-			break;
-		case IRQ_MAC_ADB:
-			oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_DISABLED;
-			break;
-		case IRQ_MAC_SCSI:
-			oss->irq_level[OSS_SCSI] = OSS_IRQLEV_DISABLED;
-			break;
-		case IRQ_NUBUS_9:
-		case IRQ_NUBUS_A:
-		case IRQ_NUBUS_B:
-		case IRQ_NUBUS_C:
-		case IRQ_NUBUS_D:
-		case IRQ_NUBUS_E:
-			irq -= NUBUS_SOURCE_BASE;
-			oss->irq_level[irq] = OSS_IRQLEV_DISABLED;
-			break;
-#ifdef DEBUG_IRQUSE
-		default:
-			printk("%s unknown irq %d\n", __func__, irq);
-			break;
-#endif
-	}
-}
-
-/*
- * Clear an OSS interrupt
- *
- * Not sure if this works or not but it's the only method I could
- * think of based on the contents of the mac_oss structure.
- */
-
-void oss_irq_clear(int irq) {
-	/* FIXME: how to do this on OSS? */
-	switch(irq) {
-		case IRQ_MAC_SCC:
-			oss->irq_pending &= ~OSS_IP_IOPSCC;
-			break;
+			oss->irq_level[OSS_IOPSCC] = 0;
+			return;
 		case IRQ_MAC_ADB:
-			oss->irq_pending &= ~OSS_IP_IOPISM;
-			break;
+			oss->irq_level[OSS_IOPISM] = 0;
+			return;
 		case IRQ_MAC_SCSI:
-			oss->irq_pending &= ~OSS_IP_SCSI;
-			break;
+			oss->irq_level[OSS_SCSI] = 0;
+			return;
 		case IRQ_NUBUS_9:
 		case IRQ_NUBUS_A:
 		case IRQ_NUBUS_B:
@@ -246,36 +219,10 @@ void oss_irq_clear(int irq) {
 		case IRQ_NUBUS_D:
 		case IRQ_NUBUS_E:
 			irq -= NUBUS_SOURCE_BASE;
-			oss->irq_pending &= ~(1 << irq);
-			break;
+			oss->irq_level[irq] = 0;
+			return;
 	}
-}
-
-/*
- * Check to see if a specific OSS interrupt is pending
- */
 
-int oss_irq_pending(int irq)
-{
-	switch(irq) {
-		case IRQ_MAC_SCC:
-			return oss->irq_pending & OSS_IP_IOPSCC;
-			break;
-		case IRQ_MAC_ADB:
-			return oss->irq_pending & OSS_IP_IOPISM;
-			break;
-		case IRQ_MAC_SCSI:
-			return oss->irq_pending & OSS_IP_SCSI;
-			break;
-		case IRQ_NUBUS_9:
-		case IRQ_NUBUS_A:
-		case IRQ_NUBUS_B:
-		case IRQ_NUBUS_C:
-		case IRQ_NUBUS_D:
-		case IRQ_NUBUS_E:
-			irq -= NUBUS_SOURCE_BASE;
-			return oss->irq_pending & (1 << irq);
-			break;
-	}
-	return 0;
+	if (IRQ_SRC(irq) == 1)
+		via_irq_disable(irq);
 }
diff --git a/arch/m68k/mac/psc.c b/arch/m68k/mac/psc.c
index e6c2d20f328..6f026fc302f 100644
--- a/arch/m68k/mac/psc.c
+++ b/arch/m68k/mac/psc.c
@@ -180,20 +180,3 @@ void psc_irq_disable(int irq) {
 #endif
 	psc_write_byte(pIER, 1 << irq_idx);
 }
-
-void psc_irq_clear(int irq) {
-	int irq_src	= IRQ_SRC(irq);
-	int irq_idx	= IRQ_IDX(irq);
-	int pIFR	= pIERbase + (irq_src << 4);
-
-	psc_write_byte(pIFR, 1 << irq_idx);
-}
-
-int psc_irq_pending(int irq)
-{
-	int irq_src	= IRQ_SRC(irq);
-	int irq_idx	= IRQ_IDX(irq);
-	int pIFR	= pIERbase + (irq_src << 4);
-
-	return psc_read_byte(pIFR) & (1 << irq_idx);
-}
diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c
index f1600ad2662..2d85662715f 100644
--- a/arch/m68k/mac/via.c
+++ b/arch/m68k/mac/via.c
@@ -63,24 +63,50 @@ static int gIER,gIFR,gBufA,gBufB;
 #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.
+
+/*
+ * On Macs with a genuine VIA chip there is no way to mask an individual slot
+ * interrupt. This limitation also seems to apply to VIA clone logic cores in
+ * Quadra-like ASICs. (RBV and OSS machines don't have this limitation.)
+ *
+ * We used to fake it by configuring the relevent VIA pin as an output
+ * (to mask the interrupt) or input (to unmask). That scheme did not work on
+ * (at least) the Quadra 700. A NuBus card's /NMRQ signal is an open-collector
+ * circuit (see Designing Cards and Drivers for Macintosh II and Macintosh SE,
+ * p. 10-11 etc) but VIA outputs are not (see datasheet).
+ *
+ * Driving these outputs high must cause the VIA to source current and the
+ * card to sink current when it asserts /NMRQ. Current will flow but the pin
+ * voltage is uncertain and so the /NMRQ condition may still cause a transition
+ * at the VIA2 CA1 input (which explains the lost interrupts). A side effect
+ * is that a disabled slot IRQ can never be tested as pending or not.
+ *
+ * Driving these outputs low doesn't work either. All the slot /NMRQ lines are
+ * (active low) OR'd together to generate the CA1 (aka "SLOTS") interrupt (see
+ * The Guide To Macintosh Family Hardware, 2nd edition p. 167). If we drive a
+ * disabled /NMRQ line low, the falling edge immediately triggers a CA1
+ * interrupt and all slot interrupts after that will generate no transition
+ * and therefore no interrupt, even after being re-enabled.
+ *
+ * So we make the VIA port A I/O lines inputs and use nubus_disabled to keep
+ * track of their states. When any slot IRQ becomes disabled we mask the CA1
+ * umbrella interrupt. Only when all slot IRQs become enabled do we unmask
+ * the CA1 interrupt. It must remain enabled even when cards have no interrupt
+ * handler registered. Drivers must therefore disable a slot interrupt at the
+ * device before they call free_irq (like shared and autovector interrupts).
+ *
+ * There is also a related problem when MacOS is used to boot Linux. A network
+ * card brought up by a MacOS driver may raise an interrupt while Linux boots.
+ * This can be fatal since it can't be handled until the right driver loads
+ * (if such a driver exists at all). Apparently related to this hardware
+ * limitation, "Designing Cards and Drivers", p. 9-8, says that a slot
+ * interrupt with no driver would crash MacOS (the book was written before
+ * the appearance of Macs with RBV or OSS).
  */
+
 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
@@ -100,7 +126,7 @@ void __init via_init(void)
 
 		/* IIci, IIsi, IIvx, IIvi (P6xx), LC series */
 
-		case MAC_VIA_IIci:
+		case MAC_VIA_IICI:
 			via1 = (void *) VIA1_BASE;
 			if (macintosh_config->ident == MAC_MODEL_IIFX) {
 				via2 = NULL;
@@ -197,38 +223,17 @@ void __init via_init(void)
 	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;
-		}
+	if ((macintosh_config->via_type == MAC_VIA_QUADRA) &&
+	    (macintosh_config->adb_type != MAC_ADB_PB1) &&
+	    (macintosh_config->adb_type != MAC_ADB_PB2) &&
+	    (macintosh_config->ident    != MAC_MODEL_C660) &&
+	    (macintosh_config->ident    != MAC_MODEL_Q840)) {
+		via_alt_mapping = 1;
+		via1[vDirB] |= 0x40;
+		via1[vBufB] &= ~0x40;
+	} else {
+		via_alt_mapping = 0;
+	}
 
 	/*
 	 * Now initialize VIA2. For RBV we just kill all interrupts;
@@ -248,22 +253,28 @@ void __init via_init(void)
 		via2[vACR] &= ~0x03; /* disable port A & B latches */
 	}
 
+	/* Everything below this point is VIA2 only... */
+
+	if (rbv_present)
+		return;
+
 	/*
-	 * Set vPCR for control line interrupts (but not on RBV)
+	 * Set vPCR for control line interrupts.
+	 *
+	 * CA1 (SLOTS IRQ), CB1 (ASC IRQ): negative edge trigger.
+	 *
+	 * Macs with ESP SCSI have a negative edge triggered SCSI interrupt.
+	 * Testing reveals that PowerBooks do too. However, the SE/30
+	 * schematic diagram shows an active high NCR5380 IRQ line.
 	 */
-	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;
-		}
+
+	pr_debug("VIA2 vPCR is 0x%02X\n", via2[vPCR]);
+	if (macintosh_config->via_type == MAC_VIA_II) {
+		/* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, pos. edge */
+		via2[vPCR] = 0x66;
+	} else {
+		/* CA2 (SCSI DRQ), CB2 (SCSI IRQ): indep. input, neg. edge */
+		via2[vPCR] = 0x22;
 	}
 }
 
@@ -378,34 +389,55 @@ void __init via_nubus_init(void)
 		via2[gBufB] |= 0x02;
 	}
 
-	/* Disable all the slot interrupts (where possible). */
+	/*
+	 * Disable the slot interrupts. On some hardware that's not possible.
+	 * On some hardware it's unclear what all of these I/O lines do.
+	 */
 
 	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;
-		}
+	case MAC_VIA_QUADRA:
+		pr_debug("VIA2 vDirA is 0x%02X\n", via2[vDirA]);
 		break;
-	case MAC_VIA_IIci:
+	case MAC_VIA_IICI:
 		/* RBV. Disable all the slot interrupts. SIER works like IER. */
 		via2[rSIER] = 0x7F;
 		break;
+	}
+}
+
+void via_nubus_irq_startup(int irq)
+{
+	int irq_idx = IRQ_IDX(irq);
+
+	switch (macintosh_config->via_type) {
+	case MAC_VIA_II:
 	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;
+		/* Make the port A line an input. Probably redundant. */
+		if (macintosh_config->via_type == MAC_VIA_II) {
+			/* The top two bits are RAM size outputs. */
+			via2[vDirA] &= 0xC0 | ~(1 << irq_idx);
+		} else {
+			/* Allow NuBus slots 9 through F. */
+			via2[vDirA] &= 0x80 | ~(1 << irq_idx);
 		}
+		/* fall through */
+	case MAC_VIA_IICI:
+		via_irq_enable(irq);
+		break;
+	}
+}
+
+void via_nubus_irq_shutdown(int irq)
+{
+	switch (macintosh_config->via_type) {
+	case MAC_VIA_II:
+	case MAC_VIA_QUADRA:
+		/* Ensure that the umbrella CA1 interrupt remains enabled. */
+		via_irq_enable(irq);
+		break;
+	case MAC_VIA_IICI:
+		via_irq_disable(irq);
 		break;
 	}
 }
@@ -531,25 +563,18 @@ void via_irq_enable(int irq) {
 	} else if (irq_src == 7) {
 		switch (macintosh_config->via_type) {
 		case MAC_VIA_II:
+		case MAC_VIA_QUADRA:
 			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:
+		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;
 		}
 	}
 }
@@ -569,60 +594,18 @@ void via_irq_disable(int irq) {
 	} else if (irq_src == 7) {
 		switch (macintosh_config->via_type) {
 		case MAC_VIA_II:
+		case MAC_VIA_QUADRA:
 			nubus_disabled |= 1 << irq_idx;
 			if (nubus_disabled)
 				via2[gIER] = IER_CLR_BIT(1);
 			break;
-		case MAC_VIA_IIci:
+		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)
@@ -631,3 +614,9 @@ void via1_set_head(int head)
 		via1[vBufA] |= VIA1A_vHeadSel;
 }
 EXPORT_SYMBOL(via1_set_head);
+
+int via2_scsi_drq_pending(void)
+{
+	return via2[gIFR] & (1 << IRQ_IDX(IRQ_MAC_SCSIDRQ));
+}
+EXPORT_SYMBOL(via2_scsi_drq_pending);