1 files changed, 87 insertions, 54 deletions

diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c
index 21b03180d9f4..0c1cc45c570d 100644
--- a/arch/m68k/mac/via.c
+++ b/arch/m68k/mac/via.c
@@ -13,6 +13,10 @@
  * for info.  A full-text web search on 6522 AND VIA will probably also
  * net some usefulness. <cananian@alumni.princeton.edu> 20apr1999
  *
+ * Additional data is here (the SY6522 was used in the Mac II etc):
+ *     http://www.6502.org/documents/datasheets/synertek/synertek_sy6522.pdf
+ *     http://www.6502.org/documents/datasheets/synertek/synertek_sy6522_programming_reference.pdf
+ *
  * PRAM/RTC access algorithms are from the NetBSD RTC toolkit version 1.08b
  * by Erik Vogan and adapted to Linux by Joshua M. Thompson (funaho@jurai.org)
  *
@@ -37,7 +41,7 @@ volatile __u8 *via1, *via2;
 /* 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;
+int rbv_present, via_alt_mapping;
 __u8 rbv_clear;
 
 /*
@@ -138,11 +142,11 @@ void __init via_init(void)
 
         printk(KERN_INFO "VIA2 at %p is ", via2);
         if (rbv_present) {
-                printk(KERN_INFO "an RBV\n");
+                printk("an RBV\n");
         } else if (oss_present) {
-                printk(KERN_INFO "an OSS\n");
+                printk("an OSS\n");
         } else {
-                printk(KERN_INFO "a 6522 or clone\n");
+                printk("a 6522 or clone\n");
         }
 
 #ifdef DEBUG_VIA
@@ -163,6 +167,7 @@ void __init via_init(void)
         via1[vT2CL] = 0;
         via1[vT2CH] = 0;
         via1[vACR] &= 0x3F;
+        via1[vACR] &= ~0x03; /* disable port A & B latches */
 
         /*
          * SE/30: disable video IRQ
@@ -234,6 +239,22 @@ void __init via_init(void)
                 via2[vT2CL] = 0;
                 via2[vT2CH] = 0;
                 via2[vACR] &= 0x3F;
+                via2[vACR] &= ~0x03; /* disable port A & B latches */
+        }
+
+        /*
+         * Set vPCR for SCSI interrupts (but not on RBV)
+         */
+        if (!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;
+                }
         }
 }
 
@@ -367,19 +388,14 @@ void __init via_nubus_init(void)
 
         /* unlock nubus transactions */
 
-        if (!rbv_present) {
+        if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
+            (macintosh_config->adb_type != MAC_ADB_PB2)) {
                 /* set the line to be an output on non-RBV machines */
-                if ((macintosh_config->adb_type != MAC_ADB_PB1) &&
-                   (macintosh_config->adb_type != MAC_ADB_PB2)) {
+                if (!rbv_present)
                         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)) {
+                /* this seems to be an ADB bit on PMU machines */
+                /* according to MkLinux.  -- jmt               */
                 via2[gBufB] |= 0x02;
         }
 
@@ -420,20 +436,25 @@ void __init via_nubus_init(void)
 
 irqreturn_t via1_irq(int irq, void *dev_id)
 {
-        int irq_bit, i;
-        unsigned char events, mask;
+        int irq_num;
+        unsigned char irq_bit, events;
 
-        mask = via1[vIER] & 0x7F;
-        if (!(events = via1[vIFR] & mask))
+        events = via1[vIFR] & via1[vIER] & 0x7F;
+        if (!events)
                 return IRQ_NONE;
 
-        for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
+        irq_num = VIA1_SOURCE_BASE;
+        irq_bit = 1;
+        do {
                 if (events & irq_bit) {
                         via1[vIER] = irq_bit;
                         via1[vIFR] = irq_bit;
-                        m68k_handle_int(VIA1_SOURCE_BASE + i);
+                        m68k_handle_int(irq_num);
                         via1[vIER] = irq_bit | 0x80;
                 }
+                ++irq_num;
+                irq_bit <<= 1;
+        } while (events >= irq_bit);
 
 #if 0 /* freakin' pmu is doing weird stuff */
         if (!oss_present) {
@@ -454,20 +475,25 @@ irqreturn_t via1_irq(int irq, void *dev_id)
 
 irqreturn_t via2_irq(int irq, void *dev_id)
 {
-        int irq_bit, i;
-        unsigned char events, mask;
+        int irq_num;
+        unsigned char irq_bit, events;
 
-        mask = via2[gIER] & 0x7F;
-        if (!(events = via2[gIFR] & mask))
+        events = via2[gIFR] & via2[gIER] & 0x7F;
+        if (!events)
                 return IRQ_NONE;
 
-        for (i = 0, irq_bit = 1 ; i < 7 ; i++, irq_bit <<= 1)
+        irq_num = VIA2_SOURCE_BASE;
+        irq_bit = 1;
+        do {
                 if (events & irq_bit) {
                         via2[gIER] = irq_bit;
                         via2[gIFR] = irq_bit | rbv_clear;
-                        m68k_handle_int(VIA2_SOURCE_BASE + i);
+                        m68k_handle_int(irq_num);
                         via2[gIER] = irq_bit | 0x80;
                 }
+                ++irq_num;
+                irq_bit <<= 1;
+        } while (events >= irq_bit);
         return IRQ_HANDLED;
 }
 
@@ -478,19 +504,37 @@ irqreturn_t via2_irq(int irq, void *dev_id)
 
 irqreturn_t via_nubus_irq(int irq, void *dev_id)
 {
-        int irq_bit, i;
-        unsigned char events;
-
-        if (!(events = ~via2[gBufA] & nubus_active))
+        int slot_irq;
+        unsigned char slot_bit, events;
+
+        events = ~via2[gBufA] & 0x7F;
+        if (rbv_present)
+                events &= via2[rSIER];
+        else
+                events &= nubus_active;
+        if (!events)
                 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);
-                        m68k_handle_int(NUBUS_SOURCE_BASE + i);
-                        via_irq_enable(NUBUS_SOURCE_BASE + i);
-                }
-        }
+        do {
+                slot_irq = IRQ_NUBUS_F;
+                slot_bit = 0x40;
+                do {
+                        if (events & slot_bit) {
+                                events &= ~slot_bit;
+                                m68k_handle_int(slot_irq);
+                        }
+                        --slot_irq;
+                        slot_bit >>= 1;
+                } while (events);
+
+                /* clear the CA1 interrupt and make certain there's no more. */
+                via2[gIFR] = 0x02 | rbv_clear;
+                events = ~via2[gBufA] & 0x7F;
+                if (rbv_present)
+                        events &= via2[rSIER];
+                else
+                        events &= nubus_active;
+        } while (events);
         return IRQ_HANDLED;
 }
 
@@ -506,20 +550,6 @@ void via_irq_enable(int irq) {
         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;
@@ -557,9 +587,9 @@ void via_irq_disable(int irq) {
 #endif
 
         if (irq_src == 1) {
-                via1[vIER] = irq_bit;
+                via1[vIER] = irq_bit & 0x7F;
         } else if (irq_src == 2) {
-                via2[gIER] = irq_bit;
+                via2[gIER] = irq_bit & 0x7F;
         } else if (irq_src == 7) {
                 if (rbv_present) {
                         /* disable the slot interrupt.  SIER works like IER. */
@@ -586,7 +616,9 @@ void via_irq_clear(int irq) {
         } else if (irq_src == 2) {
                 via2[gIFR] = irq_bit | rbv_clear;
         } else if (irq_src == 7) {
-                /* FIXME: hmm.. */
+                /* FIXME: There is no way to clear an individual nubus slot
+                 * IRQ flag, other than getting the device to do it.
+                 */
         }
 }
 
@@ -606,6 +638,7 @@ int via_irq_pending(int irq)
         } else if (irq_src == 2) {
                 return via2[gIFR] & irq_bit;
         } else if (irq_src == 7) {
+                /* FIXME: this can't work while a slot irq is disabled! */
                 return ~via2[gBufA] & irq_bit;
         }
         return 0;