m68k/mac: Optimize interrupts using chain handlers

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

4 files changed, 298 insertions, 63 deletions

diff --git a/arch/m68k/mac/baboon.c b/arch/m68k/mac/baboon.c
index ff11746b0621..425144cbfa7d 100644
--- a/arch/m68k/mac/baboon.c
+++ b/arch/m68k/mac/baboon.c
@@ -56,6 +56,39 @@ void __init baboon_init(void)
  * Baboon interrupt handler. This works a lot like a VIA.
  */
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+static void baboon_irq(unsigned int irq, struct irq_desc *desc)
+{
+        int irq_bit, irq_num;
+        unsigned char events;
+
+#ifdef DEBUG_IRQS
+        printk("baboon_irq: mb_control %02X mb_ifr %02X mb_status %02X\n",
+                (uint) baboon->mb_control, (uint) baboon->mb_ifr,
+                (uint) baboon->mb_status);
+#endif
+
+        events = baboon->mb_ifr & 0x07;
+        if (!events)
+                return;
+
+        irq_num = IRQ_BABOON_0;
+        irq_bit = 1;
+        do {
+                if (events & irq_bit) {
+                        baboon->mb_ifr &= ~irq_bit;
+                        generic_handle_irq(irq_num);
+                }
+                irq_bit <<= 1;
+                irq_num++;
+        } while(events >= irq_bit);
+#if 0
+        if (baboon->mb_ifr & 0x02) macide_ack_intr(NULL);
+        /* for now we need to smash all interrupts */
+        baboon->mb_ifr &= ~events;
+#endif
+}
+#else
 static irqreturn_t baboon_irq(int irq, void *dev_id)
 {
         int irq_bit, irq_num;
@@ -87,6 +120,7 @@ static irqreturn_t baboon_irq(int irq, void *dev_id)
 #endif
         return IRQ_HANDLED;
 }
+#endif
 
 /*
  * Register the Baboon interrupt dispatcher on nubus slot $C.
@@ -95,8 +129,12 @@ static irqreturn_t baboon_irq(int irq, void *dev_id)
 void __init baboon_register_interrupts(void)
 {
         baboon_disabled = 0;
+#ifdef CONFIG_GENERIC_HARDIRQS
+        irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
+#else
         if (request_irq(IRQ_NUBUS_C, baboon_irq, 0, "baboon", (void *)baboon))
                 pr_err("Couldn't register baboon interrupt\n");
+#endif
 }
 
 /*
diff --git a/arch/m68k/mac/oss.c b/arch/m68k/mac/oss.c
index ed952704e6ee..cc784c2ff6e8 100644
--- a/arch/m68k/mac/oss.c
+++ b/arch/m68k/mac/oss.c
@@ -32,10 +32,11 @@
 int oss_present;
 volatile struct mac_oss *oss;
 
-static irqreturn_t oss_irq(int, void *);
-static irqreturn_t oss_nubus_irq(int, void *);
-
+#ifdef CONFIG_GENERIC_HARDIRQS
+extern void via1_irq(unsigned int irq, struct irq_desc *desc);
+#else
 extern irqreturn_t via1_irq(int, void *);
+#endif
 
 /*
  * Initialize the OSS
@@ -63,23 +64,6 @@ void __init oss_init(void)
 }
 
 /*
- * Register the OSS and NuBus interrupt dispatchers.
- */
-
-void __init oss_register_interrupts(void)
-{
-        if (request_irq(OSS_IRQLEV_SCSI, oss_irq, 0, "scsi", (void *)oss))
-                pr_err("Couldn't register %s interrupt\n", "scsi");
-        if (request_irq(OSS_IRQLEV_NUBUS, oss_nubus_irq, 0, "nubus",
-                        (void *)oss))
-                pr_err("Couldn't register %s interrupt\n", "nubus");
-        if (request_irq(OSS_IRQLEV_SOUND, oss_irq, 0, "sound", (void *)oss))
-                pr_err("Couldn't register %s interrupt\n", "sound");
-        if (request_irq(OSS_IRQLEV_VIA1, via1_irq, 0, "via1", (void *)via1))
-                pr_err("Couldn't register %s interrupt\n", "via1");
-}
-
-/*
  * Initialize OSS for Nubus access
  */
 
@@ -92,6 +76,34 @@ void __init oss_nubus_init(void)
  * and SCSI; everything else is routed to its own autovector IRQ.
  */
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+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;
+
+#ifdef DEBUG_IRQS
+        if ((console_loglevel == 10) && !(events & OSS_IP_SCSI)) {
+                printk("oss_irq: irq %u events = 0x%04X\n", irq,
+                        (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) {
+                oss->irq_pending &= ~OSS_IP_SCSI;
+                generic_handle_irq(IRQ_MAC_SCSI);
+        } else {
+                /* FIXME: error check here? */
+        }
+}
+#else
 static irqreturn_t oss_irq(int irq, void *dev_id)
 {
         int events;
@@ -119,6 +131,7 @@ static irqreturn_t oss_irq(int irq, void *dev_id)
         }
         return IRQ_HANDLED;
 }
+#endif
 
 /*
  * Nubus IRQ handler, OSS style
@@ -126,6 +139,34 @@ static irqreturn_t oss_irq(int irq, void *dev_id)
  * Unlike the VIA/RBV this is on its own autovector interrupt level.
  */
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+static void oss_nubus_irq(unsigned int irq, struct irq_desc *desc)
+{
+        int events, irq_bit, i;
+
+        events = oss->irq_pending & OSS_IP_NUBUS;
+        if (!events)
+                return;
+
+#ifdef DEBUG_NUBUS_INT
+        if (console_loglevel > 7) {
+                printk("oss_nubus_irq: events = 0x%04X\n", events);
+        }
+#endif
+        /* There are only six slots on the OSS, not seven */
+
+        i = 6;
+        irq_bit = 0x40;
+        do {
+                --i;
+                irq_bit >>= 1;
+                if (events & irq_bit) {
+                        oss->irq_pending &= ~irq_bit;
+                        generic_handle_irq(NUBUS_SOURCE_BASE + i);
+                }
+        } while(events & (irq_bit - 1));
+}
+#else
 static irqreturn_t oss_nubus_irq(int irq, void *dev_id)
 {
         int events, irq_bit, i;
@@ -153,6 +194,31 @@ static irqreturn_t oss_nubus_irq(int irq, void *dev_id)
         } while(events & (irq_bit - 1));
         return IRQ_HANDLED;
 }
+#endif
+
+/*
+ * Register the OSS and NuBus interrupt dispatchers.
+ */
+
+void __init oss_register_interrupts(void)
+{
+#ifdef CONFIG_GENERIC_HARDIRQS
+        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);
+#else /* !CONFIG_GENERIC_HARDIRQS */
+        if (request_irq(OSS_IRQLEV_SCSI, oss_irq, 0, "scsi", (void *)oss))
+                pr_err("Couldn't register %s interrupt\n", "scsi");
+        if (request_irq(OSS_IRQLEV_NUBUS, oss_nubus_irq, 0, "nubus",
+                        (void *)oss))
+                pr_err("Couldn't register %s interrupt\n", "nubus");
+        if (request_irq(OSS_IRQLEV_SOUND, oss_irq, 0, "sound", (void *)oss))
+                pr_err("Couldn't register %s interrupt\n", "sound");
+        if (request_irq(OSS_IRQLEV_VIA1, via1_irq, 0, "via1", (void *)via1))
+                pr_err("Couldn't register %s interrupt\n", "via1");
+#endif /* !CONFIG_GENERIC_HARDIRQS */
+}
 
 /*
  * Enable an OSS interrupt
diff --git a/arch/m68k/mac/psc.c b/arch/m68k/mac/psc.c
index 0a34b7afc376..52840b8c03b8 100644
--- a/arch/m68k/mac/psc.c
+++ b/arch/m68k/mac/psc.c
@@ -33,8 +33,6 @@
 int psc_present;
 volatile __u8 *psc;
 
-irqreturn_t psc_irq(int, void *);
-
 /*
  * Debugging dump, used in various places to see what's going on.
  */
@@ -115,26 +113,40 @@ void __init psc_init(void)
 }
 
 /*
- * Register the PSC interrupt dispatchers for autovector interrupts 3-6.
+ * PSC interrupt handler. It's a lot like the VIA interrupt handler.
  */
 
-void __init psc_register_interrupts(void)
+#ifdef CONFIG_GENERIC_HARDIRQS
+static void psc_irq(unsigned int irq, struct irq_desc *desc)
 {
-        if (request_irq(IRQ_AUTO_3, psc_irq, 0, "psc3", (void *) 0x30))
-                pr_err("Couldn't register psc%d interrupt\n", 3);
-        if (request_irq(IRQ_AUTO_4, psc_irq, 0, "psc4", (void *) 0x40))
-                pr_err("Couldn't register psc%d interrupt\n", 4);
-        if (request_irq(IRQ_AUTO_5, psc_irq, 0, "psc5", (void *) 0x50))
-                pr_err("Couldn't register psc%d interrupt\n", 5);
-        if (request_irq(IRQ_AUTO_6, psc_irq, 0, "psc6", (void *) 0x60))
-                pr_err("Couldn't register psc%d interrupt\n", 6);
-}
+        unsigned int offset = (unsigned int)irq_desc_get_handler_data(desc);
+        int pIFR        = pIFRbase + offset;
+        int pIER        = pIERbase + offset;
+        int irq_num;
+        unsigned char irq_bit, events;
 
-/*
- * PSC interrupt handler. It's a lot like the VIA interrupt handler.
- */
+#ifdef DEBUG_IRQS
+        printk("psc_irq: irq %u pIFR = 0x%02X pIER = 0x%02X\n",
+                irq, (int) psc_read_byte(pIFR), (int) psc_read_byte(pIER));
+#endif
 
-irqreturn_t psc_irq(int irq, void *dev_id)
+        events = psc_read_byte(pIFR) & psc_read_byte(pIER) & 0xF;
+        if (!events)
+                return;
+
+        irq_num = irq << 3;
+        irq_bit = 1;
+        do {
+                if (events & irq_bit) {
+                        psc_write_byte(pIFR, irq_bit);
+                        generic_handle_irq(irq_num);
+                }
+                irq_num++;
+                irq_bit <<= 1;
+        } while (events >= irq_bit);
+}
+#else
+static irqreturn_t psc_irq(int irq, void *dev_id)
 {
         int pIFR        = pIFRbase + ((int) dev_id);
         int pIER        = pIERbase + ((int) dev_id);
@@ -162,6 +174,34 @@ irqreturn_t psc_irq(int irq, void *dev_id)
         } while (events >= irq_bit);
         return IRQ_HANDLED;
 }
+#endif
+
+/*
+ * Register the PSC interrupt dispatchers for autovector interrupts 3-6.
+ */
+
+void __init psc_register_interrupts(void)
+{
+#ifdef CONFIG_GENERIC_HARDIRQS
+        irq_set_chained_handler(IRQ_AUTO_3, psc_irq);
+        irq_set_handler_data(IRQ_AUTO_3, (void *)0x30);
+        irq_set_chained_handler(IRQ_AUTO_4, psc_irq);
+        irq_set_handler_data(IRQ_AUTO_4, (void *)0x40);
+        irq_set_chained_handler(IRQ_AUTO_5, psc_irq);
+        irq_set_handler_data(IRQ_AUTO_5, (void *)0x50);
+        irq_set_chained_handler(IRQ_AUTO_6, psc_irq);
+        irq_set_handler_data(IRQ_AUTO_6, (void *)0x60);
+#else /* !CONFIG_GENERIC_HARDIRQS */
+        if (request_irq(IRQ_AUTO_3, psc_irq, 0, "psc3", (void *) 0x30))
+                pr_err("Couldn't register psc%d interrupt\n", 3);
+        if (request_irq(IRQ_AUTO_4, psc_irq, 0, "psc4", (void *) 0x40))
+                pr_err("Couldn't register psc%d interrupt\n", 4);
+        if (request_irq(IRQ_AUTO_5, psc_irq, 0, "psc5", (void *) 0x50))
+                pr_err("Couldn't register psc%d interrupt\n", 5);
+        if (request_irq(IRQ_AUTO_6, psc_irq, 0, "psc6", (void *) 0x60))
+                pr_err("Couldn't register psc%d interrupt\n", 6);
+#endif /* !CONFIG_GENERIC_HARDIRQS */
+}
 
 void psc_irq_enable(int irq) {
         int irq_src     = IRQ_SRC(irq);
diff --git a/arch/m68k/mac/via.c b/arch/m68k/mac/via.c
index bde156caa46d..b8156ac496a0 100644
--- a/arch/m68k/mac/via.c
+++ b/arch/m68k/mac/via.c
@@ -80,9 +80,6 @@ static int gIER,gIFR,gBufA,gBufB;
 static u8 nubus_disabled;
 
 void via_debug_dump(void);
-irqreturn_t via1_irq(int, void *);
-irqreturn_t via2_irq(int, void *);
-irqreturn_t via_nubus_irq(int, void *);
 void via_irq_enable(int irq);
 void via_irq_disable(int irq);
 void via_irq_clear(int irq);
@@ -289,29 +286,6 @@ void __init via_init_clock(irq_handler_t func)
 }
 
 /*
- * Register the interrupt dispatchers for VIA or RBV machines only.
- */
-
-void __init via_register_interrupts(void)
-{
-        if (via_alt_mapping) {
-                if (request_irq(IRQ_AUTO_1, via1_irq, 0, "software",
-                                (void *)via1))
-                        pr_err("Couldn't register %s interrupt\n", "software");
-                if (request_irq(IRQ_AUTO_6, via1_irq, 0, "via1", (void *)via1))
-                        pr_err("Couldn't register %s interrupt\n", "via1");
-        } else {
-                if (request_irq(IRQ_AUTO_1, via1_irq, 0, "via1", (void *)via1))
-                        pr_err("Couldn't register %s interrupt\n", "via1");
-        }
-        if (request_irq(IRQ_AUTO_2, via2_irq, 0, "via2", (void *)via2))
-                pr_err("Couldn't register %s interrupt\n", "via2");
-        if (request_irq(IRQ_MAC_NUBUS, via_nubus_irq, 0, "nubus",
-                        (void *)via2))
-                pr_err("Couldn't register %s interrupt\n", "nubus");
-}
-
-/*
  * Debugging dump, used in various places to see what's going on.
  */
 
@@ -443,6 +417,49 @@ void __init via_nubus_init(void)
  * via6522.c :-), disable/pending masks added.
  */
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+void via1_irq(unsigned int irq, struct irq_desc *desc)
+{
+        int irq_num;
+        unsigned char irq_bit, events;
+
+        events = via1[vIFR] & via1[vIER] & 0x7F;
+        if (!events)
+                return;
+
+        irq_num = VIA1_SOURCE_BASE;
+        irq_bit = 1;
+        do {
+                if (events & irq_bit) {
+                        via1[vIFR] = irq_bit;
+                        generic_handle_irq(irq_num);
+                }
+                ++irq_num;
+                irq_bit <<= 1;
+        } while (events >= irq_bit);
+}
+
+static void via2_irq(unsigned int irq, struct irq_desc *desc)
+{
+        int irq_num;
+        unsigned char irq_bit, events;
+
+        events = via2[gIFR] & via2[gIER] & 0x7F;
+        if (!events)
+                return;
+
+        irq_num = VIA2_SOURCE_BASE;
+        irq_bit = 1;
+        do {
+                if (events & irq_bit) {
+                        via2[gIFR] = irq_bit | rbv_clear;
+                        generic_handle_irq(irq_num);
+                }
+                ++irq_num;
+                irq_bit <<= 1;
+        } while (events >= irq_bit);
+}
+#else
 irqreturn_t via1_irq(int irq, void *dev_id)
 {
         int irq_num;
@@ -486,12 +503,49 @@ irqreturn_t via2_irq(int irq, void *dev_id)
         } while (events >= irq_bit);
         return IRQ_HANDLED;
 }
+#endif
 
 /*
  * Dispatch Nubus interrupts. We are called as a secondary dispatch by the
  * VIA2 dispatcher as a fast interrupt handler.
  */
 
+#ifdef CONFIG_GENERIC_HARDIRQS
+void via_nubus_irq(unsigned int irq, struct irq_desc *desc)
+{
+        int slot_irq;
+        unsigned char slot_bit, events;
+
+        events = ~via2[gBufA] & 0x7F;
+        if (rbv_present)
+                events &= via2[rSIER];
+        else
+                events &= ~via2[vDirA];
+        if (!events)
+                return;
+
+        do {
+                slot_irq = IRQ_NUBUS_F;
+                slot_bit = 0x40;
+                do {
+                        if (events & slot_bit) {
+                                events &= ~slot_bit;
+                                generic_handle_irq(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 &= ~via2[vDirA];
+        } while (events);
+}
+#else
 irqreturn_t via_nubus_irq(int irq, void *dev_id)
 {
         int slot_irq;
@@ -527,6 +581,43 @@ irqreturn_t via_nubus_irq(int irq, void *dev_id)
         } while (events);
         return IRQ_HANDLED;
 }
+#endif
+
+/*
+ * Register the interrupt dispatchers for VIA or RBV machines only.
+ */
+
+void __init via_register_interrupts(void)
+{
+#ifdef CONFIG_GENERIC_HARDIRQS
+        if (via_alt_mapping) {
+                /* software interrupt */
+                irq_set_chained_handler(IRQ_AUTO_1, via1_irq);
+                /* via1 interrupt */
+                irq_set_chained_handler(IRQ_AUTO_6, via1_irq);
+        } else {
+                irq_set_chained_handler(IRQ_AUTO_1, via1_irq);
+        }
+        irq_set_chained_handler(IRQ_AUTO_2, via2_irq);
+        irq_set_chained_handler(IRQ_MAC_NUBUS, via_nubus_irq);
+#else
+        if (via_alt_mapping) {
+                if (request_irq(IRQ_AUTO_1, via1_irq, 0, "software",
+                                (void *)via1))
+                        pr_err("Couldn't register %s interrupt\n", "software");
+                if (request_irq(IRQ_AUTO_6, via1_irq, 0, "via1", (void *)via1))
+                        pr_err("Couldn't register %s interrupt\n", "via1");
+        } else {
+                if (request_irq(IRQ_AUTO_1, via1_irq, 0, "via1", (void *)via1))
+                        pr_err("Couldn't register %s interrupt\n", "via1");
+        }
+        if (request_irq(IRQ_AUTO_2, via2_irq, 0, "via2", (void *)via2))
+                pr_err("Couldn't register %s interrupt\n", "via2");
+        if (request_irq(IRQ_MAC_NUBUS, via_nubus_irq, 0, "nubus",
+                        (void *)via2))
+                pr_err("Couldn't register %s interrupt\n", "nubus");
+#endif
+}
 
 void via_irq_enable(int irq) {
         int irq_src     = IRQ_SRC(irq);