sh: add interrupt ack code to sh3

This patch adds interrupt acknowledge code for external interrupt
sources on sh3 processors. Only really required for edge triggered
interrupts, but we ack regardless of sense configuration.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

3 files changed, 103 insertions, 7 deletions

diff --git a/arch/sh/kernel/cpu/irq/intc.c b/arch/sh/kernel/cpu/irq/intc.c
index 84806b2027f8..df3695406d80 100644
--- a/arch/sh/kernel/cpu/irq/intc.c
+++ b/arch/sh/kernel/cpu/irq/intc.c
@@ -1,7 +1,7 @@
 /*
  * Shared interrupt handling code for IPR and INTC2 types of IRQs.
  *
- * Copyright (C) 2007 Magnus Damm
+ * Copyright (C) 2007, 2008 Magnus Damm
  *
  * Based on intc2.c and ipr.c
  *
@@ -62,6 +62,9 @@ struct intc_desc_int {
 #endif
 
 static unsigned int intc_prio_level[NR_IRQS]; /* for now */
+#ifdef CONFIG_CPU_SH3
+static unsigned long ack_handle[NR_IRQS];
+#endif
 
 static inline struct intc_desc_int *get_intc_desc(unsigned int irq)
 {
@@ -219,6 +222,25 @@ static void intc_disable(unsigned int irq)
         }
 }
 
+#ifdef CONFIG_CPU_SH3
+static void intc_mask_ack(unsigned int irq)
+{
+        struct intc_desc_int *d = get_intc_desc(irq);
+        unsigned long handle = ack_handle[irq];
+        unsigned long addr;
+
+        intc_disable(irq);
+
+        /* read register and write zero only to the assocaited bit */
+
+        if (handle) {
+                addr = INTC_REG(d, _INTC_ADDR_D(handle), 0);
+                ctrl_inb(addr);
+                ctrl_outb(0x3f ^ set_field(0, 1, handle), addr);
+        }
+}
+#endif
+
 static struct intc_handle_int *intc_find_irq(struct intc_handle_int *hp,
                                              unsigned int nr_hp,
                                              unsigned int irq)
@@ -430,6 +452,40 @@ static unsigned int __init intc_prio_data(struct intc_desc *desc,
         return 0;
 }
 
+#ifdef CONFIG_CPU_SH3
+static unsigned int __init intc_ack_data(struct intc_desc *desc,
+                                          struct intc_desc_int *d,
+                                          intc_enum enum_id)
+{
+        struct intc_mask_reg *mr = desc->ack_regs;
+        unsigned int i, j, fn, mode;
+        unsigned long reg_e, reg_d;
+
+        for (i = 0; mr && enum_id && i < desc->nr_ack_regs; i++) {
+                mr = desc->ack_regs + i;
+
+                for (j = 0; j < ARRAY_SIZE(mr->enum_ids); j++) {
+                        if (mr->enum_ids[j] != enum_id)
+                                continue;
+
+                        fn = REG_FN_MODIFY_BASE;
+                        mode = MODE_ENABLE_REG;
+                        reg_e = mr->set_reg;
+                        reg_d = mr->set_reg;
+
+                        fn += (mr->reg_width >> 3) - 1;
+                        return _INTC_MK(fn, mode,
+                                        intc_get_reg(d, reg_e),
+                                        intc_get_reg(d, reg_d),
+                                        1,
+                                        (mr->reg_width - 1) - j);
+                }
+        }
+
+        return 0;
+}
+#endif
+
 static unsigned int __init intc_sense_data(struct intc_desc *desc,
                                            struct intc_desc_int *d,
                                            intc_enum enum_id)
@@ -530,6 +586,11 @@ static void __init intc_register_irq(struct intc_desc *desc,
 
         /* irq should be disabled by default */
         d->chip.mask(irq);
+
+#ifdef CONFIG_CPU_SH3
+        if (desc->ack_regs)
+                ack_handle[irq] = intc_ack_data(desc, d, enum_id);
+#endif
 }
 
 static unsigned int __init save_reg(struct intc_desc_int *d,
@@ -560,6 +621,9 @@ void __init register_intc_controller(struct intc_desc *desc)
         d->nr_reg += desc->prio_regs ? desc->nr_prio_regs * 2 : 0;
         d->nr_reg += desc->sense_regs ? desc->nr_sense_regs : 0;
 
+#ifdef CONFIG_CPU_SH3
+        d->nr_reg += desc->ack_regs ? desc->nr_ack_regs : 0;
+#endif
         d->reg = alloc_bootmem(d->nr_reg * sizeof(*d->reg));
 #ifdef CONFIG_SMP
         d->smp = alloc_bootmem(d->nr_reg * sizeof(*d->smp));
@@ -592,14 +656,23 @@ void __init register_intc_controller(struct intc_desc *desc)
                 }
         }
 
-        BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
-
         d->chip.name = desc->name;
         d->chip.mask = intc_disable;
         d->chip.unmask = intc_enable;
         d->chip.mask_ack = intc_disable;
         d->chip.set_type = intc_set_sense;
 
+#ifdef CONFIG_CPU_SH3
+        if (desc->ack_regs) {
+                for (i = 0; i < desc->nr_ack_regs; i++)
+                        k += save_reg(d, k, desc->ack_regs[i].set_reg, 0);
+
+                d->chip.mask_ack = intc_mask_ack;
+        }
+#endif
+
+        BUG_ON(k > 256); /* _INTC_ADDR_E() and _INTC_ADDR_D() are 8 bits */
+
         for (i = 0; i < desc->nr_vectors; i++) {
                 struct intc_vect *vect = desc->vectors + i;
 
diff --git a/arch/sh/kernel/cpu/sh3/setup-sh3.c b/arch/sh/kernel/cpu/sh3/setup-sh3.c
index 28e7d6553091..c98846857855 100644
--- a/arch/sh/kernel/cpu/sh3/setup-sh3.c
+++ b/arch/sh/kernel/cpu/sh3/setup-sh3.c
@@ -35,15 +35,22 @@ static struct intc_prio_reg prio_registers[] __initdata = {
         { 0xa4000018, 0, 16, 4, /* IPRD */ { 0, 0, IRQ5, IRQ4 } },
 };
 
+static struct intc_mask_reg ack_registers[] __initdata = {
+        { 0xa4000004, 0, 8, /* IRR0 */
+          { 0, 0, IRQ5, IRQ4, IRQ3, IRQ2, IRQ1, IRQ0 } },
+};
+
 static struct intc_sense_reg sense_registers[] __initdata = {
         { 0xa4000010, 16, 2, { 0, 0, IRQ5, IRQ4, IRQ3, IRQ2, IRQ1, IRQ0 } },
 };
 
-static DECLARE_INTC_DESC(intc_desc_irq0123, "sh3-irq0123", vectors_irq0123,
-                         NULL, NULL, prio_registers, sense_registers);
+static DECLARE_INTC_DESC_ACK(intc_desc_irq0123, "sh3-irq0123",
+                             vectors_irq0123, NULL, NULL,
+                             prio_registers, sense_registers, ack_registers);
 
-static DECLARE_INTC_DESC(intc_desc_irq45, "sh3-irq45", vectors_irq45,
-                         NULL, NULL, prio_registers, sense_registers);
+static DECLARE_INTC_DESC_ACK(intc_desc_irq45, "sh3-irq45",
+                             vectors_irq45, NULL, NULL,
+                             prio_registers, sense_registers, ack_registers);
 
 #define INTC_ICR1               0xa4000010UL
 #define INTC_ICR1_IRQLVL        (1<<14)
diff --git a/include/asm-sh/hw_irq.h b/include/asm-sh/hw_irq.h
index 9d7003c03562..7438d1e21bc9 100644
--- a/include/asm-sh/hw_irq.h
+++ b/include/asm-sh/hw_irq.h
@@ -79,6 +79,10 @@ struct intc_desc {
         struct intc_sense_reg *sense_regs;
         unsigned int nr_sense_regs;
         char *name;
+#ifdef CONFIG_CPU_SH3
+        struct intc_mask_reg *ack_regs;
+        unsigned int nr_ack_regs;
+#endif
 };
 
 #define _INTC_ARRAY(a) a, sizeof(a)/sizeof(*a)
@@ -91,6 +95,18 @@ struct intc_desc symbol __initdata = {					\
         chipname,                                                       \
 }
 
+#ifdef CONFIG_CPU_SH3
+#define DECLARE_INTC_DESC_ACK(symbol, chipname, vectors, groups,        \
+        mask_regs, prio_regs, sense_regs, ack_regs)                     \
+struct intc_desc symbol __initdata = {                                  \
+        _INTC_ARRAY(vectors), _INTC_ARRAY(groups),                      \
+        _INTC_ARRAY(mask_regs), _INTC_ARRAY(prio_regs),                 \
+        _INTC_ARRAY(sense_regs),                                        \
+        chipname,                                                       \
+        _INTC_ARRAY(ack_regs),                                          \
+}
+#endif
+
 void __init register_intc_controller(struct intc_desc *desc);
 int intc_set_priority(unsigned int irq, unsigned int prio);