sh: intc - shared IPR and INTC2 controller

This is the second version of the shared interrupt controller patch
for the sh architecture, fixing up handling of intc_reg_fns[].

The three main advantages with this controller over the existing
ones are:

	- Both priority (ipr) and bitmap (intc2) registers are
	  supported
	- External pin sense configuration is supported, ie edge
	  vs level triggered
	- CPU/Board specific code maps 1:1 with datasheet for
	  easy verification

This controller can easily coexist with the current IPR and INTC2
controllers, but the idea is that CPUs/Boards should be moved over
to this controller over time so we have a single code base to
maintain.

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

2 files changed, 353 insertions, 0 deletions

diff --git a/arch/sh/kernel/cpu/irq/Makefile b/arch/sh/kernel/cpu/irq/Makefile
index 1c23308cfc2..9ddb446ac93 100644
--- a/arch/sh/kernel/cpu/irq/Makefile
+++ b/arch/sh/kernel/cpu/irq/Makefile
@@ -6,4 +6,5 @@ obj-y	+= imask.o
 obj-$(CONFIG_CPU_HAS_IPR_IRQ)		+= ipr.o
 obj-$(CONFIG_CPU_HAS_PINT_IRQ)		+= pint.o 
 obj-$(CONFIG_CPU_HAS_MASKREG_IRQ)	+= maskreg.o
+obj-$(CONFIG_CPU_HAS_INTC_IRQ)		+= intc.o
 obj-$(CONFIG_CPU_HAS_INTC2_IRQ)		+= intc2.o
diff --git a/arch/sh/kernel/cpu/irq/intc.c b/arch/sh/kernel/cpu/irq/intc.c
new file mode 100644
index 00000000000..626b4d8d793
--- /dev/null
+++ b/arch/sh/kernel/cpu/irq/intc.c
@@ -0,0 +1,352 @@
+/*
+ * Shared interrupt handling code for IPR and INTC2 types of IRQs.
+ *
+ * Copyright (C) 2007 Magnus Damm
+ *
+ * Based on intc2.c and ipr.c
+ *
+ * Copyright (C) 1999  Niibe Yutaka & Takeshi Yaegashi
+ * Copyright (C) 2000  Kazumoto Kojima
+ * Copyright (C) 2001  David J. Mckay (david.mckay@st.com)
+ * Copyright (C) 2003  Takashi Kusuda <kusuda-takashi@hitachi-ul.co.jp>
+ * Copyright (C) 2005, 2006  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+
+#define _INTC_MK(fn, idx, bit, value) \
+	((fn) << 24 | ((value) << 16) | ((idx) << 8) | (bit))
+#define _INTC_FN(h) (h >> 24)
+#define _INTC_VALUE(h) ((h >> 16) & 0xff)
+#define _INTC_IDX(h) ((h >> 8) & 0xff)
+#define _INTC_BIT(h) (h & 0xff)
+
+#define _INTC_PTR(desc, member, data) \
+	(desc->member + _INTC_IDX(data))
+
+static inline struct intc_desc *get_intc_desc(unsigned int irq)
+{
+	struct irq_chip *chip = get_irq_chip(irq);
+	return (void *)((char *)chip - offsetof(struct intc_desc, chip));
+}
+
+static inline unsigned int set_field(unsigned int value,
+				     unsigned int field_value,
+				     unsigned int width,
+				     unsigned int shift)
+{
+	value &= ~(((1 << width) - 1) << shift);
+	value |= field_value << shift;
+	return value;
+}
+
+static inline unsigned int set_prio_field(struct intc_desc *desc,
+					  unsigned int value,
+					  unsigned int priority,
+					  unsigned int data)
+{
+	unsigned int width = _INTC_PTR(desc, prio_regs, data)->field_width;
+
+	return set_field(value, priority, width, _INTC_BIT(data));
+}
+
+static void disable_prio_16(struct intc_desc *desc, unsigned int data)
+{
+	unsigned long addr = _INTC_PTR(desc, prio_regs, data)->reg;
+
+	ctrl_outw(set_prio_field(desc, ctrl_inw(addr), 0, data), addr);
+}
+
+static void enable_prio_16(struct intc_desc *desc, unsigned int data)
+{
+	unsigned long addr = _INTC_PTR(desc, prio_regs, data)->reg;
+	unsigned int prio = _INTC_VALUE(data);
+
+	ctrl_outw(set_prio_field(desc, ctrl_inw(addr), prio, data), addr);
+}
+
+static void disable_prio_32(struct intc_desc *desc, unsigned int data)
+{
+	unsigned long addr = _INTC_PTR(desc, prio_regs, data)->reg;
+
+	ctrl_outl(set_prio_field(desc, ctrl_inl(addr), 0, data), addr);
+}
+
+static void enable_prio_32(struct intc_desc *desc, unsigned int data)
+{
+	unsigned long addr = _INTC_PTR(desc, prio_regs, data)->reg;
+	unsigned int prio = _INTC_VALUE(data);
+
+	ctrl_outl(set_prio_field(desc, ctrl_inl(addr), prio, data), addr);
+}
+
+static void disable_mask_8(struct intc_desc *desc, unsigned int data)
+{
+	ctrl_outb(1 << _INTC_BIT(data),
+		  _INTC_PTR(desc, mask_regs, data)->set_reg);
+}
+
+static void enable_mask_8(struct intc_desc *desc, unsigned int data)
+{
+	ctrl_outb(1 << _INTC_BIT(data),
+		  _INTC_PTR(desc, mask_regs, data)->clr_reg);
+}
+
+static void disable_mask_32(struct intc_desc *desc, unsigned int data)
+{
+	ctrl_outl(1 << _INTC_BIT(data),
+		  _INTC_PTR(desc, mask_regs, data)->set_reg);
+}
+
+static void enable_mask_32(struct intc_desc *desc, unsigned int data)
+{
+	ctrl_outl(1 << _INTC_BIT(data),
+		  _INTC_PTR(desc, mask_regs, data)->clr_reg);
+}
+
+enum {	REG_FN_ERROR=0,
+	REG_FN_MASK_8, REG_FN_MASK_32,
+	REG_FN_PRIO_16, REG_FN_PRIO_32 };
+
+static struct {
+	void (*enable)(struct intc_desc *, unsigned int);
+	void (*disable)(struct intc_desc *, unsigned int);
+} intc_reg_fns[] = {
+	[REG_FN_MASK_8] = { enable_mask_8, disable_mask_8 },
+	[REG_FN_MASK_32] = { enable_mask_32, disable_mask_32 },
+	[REG_FN_PRIO_16] = { enable_prio_16, disable_prio_16 },
+	[REG_FN_PRIO_32] = { enable_prio_32, disable_prio_32 },
+};
+
+static void intc_enable(unsigned int irq)
+{
+	struct intc_desc *desc = get_intc_desc(irq);
+	unsigned int data = (unsigned int) get_irq_chip_data(irq);
+
+	intc_reg_fns[_INTC_FN(data)].enable(desc, data);
+}
+
+static void intc_disable(unsigned int irq)
+{
+	struct intc_desc *desc = get_intc_desc(irq);
+	unsigned int data = (unsigned int) get_irq_chip_data(irq);
+
+	intc_reg_fns[_INTC_FN(data)].disable(desc, data);
+}
+
+static void set_sense_16(struct intc_desc *desc, unsigned int data)
+{
+	unsigned long addr = _INTC_PTR(desc, sense_regs, data)->reg;
+	unsigned int width = _INTC_PTR(desc, sense_regs, data)->field_width;
+	unsigned int bit = _INTC_BIT(data);
+	unsigned int value = _INTC_VALUE(data);
+
+	ctrl_outw(set_field(ctrl_inw(addr), value, width, bit), addr);
+}
+
+static void set_sense_32(struct intc_desc *desc, unsigned int data)
+{
+	unsigned long addr = _INTC_PTR(desc, sense_regs, data)->reg;
+	unsigned int width = _INTC_PTR(desc, sense_regs, data)->field_width;
+	unsigned int bit = _INTC_BIT(data);
+	unsigned int value = _INTC_VALUE(data);
+
+	ctrl_outl(set_field(ctrl_inl(addr), value, width, bit), addr);
+}
+
+#define VALID(x) (x | 0x80)
+
+static unsigned char intc_irq_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
+	[IRQ_TYPE_EDGE_FALLING] = VALID(0),
+	[IRQ_TYPE_EDGE_RISING] = VALID(1),
+	[IRQ_TYPE_LEVEL_LOW] = VALID(2),
+	[IRQ_TYPE_LEVEL_HIGH] = VALID(3),
+};
+
+static int intc_set_sense(unsigned int irq, unsigned int type)
+{
+	struct intc_desc *desc = get_intc_desc(irq);
+	unsigned char value = intc_irq_sense_table[type & IRQ_TYPE_SENSE_MASK];
+	unsigned int i, j, data, bit;
+	intc_enum enum_id = 0;
+
+	for (i = 0; i < desc->nr_vectors; i++) {
+		struct intc_vect *vect = desc->vectors + i;
+
+		if (evt2irq(vect->vect) != irq)
+			continue;
+
+		enum_id = vect->enum_id;
+		break;
+	}
+
+	if (!enum_id || !value)
+		return -EINVAL;
+
+	value ^= VALID(0);
+
+	for (i = 0; i < desc->nr_sense_regs; i++) {
+		struct intc_sense_reg *sr = desc->sense_regs + i;
+
+		for (j = 0; j < ARRAY_SIZE(sr->enum_ids); j++) {
+			if (sr->enum_ids[j] != enum_id)
+				continue;
+
+			bit = sr->reg_width - ((j + 1) * sr->field_width);
+			data = _INTC_MK(0, i, bit, value);
+
+			switch(sr->reg_width) {
+			case 16:
+				set_sense_16(desc, data);
+				break;
+			case 32:
+				set_sense_32(desc, data);
+				break;
+			}
+
+			return 0;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static unsigned int __init intc_find_mask_handler(unsigned int width)
+{
+	switch (width) {
+	case 8:
+		return REG_FN_MASK_8;
+	case 32:
+		return REG_FN_MASK_32;
+	}
+
+	BUG();
+	return REG_FN_ERROR;
+}
+
+static unsigned int __init intc_find_prio_handler(unsigned int width)
+{
+	switch (width) {
+	case 16:
+		return REG_FN_PRIO_16;
+	case 32:
+		return REG_FN_PRIO_32;
+	}
+
+	BUG();
+	return REG_FN_ERROR;
+}
+
+static unsigned int __init intc_prio_value(struct intc_desc *desc,
+					   intc_enum enum_id)
+{
+	unsigned int i;
+
+	for (i = 0; i < desc->nr_priorities; i++) {
+		struct intc_prio *p = desc->priorities + i;
+
+		if (p->enum_id != enum_id)
+			continue;
+
+		return p->priority;
+	}
+
+	return 1; /* default to the lowest priority if no priority is set */
+}
+
+static unsigned int __init intc_mask_data(struct intc_desc *desc,
+					  intc_enum enum_id)
+{
+	unsigned int i, j, fn;
+
+	for (i = 0; i < desc->nr_mask_regs; i++) {
+		struct intc_mask_reg *mr = desc->mask_regs + i;
+
+		for (j = 0; j < ARRAY_SIZE(mr->enum_ids); j++) {
+			if (mr->enum_ids[j] != enum_id)
+				continue;
+
+			fn = intc_find_mask_handler(mr->reg_width);
+			if (fn == REG_FN_ERROR)
+				return 0;
+
+			return _INTC_MK(fn, i, (mr->reg_width - 1) - j, 0);
+		}
+	}
+
+	return 0;
+}
+
+static unsigned int __init intc_prio_data(struct intc_desc *desc,
+					  intc_enum enum_id)
+{
+	unsigned int i, j, fn, bit, prio;
+
+	for (i = 0; i < desc->nr_prio_regs; i++) {
+		struct intc_prio_reg *pr = desc->prio_regs + i;
+
+		for (j = 0; j < ARRAY_SIZE(pr->enum_ids); j++) {
+			if (pr->enum_ids[j] != enum_id)
+				continue;
+
+			fn = intc_find_prio_handler(pr->reg_width);
+			if (fn == REG_FN_ERROR)
+				return 0;
+
+			prio = intc_prio_value(desc, enum_id);
+			bit = pr->reg_width - ((j + 1) * pr->field_width);
+
+			BUG_ON(bit < 0);
+
+			return _INTC_MK(fn, i, bit, prio);
+		}
+	}
+
+	return 0;
+}
+
+static void __init intc_register_irq(struct intc_desc *desc, intc_enum enum_id,
+				     unsigned int irq)
+{
+	unsigned int mask_data = intc_mask_data(desc, enum_id);
+	unsigned int prio_data = intc_prio_data(desc, enum_id);
+	unsigned int data = mask_data ? mask_data : prio_data;
+
+	BUG_ON(!data);
+
+	disable_irq_nosync(irq);
+	set_irq_chip_and_handler_name(irq, &desc->chip,
+				      handle_level_irq, "level");
+	set_irq_chip_data(irq, (void *)data);
+
+	/* set priority */
+
+	if (prio_data)
+		intc_reg_fns[_INTC_FN(prio_data)].enable(desc, prio_data);
+
+	/* irq should be disabled by default */
+	desc->chip.mask(irq);
+}
+
+void __init register_intc_controller(struct intc_desc *desc)
+{
+	unsigned int i;
+
+	desc->chip.mask = intc_disable;
+	desc->chip.unmask = intc_enable;
+	desc->chip.mask_ack = intc_disable;
+	desc->chip.set_type = intc_set_sense;
+
+	for (i = 0; i < desc->nr_vectors; i++) {
+		struct intc_vect *vect = desc->vectors + i;
+
+		intc_register_irq(desc, vect->enum_id, evt2irq(vect->vect));
+	}
+}