1 files changed, 394 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-omap-intc.c b/drivers/irqchip/irq-omap-intc.c
new file mode 100644
index 000000000..d360a6edd
--- /dev/null
+++ b/drivers/irqchip/irq-omap-intc.c
@@ -0,0 +1,394 @@
+/*
+ * linux/arch/arm/mach-omap2/irq.c
+ *
+ * Interrupt handler for OMAP2 boards.
+ *
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Paul Mundt <paul.mundt@nokia.com>
+ *
+ * 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/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+
+#include <asm/exception.h>
+#include <linux/irqchip.h>
+#include <linux/irqdomain.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <linux/irqchip/irq-omap-intc.h>
+
+/* selected INTC register offsets */
+
+#define INTC_REVISION		0x0000
+#define INTC_SYSCONFIG		0x0010
+#define INTC_SYSSTATUS		0x0014
+#define INTC_SIR		0x0040
+#define INTC_CONTROL		0x0048
+#define INTC_PROTECTION		0x004C
+#define INTC_IDLE		0x0050
+#define INTC_THRESHOLD		0x0068
+#define INTC_MIR0		0x0084
+#define INTC_MIR_CLEAR0		0x0088
+#define INTC_MIR_SET0		0x008c
+#define INTC_PENDING_IRQ0	0x0098
+#define INTC_PENDING_IRQ1	0x00b8
+#define INTC_PENDING_IRQ2	0x00d8
+#define INTC_PENDING_IRQ3	0x00f8
+#define INTC_ILR0		0x0100
+
+#define ACTIVEIRQ_MASK		0x7f	/* omap2/3 active interrupt bits */
+#define SPURIOUSIRQ_MASK	(0x1ffffff << 7)
+#define INTCPS_NR_ILR_REGS	128
+#define INTCPS_NR_MIR_REGS	4
+
+#define INTC_IDLE_FUNCIDLE	(1 << 0)
+#define INTC_IDLE_TURBO		(1 << 1)
+
+#define INTC_PROTECTION_ENABLE	(1 << 0)
+
+struct omap_intc_regs {
+	u32 sysconfig;
+	u32 protection;
+	u32 idle;
+	u32 threshold;
+	u32 ilr[INTCPS_NR_ILR_REGS];
+	u32 mir[INTCPS_NR_MIR_REGS];
+};
+static struct omap_intc_regs intc_context;
+
+static struct irq_domain *domain;
+static void __iomem *omap_irq_base;
+static int omap_nr_pending;
+static int omap_nr_irqs;
+
+static void intc_writel(u32 reg, u32 val)
+{
+	writel_relaxed(val, omap_irq_base + reg);
+}
+
+static u32 intc_readl(u32 reg)
+{
+	return readl_relaxed(omap_irq_base + reg);
+}
+
+void omap_intc_save_context(void)
+{
+	int i;
+
+	intc_context.sysconfig =
+		intc_readl(INTC_SYSCONFIG);
+	intc_context.protection =
+		intc_readl(INTC_PROTECTION);
+	intc_context.idle =
+		intc_readl(INTC_IDLE);
+	intc_context.threshold =
+		intc_readl(INTC_THRESHOLD);
+
+	for (i = 0; i < omap_nr_irqs; i++)
+		intc_context.ilr[i] =
+			intc_readl((INTC_ILR0 + 0x4 * i));
+	for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
+		intc_context.mir[i] =
+			intc_readl(INTC_MIR0 + (0x20 * i));
+}
+
+void omap_intc_restore_context(void)
+{
+	int i;
+
+	intc_writel(INTC_SYSCONFIG, intc_context.sysconfig);
+	intc_writel(INTC_PROTECTION, intc_context.protection);
+	intc_writel(INTC_IDLE, intc_context.idle);
+	intc_writel(INTC_THRESHOLD, intc_context.threshold);
+
+	for (i = 0; i < omap_nr_irqs; i++)
+		intc_writel(INTC_ILR0 + 0x4 * i,
+				intc_context.ilr[i]);
+
+	for (i = 0; i < INTCPS_NR_MIR_REGS; i++)
+		intc_writel(INTC_MIR0 + 0x20 * i,
+			intc_context.mir[i]);
+	/* MIRs are saved and restore with other PRCM registers */
+}
+
+void omap3_intc_prepare_idle(void)
+{
+	/*
+	 * Disable autoidle as it can stall interrupt controller,
+	 * cf. errata ID i540 for 3430 (all revisions up to 3.1.x)
+	 */
+	intc_writel(INTC_SYSCONFIG, 0);
+	intc_writel(INTC_IDLE, INTC_IDLE_TURBO);
+}
+
+void omap3_intc_resume_idle(void)
+{
+	/* Re-enable autoidle */
+	intc_writel(INTC_SYSCONFIG, 1);
+	intc_writel(INTC_IDLE, 0);
+}
+
+/* XXX: FIQ and additional INTC support (only MPU at the moment) */
+static void omap_ack_irq(struct irq_data *d)
+{
+	intc_writel(INTC_CONTROL, 0x1);
+}
+
+static void omap_mask_ack_irq(struct irq_data *d)
+{
+	irq_gc_mask_disable_reg(d);
+	omap_ack_irq(d);
+}
+
+static void __init omap_irq_soft_reset(void)
+{
+	unsigned long tmp;
+
+	tmp = intc_readl(INTC_REVISION) & 0xff;
+
+	pr_info("IRQ: Found an INTC at 0x%p (revision %ld.%ld) with %d interrupts\n",
+		omap_irq_base, tmp >> 4, tmp & 0xf, omap_nr_irqs);
+
+	tmp = intc_readl(INTC_SYSCONFIG);
+	tmp |= 1 << 1;	/* soft reset */
+	intc_writel(INTC_SYSCONFIG, tmp);
+
+	while (!(intc_readl(INTC_SYSSTATUS) & 0x1))
+		/* Wait for reset to complete */;
+
+	/* Enable autoidle */
+	intc_writel(INTC_SYSCONFIG, 1 << 0);
+}
+
+int omap_irq_pending(void)
+{
+	int i;
+
+	for (i = 0; i < omap_nr_pending; i++)
+		if (intc_readl(INTC_PENDING_IRQ0 + (0x20 * i)))
+			return 1;
+	return 0;
+}
+
+void omap3_intc_suspend(void)
+{
+	/* A pending interrupt would prevent OMAP from entering suspend */
+	omap_ack_irq(NULL);
+}
+
+static int __init omap_alloc_gc_of(struct irq_domain *d, void __iomem *base)
+{
+	int ret;
+	int i;
+
+	ret = irq_alloc_domain_generic_chips(d, 32, 1, "INTC",
+			handle_level_irq, IRQ_NOREQUEST | IRQ_NOPROBE,
+			IRQ_LEVEL, 0);
+	if (ret) {
+		pr_warn("Failed to allocate irq chips\n");
+		return ret;
+	}
+
+	for (i = 0; i < omap_nr_pending; i++) {
+		struct irq_chip_generic *gc;
+		struct irq_chip_type *ct;
+
+		gc = irq_get_domain_generic_chip(d, 32 * i);
+		gc->reg_base = base;
+		ct = gc->chip_types;
+
+		ct->type = IRQ_TYPE_LEVEL_MASK;
+
+		ct->chip.irq_ack = omap_mask_ack_irq;
+		ct->chip.irq_mask = irq_gc_mask_disable_reg;
+		ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
+
+		ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;
+
+		ct->regs.enable = INTC_MIR_CLEAR0 + 32 * i;
+		ct->regs.disable = INTC_MIR_SET0 + 32 * i;
+	}
+
+	return 0;
+}
+
+static void __init omap_alloc_gc_legacy(void __iomem *base,
+		unsigned int irq_start, unsigned int num)
+{
+	struct irq_chip_generic *gc;
+	struct irq_chip_type *ct;
+
+	gc = irq_alloc_generic_chip("INTC", 1, irq_start, base,
+			handle_level_irq);
+	ct = gc->chip_types;
+	ct->chip.irq_ack = omap_mask_ack_irq;
+	ct->chip.irq_mask = irq_gc_mask_disable_reg;
+	ct->chip.irq_unmask = irq_gc_unmask_enable_reg;
+	ct->chip.flags |= IRQCHIP_SKIP_SET_WAKE;
+
+	ct->regs.enable = INTC_MIR_CLEAR0;
+	ct->regs.disable = INTC_MIR_SET0;
+	irq_setup_generic_chip(gc, IRQ_MSK(num), IRQ_GC_INIT_MASK_CACHE,
+			IRQ_NOREQUEST | IRQ_NOPROBE, 0);
+}
+
+static int __init omap_init_irq_of(struct device_node *node)
+{
+	int ret;
+
+	omap_irq_base = of_iomap(node, 0);
+	if (WARN_ON(!omap_irq_base))
+		return -ENOMEM;
+
+	domain = irq_domain_add_linear(node, omap_nr_irqs,
+			&irq_generic_chip_ops, NULL);
+
+	omap_irq_soft_reset();
+
+	ret = omap_alloc_gc_of(domain, omap_irq_base);
+	if (ret < 0)
+		irq_domain_remove(domain);
+
+	return ret;
+}
+
+static int __init omap_init_irq_legacy(u32 base, struct device_node *node)
+{
+	int j, irq_base;
+
+	omap_irq_base = ioremap(base, SZ_4K);
+	if (WARN_ON(!omap_irq_base))
+		return -ENOMEM;
+
+	irq_base = irq_alloc_descs(-1, 0, omap_nr_irqs, 0);
+	if (irq_base < 0) {
+		pr_warn("Couldn't allocate IRQ numbers\n");
+		irq_base = 0;
+	}
+
+	domain = irq_domain_add_legacy(node, omap_nr_irqs, irq_base, 0,
+			&irq_domain_simple_ops, NULL);
+
+	omap_irq_soft_reset();
+
+	for (j = 0; j < omap_nr_irqs; j += 32)
+		omap_alloc_gc_legacy(omap_irq_base + j, j + irq_base, 32);
+
+	return 0;
+}
+
+static void __init omap_irq_enable_protection(void)
+{
+	u32 reg;
+
+	reg = intc_readl(INTC_PROTECTION);
+	reg |= INTC_PROTECTION_ENABLE;
+	intc_writel(INTC_PROTECTION, reg);
+}
+
+static int __init omap_init_irq(u32 base, struct device_node *node)
+{
+	int ret;
+
+	/*
+	 * FIXME legacy OMAP DMA driver sitting under arch/arm/plat-omap/dma.c
+	 * depends is still not ready for linear IRQ domains; because of that
+	 * we need to temporarily "blacklist" OMAP2 and OMAP3 devices from using
+	 * linear IRQ Domain until that driver is finally fixed.
+	 */
+	if (of_device_is_compatible(node, "ti,omap2-intc") ||
+			of_device_is_compatible(node, "ti,omap3-intc")) {
+		struct resource res;
+
+		if (of_address_to_resource(node, 0, &res))
+			return -ENOMEM;
+
+		base = res.start;
+		ret = omap_init_irq_legacy(base, node);
+	} else if (node) {
+		ret = omap_init_irq_of(node);
+	} else {
+		ret = omap_init_irq_legacy(base, NULL);
+	}
+
+	if (ret == 0)
+		omap_irq_enable_protection();
+
+	return ret;
+}
+
+static asmlinkage void __exception_irq_entry
+omap_intc_handle_irq(struct pt_regs *regs)
+{
+	extern unsigned long irq_err_count;
+	u32 irqnr;
+
+	irqnr = intc_readl(INTC_SIR);
+
+	/*
+	 * A spurious IRQ can result if interrupt that triggered the
+	 * sorting is no longer active during the sorting (10 INTC
+	 * functional clock cycles after interrupt assertion). Or a
+	 * change in interrupt mask affected the result during sorting
+	 * time. There is no special handling required except ignoring
+	 * the SIR register value just read and retrying.
+	 * See section 6.2.5 of AM335x TRM Literature Number: SPRUH73K
+	 *
+	 * Many a times, a spurious interrupt situation has been fixed
+	 * by adding a flush for the posted write acking the IRQ in
+	 * the device driver. Typically, this is going be the device
+	 * driver whose interrupt was handled just before the spurious
+	 * IRQ occurred. Pay attention to those device drivers if you
+	 * run into hitting the spurious IRQ condition below.
+	 */
+	if (unlikely((irqnr & SPURIOUSIRQ_MASK) == SPURIOUSIRQ_MASK)) {
+		pr_err_once("%s: spurious irq!\n", __func__);
+		irq_err_count++;
+		omap_ack_irq(NULL);
+		return;
+	}
+
+	irqnr &= ACTIVEIRQ_MASK;
+	handle_domain_irq(domain, irqnr, regs);
+}
+
+static int __init intc_of_init(struct device_node *node,
+			     struct device_node *parent)
+{
+	int ret;
+
+	omap_nr_pending = 3;
+	omap_nr_irqs = 96;
+
+	if (WARN_ON(!node))
+		return -ENODEV;
+
+	if (of_device_is_compatible(node, "ti,dm814-intc") ||
+	    of_device_is_compatible(node, "ti,dm816-intc") ||
+	    of_device_is_compatible(node, "ti,am33xx-intc")) {
+		omap_nr_irqs = 128;
+		omap_nr_pending = 4;
+	}
+
+	ret = omap_init_irq(-1, of_node_get(node));
+	if (ret < 0)
+		return ret;
+
+	set_handle_irq(omap_intc_handle_irq);
+
+	return 0;
+}
+
+IRQCHIP_DECLARE(omap2_intc, "ti,omap2-intc", intc_of_init);
+IRQCHIP_DECLARE(omap3_intc, "ti,omap3-intc", intc_of_init);
+IRQCHIP_DECLARE(dm814x_intc, "ti,dm814-intc", intc_of_init);
+IRQCHIP_DECLARE(dm816x_intc, "ti,dm816-intc", intc_of_init);
+IRQCHIP_DECLARE(am33xx_intc, "ti,am33xx-intc", intc_of_init);