irqchip: sunxi: Rename sunxi to sun4i

During the introduction of the Allwinner SoC platforms, sunxi was
initially meant as a generic name for all the variants of the Allwinner
SoC.

It was ok at the time of the support of only the A10 and A13 that
looks pretty much the same, but it's beginning to be troublesome with
the future addition of the Allwinner A31 (sun6i) that is quite
different, and would introduce some weird logic, where sunxi would
actually mean in some case sun4i and sun5i but without sun6i...

Moreover, it makes the compatible strings naming scheme not consistent
with other architectures, where usually for this kind of compability, we
just use the oldest SoC name that has this IP, so let's do just this.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

1 files changed, 149 insertions, 0 deletions

diff --git a/drivers/irqchip/irq-sun4i.c b/drivers/irqchip/irq-sun4i.c
new file mode 100644
index 000000000000..b66d4ae06898
--- /dev/null
+++ b/drivers/irqchip/irq-sun4i.c
@@ -0,0 +1,149 @@
+/*
+ * Allwinner A1X SoCs IRQ chip driver.
+ *
+ * Copyright (C) 2012 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on code from
+ * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
+ * Benn Huang <benn@allwinnertech.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <asm/exception.h>
+#include <asm/mach/irq.h>
+
+#include "irqchip.h"
+
+#define SUN4I_IRQ_VECTOR_REG		0x00
+#define SUN4I_IRQ_PROTECTION_REG	0x08
+#define SUN4I_IRQ_NMI_CTRL_REG		0x0c
+#define SUN4I_IRQ_PENDING_REG(x)	(0x10 + 0x4 * x)
+#define SUN4I_IRQ_FIQ_PENDING_REG(x)	(0x20 + 0x4 * x)
+#define SUN4I_IRQ_ENABLE_REG(x)		(0x40 + 0x4 * x)
+#define SUN4I_IRQ_MASK_REG(x)		(0x50 + 0x4 * x)
+
+static void __iomem *sun4i_irq_base;
+static struct irq_domain *sun4i_irq_domain;
+
+static asmlinkage void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs);
+
+void sun4i_irq_ack(struct irq_data *irqd)
+{
+	unsigned int irq = irqd_to_hwirq(irqd);
+	unsigned int irq_off = irq % 32;
+	int reg = irq / 32;
+	u32 val;
+
+	val = readl(sun4i_irq_base + SUN4I_IRQ_PENDING_REG(reg));
+	writel(val | (1 << irq_off),
+	       sun4i_irq_base + SUN4I_IRQ_PENDING_REG(reg));
+}
+
+static void sun4i_irq_mask(struct irq_data *irqd)
+{
+	unsigned int irq = irqd_to_hwirq(irqd);
+	unsigned int irq_off = irq % 32;
+	int reg = irq / 32;
+	u32 val;
+
+	val = readl(sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
+	writel(val & ~(1 << irq_off),
+	       sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
+}
+
+static void sun4i_irq_unmask(struct irq_data *irqd)
+{
+	unsigned int irq = irqd_to_hwirq(irqd);
+	unsigned int irq_off = irq % 32;
+	int reg = irq / 32;
+	u32 val;
+
+	val = readl(sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
+	writel(val | (1 << irq_off),
+	       sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
+}
+
+static struct irq_chip sun4i_irq_chip = {
+	.name		= "sun4i_irq",
+	.irq_ack	= sun4i_irq_ack,
+	.irq_mask	= sun4i_irq_mask,
+	.irq_unmask	= sun4i_irq_unmask,
+};
+
+static int sun4i_irq_map(struct irq_domain *d, unsigned int virq,
+			 irq_hw_number_t hw)
+{
+	irq_set_chip_and_handler(virq, &sun4i_irq_chip,
+				 handle_level_irq);
+	set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
+
+	return 0;
+}
+
+static struct irq_domain_ops sun4i_irq_ops = {
+	.map = sun4i_irq_map,
+	.xlate = irq_domain_xlate_onecell,
+};
+
+static int __init sun4i_of_init(struct device_node *node,
+				struct device_node *parent)
+{
+	sun4i_irq_base = of_iomap(node, 0);
+	if (!sun4i_irq_base)
+		panic("%s: unable to map IC registers\n",
+			node->full_name);
+
+	/* Disable all interrupts */
+	writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(0));
+	writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(1));
+	writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(2));
+
+	/* Mask all the interrupts */
+	writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(0));
+	writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(1));
+	writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(2));
+
+	/* Clear all the pending interrupts */
+	writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0));
+	writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(1));
+	writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(2));
+
+	/* Enable protection mode */
+	writel(0x01, sun4i_irq_base + SUN4I_IRQ_PROTECTION_REG);
+
+	/* Configure the external interrupt source type */
+	writel(0x00, sun4i_irq_base + SUN4I_IRQ_NMI_CTRL_REG);
+
+	sun4i_irq_domain = irq_domain_add_linear(node, 3 * 32,
+						 &sun4i_irq_ops, NULL);
+	if (!sun4i_irq_domain)
+		panic("%s: unable to create IRQ domain\n", node->full_name);
+
+	set_handle_irq(sun4i_handle_irq);
+
+	return 0;
+}
+IRQCHIP_DECLARE(allwinner_sun4i_ic, "allwinner,sun4i-ic", sun4i_of_init);
+
+static asmlinkage void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs)
+{
+	u32 irq, hwirq;
+
+	hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
+	while (hwirq != 0) {
+		irq = irq_find_mapping(sun4i_irq_domain, hwirq);
+		handle_IRQ(irq, regs);
+		hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
+	}
+}