[ARM] 4461/1: MXC platform and i.MX31ADS core support

This patch adds the foundation pieces for
the Freescale MXC platforms, including
i.MX2 and i.MX3 based systems.

The bare-bones MX31 support in this patch
boots to the rootdev panic with 8250 serial
console configured "console=ttyS0,115200".
It assumes that Redboot is the boot loader.

Signed-off-by: Quinn Jensen <quinn.jensen@freescale.com>
Acked-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 83 insertions, 0 deletions

diff --git a/arch/arm/plat-mxc/irq.c b/arch/arm/plat-mxc/irq.c
new file mode 100644
index 0000000..87d253b
--- /dev/null
+++ b/arch/arm/plat-mxc/irq.c
@@ -0,0 +1,83 @@
+/*
+ *  Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/mach/irq.h>
+#include <asm/arch/common.h>
+
+/*!
+ * Disable interrupt number "irq" in the AVIC
+ *
+ * @param  irq          interrupt source number
+ */
+static void mxc_mask_irq(unsigned int irq)
+{
+	__raw_writel(irq, AVIC_INTDISNUM);
+}
+
+/*!
+ * Enable interrupt number "irq" in the AVIC
+ *
+ * @param  irq          interrupt source number
+ */
+static void mxc_unmask_irq(unsigned int irq)
+{
+	__raw_writel(irq, AVIC_INTENNUM);
+}
+
+static struct irq_chip mxc_avic_chip = {
+	.mask_ack = mxc_mask_irq,
+	.mask = mxc_mask_irq,
+	.unmask = mxc_unmask_irq,
+};
+
+/*!
+ * This function initializes the AVIC hardware and disables all the
+ * interrupts. It registers the interrupt enable and disable functions
+ * to the kernel for each interrupt source.
+ */
+void __init mxc_init_irq(void)
+{
+	int i;
+	u32 reg;
+
+	/* put the AVIC into the reset value with
+	 * all interrupts disabled
+	 */
+	__raw_writel(0, AVIC_INTCNTL);
+	__raw_writel(0x1f, AVIC_NIMASK);
+
+	/* disable all interrupts */
+	__raw_writel(0, AVIC_INTENABLEH);
+	__raw_writel(0, AVIC_INTENABLEL);
+
+	/* all IRQ no FIQ */
+	__raw_writel(0, AVIC_INTTYPEH);
+	__raw_writel(0, AVIC_INTTYPEL);
+	for (i = 0; i < MXC_MAX_INT_LINES; i++) {
+		set_irq_chip(i, &mxc_avic_chip);
+		set_irq_handler(i, handle_level_irq);
+		set_irq_flags(i, IRQF_VALID);
+	}
+
+	/* Set WDOG2's interrupt the highest priority level (bit 28-31) */
+	reg = __raw_readl(AVIC_NIPRIORITY6);
+	reg |= (0xF << 28);
+	__raw_writel(reg, AVIC_NIPRIORITY6);
+
+	printk(KERN_INFO "MXC IRQ initialized\n");
+}