mxc: TrustZone interrupt controller (TZIC) for Freescale i.MX5 family

Freescale i.MX51 processor uses a new interrupt controller. Add
driver for TrustZone Interrupt Controller

Signed-off-by: Amit Kucheria <amit.kucheria@canonical.com>

1 files changed, 172 insertions, 0 deletions

diff --git a/arch/arm/plat-mxc/tzic.c b/arch/arm/plat-mxc/tzic.c
new file mode 100644
index 000000000000..afa6709db0b3
--- /dev/null
+++ b/arch/arm/plat-mxc/tzic.c
@@ -0,0 +1,172 @@
+/*
+ * Copyright 2004-2009 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+
+#include <asm/mach/irq.h>
+
+#include <mach/hardware.h>
+
+/*
+ *****************************************
+ * TZIC Registers                        *
+ *****************************************
+ */
+
+#define TZIC_INTCNTL	0x0000	/* Control register */
+#define TZIC_INTTYPE	0x0004	/* Controller Type register */
+#define TZIC_IMPID	0x0008	/* Distributor Implementer Identification */
+#define TZIC_PRIOMASK	0x000C	/* Priority Mask Reg */
+#define TZIC_SYNCCTRL	0x0010	/* Synchronizer Control register */
+#define TZIC_DSMINT	0x0014	/* DSM interrupt Holdoffregister */
+#define TZIC_INTSEC0(i)	(0x0080 + ((i) << 2)) /* Interrupt Security Reg 0 */
+#define TZIC_ENSET0(i)	(0x0100 + ((i) << 2)) /* Enable Set Reg 0 */
+#define TZIC_ENCLEAR0(i) (0x0180 + ((i) << 2)) /* Enable Clear Reg 0 */
+#define TZIC_SRCSET0	0x0200	/* Source Set Register 0 */
+#define TZIC_SRCCLAR0	0x0280	/* Source Clear Register 0 */
+#define TZIC_PRIORITY0	0x0400	/* Priority Register 0 */
+#define TZIC_PND0	0x0D00	/* Pending Register 0 */
+#define TZIC_HIPND0	0x0D80	/* High Priority Pending Register */
+#define TZIC_WAKEUP0(i)	(0x0E00 + ((i) << 2))	/* Wakeup Config Register */
+#define TZIC_SWINT	0x0F00	/* Software Interrupt Rigger Register */
+#define TZIC_ID0	0x0FD0	/* Indentification Register 0 */
+
+void __iomem *tzic_base; /* Used as irq controller base in entry-macro.S */
+
+/**
+ * tzic_mask_irq() - Disable interrupt number "irq" in the TZIC
+ *
+ * @param  irq          interrupt source number
+ */
+static void tzic_mask_irq(unsigned int irq)
+{
+	int index, off;
+
+	index = irq >> 5;
+	off = irq & 0x1F;
+	__raw_writel(1 << off, tzic_base + TZIC_ENCLEAR0(index));
+}
+
+/**
+ * tzic_unmask_irq() - Enable interrupt number "irq" in the TZIC
+ *
+ * @param  irq          interrupt source number
+ */
+static void tzic_unmask_irq(unsigned int irq)
+{
+	int index, off;
+
+	index = irq >> 5;
+	off = irq & 0x1F;
+	__raw_writel(1 << off, tzic_base + TZIC_ENSET0(index));
+}
+
+static unsigned int wakeup_intr[4];
+
+/**
+ * tzic_set_wake_irq() - Set interrupt number "irq" in the TZIC as a wake-up source.
+ *
+ * @param  irq          interrupt source number
+ * @param  enable       enable as wake-up if equal to non-zero
+ * 			disble as wake-up if equal to zero
+ *
+ * @return       This function returns 0 on success.
+ */
+static int tzic_set_wake_irq(unsigned int irq, unsigned int enable)
+{
+	unsigned int index, off;
+
+	index = irq >> 5;
+	off = irq & 0x1F;
+
+	if (index > 3)
+		return -EINVAL;
+
+	if (enable)
+		wakeup_intr[index] |= (1 << off);
+	else
+		wakeup_intr[index] &= ~(1 << off);
+
+	return 0;
+}
+
+static struct irq_chip mxc_tzic_chip = {
+	.name = "MXC_TZIC",
+	.ack = tzic_mask_irq,
+	.mask = tzic_mask_irq,
+	.unmask = tzic_unmask_irq,
+	.set_wake = tzic_set_wake_irq,
+};
+
+/*
+ * This function initializes the TZIC hardware and disables all the
+ * interrupts. It registers the interrupt enable and disable functions
+ * to the kernel for each interrupt source.
+ */
+void __init tzic_init_irq(void __iomem *irqbase)
+{
+	int i;
+
+	tzic_base = irqbase;
+	/* put the TZIC into the reset value with
+	 * all interrupts disabled
+	 */
+	i = __raw_readl(tzic_base + TZIC_INTCNTL);
+
+	__raw_writel(0x80010001, tzic_base + TZIC_INTCNTL);
+	__raw_writel(0x1f, tzic_base + TZIC_PRIOMASK);
+	__raw_writel(0x02, tzic_base + TZIC_SYNCCTRL);
+
+	for (i = 0; i < 4; i++)
+		__raw_writel(0xFFFFFFFF, tzic_base + TZIC_INTSEC0(i));
+
+	/* disable all interrupts */
+	for (i = 0; i < 4; i++)
+		__raw_writel(0xFFFFFFFF, tzic_base + TZIC_ENCLEAR0(i));
+
+	/* all IRQ no FIQ Warning :: No selection */
+
+	for (i = 0; i < MXC_INTERNAL_IRQS; i++) {
+		set_irq_chip(i, &mxc_tzic_chip);
+		set_irq_handler(i, handle_level_irq);
+		set_irq_flags(i, IRQF_VALID);
+	}
+
+	pr_info("TrustZone Interrupt Controller (TZIC) initialized\n");
+}
+
+/**
+ * tzic_enable_wake() - enable wakeup interrupt
+ *
+ * @param is_idle		1 if called in idle loop (ENSET0 register);
+ *				0 to be used when called from low power entry
+ * @return			0 if successful; non-zero otherwise
+ */
+int tzic_enable_wake(int is_idle)
+{
+	unsigned int i, v;
+
+	__raw_writel(1, tzic_base + TZIC_DSMINT);
+	if (unlikely(__raw_readl(tzic_base + TZIC_DSMINT) == 0))
+		return -EAGAIN;
+
+	for (i = 0; i < 4; i++) {
+		v = is_idle ? __raw_readl(TZIC_ENSET0(i)) : wakeup_intr[i];
+		__raw_writel(v, TZIC_WAKEUP0(i));
+	}
+
+	return 0;
+}