[MIPS] PMC MSP71xx core platform

Patch to add core platform support for the PMC-Sierra MSP71xx devices.

Signed-off-by: Marc St-Jean <Marc_St-Jean@pmc-sierra.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/pmc-sierra/msp71xx/msp_irq_slp.c b/arch/mips/pmc-sierra/msp71xx/msp_irq_slp.c
new file mode 100644
index 0000000..f5f1b8d
--- /dev/null
+++ b/arch/mips/pmc-sierra/msp71xx/msp_irq_slp.c
@@ -0,0 +1,109 @@
+/*
+ * This file define the irq handler for MSP SLM subsystem interrupts.
+ *
+ * Copyright 2005-2006 PMC-Sierra, Inc, derived from irq_cpu.c
+ * Author: Andrew Hughes, Andrew_Hughes@pmc-sierra.com
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+
+#include <asm/mipsregs.h>
+#include <asm/system.h>
+
+#include <msp_slp_int.h>
+#include <msp_regs.h>
+
+static inline void unmask_msp_slp_irq(unsigned int irq)
+{
+	/* check for PER interrupt range */
+	if (irq < MSP_PER_INTBASE)
+		*SLP_INT_MSK_REG |= (1 << (irq - MSP_SLP_INTBASE));
+	else
+		*PER_INT_MSK_REG |= (1 << (irq - MSP_PER_INTBASE));
+}
+
+static inline void mask_msp_slp_irq(unsigned int irq)
+{
+	/* check for PER interrupt range */
+	if (irq < MSP_PER_INTBASE)
+		*SLP_INT_MSK_REG &= ~(1 << (irq - MSP_SLP_INTBASE));
+	else
+		*PER_INT_MSK_REG &= ~(1 << (irq - MSP_PER_INTBASE));
+}
+
+/*
+ * While we ack the interrupt interrupts are disabled and thus we don't need
+ * to deal with concurrency issues.  Same for msp_slp_irq_end.
+ */
+static inline void ack_msp_slp_irq(unsigned int irq)
+{
+	mask_slp_irq(irq);
+
+	/*
+	 * only really necessary for 18, 16-14 and sometimes 3:0 (since
+	 * these can be edge sensitive) but it doesn't hurt  for the others.
+	 */
+
+	/* check for PER interrupt range */
+	if (irq < MSP_PER_INTBASE)
+		*SLP_INT_STS_REG = (1 << (irq - MSP_SLP_INTBASE));
+	else
+		*PER_INT_STS_REG = (1 << (irq - MSP_PER_INTBASE));
+}
+
+static struct irq_chip msp_slp_irq_controller = {
+	.name = "MSP_SLP",
+	.ack = ack_msp_slp_irq,
+	.mask = ack_msp_slp_irq,
+	.mask_ack = ack_msp_slp_irq,
+	.unmask = unmask_msp_slp_irq,
+};
+
+void __init msp_slp_irq_init(void)
+{
+	int i;
+
+	/* Mask/clear interrupts. */
+	*SLP_INT_MSK_REG = 0x00000000;
+	*PER_INT_MSK_REG = 0x00000000;
+	*SLP_INT_STS_REG = 0xFFFFFFFF;
+	*PER_INT_STS_REG = 0xFFFFFFFF;
+
+	/* initialize all the IRQ descriptors */
+	for (i = MSP_SLP_INTBASE; i < MSP_PER_INTBASE + 32; i++)
+		set_irq_chip_and_handler(i, &msp_slp_irq_controller
+					 handle_level_irq);
+}
+
+void msp_slp_irq_dispatch(void)
+{
+	u32 pending;
+	int intbase;
+
+	intbase = MSP_SLP_INTBASE;
+	pending = *SLP_INT_STS_REG & *SLP_INT_MSK_REG;
+
+	/* check for PER interrupt */
+	if (pending == (1 << (MSP_INT_PER - MSP_SLP_INTBASE))) {
+		intbase = MSP_PER_INTBASE;
+		pending = *PER_INT_STS_REG & *PER_INT_MSK_REG;
+	}
+
+	/* check for spurious interrupt */
+	if (pending == 0x00000000) {
+		printk(KERN_ERR "Spurious %s interrupt?\n",
+			(intbase == MSP_SLP_INTBASE) ? "SLP" : "PER");
+		return;
+	}
+
+	/* dispatch the irq */
+	do_IRQ(ffs(pending) + intbase - 1);
+}