1 files changed, 295 insertions, 0 deletions
diff --git a/arch/mips/kernel/irq-gic.c b/arch/mips/kernel/irq-gic.c
new file mode 100644
index 0000000..f0a4bb1
--- /dev/null
+++ b/arch/mips/kernel/irq-gic.c
@@ -0,0 +1,295 @@
+#undef DEBUG
+
+#include <linux/bitmap.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+#include <asm/gic.h>
+#include <asm/gcmpregs.h>
+#include <asm/mips-boards/maltaint.h>
+#include <asm/irq.h>
+#include <linux/hardirq.h>
+#include <asm-generic/bitops/find.h>
+
+
+static unsigned long _gic_base;
+static unsigned int _irqbase, _mapsize, numvpes, numintrs;
+static struct gic_intr_map *_intrmap;
+
+static struct gic_pcpu_mask pcpu_masks[NR_CPUS];
+static struct gic_pending_regs pending_regs[NR_CPUS];
+static struct gic_intrmask_regs intrmask_regs[NR_CPUS];
+
+#define gic_wedgeb2bok 0	/*
+				 * Can GIC handle b2b writes to wedge register?
+				 */
+#if gic_wedgeb2bok == 0
+static DEFINE_SPINLOCK(gic_wedgeb2b_lock);
+#endif
+
+void gic_send_ipi(unsigned int intr)
+{
+#if gic_wedgeb2bok == 0
+	unsigned long flags;
+#endif
+	pr_debug("CPU%d: %s status %08x\n", smp_processor_id(), __func__,
+		 read_c0_status());
+	if (!gic_wedgeb2bok)
+		spin_lock_irqsave(&gic_wedgeb2b_lock, flags);
+	GICWRITE(GIC_REG(SHARED, GIC_SH_WEDGE), 0x80000000 | intr);
+	if (!gic_wedgeb2bok) {
+		(void) GIC_REG(SHARED, GIC_SH_CONFIG);
+		spin_unlock_irqrestore(&gic_wedgeb2b_lock, flags);
+	}
+}
+
+/* This is Malta specific and needs to be exported */
+static void vpe_local_setup(unsigned int numvpes)
+{
+	int i;
+	unsigned long timer_interrupt = 5, perf_interrupt = 5;
+	unsigned int vpe_ctl;
+
+	/*
+	 * Setup the default performance counter timer interrupts
+	 * for all VPEs
+	 */
+	for (i = 0; i < numvpes; i++) {
+		GICWRITE(GIC_REG(VPE_LOCAL, GIC_VPE_OTHER_ADDR), i);
+
+		/* Are Interrupts locally routable? */
+		GICREAD(GIC_REG(VPE_OTHER, GIC_VPE_CTL), vpe_ctl);
+		if (vpe_ctl & GIC_VPE_CTL_TIMER_RTBL_MSK)
+			GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_TIMER_MAP),
+				 GIC_MAP_TO_PIN_MSK | timer_interrupt);
+
+		if (vpe_ctl & GIC_VPE_CTL_PERFCNT_RTBL_MSK)
+			GICWRITE(GIC_REG(VPE_OTHER, GIC_VPE_PERFCTR_MAP),
+				 GIC_MAP_TO_PIN_MSK | perf_interrupt);
+	}
+}
+
+unsigned int gic_get_int(void)
+{
+	unsigned int i;
+	unsigned long *pending, *intrmask, *pcpu_mask;
+	unsigned long *pending_abs, *intrmask_abs;
+
+	/* Get per-cpu bitmaps */
+	pending = pending_regs[smp_processor_id()].pending;
+	intrmask = intrmask_regs[smp_processor_id()].intrmask;
+	pcpu_mask = pcpu_masks[smp_processor_id()].pcpu_mask;
+
+	pending_abs = (unsigned long *) GIC_REG_ABS_ADDR(SHARED,
+							 GIC_SH_PEND_31_0_OFS);
+	intrmask_abs = (unsigned long *) GIC_REG_ABS_ADDR(SHARED,
+							  GIC_SH_MASK_31_0_OFS);
+
+	for (i = 0; i < BITS_TO_LONGS(GIC_NUM_INTRS); i++) {
+		GICREAD(*pending_abs, pending[i]);
+		GICREAD(*intrmask_abs, intrmask[i]);
+		pending_abs++;
+		intrmask_abs++;
+	}
+
+	bitmap_and(pending, pending, intrmask, GIC_NUM_INTRS);
+	bitmap_and(pending, pending, pcpu_mask, GIC_NUM_INTRS);
+
+	i = find_first_bit(pending, GIC_NUM_INTRS);
+
+	pr_debug("CPU%d: %s pend=%d\n", smp_processor_id(), __func__, i);
+
+	return i;
+}
+
+static unsigned int gic_irq_startup(unsigned int irq)
+{
+	pr_debug("CPU%d: %s: irq%d\n", smp_processor_id(), __func__, irq);
+	irq -= _irqbase;
+	/* FIXME: this is wrong for !GICISWORDLITTLEENDIAN */
+	GICWRITE(GIC_REG_ADDR(SHARED, (GIC_SH_SMASK_31_0_OFS + (irq / 32))),
+		 1 << (irq % 32));
+	return 0;
+}
+
+static void gic_irq_ack(unsigned int irq)
+{
+#if gic_wedgeb2bok == 0
+	unsigned long flags;
+#endif
+	pr_debug("CPU%d: %s: irq%d\n", smp_processor_id(), __func__, irq);
+	irq -= _irqbase;
+	GICWRITE(GIC_REG_ADDR(SHARED, (GIC_SH_RMASK_31_0_OFS + (irq / 32))),
+		 1 << (irq % 32));
+
+	if (_intrmap[irq].trigtype == GIC_TRIG_EDGE) {
+		if (!gic_wedgeb2bok)
+			spin_lock_irqsave(&gic_wedgeb2b_lock, flags);
+		GICWRITE(GIC_REG(SHARED, GIC_SH_WEDGE), irq);
+		if (!gic_wedgeb2bok) {
+			(void) GIC_REG(SHARED, GIC_SH_CONFIG);
+			spin_unlock_irqrestore(&gic_wedgeb2b_lock, flags);
+		}
+	}
+}
+
+static void gic_mask_irq(unsigned int irq)
+{
+	pr_debug("CPU%d: %s: irq%d\n", smp_processor_id(), __func__, irq);
+	irq -= _irqbase;
+	/* FIXME: this is wrong for !GICISWORDLITTLEENDIAN */
+	GICWRITE(GIC_REG_ADDR(SHARED, (GIC_SH_RMASK_31_0_OFS + (irq / 32))),
+		 1 << (irq % 32));
+}
+
+static void gic_unmask_irq(unsigned int irq)
+{
+	pr_debug("CPU%d: %s: irq%d\n", smp_processor_id(), __func__, irq);
+	irq -= _irqbase;
+	/* FIXME: this is wrong for !GICISWORDLITTLEENDIAN */
+	GICWRITE(GIC_REG_ADDR(SHARED, (GIC_SH_SMASK_31_0_OFS + (irq / 32))),
+		 1 << (irq % 32));
+}
+
+#ifdef CONFIG_SMP
+
+static DEFINE_SPINLOCK(gic_lock);
+
+static void gic_set_affinity(unsigned int irq, cpumask_t cpumask)
+{
+	cpumask_t	tmp = CPU_MASK_NONE;
+	unsigned long	flags;
+	int		i;
+
+	pr_debug(KERN_DEBUG "%s called\n", __func__);
+	irq -= _irqbase;
+
+	cpus_and(tmp, cpumask, cpu_online_map);
+	if (cpus_empty(tmp))
+		return;
+
+	/* Assumption : cpumask refers to a single CPU */
+	spin_lock_irqsave(&gic_lock, flags);
+	for (;;) {
+		/* Re-route this IRQ */
+		GIC_SH_MAP_TO_VPE_SMASK(irq, first_cpu(tmp));
+
+		/*
+		 * FIXME: assumption that _intrmap is ordered and has no holes
+		 */
+
+		/* Update the intr_map */
+		_intrmap[irq].cpunum = first_cpu(tmp);
+
+		/* Update the pcpu_masks */
+		for (i = 0; i < NR_CPUS; i++)
+			clear_bit(irq, pcpu_masks[i].pcpu_mask);
+		set_bit(irq, pcpu_masks[first_cpu(tmp)].pcpu_mask);
+
+	}
+	irq_desc[irq].affinity = cpumask;
+	spin_unlock_irqrestore(&gic_lock, flags);
+
+}
+#endif
+
+static struct irq_chip gic_irq_controller = {
+	.name		=	"MIPS GIC",
+	.startup	=	gic_irq_startup,
+	.ack		=	gic_irq_ack,
+	.mask		=	gic_mask_irq,
+	.mask_ack	=	gic_mask_irq,
+	.unmask		=	gic_unmask_irq,
+	.eoi		=	gic_unmask_irq,
+#ifdef CONFIG_SMP
+	.set_affinity	=	gic_set_affinity,
+#endif
+};
+
+static void __init setup_intr(unsigned int intr, unsigned int cpu,
+	unsigned int pin, unsigned int polarity, unsigned int trigtype)
+{
+	/* Setup Intr to Pin mapping */
+	if (pin & GIC_MAP_TO_NMI_MSK) {
+		GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(intr)), pin);
+		/* FIXME: hack to route NMI to all cpu's */
+		for (cpu = 0; cpu < NR_CPUS; cpu += 32) {
+			GICWRITE(GIC_REG_ADDR(SHARED,
+					  GIC_SH_MAP_TO_VPE_REG_OFF(intr, cpu)),
+				 0xffffffff);
+		}
+	} else {
+		GICWRITE(GIC_REG_ADDR(SHARED, GIC_SH_MAP_TO_PIN(intr)),
+			 GIC_MAP_TO_PIN_MSK | pin);
+		/* Setup Intr to CPU mapping */
+		GIC_SH_MAP_TO_VPE_SMASK(intr, cpu);
+	}
+
+	/* Setup Intr Polarity */
+	GIC_SET_POLARITY(intr, polarity);
+
+	/* Setup Intr Trigger Type */
+	GIC_SET_TRIGGER(intr, trigtype);
+
+	/* Init Intr Masks */
+	GIC_SET_INTR_MASK(intr, 0);
+}
+
+static void __init gic_basic_init(void)
+{
+	unsigned int i, cpu;
+
+	/* Setup defaults */
+	for (i = 0; i < GIC_NUM_INTRS; i++) {
+		GIC_SET_POLARITY(i, GIC_POL_POS);
+		GIC_SET_TRIGGER(i, GIC_TRIG_LEVEL);
+		GIC_SET_INTR_MASK(i, 0);
+	}
+
+	/* Setup specifics */
+	for (i = 0; i < _mapsize; i++) {
+		cpu = _intrmap[i].cpunum;
+		if (cpu == X)
+			continue;
+
+		setup_intr(_intrmap[i].intrnum,
+				_intrmap[i].cpunum,
+				_intrmap[i].pin,
+				_intrmap[i].polarity,
+				_intrmap[i].trigtype);
+		/* Initialise per-cpu Interrupt software masks */
+		if (_intrmap[i].ipiflag)
+			set_bit(_intrmap[i].intrnum, pcpu_masks[cpu].pcpu_mask);
+	}
+
+	vpe_local_setup(numvpes);
+
+	for (i = _irqbase; i < (_irqbase + numintrs); i++)
+		set_irq_chip(i, &gic_irq_controller);
+}
+
+void __init gic_init(unsigned long gic_base_addr,
+		     unsigned long gic_addrspace_size,
+		     struct gic_intr_map *intr_map, unsigned int intr_map_size,
+		     unsigned int irqbase)
+{
+	unsigned int gicconfig;
+
+	_gic_base = (unsigned long) ioremap_nocache(gic_base_addr,
+						    gic_addrspace_size);
+	_irqbase = irqbase;
+	_intrmap = intr_map;
+	_mapsize = intr_map_size;
+
+	GICREAD(GIC_REG(SHARED, GIC_SH_CONFIG), gicconfig);
+	numintrs = (gicconfig & GIC_SH_CONFIG_NUMINTRS_MSK) >>
+		   GIC_SH_CONFIG_NUMINTRS_SHF;
+	numintrs = ((numintrs + 1) * 8);
+
+	numvpes = (gicconfig & GIC_SH_CONFIG_NUMVPES_MSK) >>
+		  GIC_SH_CONFIG_NUMVPES_SHF;
+
+	pr_debug("%s called\n", __func__);
+
+	gic_basic_init();
+}