[POWERPC] Add new interrupt mapping core and change platforms to use it

This adds the new irq remapper core and removes the old one.  Because
there are some fundamental conflicts with the old code, like the value
of NO_IRQ which I'm now setting to 0 (as per discussions with Linus),
etc..., this commit also changes the relevant platform and driver code
over to use the new remapper (so as not to cause difficulties later
in bisecting).

This patch removes the old pre-parsing of the open firmware interrupt
tree along with all the bogus assumptions it made to try to renumber
interrupts according to the platform. This is all to be handled by the
new code now.

For the pSeries XICS interrupt controller, a single remapper host is
created for the whole machine regardless of how many interrupt
presentation and source controllers are found, and it's set to match
any device node that isn't a 8259.  That works fine on pSeries and
avoids having to deal with some of the complexities of split source
controllers vs. presentation controllers in the pSeries device trees.

The powerpc i8259 PIC driver now always requests the legacy interrupt
range. It also has the feature of being able to match any device node
(including NULL) if passed no device node as an input. That will help
porting over platforms with broken device-trees like Pegasos who don't
have a proper interrupt tree.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/cell/spu_base.c b/arch/powerpc/platforms/cell/spu_base.c
index 656c1ef..5d2313a 100644
--- a/arch/powerpc/platforms/cell/spu_base.c
+++ b/arch/powerpc/platforms/cell/spu_base.c
@@ -264,51 +264,57 @@
 	return stat ? IRQ_HANDLED : IRQ_NONE;
 }
 
-static int
-spu_request_irqs(struct spu *spu)
+static int spu_request_irqs(struct spu *spu)
 {
-	int ret;
-	int irq_base;
+	int ret = 0;
 
-	irq_base = IIC_NODE_STRIDE * spu->node + IIC_SPE_OFFSET;
+	if (spu->irqs[0] != NO_IRQ) {
+		snprintf(spu->irq_c0, sizeof (spu->irq_c0), "spe%02d.0",
+			 spu->number);
+		ret = request_irq(spu->irqs[0], spu_irq_class_0,
+				  IRQF_DISABLED,
+				  spu->irq_c0, spu);
+		if (ret)
+			goto bail0;
+	}
+	if (spu->irqs[1] != NO_IRQ) {
+		snprintf(spu->irq_c1, sizeof (spu->irq_c1), "spe%02d.1",
+			 spu->number);
+		ret = request_irq(spu->irqs[1], spu_irq_class_1,
+				  IRQF_DISABLED,
+				  spu->irq_c1, spu);
+		if (ret)
+			goto bail1;
+	}
+	if (spu->irqs[2] != NO_IRQ) {
+		snprintf(spu->irq_c2, sizeof (spu->irq_c2), "spe%02d.2",
+			 spu->number);
+		ret = request_irq(spu->irqs[2], spu_irq_class_2,
+				  IRQF_DISABLED,
+				  spu->irq_c2, spu);
+		if (ret)
+			goto bail2;
+	}
+	return 0;
 
-	snprintf(spu->irq_c0, sizeof (spu->irq_c0), "spe%02d.0", spu->number);
-	ret = request_irq(irq_base + spu->isrc,
-		 spu_irq_class_0, IRQF_DISABLED, spu->irq_c0, spu);
-	if (ret)
-		goto out;
-
-	snprintf(spu->irq_c1, sizeof (spu->irq_c1), "spe%02d.1", spu->number);
-	ret = request_irq(irq_base + IIC_CLASS_STRIDE + spu->isrc,
-		 spu_irq_class_1, IRQF_DISABLED, spu->irq_c1, spu);
-	if (ret)
-		goto out1;
-
-	snprintf(spu->irq_c2, sizeof (spu->irq_c2), "spe%02d.2", spu->number);
-	ret = request_irq(irq_base + 2*IIC_CLASS_STRIDE + spu->isrc,
-		 spu_irq_class_2, IRQF_DISABLED, spu->irq_c2, spu);
-	if (ret)
-		goto out2;
-	goto out;
-
-out2:
-	free_irq(irq_base + IIC_CLASS_STRIDE + spu->isrc, spu);
-out1:
-	free_irq(irq_base + spu->isrc, spu);
-out:
+bail2:
+	if (spu->irqs[1] != NO_IRQ)
+		free_irq(spu->irqs[1], spu);
+bail1:
+	if (spu->irqs[0] != NO_IRQ)
+		free_irq(spu->irqs[0], spu);
+bail0:
 	return ret;
 }
 
-static void
-spu_free_irqs(struct spu *spu)
+static void spu_free_irqs(struct spu *spu)
 {
-	int irq_base;
-
-	irq_base = IIC_NODE_STRIDE * spu->node + IIC_SPE_OFFSET;
-
-	free_irq(irq_base + spu->isrc, spu);
-	free_irq(irq_base + IIC_CLASS_STRIDE + spu->isrc, spu);
-	free_irq(irq_base + 2*IIC_CLASS_STRIDE + spu->isrc, spu);
+	if (spu->irqs[0] != NO_IRQ)
+		free_irq(spu->irqs[0], spu);
+	if (spu->irqs[1] != NO_IRQ)
+		free_irq(spu->irqs[1], spu);
+	if (spu->irqs[2] != NO_IRQ)
+		free_irq(spu->irqs[2], spu);
 }
 
 static LIST_HEAD(spu_list);
@@ -559,17 +565,38 @@
 	iounmap((u8 __iomem *)spu->local_store);
 }
 
+/* This function shall be abstracted for HV platforms */
+static int __init spu_map_interrupts(struct spu *spu, struct device_node *np)
+{
+	struct irq_host *host;
+	unsigned int isrc;
+	u32 *tmp;
+
+	host = iic_get_irq_host(spu->node);
+	if (host == NULL)
+		return -ENODEV;
+
+	/* Get the interrupt source from the device-tree */
+	tmp = (u32 *)get_property(np, "isrc", NULL);
+	if (!tmp)
+		return -ENODEV;
+	spu->isrc = isrc = tmp[0];
+
+	/* Now map interrupts of all 3 classes */
+	spu->irqs[0] = irq_create_mapping(host, 0x00 | isrc, 0);
+	spu->irqs[1] = irq_create_mapping(host, 0x10 | isrc, 0);
+	spu->irqs[2] = irq_create_mapping(host, 0x20 | isrc, 0);
+
+	/* Right now, we only fail if class 2 failed */
+	return spu->irqs[2] == NO_IRQ ? -EINVAL : 0;
+}
+
 static int __init spu_map_device(struct spu *spu, struct device_node *node)
 {
 	char *prop;
 	int ret;
 
 	ret = -ENODEV;
-	prop = get_property(node, "isrc", NULL);
-	if (!prop)
-		goto out;
-	spu->isrc = *(unsigned int *)prop;
-
 	spu->name = get_property(node, "name", NULL);
 	if (!spu->name)
 		goto out;
@@ -636,7 +663,8 @@
 		return ret;
 	}
 
-	sysdev_create_file(&spu->sysdev, &attr_isrc);
+	if (spu->isrc != 0)
+		sysdev_create_file(&spu->sysdev, &attr_isrc);
 	sysfs_add_device_to_node(&spu->sysdev, spu->nid);
 
 	return 0;
@@ -668,6 +696,9 @@
 	spu->nid = of_node_to_nid(spe);
 	if (spu->nid == -1)
 		spu->nid = 0;
+	ret = spu_map_interrupts(spu, spe);
+	if (ret)
+		goto out_unmap;
 	spin_lock_init(&spu->register_lock);
 	spu_mfc_sdr_set(spu, mfspr(SPRN_SDR1));
 	spu_mfc_sr1_set(spu, 0x33);