1 files changed, 344 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/cell/spider-pic.c b/arch/powerpc/platforms/cell/spider-pic.c
new file mode 100644
index 000000000..11df737c8
--- /dev/null
+++ b/arch/powerpc/platforms/cell/spider-pic.c
@@ -0,0 +1,344 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * External Interrupt Controller on Spider South Bridge
+ *
+ * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
+ *
+ * Author: Arnd Bergmann <arndb@de.ibm.com>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/ioport.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/pgtable.h>
+
+#include <asm/io.h>
+
+#include "interrupt.h"
+
+/* register layout taken from Spider spec, table 7.4-4 */
+enum {
+	TIR_DEN		= 0x004, /* Detection Enable Register */
+	TIR_MSK		= 0x084, /* Mask Level Register */
+	TIR_EDC		= 0x0c0, /* Edge Detection Clear Register */
+	TIR_PNDA	= 0x100, /* Pending Register A */
+	TIR_PNDB	= 0x104, /* Pending Register B */
+	TIR_CS		= 0x144, /* Current Status Register */
+	TIR_LCSA	= 0x150, /* Level Current Status Register A */
+	TIR_LCSB	= 0x154, /* Level Current Status Register B */
+	TIR_LCSC	= 0x158, /* Level Current Status Register C */
+	TIR_LCSD	= 0x15c, /* Level Current Status Register D */
+	TIR_CFGA	= 0x200, /* Setting Register A0 */
+	TIR_CFGB	= 0x204, /* Setting Register B0 */
+			/* 0x208 ... 0x3ff Setting Register An/Bn */
+	TIR_PPNDA	= 0x400, /* Packet Pending Register A */
+	TIR_PPNDB	= 0x404, /* Packet Pending Register B */
+	TIR_PIERA	= 0x408, /* Packet Output Error Register A */
+	TIR_PIERB	= 0x40c, /* Packet Output Error Register B */
+	TIR_PIEN	= 0x444, /* Packet Output Enable Register */
+	TIR_PIPND	= 0x454, /* Packet Output Pending Register */
+	TIRDID		= 0x484, /* Spider Device ID Register */
+	REISTIM		= 0x500, /* Reissue Command Timeout Time Setting */
+	REISTIMEN	= 0x504, /* Reissue Command Timeout Setting */
+	REISWAITEN	= 0x508, /* Reissue Wait Control*/
+};
+
+#define SPIDER_CHIP_COUNT	4
+#define SPIDER_SRC_COUNT	64
+#define SPIDER_IRQ_INVALID	63
+
+struct spider_pic {
+	struct irq_domain		*host;
+	void __iomem		*regs;
+	unsigned int		node_id;
+};
+static struct spider_pic spider_pics[SPIDER_CHIP_COUNT];
+
+static struct spider_pic *spider_irq_data_to_pic(struct irq_data *d)
+{
+	return irq_data_get_irq_chip_data(d);
+}
+
+static void __iomem *spider_get_irq_config(struct spider_pic *pic,
+					   unsigned int src)
+{
+	return pic->regs + TIR_CFGA + 8 * src;
+}
+
+static void spider_unmask_irq(struct irq_data *d)
+{
+	struct spider_pic *pic = spider_irq_data_to_pic(d);
+	void __iomem *cfg = spider_get_irq_config(pic, irqd_to_hwirq(d));
+
+	out_be32(cfg, in_be32(cfg) | 0x30000000u);
+}
+
+static void spider_mask_irq(struct irq_data *d)
+{
+	struct spider_pic *pic = spider_irq_data_to_pic(d);
+	void __iomem *cfg = spider_get_irq_config(pic, irqd_to_hwirq(d));
+
+	out_be32(cfg, in_be32(cfg) & ~0x30000000u);
+}
+
+static void spider_ack_irq(struct irq_data *d)
+{
+	struct spider_pic *pic = spider_irq_data_to_pic(d);
+	unsigned int src = irqd_to_hwirq(d);
+
+	/* Reset edge detection logic if necessary
+	 */
+	if (irqd_is_level_type(d))
+		return;
+
+	/* Only interrupts 47 to 50 can be set to edge */
+	if (src < 47 || src > 50)
+		return;
+
+	/* Perform the clear of the edge logic */
+	out_be32(pic->regs + TIR_EDC, 0x100 | (src & 0xf));
+}
+
+static int spider_set_irq_type(struct irq_data *d, unsigned int type)
+{
+	unsigned int sense = type & IRQ_TYPE_SENSE_MASK;
+	struct spider_pic *pic = spider_irq_data_to_pic(d);
+	unsigned int hw = irqd_to_hwirq(d);
+	void __iomem *cfg = spider_get_irq_config(pic, hw);
+	u32 old_mask;
+	u32 ic;
+
+	/* Note that only level high is supported for most interrupts */
+	if (sense != IRQ_TYPE_NONE && sense != IRQ_TYPE_LEVEL_HIGH &&
+	    (hw < 47 || hw > 50))
+		return -EINVAL;
+
+	/* Decode sense type */
+	switch(sense) {
+	case IRQ_TYPE_EDGE_RISING:
+		ic = 0x3;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		ic = 0x2;
+		break;
+	case IRQ_TYPE_LEVEL_LOW:
+		ic = 0x0;
+		break;
+	case IRQ_TYPE_LEVEL_HIGH:
+	case IRQ_TYPE_NONE:
+		ic = 0x1;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	/* Configure the source. One gross hack that was there before and
+	 * that I've kept around is the priority to the BE which I set to
+	 * be the same as the interrupt source number. I don't know whether
+	 * that's supposed to make any kind of sense however, we'll have to
+	 * decide that, but for now, I'm not changing the behaviour.
+	 */
+	old_mask = in_be32(cfg) & 0x30000000u;
+	out_be32(cfg, old_mask | (ic << 24) | (0x7 << 16) |
+		 (pic->node_id << 4) | 0xe);
+	out_be32(cfg + 4, (0x2 << 16) | (hw & 0xff));
+
+	return 0;
+}
+
+static struct irq_chip spider_pic = {
+	.name = "SPIDER",
+	.irq_unmask = spider_unmask_irq,
+	.irq_mask = spider_mask_irq,
+	.irq_ack = spider_ack_irq,
+	.irq_set_type = spider_set_irq_type,
+};
+
+static int spider_host_map(struct irq_domain *h, unsigned int virq,
+			irq_hw_number_t hw)
+{
+	irq_set_chip_data(virq, h->host_data);
+	irq_set_chip_and_handler(virq, &spider_pic, handle_level_irq);
+
+	/* Set default irq type */
+	irq_set_irq_type(virq, IRQ_TYPE_NONE);
+
+	return 0;
+}
+
+static int spider_host_xlate(struct irq_domain *h, struct device_node *ct,
+			   const u32 *intspec, unsigned int intsize,
+			   irq_hw_number_t *out_hwirq, unsigned int *out_flags)
+
+{
+	/* Spider interrupts have 2 cells, first is the interrupt source,
+	 * second, well, I don't know for sure yet ... We mask the top bits
+	 * because old device-trees encode a node number in there
+	 */
+	*out_hwirq = intspec[0] & 0x3f;
+	*out_flags = IRQ_TYPE_LEVEL_HIGH;
+	return 0;
+}
+
+static const struct irq_domain_ops spider_host_ops = {
+	.map = spider_host_map,
+	.xlate = spider_host_xlate,
+};
+
+static void spider_irq_cascade(struct irq_desc *desc)
+{
+	struct irq_chip *chip = irq_desc_get_chip(desc);
+	struct spider_pic *pic = irq_desc_get_handler_data(desc);
+	unsigned int cs;
+
+	cs = in_be32(pic->regs + TIR_CS) >> 24;
+	if (cs != SPIDER_IRQ_INVALID)
+		generic_handle_domain_irq(pic->host, cs);
+
+	chip->irq_eoi(&desc->irq_data);
+}
+
+/* For hooking up the cascade we have a problem. Our device-tree is
+ * crap and we don't know on which BE iic interrupt we are hooked on at
+ * least not the "standard" way. We can reconstitute it based on two
+ * informations though: which BE node we are connected to and whether
+ * we are connected to IOIF0 or IOIF1. Right now, we really only care
+ * about the IBM cell blade and we know that its firmware gives us an
+ * interrupt-map property which is pretty strange.
+ */
+static unsigned int __init spider_find_cascade_and_node(struct spider_pic *pic)
+{
+	unsigned int virq;
+	const u32 *imap, *tmp;
+	int imaplen, intsize, unit;
+	struct device_node *iic;
+	struct device_node *of_node;
+
+	of_node = irq_domain_get_of_node(pic->host);
+
+	/* First, we check whether we have a real "interrupts" in the device
+	 * tree in case the device-tree is ever fixed
+	 */
+	virq = irq_of_parse_and_map(of_node, 0);
+	if (virq)
+		return virq;
+
+	/* Now do the horrible hacks */
+	tmp = of_get_property(of_node, "#interrupt-cells", NULL);
+	if (tmp == NULL)
+		return 0;
+	intsize = *tmp;
+	imap = of_get_property(of_node, "interrupt-map", &imaplen);
+	if (imap == NULL || imaplen < (intsize + 1))
+		return 0;
+	iic = of_find_node_by_phandle(imap[intsize]);
+	if (iic == NULL)
+		return 0;
+	imap += intsize + 1;
+	tmp = of_get_property(iic, "#interrupt-cells", NULL);
+	if (tmp == NULL) {
+		of_node_put(iic);
+		return 0;
+	}
+	intsize = *tmp;
+	/* Assume unit is last entry of interrupt specifier */
+	unit = imap[intsize - 1];
+	/* Ok, we have a unit, now let's try to get the node */
+	tmp = of_get_property(iic, "ibm,interrupt-server-ranges", NULL);
+	if (tmp == NULL) {
+		of_node_put(iic);
+		return 0;
+	}
+	/* ugly as hell but works for now */
+	pic->node_id = (*tmp) >> 1;
+	of_node_put(iic);
+
+	/* Ok, now let's get cracking. You may ask me why I just didn't match
+	 * the iic host from the iic OF node, but that way I'm still compatible
+	 * with really really old old firmwares for which we don't have a node
+	 */
+	/* Manufacture an IIC interrupt number of class 2 */
+	virq = irq_create_mapping(NULL,
+				  (pic->node_id << IIC_IRQ_NODE_SHIFT) |
+				  (2 << IIC_IRQ_CLASS_SHIFT) |
+				  unit);
+	if (!virq)
+		printk(KERN_ERR "spider_pic: failed to map cascade !");
+	return virq;
+}
+
+
+static void __init spider_init_one(struct device_node *of_node, int chip,
+				   unsigned long addr)
+{
+	struct spider_pic *pic = &spider_pics[chip];
+	int i, virq;
+
+	/* Map registers */
+	pic->regs = ioremap(addr, 0x1000);
+	if (pic->regs == NULL)
+		panic("spider_pic: can't map registers !");
+
+	/* Allocate a host */
+	pic->host = irq_domain_add_linear(of_node, SPIDER_SRC_COUNT,
+					  &spider_host_ops, pic);
+	if (pic->host == NULL)
+		panic("spider_pic: can't allocate irq host !");
+
+	/* Go through all sources and disable them */
+	for (i = 0; i < SPIDER_SRC_COUNT; i++) {
+		void __iomem *cfg = pic->regs + TIR_CFGA + 8 * i;
+		out_be32(cfg, in_be32(cfg) & ~0x30000000u);
+	}
+
+	/* do not mask any interrupts because of level */
+	out_be32(pic->regs + TIR_MSK, 0x0);
+
+	/* enable interrupt packets to be output */
+	out_be32(pic->regs + TIR_PIEN, in_be32(pic->regs + TIR_PIEN) | 0x1);
+
+	/* Hook up the cascade interrupt to the iic and nodeid */
+	virq = spider_find_cascade_and_node(pic);
+	if (!virq)
+		return;
+	irq_set_handler_data(virq, pic);
+	irq_set_chained_handler(virq, spider_irq_cascade);
+
+	printk(KERN_INFO "spider_pic: node %d, addr: 0x%lx %pOF\n",
+	       pic->node_id, addr, of_node);
+
+	/* Enable the interrupt detection enable bit. Do this last! */
+	out_be32(pic->regs + TIR_DEN, in_be32(pic->regs + TIR_DEN) | 0x1);
+}
+
+void __init spider_init_IRQ(void)
+{
+	struct resource r;
+	struct device_node *dn;
+	int chip = 0;
+
+	/* XXX node numbers are totally bogus. We _hope_ we get the device
+	 * nodes in the right order here but that's definitely not guaranteed,
+	 * we need to get the node from the device tree instead.
+	 * There is currently no proper property for it (but our whole
+	 * device-tree is bogus anyway) so all we can do is pray or maybe test
+	 * the address and deduce the node-id
+	 */
+	for_each_node_by_name(dn, "interrupt-controller") {
+		if (of_device_is_compatible(dn, "CBEA,platform-spider-pic")) {
+			if (of_address_to_resource(dn, 0, &r)) {
+				printk(KERN_WARNING "spider-pic: Failed\n");
+				continue;
+			}
+		} else if (of_device_is_compatible(dn, "sti,platform-spider-pic")
+			   && (chip < 2)) {
+			static long hard_coded_pics[] =
+				{ 0x24000008000ul, 0x34000008000ul};
+			r.start = hard_coded_pics[chip];
+		} else
+			continue;
+		spider_init_one(dn, chip++, r.start);
+	}
+}