// 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);
}
}