/*
* External Interrupt Controller on Spider South Bridge
*
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
*
* Author: Arnd Bergmann <arndb@de.ibm.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, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <asm/pgtable.h>
#include <asm/prom.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*/
};
static void __iomem *spider_pics[4];
static void __iomem *spider_get_pic(int irq)
{
int node = irq / IIC_NODE_STRIDE;
irq %= IIC_NODE_STRIDE;
if (irq >= IIC_EXT_OFFSET &&
irq < IIC_EXT_OFFSET + IIC_NUM_EXT &&
spider_pics)
return spider_pics[node];
return NULL;
}
static int spider_get_nr(unsigned int irq)
{
return (irq % IIC_NODE_STRIDE) - IIC_EXT_OFFSET;
}
static void __iomem *spider_get_irq_config(int irq)
{
void __iomem *pic;
pic = spider_get_pic(irq);
return pic + TIR_CFGA + 8 * spider_get_nr(irq);
}
static void spider_unmask_irq(unsigned int irq)
{
int nodeid = (irq / IIC_NODE_STRIDE) * 0x10;
void __iomem *cfg = spider_get_irq_config(irq);
irq = spider_get_nr(irq);
/* FIXME: Most of that is configuration and has nothing to do with enabling/disable,
* besides, it's also partially bogus.
*/
out_be32(cfg, (in_be32(cfg) & ~0xf0)| 0x3107000eu | nodeid);
out_be32(cfg + 4, in_be32(cfg + 4) | 0x00020000u | irq);
}
static void spider_mask_irq(unsigned int irq)
{
void __iomem *cfg = spider_get_irq_config(irq);
irq = spider_get_nr(irq);
out_be32(cfg, in_be32(cfg) & ~0x30000000u);
}
static void spider_ack_irq(unsigned int irq)
{
/* Should reset edge detection logic but we don't configure any edge interrupt
* at the moment.
*/
}
static struct irq_chip spider_pic = {
.typename = " SPIDER ",
.unmask = spider_unmask_irq,
.mask = spider_mask_irq,
.ack = spider_ack_irq,
};
static int spider_get_irq(int node)
{
unsigned long cs;
void __iomem *regs = spider_pics[node];
cs = in_be32(regs + TIR_CS) >> 24;
if (cs == 63)
return -1;
else
return cs;
}
static void spider_irq_cascade(unsigned int irq, struct irq_desc *desc,
struct pt_regs *regs)
{
int node = (int)(long)desc->handler_data;
int cascade_irq;
cascade_irq = spider_get_irq(node);
generic_handle_irq(cascade_irq, regs);
desc->chip->eoi(irq);
}
/* hardcoded part to be compatible with older firmware */
static void __init spider_init_one(int node, unsigned long addr)
{
int n, irq;
spider_pics[node] = ioremap(addr, 0x800);
if (spider_pics[node] == NULL)
panic("spider_pic: can't map registers !");
printk(KERN_INFO "spider_pic: mapped for node %d, addr: 0x%lx mapped to %p\n",
node, addr, spider_pics[node]);
for (n = 0; n < IIC_NUM_EXT; n++) {
if (n == IIC_EXT_CASCADE)
continue;
irq = n + IIC_EXT_OFFSET + node * IIC_NODE_STRIDE;
set_irq_chip_and_handler(irq, &spider_pic, handle_level_irq);
get_irq_desc(irq)->status |= IRQ_LEVEL;
}
/* do not mask any interrupts because of level */
out_be32(spider_pics[node] + TIR_MSK, 0x0);
/* disable edge detection clear */
/* out_be32(spider_pics[node] + TIR_EDC, 0x0); */
/* enable interrupt packets to be output */
out_be32(spider_pics[node] + TIR_PIEN,
in_be32(spider_pics[node] + TIR_PIEN) | 0x1);
/* Hook up cascade */
irq = IIC_EXT_CASCADE + node * IIC_NODE_STRIDE;
set_irq_data(irq, (void *)(long)node);
set_irq_chained_handler(irq, spider_irq_cascade);
/* Enable the interrupt detection enable bit. Do this last! */
out_be32(spider_pics[node] + TIR_DEN,
in_be32(spider_pics[node] + TIR_DEN) | 0x1);
}
void __init spider_init_IRQ(void)
{
unsigned long *spider_reg;
struct device_node *dn;
char *compatible;
int node = 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 (dn = NULL; (dn = of_find_node_by_name(dn, "interrupt-controller"));) {
compatible = (char *)get_property(dn, "compatible", NULL);
if (!compatible)
continue;
if (strstr(compatible, "CBEA,platform-spider-pic"))
spider_reg = (unsigned long *)get_property(dn, "reg", NULL);
else if (strstr(compatible, "sti,platform-spider-pic") && (node < 2)) {
static long hard_coded_pics[] = { 0x24000008000, 0x34000008000 };
spider_reg = &hard_coded_pics[node];
} else
continue;
if (spider_reg == NULL)
printk(KERN_ERR "spider_pic: No address for node %d\n", node);
spider_init_one(node, *spider_reg);
node++;
}
}
