/*
* Cell Internal Interrupt Controller
*
* Copyright (C) 2006 Benjamin Herrenschmidt (benh@kernel.crashing.org)
* IBM, Corp.
*
* (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 <linux/module.h>
#include <linux/percpu.h>
#include <linux/types.h>
#include <linux/ioport.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/ptrace.h>
#include <asm/machdep.h>
#include "interrupt.h"
#include "cbe_regs.h"
struct iic {
struct cbe_iic_thread_regs __iomem *regs;
u8 target_id;
u8 eoi_stack[16];
int eoi_ptr;
struct irq_host *host;
};
static DEFINE_PER_CPU(struct iic, iic);
#define IIC_NODE_COUNT 2
static struct irq_host *iic_hosts[IIC_NODE_COUNT];
/* Convert between "pending" bits and hw irq number */
static irq_hw_number_t iic_pending_to_hwnum(struct cbe_iic_pending_bits bits)
{
unsigned char unit = bits.source & 0xf;
if (bits.flags & CBE_IIC_IRQ_IPI)
return IIC_IRQ_IPI0 | (bits.prio >> 4);
else if (bits.class <= 3)
return (bits.class << 4) | unit;
else
return IIC_IRQ_INVALID;
}
static void iic_mask(unsigned int irq)
{
}
static void iic_unmask(unsigned int irq)
{
}
static void iic_eoi(unsigned int irq)
{
struct iic *iic = &__get_cpu_var(iic);
out_be64(&iic->regs->prio, iic->eoi_stack[--iic->eoi_ptr]);
BUG_ON(iic->eoi_ptr < 0);
}
static struct irq_chip iic_chip = {
.typename = " CELL-IIC ",
.mask = iic_mask,
.unmask = iic_unmask,
.eoi = iic_eoi,
};
/* Get an IRQ number from the pending state register of the IIC */
static unsigned int iic_get_irq(struct pt_regs *regs)
{
struct cbe_iic_pending_bits pending;
struct iic *iic;
iic = &__get_cpu_var(iic);
*(unsigned long *) &pending =
in_be64((unsigned long __iomem *) &iic->regs->pending_destr);
iic->eoi_stack[++iic->eoi_ptr] = pending.prio;
BUG_ON(iic->eoi_ptr > 15);
if (pending.flags & CBE_IIC_IRQ_VALID)
return irq_linear_revmap(iic->host,
iic_pending_to_hwnum(pending));
return NO_IRQ;
}
#ifdef CONFIG_SMP
/* Use the highest interrupt priorities for IPI */
static inline int iic_ipi_to_irq(int ipi)
{
return IIC_IRQ_IPI0 + IIC_NUM_IPIS - 1 - ipi;
}
static inline int iic_irq_to_ipi(int irq)
{
return IIC_NUM_IPIS - 1 - (irq - IIC_IRQ_IPI0);
}
void iic_setup_cpu(void)
{
out_be64(&__get_cpu_var(iic).regs->prio, 0xff);
}
void iic_cause_IPI(int cpu, int mesg)
{
out_be64(&per_cpu(iic, cpu).regs->generate, (IIC_NUM_IPIS - 1 - mesg) << 4);
}
u8 iic_get_target_id(int cpu)
{
return per_cpu(iic, cpu).target_id;
}
EXPORT_SYMBOL_GPL(iic_get_target_id);
struct irq_host *iic_get_irq_host(int node)
{
if (node < 0 || node >= IIC_NODE_COUNT)
return NULL;
return iic_hosts[node];
}
EXPORT_SYMBOL_GPL(iic_get_irq_host);
static irqreturn_t iic_ipi_action(int irq, void *dev_id, struct pt_regs *regs)
{
int ipi = (int)(long)dev_id;
smp_message_recv(ipi, regs);
return IRQ_HANDLED;
}
static void iic_request_ipi(int ipi, const char *name)
{
int node, virq;
for (node = 0; node < IIC_NODE_COUNT; node++) {
char *rname;
if (iic_hosts[node] == NULL)
continue;
virq = irq_create_mapping(iic_hosts[node],
iic_ipi_to_irq(ipi));
if (virq == NO_IRQ) {
printk(KERN_ERR
"iic: failed to map IPI %s on node %d\n",
name, node);
continue;
}
rname = kzalloc(strlen(name) + 16, GFP_KERNEL);
if (rname)
sprintf(rname, "%s node %d", name, node);
else
rname = (char *)name;
if (request_irq(virq, iic_ipi_action, IRQF_DISABLED,
rname, (void *)(long)ipi))
printk(KERN_ERR
"iic: failed to request IPI %s on node %d\n",
name, node);
}
}
void iic_request_IPIs(void)
{
iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
#ifdef CONFIG_DEBUGGER
iic_request_ipi(PPC_MSG_DEBUGGER_BREAK, "IPI-debug");
#endif /* CONFIG_DEBUGGER */
}
#endif /* CONFIG_SMP */
static int iic_host_match(struct irq_host *h, struct device_node *node)
{
return h->host_data != NULL && node == h->host_data;
}
static int iic_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
if (hw < IIC_IRQ_IPI0)
set_irq_chip_and_handler(virq, &iic_chip, handle_fasteoi_irq);
else
set_irq_chip_and_handler(virq, &iic_chip, handle_percpu_irq);
return 0;
}
static int iic_host_xlate(struct irq_host *h, struct device_node *ct,
u32 *intspec, unsigned int intsize,
irq_hw_number_t *out_hwirq, unsigned int *out_flags)
{
/* Currently, we don't translate anything. That needs to be fixed as
* we get better defined device-trees. iic interrupts have to be
* explicitely mapped by whoever needs them
*/
return -ENODEV;
}
static struct irq_host_ops iic_host_ops = {
.match = iic_host_match,
.map = iic_host_map,
.xlate = iic_host_xlate,
};
static void __init init_one_iic(unsigned int hw_cpu, unsigned long addr,
struct irq_host *host)
{
/* XXX FIXME: should locate the linux CPU number from the HW cpu
* number properly. We are lucky for now
*/
struct iic *iic = &per_cpu(iic, hw_cpu);
iic->regs = ioremap(addr, sizeof(struct cbe_iic_thread_regs));
BUG_ON(iic->regs == NULL);
iic->target_id = ((hw_cpu & 2) << 3) | ((hw_cpu & 1) ? 0xf : 0xe);
iic->eoi_stack[0] = 0xff;
iic->host = host;
out_be64(&iic->regs->prio, 0);
printk(KERN_INFO "IIC for CPU %d at %lx mapped to %p, target id 0x%x\n",
hw_cpu, addr, iic->regs, iic->target_id);
}
static int __init setup_iic(void)
{
struct device_node *dn;
struct resource r0, r1;
struct irq_host *host;
int found = 0;
const u32 *np;
for (dn = NULL;
(dn = of_find_node_by_name(dn,"interrupt-controller")) != NULL;) {
if (!device_is_compatible(dn,
"IBM,CBEA-Internal-Interrupt-Controller"))
continue;
np = get_property(dn, "ibm,interrupt-server-ranges", NULL);
if (np == NULL) {
printk(KERN_WARNING "IIC: CPU association not found\n");
of_node_put(dn);
return -ENODEV;
}
if (of_address_to_resource(dn, 0, &r0) ||
of_address_to_resource(dn, 1, &r1)) {
printk(KERN_WARNING "IIC: Can't resolve addresses\n");
of_node_put(dn);
return -ENODEV;
}
host = NULL;
if (found < IIC_NODE_COUNT) {
host = irq_alloc_host(IRQ_HOST_MAP_LINEAR,
IIC_SOURCE_COUNT,
&iic_host_ops,
IIC_IRQ_INVALID);
iic_hosts[found] = host;
BUG_ON(iic_hosts[found] == NULL);
iic_hosts[found]->host_data = of_node_get(dn);
found++;
}
init_one_iic(np[0], r0.start, host);
init_one_iic(np[1], r1.start, host);
}
if (found)
return 0;
else
return -ENODEV;
}
void __init iic_init_IRQ(void)
{
/* Discover and initialize iics */
if (setup_iic() < 0)
panic("IIC: Failed to initialize !\n");
/* Set master interrupt handling function */
ppc_md.get_irq = iic_get_irq;
/* Enable on current CPU */
iic_setup_cpu();
}
