/*
* 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.
*
* TODO:
* - Fix various assumptions related to HW CPU numbers vs. linux CPU numbers
* vs node numbers in the setup code
* - Implement proper handling of maxcpus=1/2 (that is, routing of irqs from
* a non-active node to the active node)
*/
#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 <linux/kernel_stat.h>
#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/ptrace.h>
#include <asm/machdep.h>
#include <asm/cell-regs.h>
#include "interrupt.h"
struct iic {
struct cbe_iic_thread_regs __iomem *regs;
u8 target_id;
u8 eoi_stack[16];
int eoi_ptr;
struct device_node *node;
};
static DEFINE_PER_CPU(struct iic, cpu_iic);
#define IIC_NODE_COUNT 2
static struct irq_host *iic_host;
/* 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;
unsigned char node = bits.source >> 4;
unsigned char class = bits.class & 3;
/* Decode IPIs */
if (bits.flags & CBE_IIC_IRQ_IPI)
return IIC_IRQ_TYPE_IPI | (bits.prio >> 4);
else
return (node << IIC_IRQ_NODE_SHIFT) | (class << 4) | unit;
}
static void iic_mask(struct irq_data *d)
{
}
static void iic_unmask(struct irq_data *d)
{
}
static void iic_eoi(struct irq_data *d)
{
struct iic *iic = &__get_cpu_var(cpu_iic);
out_be64(&iic->regs->prio, iic->eoi_stack[--iic->eoi_ptr]);
BUG_ON(iic->eoi_ptr < 0);
}
static struct irq_chip iic_chip = {
.name = "CELL-IIC",
.irq_mask = iic_mask,
.irq_unmask = iic_unmask,
.irq_eoi = iic_eoi,
};
static void iic_ioexc_eoi(struct irq_data *d)
{
}
static void iic_ioexc_cascade(unsigned int irq, struct irq_desc *desc)
{
struct irq_chip *chip = irq_desc_get_chip(desc);
struct cbe_iic_regs __iomem *node_iic =
(void __iomem *)irq_desc_get_handler_data(desc);
unsigned int base = (irq & 0xffffff00) | IIC_IRQ_TYPE_IOEXC;
unsigned long bits, ack;
int cascade;
for (;;) {
bits = in_be64(&node_iic->iic_is);
if (bits == 0)
break;
/* pre-ack edge interrupts */
ack = bits & IIC_ISR_EDGE_MASK;
if (ack)
out_be64(&node_iic->iic_is, ack);
/* handle them */
for (cascade = 63; cascade >= 0; cascade--)
if (bits & (0x8000000000000000UL >> cascade)) {
unsigned int cirq =
irq_linear_revmap(iic_host,
base | cascade);
if (cirq != NO_IRQ)
generic_handle_irq(cirq);
}
/* post-ack level interrupts */
ack = bits & ~IIC_ISR_EDGE_MASK;
if (ack)
out_be64(&node_iic->iic_is, ack);
}
chip->irq_eoi(&desc->irq_data);
}
static struct irq_chip iic_ioexc_chip = {
.name = "CELL-IOEX",
.irq_mask = iic_mask,
.irq_unmask = iic_unmask,
.irq_eoi = iic_ioexc_eoi,
};
/* Get an IRQ number from the pending state register of the IIC */
static unsigned int iic_get_irq(void)
{
struct cbe_iic_pending_bits pending;
struct iic *iic;
unsigned int virq;
iic = &__get_cpu_var(cpu_iic);
*(unsigned long *) &pending =
in_be64((u64 __iomem *) &iic->regs->pending_destr);
if (!(pending.flags & CBE_IIC_IRQ_VALID))
return NO_IRQ;
virq = irq_linear_revmap(iic_host, iic_pending_to_hwnum(pending));
if (virq == NO_IRQ)
return NO_IRQ;
iic->eoi_stack[++iic->eoi_ptr] = pending.prio;
BUG_ON(iic->eoi_ptr > 15);
return virq;
}
void iic_setup_cpu(void)
{
out_be64(&__get_cpu_var(cpu_iic).regs->prio, 0xff);
}
u8 iic_get_target_id(int cpu)
{
return per_cpu(cpu_iic, cpu).target_id;
}
EXPORT_SYMBOL_GPL(iic_get_target_id);
#ifdef CONFIG_SMP
/* Use the highest interrupt priorities for IPI */
static inline int iic_ipi_to_irq(int ipi)
{
return IIC_IRQ_TYPE_IPI + 0xf - ipi;
}
void iic_cause_IPI(int cpu, int mesg)
{
out_be64(&per_cpu(cpu_iic, cpu).regs->generate, (0xf - mesg) << 4);
}
struct irq_host *iic_get_irq_host(int node)
{
return iic_host;
}
EXPORT_SYMBOL_GPL(iic_get_irq_host);
static irqreturn_t iic_ipi_action(int irq, void *dev_id)
{
int ipi = (int)(long)dev_id;
smp_message_recv(ipi);
return IRQ_HANDLED;
}
static void iic_request_ipi(int ipi, const char *name)
{
int virq;
virq = irq_create_mapping(iic_host, iic_ipi_to_irq(ipi));
if (virq == NO_IRQ) {
printk(KERN_ERR
"iic: failed to map IPI %s\n", name);
return;
}
if (request_irq(virq, iic_ipi_action, IRQF_DISABLED, name,
(void *)(long)ipi))
printk(KERN_ERR
"iic: failed to request IPI %s\n", name);
}
void iic_request_IPIs(void)
{
iic_request_ipi(PPC_MSG_CALL_FUNCTION, "IPI-call");
iic_request_ipi(PPC_MSG_RESCHEDULE, "IPI-resched");
iic_request_ipi(PPC_MSG_CALL_FUNC_SINGLE, "IPI-call-single");
#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 of_device_is_compatible(node,
"IBM,CBEA-Internal-Interrupt-Controller");
}
static int iic_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
switch (hw & IIC_IRQ_TYPE_MASK) {
case IIC_IRQ_TYPE_IPI:
irq_set_chip_and_handler(virq, &iic_chip, handle_percpu_irq);
break;
case IIC_IRQ_TYPE_IOEXC:
irq_set_chip_and_handler(virq, &iic_ioexc_chip,
handle_edge_eoi_irq);
break;
default:
irq_set_chip_and_handler(virq, &iic_chip, handle_edge_eoi_irq);
}
return 0;
}
static int iic_host_xlate(struct irq_host *h, struct device_node *ct,
const u32 *intspec, unsigned int intsize,
irq_hw_number_t *out_hwirq, unsigned int *out_flags)
{
unsigned int node, ext, unit, class;
const u32 *val;
if (!of_device_is_compatible(ct,
"IBM,CBEA-Internal-Interrupt-Controller"))
return -ENODEV;
if (intsize != 1)
return -ENODEV;
val = of_get_property(ct, "#interrupt-cells", NULL);
if (val == NULL || *val != 1)
return -ENODEV;
node = intspec[0] >> 24;
ext = (intspec[0] >> 16) & 0xff;
class = (intspec[0] >> 8) & 0xff;
unit = intspec[0] & 0xff;
/* Check if node is in supported range */
if (node > 1)
return -EINVAL;
/* Build up interrupt number, special case for IO exceptions */
*out_hwirq = (node << IIC_IRQ_NODE_SHIFT);
if (unit == IIC_UNIT_IIC && class == 1)
*out_hwirq |= IIC_IRQ_TYPE_IOEXC | ext;
else
*out_hwirq |= IIC_IRQ_TYPE_NORMAL |
(class << IIC_IRQ_CLASS_SHIFT) | unit;
/* Dummy flags, ignored by iic code */
*out_flags = IRQ_TYPE_EDGE_RISING;
return 0;
}
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 device_node *node)
{
/* XXX FIXME: should locate the linux CPU number from the HW cpu
* number properly. We are lucky for now
*/
struct iic *iic = &per_cpu(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->node = of_node_get(node);
out_be64(&iic->regs->prio, 0);
printk(KERN_INFO "IIC for CPU %d target id 0x%x : %s\n",
hw_cpu, iic->target_id, node->full_name);
}
static int __init setup_iic(void)
{
struct device_node *dn;
struct resource r0, r1;
unsigned int node, cascade, found = 0;
struct cbe_iic_regs __iomem *node_iic;
const u32 *np;
for (dn = NULL;
(dn = of_find_node_by_name(dn,"interrupt-controller")) != NULL;) {
if (!of_device_is_compatible(dn,
"IBM,CBEA-Internal-Interrupt-Controller"))
continue;
np = of_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;
}
found++;
init_one_iic(np[0], r0.start, dn);
init_one_iic(np[1], r1.start, dn);
/* Setup cascade for IO exceptions. XXX cleanup tricks to get
* node vs CPU etc...
* Note that we configure the IIC_IRR here with a hard coded
* priority of 1. We might want to improve that later.
*/
node = np[0] >> 1;
node_iic = cbe_get_cpu_iic_regs(np[0]);
cascade = node << IIC_IRQ_NODE_SHIFT;
cascade |= 1 << IIC_IRQ_CLASS_SHIFT;
cascade |= IIC_UNIT_IIC;
cascade = irq_create_mapping(iic_host, cascade);
if (cascade == NO_IRQ)
continue;
/*
* irq_data is a generic pointer that gets passed back
* to us later, so the forced cast is fine.
*/
irq_set_handler_data(cascade, (void __force *)node_iic);
irq_set_chained_handler(cascade, iic_ioexc_cascade);
out_be64(&node_iic->iic_ir,
(1 << 12) /* priority */ |
(node << 4) /* dest node */ |
IIC_UNIT_THREAD_0 /* route them to thread 0 */);
/* Flush pending (make sure it triggers if there is
* anything pending
*/
out_be64(&node_iic->iic_is, 0xfffffffffffffffful);
}
if (found)
return 0;
else
return -ENODEV;
}
void __init iic_init_IRQ(void)
{
/* Setup an irq host data structure */
iic_host = irq_alloc_host(NULL, IRQ_HOST_MAP_LINEAR, IIC_SOURCE_COUNT,
&iic_host_ops, IIC_IRQ_INVALID);
BUG_ON(iic_host == NULL);
irq_set_default_host(iic_host);
/* 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();
}
void iic_set_interrupt_routing(int cpu, int thread, int priority)
{
struct cbe_iic_regs __iomem *iic_regs = cbe_get_cpu_iic_regs(cpu);
u64 iic_ir = 0;
int node = cpu >> 1;
/* Set which node and thread will handle the next interrupt */
iic_ir |= CBE_IIC_IR_PRIO(priority) |
CBE_IIC_IR_DEST_NODE(node);
if (thread == 0)
iic_ir |= CBE_IIC_IR_DEST_UNIT(CBE_IIC_IR_PT_0);
else
iic_ir |= CBE_IIC_IR_DEST_UNIT(CBE_IIC_IR_PT_1);
out_be64(&iic_regs->iic_ir, iic_ir);
}
