/*
* This module supports the iSeries PCI bus interrupt handling
* Copyright (C) 20yy <Robert L Holtorf> <IBM Corp>
* Copyright (C) 2004-2005 IBM Corporation
*
* 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 of the License, 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.,
* 59 Temple Place, Suite 330,
* Boston, MA 02111-1307 USA
*
* Change Activity:
* Created, December 13, 2000 by Wayne Holm
* End Change Activity
*/
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/threads.h>
#include <linux/smp.h>
#include <linux/param.h>
#include <linux/string.h>
#include <linux/bootmem.h>
#include <linux/irq.h>
#include <linux/spinlock.h>
#include <asm/paca.h>
#include <asm/iseries/hv_types.h>
#include <asm/iseries/hv_lp_event.h>
#include <asm/iseries/hv_call_xm.h>
#include <asm/iseries/it_lp_queue.h>
#include "irq.h"
#include "pci.h"
#include "call_pci.h"
#include "smp.h"
#ifdef CONFIG_PCI
enum pci_event_type {
pe_bus_created = 0, /* PHB has been created */
pe_bus_error = 1, /* PHB has failed */
pe_bus_failed = 2, /* Msg to Secondary, Primary failed bus */
pe_node_failed = 4, /* Multi-adapter bridge has failed */
pe_node_recovered = 5, /* Multi-adapter bridge has recovered */
pe_bus_recovered = 12, /* PHB has been recovered */
pe_unquiese_bus = 18, /* Secondary bus unqiescing */
pe_bridge_error = 21, /* Bridge Error */
pe_slot_interrupt = 22 /* Slot interrupt */
};
struct pci_event {
struct HvLpEvent event;
union {
u64 __align; /* Align on an 8-byte boundary */
struct {
u32 fisr;
HvBusNumber bus_number;
HvSubBusNumber sub_bus_number;
HvAgentId dev_id;
} slot;
struct {
HvBusNumber bus_number;
HvSubBusNumber sub_bus_number;
} bus;
struct {
HvBusNumber bus_number;
HvSubBusNumber sub_bus_number;
HvAgentId dev_id;
} node;
} data;
};
static DEFINE_SPINLOCK(pending_irqs_lock);
static int num_pending_irqs;
static int pending_irqs[NR_IRQS];
static void int_received(struct pci_event *event)
{
int irq;
switch (event->event.xSubtype) {
case pe_slot_interrupt:
irq = event->event.xCorrelationToken;
if (irq < NR_IRQS) {
spin_lock(&pending_irqs_lock);
pending_irqs[irq]++;
num_pending_irqs++;
spin_unlock(&pending_irqs_lock);
} else {
printk(KERN_WARNING "int_received: bad irq number %d\n",
irq);
HvCallPci_eoi(event->data.slot.bus_number,
event->data.slot.sub_bus_number,
event->data.slot.dev_id);
}
break;
/* Ignore error recovery events for now */
case pe_bus_created:
printk(KERN_INFO "int_received: system bus %d created\n",
event->data.bus.bus_number);
break;
case pe_bus_error:
case pe_bus_failed:
printk(KERN_INFO "int_received: system bus %d failed\n",
event->data.bus.bus_number);
break;
case pe_bus_recovered:
case pe_unquiese_bus:
printk(KERN_INFO "int_received: system bus %d recovered\n",
event->data.bus.bus_number);
break;
case pe_node_failed:
case pe_bridge_error:
printk(KERN_INFO
"int_received: multi-adapter bridge %d/%d/%d failed\n",
event->data.node.bus_number,
event->data.node.sub_bus_number,
event->data.node.dev_id);
break;
case pe_node_recovered:
printk(KERN_INFO
"int_received: multi-adapter bridge %d/%d/%d recovered\n",
event->data.node.bus_number,
event->data.node.sub_bus_number,
event->data.node.dev_id);
break;
default:
printk(KERN_ERR
"int_received: unrecognized event subtype 0x%x\n",
event->event.xSubtype);
break;
}
}
static void pci_event_handler(struct HvLpEvent *event)
{
if (event && (event->xType == HvLpEvent_Type_PciIo)) {
if (hvlpevent_is_int(event))
int_received((struct pci_event *)event);
else
printk(KERN_ERR
"pci_event_handler: unexpected ack received\n");
} else if (event)
printk(KERN_ERR
"pci_event_handler: Unrecognized PCI event type 0x%x\n",
(int)event->xType);
else
printk(KERN_ERR "pci_event_handler: NULL event received\n");
}
#define REAL_IRQ_TO_SUBBUS(irq) (((irq) >> 14) & 0xff)
#define REAL_IRQ_TO_BUS(irq) ((((irq) >> 6) & 0xff) + 1)
#define REAL_IRQ_TO_IDSEL(irq) ((((irq) >> 3) & 7) + 1)
#define REAL_IRQ_TO_FUNC(irq) ((irq) & 7)
/*
* This will be called by device drivers (via enable_IRQ)
* to enable INTA in the bridge interrupt status register.
*/
static void iseries_enable_IRQ(unsigned int irq)
{
u32 bus, dev_id, function, mask;
const u32 sub_bus = 0;
unsigned int rirq = (unsigned int)irq_map[irq].hwirq;
/* The IRQ has already been locked by the caller */
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Unmask secondary INTA */
mask = 0x80000000;
HvCallPci_unmaskInterrupts(bus, sub_bus, dev_id, mask);
}
/* This is called by iseries_activate_IRQs */
static unsigned int iseries_startup_IRQ(unsigned int irq)
{
u32 bus, dev_id, function, mask;
const u32 sub_bus = 0;
unsigned int rirq = (unsigned int)irq_map[irq].hwirq;
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Link the IRQ number to the bridge */
HvCallXm_connectBusUnit(bus, sub_bus, dev_id, irq);
/* Unmask bridge interrupts in the FISR */
mask = 0x01010000 << function;
HvCallPci_unmaskFisr(bus, sub_bus, dev_id, mask);
iseries_enable_IRQ(irq);
return 0;
}
/*
* This is called out of iSeries_fixup to activate interrupt
* generation for usable slots
*/
void __init iSeries_activate_IRQs()
{
int irq;
unsigned long flags;
for_each_irq (irq) {
struct irq_desc *desc = irq_to_desc(irq);
if (desc && desc->chip && desc->chip->startup) {
raw_spin_lock_irqsave(&desc->lock, flags);
desc->chip->startup(irq);
raw_spin_unlock_irqrestore(&desc->lock, flags);
}
}
}
/* this is not called anywhere currently */
static void iseries_shutdown_IRQ(unsigned int irq)
{
u32 bus, dev_id, function, mask;
const u32 sub_bus = 0;
unsigned int rirq = (unsigned int)irq_map[irq].hwirq;
/* irq should be locked by the caller */
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Invalidate the IRQ number in the bridge */
HvCallXm_connectBusUnit(bus, sub_bus, dev_id, 0);
/* Mask bridge interrupts in the FISR */
mask = 0x01010000 << function;
HvCallPci_maskFisr(bus, sub_bus, dev_id, mask);
}
/*
* This will be called by device drivers (via disable_IRQ)
* to disable INTA in the bridge interrupt status register.
*/
static void iseries_disable_IRQ(unsigned int irq)
{
u32 bus, dev_id, function, mask;
const u32 sub_bus = 0;
unsigned int rirq = (unsigned int)irq_map[irq].hwirq;
/* The IRQ has already been locked by the caller */
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
dev_id = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Mask secondary INTA */
mask = 0x80000000;
HvCallPci_maskInterrupts(bus, sub_bus, dev_id, mask);
}
static void iseries_end_IRQ(unsigned int irq)
{
unsigned int rirq = (unsigned int)irq_map[irq].hwirq;
HvCallPci_eoi(REAL_IRQ_TO_BUS(rirq), REAL_IRQ_TO_SUBBUS(rirq),
(REAL_IRQ_TO_IDSEL(rirq) << 4) + REAL_IRQ_TO_FUNC(rirq));
}
static struct irq_chip iseries_pic = {
.name = "iSeries",
.startup = iseries_startup_IRQ,
.shutdown = iseries_shutdown_IRQ,
.unmask = iseries_enable_IRQ,
.mask = iseries_disable_IRQ,
.eoi = iseries_end_IRQ
};
/*
* This is called out of iSeries_scan_slot to allocate an IRQ for an EADS slot
* It calculates the irq value for the slot.
* Note that sub_bus is always 0 (at the moment at least).
*/
int __init iSeries_allocate_IRQ(HvBusNumber bus,
HvSubBusNumber sub_bus, u32 bsubbus)
{
unsigned int realirq;
u8 idsel = ISERIES_GET_DEVICE_FROM_SUBBUS(bsubbus);
u8 function = ISERIES_GET_FUNCTION_FROM_SUBBUS(bsubbus);
realirq = (((((sub_bus << 8) + (bus - 1)) << 3) + (idsel - 1)) << 3)
+ function;
return irq_create_mapping(NULL, realirq);
}
#endif /* CONFIG_PCI */
/*
* Get the next pending IRQ.
*/
unsigned int iSeries_get_irq(void)
{
int irq = NO_IRQ_IGNORE;
#ifdef CONFIG_SMP
if (get_lppaca()->int_dword.fields.ipi_cnt) {
get_lppaca()->int_dword.fields.ipi_cnt = 0;
iSeries_smp_message_recv();
}
#endif /* CONFIG_SMP */
if (hvlpevent_is_pending())
process_hvlpevents();
#ifdef CONFIG_PCI
if (num_pending_irqs) {
spin_lock(&pending_irqs_lock);
for (irq = 0; irq < NR_IRQS; irq++) {
if (pending_irqs[irq]) {
pending_irqs[irq]--;
num_pending_irqs--;
break;
}
}
spin_unlock(&pending_irqs_lock);
if (irq >= NR_IRQS)
irq = NO_IRQ_IGNORE;
}
#endif
return irq;
}
#ifdef CONFIG_PCI
static int iseries_irq_host_map(struct irq_host *h, unsigned int virq,
irq_hw_number_t hw)
{
set_irq_chip_and_handler(virq, &iseries_pic, handle_fasteoi_irq);
return 0;
}
static int iseries_irq_host_match(struct irq_host *h, struct device_node *np)
{
/* Match all */
return 1;
}
static struct irq_host_ops iseries_irq_host_ops = {
.map = iseries_irq_host_map,
.match = iseries_irq_host_match,
};
/*
* This is called by init_IRQ. set in ppc_md.init_IRQ by iSeries_setup.c
* It must be called before the bus walk.
*/
void __init iSeries_init_IRQ(void)
{
/* Register PCI event handler and open an event path */
struct irq_host *host;
int ret;
/*
* The Hypervisor only allows us up to 256 interrupt
* sources (the irq number is passed in a u8).
*/
irq_set_virq_count(256);
/* Create irq host. No need for a revmap since HV will give us
* back our virtual irq number
*/
host = irq_alloc_host(NULL, IRQ_HOST_MAP_NOMAP, 0,
&iseries_irq_host_ops, 0);
BUG_ON(host == NULL);
irq_set_default_host(host);
ret = HvLpEvent_registerHandler(HvLpEvent_Type_PciIo,
&pci_event_handler);
if (ret == 0) {
ret = HvLpEvent_openPath(HvLpEvent_Type_PciIo, 0);
if (ret != 0)
printk(KERN_ERR "iseries_init_IRQ: open event path "
"failed with rc 0x%x\n", ret);
} else
printk(KERN_ERR "iseries_init_IRQ: register handler "
"failed with rc 0x%x\n", ret);
}
#endif /* CONFIG_PCI */
