/*
* This module supports the iSeries PCI bus interrupt handling
* Copyright (C) 20yy <Robert L Holtorf> <IBM Corp>
*
* 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/ide.h>
#include <linux/irq.h>
#include <linux/spinlock.h>
#include <asm/ppcdebug.h>
#include <asm/iSeries/HvCallPci.h>
#include <asm/iSeries/HvCallXm.h>
#include <asm/iSeries/iSeries_irq.h>
/* This maps virtual irq numbers to real irqs */
unsigned int virt_irq_to_real_map[NR_IRQS];
/* The next available virtual irq number */
/* Note: the pcnet32 driver assumes irq numbers < 2 aren't valid. :( */
static int next_virtual_irq = 2;
/* This is called by init_IRQ. set in ppc_md.init_IRQ by iSeries_setup.c */
void __init iSeries_init_IRQ(void)
{
/* Register PCI event handler and open an event path */
XmPciLpEvent_init();
}
#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, deviceId, function, mask;
const u32 subBus = 0;
unsigned int rirq = virt_irq_to_real_map[irq];
/* The IRQ has already been locked by the caller */
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Unmask secondary INTA */
mask = 0x80000000;
HvCallPci_unmaskInterrupts(bus, subBus, deviceId, mask);
PPCDBG(PPCDBG_BUSWALK, "iSeries_enable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
bus, subBus, deviceId, irq);
}
/* This is called by iSeries_activate_IRQs */
static unsigned int iSeries_startup_IRQ(unsigned int irq)
{
u32 bus, deviceId, function, mask;
const u32 subBus = 0;
unsigned int rirq = virt_irq_to_real_map[irq];
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Link the IRQ number to the bridge */
HvCallXm_connectBusUnit(bus, subBus, deviceId, irq);
/* Unmask bridge interrupts in the FISR */
mask = 0x01010000 << function;
HvCallPci_unmaskFisr(bus, subBus, deviceId, 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) {
irq_desc_t *desc = get_irq_desc(irq);
if (desc && desc->handler && desc->handler->startup) {
spin_lock_irqsave(&desc->lock, flags);
desc->handler->startup(irq);
spin_unlock_irqrestore(&desc->lock, flags);
}
}
}
/* this is not called anywhere currently */
static void iSeries_shutdown_IRQ(unsigned int irq)
{
u32 bus, deviceId, function, mask;
const u32 subBus = 0;
unsigned int rirq = virt_irq_to_real_map[irq];
/* irq should be locked by the caller */
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Invalidate the IRQ number in the bridge */
HvCallXm_connectBusUnit(bus, subBus, deviceId, 0);
/* Mask bridge interrupts in the FISR */
mask = 0x01010000 << function;
HvCallPci_maskFisr(bus, subBus, deviceId, 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, deviceId, function, mask;
const u32 subBus = 0;
unsigned int rirq = virt_irq_to_real_map[irq];
/* The IRQ has already been locked by the caller */
bus = REAL_IRQ_TO_BUS(rirq);
function = REAL_IRQ_TO_FUNC(rirq);
deviceId = (REAL_IRQ_TO_IDSEL(rirq) << 4) + function;
/* Mask secondary INTA */
mask = 0x80000000;
HvCallPci_maskInterrupts(bus, subBus, deviceId, mask);
PPCDBG(PPCDBG_BUSWALK, "iSeries_disable_IRQ 0x%02X.%02X.%02X 0x%04X\n",
bus, subBus, deviceId, irq);
}
/*
* Need to define this so ppc_irq_dispatch_handler will NOT call
* enable_IRQ at the end of interrupt handling. However, this does
* nothing because there is not enough information provided to do
* the EOI HvCall. This is done by XmPciLpEvent.c
*/
static void iSeries_end_IRQ(unsigned int irq)
{
}
static hw_irq_controller iSeries_IRQ_handler = {
.typename = "iSeries irq controller",
.startup = iSeries_startup_IRQ,
.shutdown = iSeries_shutdown_IRQ,
.enable = iSeries_enable_IRQ,
.disable = iSeries_disable_IRQ,
.end = 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 subBusNumber is always 0 (at the moment at least).
*/
int __init iSeries_allocate_IRQ(HvBusNumber busNumber,
HvSubBusNumber subBusNumber, HvAgentId deviceId)
{
unsigned int realirq, virtirq;
u8 idsel = (deviceId >> 4);
u8 function = deviceId & 7;
virtirq = next_virtual_irq++;
realirq = ((busNumber - 1) << 6) + ((idsel - 1) << 3) + function;
virt_irq_to_real_map[virtirq] = realirq;
irq_desc[virtirq].handler = &iSeries_IRQ_handler;
return virtirq;
}
