/*
* Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000, 2001, 2004 MIPS Technologies, Inc.
* Copyright (C) 2001 Ralf Baechle
*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope 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.
*
* Routines for generic manipulation of the interrupts found on the MIPS
* Malta board.
* The interrupt controller is located in the South Bridge a PIIX4 device
* with two internal 82C95 interrupt controllers.
*/
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include <asm/i8259.h>
#include <asm/irq_cpu.h>
#include <asm/io.h>
#include <asm/irq_regs.h>
#include <asm/mips-boards/malta.h>
#include <asm/mips-boards/maltaint.h>
#include <asm/mips-boards/piix4.h>
#include <asm/gt64120.h>
#include <asm/mips-boards/generic.h>
#include <asm/mips-boards/msc01_pci.h>
#include <asm/msc01_ic.h>
static DEFINE_SPINLOCK(mips_irq_lock);
static inline int mips_pcibios_iack(void)
{
int irq;
u32 dummy;
/*
* Determine highest priority pending interrupt by performing
* a PCI Interrupt Acknowledge cycle.
*/
switch (mips_revision_sconid) {
case MIPS_REVISION_SCON_SOCIT:
case MIPS_REVISION_SCON_ROCIT:
case MIPS_REVISION_SCON_SOCITSC:
case MIPS_REVISION_SCON_SOCITSCP:
MSC_READ(MSC01_PCI_IACK, irq);
irq &= 0xff;
break;
case MIPS_REVISION_SCON_GT64120:
irq = GT_READ(GT_PCI0_IACK_OFS);
irq &= 0xff;
break;
case MIPS_REVISION_SCON_BONITO:
/* The following will generate a PCI IACK cycle on the
* Bonito controller. It's a little bit kludgy, but it
* was the easiest way to implement it in hardware at
* the given time.
*/
BONITO_PCIMAP_CFG = 0x20000;
/* Flush Bonito register block */
dummy = BONITO_PCIMAP_CFG;
iob(); /* sync */
irq = readl((u32 *)_pcictrl_bonito_pcicfg);
iob(); /* sync */
irq &= 0xff;
BONITO_PCIMAP_CFG = 0;
break;
default:
printk("Unknown system controller.\n");
return -1;
}
return irq;
}
static inline int get_int(void)
{
unsigned long flags;
int irq;
spin_lock_irqsave(&mips_irq_lock, flags);
irq = mips_pcibios_iack();
/*
* The only way we can decide if an interrupt is spurious
* is by checking the 8259 registers. This needs a spinlock
* on an SMP system, so leave it up to the generic code...
*/
spin_unlock_irqrestore(&mips_irq_lock, flags);
return irq;
}
static void malta_hw0_irqdispatch(void)
{
int irq;
irq = get_int();
if (irq < 0) {
return; /* interrupt has already been cleared */
}
do_IRQ(MALTA_INT_BASE + irq);
}
static void corehi_irqdispatch(void)
{
unsigned int intedge, intsteer, pcicmd, pcibadaddr;
unsigned int pcimstat, intisr, inten, intpol;
unsigned int intrcause,datalo,datahi;
struct pt_regs *regs = get_irq_regs();
printk("CoreHI interrupt, shouldn't happen, so we die here!!!\n");
printk("epc : %08lx\nStatus: %08lx\n"
"Cause : %08lx\nbadVaddr : %08lx\n",
regs->cp0_epc, regs->cp0_status,
regs->cp0_cause, regs->cp0_badvaddr);
/* Read all the registers and then print them as there is a
problem with interspersed printk's upsetting the Bonito controller.
Do it for the others too.
*/
switch (mips_revision_sconid) {
case MIPS_REVISION_SCON_SOCIT:
case MIPS_REVISION_SCON_ROCIT:
case MIPS_REVISION_SCON_SOCITSC:
case MIPS_REVISION_SCON_SOCITSCP:
ll_msc_irq();
break;
case MIPS_REVISION_SCON_GT64120:
intrcause = GT_READ(GT_INTRCAUSE_OFS);
datalo = GT_READ(GT_CPUERR_ADDRLO_OFS);
datahi = GT_READ(GT_CPUERR_ADDRHI_OFS);
printk("GT_INTRCAUSE = %08x\n", intrcause);
printk("GT_CPUERR_ADDR = %02x%08x\n", datahi, datalo);
break;
case MIPS_REVISION_SCON_BONITO:
pcibadaddr = BONITO_PCIBADADDR;
pcimstat = BONITO_PCIMSTAT;
intisr = BONITO_INTISR;
inten = BONITO_INTEN;
intpol = BONITO_INTPOL;
intedge = BONITO_INTEDGE;
intsteer = BONITO_INTSTEER;
pcicmd = BONITO_PCICMD;
printk("BONITO_INTISR = %08x\n", intisr);
printk("BONITO_INTEN = %08x\n", inten);
printk("BONITO_INTPOL = %08x\n", intpol);
printk("BONITO_INTEDGE = %08x\n", intedge);
printk("BONITO_INTSTEER = %08x\n", intsteer);
printk("BONITO_PCICMD = %08x\n", pcicmd);
printk("BONITO_PCIBADADDR = %08x\n", pcibadaddr);
printk("BONITO_PCIMSTAT = %08x\n", pcimstat);
break;
}
/* We die here*/
die("CoreHi interrupt", regs);
}
static inline int clz(unsigned long x)
{
__asm__(
" .set push \n"
" .set mips32 \n"
" clz %0, %1 \n"
" .set pop \n"
: "=r" (x)
: "r" (x));
return x;
}
/*
* Version of ffs that only looks at bits 12..15.
*/
static inline unsigned int irq_ffs(unsigned int pending)
{
#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
return -clz(pending) + 31 - CAUSEB_IP;
#else
unsigned int a0 = 7;
unsigned int t0;
t0 = pending & 0xf000;
t0 = t0 < 1;
t0 = t0 << 2;
a0 = a0 - t0;
pending = pending << t0;
t0 = pending & 0xc000;
t0 = t0 < 1;
t0 = t0 << 1;
a0 = a0 - t0;
pending = pending << t0;
t0 = pending & 0x8000;
t0 = t0 < 1;
//t0 = t0 << 2;
a0 = a0 - t0;
//pending = pending << t0;
return a0;
#endif
}
/*
* IRQs on the Malta board look basically (barring software IRQs which we
* don't use at all and all external interrupt sources are combined together
* on hardware interrupt 0 (MIPS IRQ 2)) like:
*
* MIPS IRQ Source
* -------- ------
* 0 Software (ignored)
* 1 Software (ignored)
* 2 Combined hardware interrupt (hw0)
* 3 Hardware (ignored)
* 4 Hardware (ignored)
* 5 Hardware (ignored)
* 6 Hardware (ignored)
* 7 R4k timer (what we use)
*
* We handle the IRQ according to _our_ priority which is:
*
* Highest ---- R4k Timer
* Lowest ---- Combined hardware interrupt
*
* then we just return, if multiple IRQs are pending then we will just take
* another exception, big deal.
*/
asmlinkage void plat_irq_dispatch(void)
{
unsigned int pending = read_c0_cause() & read_c0_status() & ST0_IM;
int irq;
irq = irq_ffs(pending);
if (irq == MIPSCPU_INT_I8259A)
malta_hw0_irqdispatch();
else if (irq >= 0)
do_IRQ(MIPS_CPU_IRQ_BASE + irq);
else
spurious_interrupt();
}
static struct irqaction i8259irq = {
.handler = no_action,
.name = "XT-PIC cascade"
};
static struct irqaction corehi_irqaction = {
.handler = no_action,
.name = "CoreHi"
};
msc_irqmap_t __initdata msc_irqmap[] = {
{MSC01C_INT_TMR, MSC01_IRQ_EDGE, 0},
{MSC01C_INT_PCI, MSC01_IRQ_LEVEL, 0},
};
int __initdata msc_nr_irqs = ARRAY_SIZE(msc_irqmap);
msc_irqmap_t __initdata msc_eicirqmap[] = {
{MSC01E_INT_SW0, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_SW1, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_I8259A, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_SMI, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_COREHI, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_CORELO, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_TMR, MSC01_IRQ_EDGE, 0},
{MSC01E_INT_PCI, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_PERFCTR, MSC01_IRQ_LEVEL, 0},
{MSC01E_INT_CPUCTR, MSC01_IRQ_LEVEL, 0}
};
int __initdata msc_nr_eicirqs = ARRAY_SIZE(msc_eicirqmap);
void __init arch_init_irq(void)
{
init_i8259_irqs();
if (!cpu_has_veic)
mips_cpu_irq_init();
switch(mips_revision_sconid) {
case MIPS_REVISION_SCON_SOCIT:
case MIPS_REVISION_SCON_ROCIT:
if (cpu_has_veic)
init_msc_irqs(MIPS_MSC01_IC_REG_BASE, MSC01E_INT_BASE, msc_eicirqmap, msc_nr_eicirqs);
else
init_msc_irqs(MIPS_MSC01_IC_REG_BASE, MSC01C_INT_BASE, msc_irqmap, msc_nr_irqs);
break;
case MIPS_REVISION_SCON_SOCITSC:
case MIPS_REVISION_SCON_SOCITSCP:
if (cpu_has_veic)
init_msc_irqs(MIPS_SOCITSC_IC_REG_BASE, MSC01E_INT_BASE, msc_eicirqmap, msc_nr_eicirqs);
else
init_msc_irqs(MIPS_SOCITSC_IC_REG_BASE, MSC01C_INT_BASE, msc_irqmap, msc_nr_irqs);
}
if (cpu_has_veic) {
set_vi_handler(MSC01E_INT_I8259A, malta_hw0_irqdispatch);
set_vi_handler(MSC01E_INT_COREHI, corehi_irqdispatch);
setup_irq(MSC01E_INT_BASE+MSC01E_INT_I8259A, &i8259irq);
setup_irq(MSC01E_INT_BASE+MSC01E_INT_COREHI, &corehi_irqaction);
}
else if (cpu_has_vint) {
set_vi_handler(MIPSCPU_INT_I8259A, malta_hw0_irqdispatch);
set_vi_handler(MIPSCPU_INT_COREHI, corehi_irqdispatch);
#ifdef CONFIG_MIPS_MT_SMTC
setup_irq_smtc(MIPS_CPU_IRQ_BASE+MIPSCPU_INT_I8259A, &i8259irq,
(0x100 << MIPSCPU_INT_I8259A));
setup_irq_smtc(MIPS_CPU_IRQ_BASE+MIPSCPU_INT_COREHI,
&corehi_irqaction, (0x100 << MIPSCPU_INT_COREHI));
/*
* Temporary hack to ensure that the subsidiary device
* interrupts coing in via the i8259A, but associated
* with low IRQ numbers, will restore the Status.IM
* value associated with the i8259A.
*/
{
int i;
for (i = 0; i < 16; i++)
irq_hwmask[i] = (0x100 << MIPSCPU_INT_I8259A);
}
#else /* Not SMTC */
setup_irq(MIPS_CPU_IRQ_BASE+MIPSCPU_INT_I8259A, &i8259irq);
setup_irq(MIPS_CPU_IRQ_BASE+MIPSCPU_INT_COREHI, &corehi_irqaction);
#endif /* CONFIG_MIPS_MT_SMTC */
}
else {
setup_irq(MIPS_CPU_IRQ_BASE+MIPSCPU_INT_I8259A, &i8259irq);
setup_irq(MIPS_CPU_IRQ_BASE+MIPSCPU_INT_COREHI, &corehi_irqaction);
}
}
