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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1992 Linus Torvalds
* Copyright (C) 1994 - 2000 Ralf Baechle
*/
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <asm/io.h>
#include <asm/sni.h>
spinlock_t pciasic_lock = SPIN_LOCK_UNLOCKED;
extern asmlinkage void sni_rm200_pci_handle_int(void);
extern void do_IRQ(int irq, struct pt_regs *regs);
static void enable_pciasic_irq(unsigned int irq);
static unsigned int startup_pciasic_irq(unsigned int irq)
{
enable_pciasic_irq(irq);
return 0; /* never anything pending */
}
#define shutdown_pciasic_irq disable_pciasic_irq
void disable_pciasic_irq(unsigned int irq)
{
unsigned int mask = ~(1 << (irq - PCIMT_IRQ_INT2));
unsigned long flags;
spin_lock_irqsave(&pciasic_lock, flags);
*(volatile u8 *) PCIMT_IRQSEL &= mask;
spin_unlock_irqrestore(&pciasic_lock, flags);
}
static void enable_pciasic_irq(unsigned int irq)
{
unsigned int mask = 1 << (irq - PCIMT_IRQ_INT2);
unsigned long flags;
spin_lock_irqsave(&pciasic_lock, flags);
*(volatile u8 *) PCIMT_IRQSEL |= mask;
spin_unlock_irqrestore(&pciasic_lock, flags);
}
#define mask_and_ack_pciasic_irq disable_pciasic_irq
static void end_pciasic_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
enable_pciasic_irq(irq);
}
static struct hw_interrupt_type pciasic_irq_type = {
"PCIASIC",
startup_pciasic_irq,
shutdown_pciasic_irq,
enable_pciasic_irq,
disable_pciasic_irq,
mask_and_ack_pciasic_irq,
end_pciasic_irq,
NULL
};
/*
* hwint0 should deal with MP agent, ASIC PCI, EISA NMI and debug
* button interrupts. Later ...
*/
void pciasic_hwint0(struct pt_regs *regs)
{
panic("Received int0 but no handler yet ...");
}
/* This interrupt was used for the com1 console on the first prototypes. */
void pciasic_hwint2(struct pt_regs *regs)
{
/* I think this shouldn't happen on production machines. */
panic("hwint2 and no handler yet");
}
/* hwint5 is the r4k count / compare interrupt */
void pciasic_hwint5(struct pt_regs *regs)
{
panic("hwint5 and no handler yet");
}
static inline int ls1bit8(unsigned int x)
{
int b = 8, s;
x <<= 24;
s = 4; if ((x & 0x0f) == 0) s = 0; b -= s; x <<= s;
s = 2; if ((x & 0x03) == 0) s = 0; b -= s; x <<= s;
s = 1; if ((x & 0x01) == 0) s = 0; b -= s;
return b;
}
/*
* hwint 1 deals with EISA and SCSI interrupts,
* hwint 3 should deal with the PCI A - D interrupts,
* hwint 4 is used for only the onboard PCnet 32.
*/
void pciasic_hwint134(struct pt_regs *regs)
{
u8 pend = *(volatile char *)PCIMT_CSITPEND;
int irq;
irq = PCIMT_IRQ_INT2 + ls1bit8(pend);
if (irq == PCIMT_IRQ_EISA) {
pend = *(volatile char *)PCIMT_INT_ACKNOWLEDGE;
if (!(pend ^ 0xff))
return;
}
do_IRQ(irq, regs);
return;
}
void __init init_pciasic(void)
{
unsigned int flags;
spin_lock_irqsave(&pciasic_lock, flags);
* (volatile u8 *) PCIMT_IRQSEL =
IT_EISA | IT_INTA | IT_INTB | IT_INTC | IT_INTD;
spin_unlock_irqrestore(&pciasic_lock, flags);
}
/*
* On systems with i8259-style interrupt controllers we assume for
* driver compatibility reasons interrupts 0 - 15 to be the i8295
* interrupts even if the hardware uses a different interrupt numbering.
*/
void __init init_IRQ (void)
{
int i;
set_except_vector(0, sni_rm200_pci_handle_int);
init_generic_irq();
init_i8259_irqs(); /* Integrated i8259 */
init_pciasic();
/* Actually we've got more interrupts to handle ... */
for (i = PCIMT_IRQ_INT2; i <= PCIMT_IRQ_ETHERNET; i++) {
irq_desc[i].status = IRQ_DISABLED;
irq_desc[i].action = 0;
irq_desc[i].depth = 1;
irq_desc[i].handler = &pciasic_irq_type;
}
}
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