linux/arch/ppc/syslib/ppc8xx_pic.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

131 lines
3.3 KiB
C

#include <linux/config.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/interrupt.h>
#include <asm/irq.h>
#include <asm/8xx_immap.h>
#include <asm/mpc8xx.h>
#include "ppc8xx_pic.h"
extern int cpm_get_irq(struct pt_regs *regs);
/* The 8xx internal interrupt controller. It is usually
* the only interrupt controller. Some boards, like the MBX and
* Sandpoint have the 8259 as a secondary controller. Depending
* upon the processor type, the internal controller can have as
* few as 16 interrups or as many as 64. We could use the
* "clear_bit()" and "set_bit()" functions like other platforms,
* but they are overkill for us.
*/
static void m8xx_mask_irq(unsigned int irq_nr)
{
int bit, word;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
ppc_cached_irq_mask[word];
}
static void m8xx_unmask_irq(unsigned int irq_nr)
{
int bit, word;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] |= (1 << (31-bit));
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
ppc_cached_irq_mask[word];
}
static void m8xx_end_irq(unsigned int irq_nr)
{
if (!(irq_desc[irq_nr].status & (IRQ_DISABLED|IRQ_INPROGRESS))
&& irq_desc[irq_nr].action) {
int bit, word;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] |= (1 << (31-bit));
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
ppc_cached_irq_mask[word];
}
}
static void m8xx_mask_and_ack(unsigned int irq_nr)
{
int bit, word;
bit = irq_nr & 0x1f;
word = irq_nr >> 5;
ppc_cached_irq_mask[word] &= ~(1 << (31-bit));
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_simask =
ppc_cached_irq_mask[word];
((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sipend = 1 << (31-bit);
}
struct hw_interrupt_type ppc8xx_pic = {
.typename = " 8xx SIU ",
.enable = m8xx_unmask_irq,
.disable = m8xx_mask_irq,
.ack = m8xx_mask_and_ack,
.end = m8xx_end_irq,
};
/*
* We either return a valid interrupt or -1 if there is nothing pending
*/
int
m8xx_get_irq(struct pt_regs *regs)
{
int irq;
/* For MPC8xx, read the SIVEC register and shift the bits down
* to get the irq number.
*/
irq = ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_sivec >> 26;
/*
* When we read the sivec without an interrupt to process, we will
* get back SIU_LEVEL7. In this case, return -1
*/
if (irq == CPM_INTERRUPT)
irq = CPM_IRQ_OFFSET + cpm_get_irq(regs);
#if defined(CONFIG_PCI)
else if (irq == ISA_BRIDGE_INT) {
int isa_irq;
if ((isa_irq = i8259_poll(regs)) >= 0)
irq = I8259_IRQ_OFFSET + isa_irq;
}
#endif /* CONFIG_PCI */
else if (irq == SIU_LEVEL7)
irq = -1;
return irq;
}
#if defined(CONFIG_MBX) && defined(CONFIG_PCI)
/* Only the MBX uses the external 8259. This allows us to catch standard
* drivers that may mess up the internal interrupt controllers, and also
* allow them to run without modification on the MBX.
*/
void mbx_i8259_action(int irq, void *dev_id, struct pt_regs *regs)
{
/* This interrupt handler never actually gets called. It is
* installed only to unmask the 8259 cascade interrupt in the SIU
* and to make the 8259 cascade interrupt visible in /proc/interrupts.
*/
}
#endif /* CONFIG_PCI */