irq.c

ARM 嵌入式 系统 设计与实例开发 实验教材 二源码

/*
 *  arch/mips/ddb5476/irq.c -- NEC DDB Vrc-5476 interrupt routines
 *
 *  Copyright (C) 2000 Geert Uytterhoeven <[e-mail]>
 *                     Sony Software Development Center Europe (SDCE), Brussels
 */
#include <linux/config.h>
#include <linux/init.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>

#include <asm/io.h>
#include <asm/irq.h>
#include <asm/ptrace.h>
#include <asm/nile4.h>

extern void __init i8259_init(void);
extern void i8259_disable_irq(unsigned int irq_nr);
extern void i8259_enable_irq(unsigned int irq_nr);

extern asmlinkage void ddbIRQ(void);
extern asmlinkage void i8259_do_irq(int irq, struct pt_regs *regs);
extern asmlinkage void do_IRQ(int irq, struct pt_regs *regs);


void no_action(int cpl, void *dev_id, struct pt_regs *regs)
{
}


#define M1543_PNP_CONFIG	0x03f0	/* PnP Config Port */
#define M1543_PNP_INDEX		0x03f0	/* PnP Index Port */
#define M1543_PNP_DATA		0x03f1	/* PnP Data Port */

#define M1543_PNP_ALT_CONFIG	0x0370	/* Alternative PnP Config Port */
#define M1543_PNP_ALT_INDEX	0x0370	/* Alternative PnP Index Port */
#define M1543_PNP_ALT_DATA	0x0371	/* Alternative PnP Data Port */

#define M1543_INT1_MASTER_CTRL	0x0020	/* INT_1 (master) Control Register */
#define M1543_INT1_MASTER_MASK	0x0021	/* INT_1 (master) Mask Register */

#define M1543_INT1_SLAVE_CTRL	0x00a0	/* INT_1 (slave) Control Register */
#define M1543_INT1_SLAVE_MASK	0x00a1	/* INT_1 (slave) Mask Register */

#define M1543_INT1_MASTER_ELCR	0x04d0	/* INT_1 (master) Edge/Level Control */
#define M1543_INT1_SLAVE_ELCR	0x04d1	/* INT_1 (slave) Edge/Level Control */

static struct {
	struct resource m1543_config;
	struct resource pic_elcr;
} m1543_ioport = {
	{ "M1543 config", M1543_PNP_CONFIG, M1543_PNP_CONFIG + 1,
	  IORESOURCE_BUSY},
	{ "pic ELCR", M1543_INT1_MASTER_ELCR, M1543_INT1_MASTER_ELCR + 1,
	  IORESOURCE_BUSY}
};

static void m1543_irq_setup(void)
{
	/*
	 *  The ALI M1543 has 13 interrupt inputs, IRQ1..IRQ13.  Not all
	 *  the possible IO sources in the M1543 are in use by us.  We will
	 *  use the following mapping:
	 *
	 *      IRQ1  - keyboard (default set by M1543)
	 *      IRQ3  - reserved for UART B (default set by M1543) (note that
	 *              the schematics for the DDB Vrc-5476 board seem to 
	 *              indicate that IRQ3 is connected to the DS1386 
	 *              watchdog timer interrupt output so we might have 
	 *              a conflict)
	 *      IRQ4  - reserved for UART A (default set by M1543)
	 *      IRQ5  - parallel (default set by M1543)
	 *      IRQ8  - DS1386 time of day (RTC) interrupt
	 *      IRQ9  - USB (hardwired in ddb_setup)
	 *      IRQ10 - PMU (hardwired in ddb_setup)
	 *      IRQ12 - mouse
	 *      IRQ14,15 - IDE controller (need to be confirmed, jsun)
	 */

	/*
	 *  Assing mouse interrupt to IRQ12 
	 */

	/* Enter configuration mode */
	outb(0x51, M1543_PNP_CONFIG);
	outb(0x23, M1543_PNP_CONFIG);

	/* Select logical device 7 (Keyboard) */
	outb(0x07, M1543_PNP_INDEX);
	outb(0x07, M1543_PNP_DATA);

	/* Select IRQ12 */
	outb(0x72, M1543_PNP_INDEX);
	outb(0x0c, M1543_PNP_DATA);

	/* Leave configration mode */
	outb(0xbb, M1543_PNP_CONFIG);


	/* Initialize the 8259 PIC in the M1543 */
	i8259_init();

	/* Enable the interrupt cascade from M1543 */
	nile4_enable_irq(NILE4_INT_INTC);

	/* request io ports */
	if (request_resource(&ioport_resource, &m1543_ioport.m1543_config)
	    || request_resource(&ioport_resource, &m1543_ioport.pic_elcr)) {
		printk("m1543_irq_setup : requesting io ports failed.\n");
		for (;;);
	}
}

static void nile4_irq_setup(void)
{
	int i;

	/* Map all interrupts to CPU int #0 */
	nile4_map_irq_all(0);

	/* PCI INTA#-E# must be level triggered */
	nile4_set_pci_irq_level_or_edge(0, 1);
	nile4_set_pci_irq_level_or_edge(1, 1);
	nile4_set_pci_irq_level_or_edge(2, 1);
	nile4_set_pci_irq_level_or_edge(3, 1);

	/* PCI INTA#, B#, D# must be active low, INTC# must be active high */
	nile4_set_pci_irq_polarity(0, 0);
	nile4_set_pci_irq_polarity(1, 0);
	nile4_set_pci_irq_polarity(2, 1);
	nile4_set_pci_irq_polarity(3, 0);

	for (i = 0; i < 16; i++)
		nile4_clear_irq(i);

	/* Enable CPU int #0 */
	nile4_enable_irq_output(0);

	/* memory resource acquire in ddb_setup */
}


/*
 * IRQ2 is cascade interrupt to second interrupt controller
 */
static struct irqaction irq2 = { no_action, 0, 0, "cascade", NULL, NULL };


void disable_irq(unsigned int irq_nr)
{
	if (is_i8259_irq(irq_nr))
		i8259_disable_irq(irq_nr);
	else
		nile4_disable_irq(irq_to_nile4(irq_nr));
}

void enable_irq(unsigned int irq_nr)
{
	if (is_i8259_irq(irq_nr))
		i8259_enable_irq(irq_nr);
	else
		nile4_enable_irq(irq_to_nile4(irq_nr));
}

int table[16] = { 0, };

void ddb_local0_irqdispatch(struct pt_regs *regs)
{
	u32 mask;
	int nile4_irq;
#if 0
	volatile static int nesting = 0;
	if (nesting++ == 0)
		ddb5476_led_d3(1);
	ddb5476_led_hex(nesting < 16 ? nesting : 15);
#endif

	mask = nile4_get_irq_stat(0);
	nile4_clear_irq_mask(mask);

	/* Handle the timer interrupt first */
	if (mask & (1 << NILE4_INT_GPT)) {
		nile4_disable_irq(NILE4_INT_GPT);
		do_IRQ(nile4_to_irq(NILE4_INT_GPT), regs);
		nile4_enable_irq(NILE4_INT_GPT);
		mask &= ~(1 << NILE4_INT_GPT);
	}
	for (nile4_irq = 0; mask; nile4_irq++, mask >>= 1)
		if (mask & 1) {
			nile4_disable_irq(nile4_irq);
			if (nile4_irq == NILE4_INT_INTC) {
				int i8259_irq = nile4_i8259_iack();
				i8259_do_irq(i8259_irq, regs);
			} else {
				do_IRQ(nile4_to_irq(nile4_irq), regs);
			}
			nile4_enable_irq(nile4_irq);
		}
#if 0
	if (--nesting == 0)
		ddb5476_led_d3(0);
	ddb5476_led_hex(nesting < 16 ? nesting : 15);
#endif
}

void ddb_local1_irqdispatch(void)
{
	printk("ddb_local1_irqdispatch called\n");
}

void ddb_buserror_irq(void)
{
	printk("ddb_buserror_irq called\n");
}

void ddb_8254timer_irq(void)
{
	printk("ddb_8254timer_irq called\n");
}

void ddb_phantom_irq(unsigned long cause)
{
	printk("phantom interrupts detected : \n");
	printk("\tcause \t\t0x%08x\n", cause);
	printk("\tcause reg\t0x%08x\n",
	       read_32bit_cp0_register(CP0_CAUSE));
	printk("\tstatus reg\t0x%08x\n",
	       read_32bit_cp0_register(CP0_STATUS));
}

void __init ddb_irq_setup(void)
{
#ifdef CONFIG_REMOTE_DEBUG
	printk("Wait for gdb client connection ...\n");
	set_debug_traps();
	breakpoint();		/* you may move this line to whereever you want :-) */
#endif
	i8259_setup_irq(2, &irq2);

	nile4_irq_setup();
	m1543_irq_setup();

	/* we pin #0 - #4 (no internal timer) */
	change_cp0_status(ST0_IM,
	                  IE_IRQ0 | IE_IRQ1 | IE_IRQ2 | IE_IRQ3 | IE_IRQ4);

	set_except_vector(0, ddbIRQ);
}