arch/powerpc/platforms/8xx/pic.c

Source file repositories/reference/linux-study-clean/arch/powerpc/platforms/8xx/pic.c

File Facts

System
Linux kernel
Corpus path
arch/powerpc/platforms/8xx/pic.c
Extension
.c
Size
3636 bytes
Lines
157
Domain
Architecture Layer
Bucket
arch/powerpc
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/sched.h>
#include <linux/signal.h>
#include <linux/irq.h>
#include <linux/dma-mapping.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <asm/irq.h>
#include <asm/io.h>
#include <asm/8xx_immap.h>

#include "pic.h"


#define PIC_VEC_SPURRIOUS      15

static struct irq_domain *mpc8xx_pic_host;
static unsigned long mpc8xx_cached_irq_mask;
static sysconf8xx_t __iomem *siu_reg;

static inline unsigned long mpc8xx_irqd_to_bit(struct irq_data *d)
{
	return 0x80000000 >> irqd_to_hwirq(d);
}

static void mpc8xx_unmask_irq(struct irq_data *d)
{
	mpc8xx_cached_irq_mask |= mpc8xx_irqd_to_bit(d);
	out_be32(&siu_reg->sc_simask, mpc8xx_cached_irq_mask);
}

static void mpc8xx_mask_irq(struct irq_data *d)
{
	mpc8xx_cached_irq_mask &= ~mpc8xx_irqd_to_bit(d);
	out_be32(&siu_reg->sc_simask, mpc8xx_cached_irq_mask);
}

static void mpc8xx_ack(struct irq_data *d)
{
	out_be32(&siu_reg->sc_sipend, mpc8xx_irqd_to_bit(d));
}

static void mpc8xx_end_irq(struct irq_data *d)
{
	mpc8xx_cached_irq_mask |= mpc8xx_irqd_to_bit(d);
	out_be32(&siu_reg->sc_simask, mpc8xx_cached_irq_mask);
}

static int mpc8xx_set_irq_type(struct irq_data *d, unsigned int flow_type)
{
	/* only external IRQ senses are programmable */
	if ((flow_type & IRQ_TYPE_EDGE_FALLING) && !(irqd_to_hwirq(d) & 1)) {
		unsigned int siel = in_be32(&siu_reg->sc_siel);
		siel |= mpc8xx_irqd_to_bit(d);
		out_be32(&siu_reg->sc_siel, siel);
		irq_set_handler_locked(d, handle_edge_irq);
	}
	return 0;
}

static struct irq_chip mpc8xx_pic = {
	.name = "8XX SIU",
	.irq_unmask = mpc8xx_unmask_irq,
	.irq_mask = mpc8xx_mask_irq,
	.irq_ack = mpc8xx_ack,
	.irq_eoi = mpc8xx_end_irq,
	.irq_set_type = mpc8xx_set_irq_type,
};

unsigned int mpc8xx_get_irq(void)
{
	int irq;

	/* For MPC8xx, read the SIVEC register and shift the bits down
	 * to get the irq number.
	 */
	irq = in_be32(&siu_reg->sc_sivec) >> 26;

	if (irq == PIC_VEC_SPURRIOUS)
		return 0;

        return irq_find_mapping(mpc8xx_pic_host, irq);

}

static int mpc8xx_pic_host_map(struct irq_domain *h, unsigned int virq,
			  irq_hw_number_t hw)
{
	pr_debug("mpc8xx_pic_host_map(%d, 0x%lx)\n", virq, hw);

Annotation

Implementation Notes