arch/sh/boards/mach-se/7724/irq.c

Source file repositories/reference/linux-study-clean/arch/sh/boards/mach-se/7724/irq.c

File Facts

System
Linux kernel
Corpus path
arch/sh/boards/mach-se/7724/irq.c
Extension
.c
Size
3452 bytes
Lines
144
Domain
Architecture Layer
Bucket
arch/sh
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

struct fpga_irq {
	unsigned long  sraddr;
	unsigned long  mraddr;
	unsigned short mask;
	unsigned int   base;
};

static unsigned int fpga2irq(unsigned int irq)
{
	if (irq >= IRQ0_BASE &&
	    irq <= IRQ0_END)
		return IRQ0_IRQ;
	else if (irq >= IRQ1_BASE &&
		 irq <= IRQ1_END)
		return IRQ1_IRQ;
	else
		return IRQ2_IRQ;
}

static struct fpga_irq get_fpga_irq(unsigned int irq)
{
	struct fpga_irq set;

	switch (irq) {
	case IRQ0_IRQ:
		set.sraddr = IRQ0_SR;
		set.mraddr = IRQ0_MR;
		set.mask   = IRQ0_MASK;
		set.base   = IRQ0_BASE;
		break;
	case IRQ1_IRQ:
		set.sraddr = IRQ1_SR;
		set.mraddr = IRQ1_MR;
		set.mask   = IRQ1_MASK;
		set.base   = IRQ1_BASE;
		break;
	default:
		set.sraddr = IRQ2_SR;
		set.mraddr = IRQ2_MR;
		set.mask   = IRQ2_MASK;
		set.base   = IRQ2_BASE;
		break;
	}

	return set;
}

static void disable_se7724_irq(struct irq_data *data)
{
	unsigned int irq = data->irq;
	struct fpga_irq set = get_fpga_irq(fpga2irq(irq));
	unsigned int bit = irq - set.base;
	__raw_writew(__raw_readw(set.mraddr) | 0x0001 << bit, set.mraddr);
}

static void enable_se7724_irq(struct irq_data *data)
{
	unsigned int irq = data->irq;
	struct fpga_irq set = get_fpga_irq(fpga2irq(irq));
	unsigned int bit = irq - set.base;
	__raw_writew(__raw_readw(set.mraddr) & ~(0x0001 << bit), set.mraddr);
}

static struct irq_chip se7724_irq_chip __read_mostly = {
	.name		= "SE7724-FPGA",
	.irq_mask	= disable_se7724_irq,
	.irq_unmask	= enable_se7724_irq,
};

static void se7724_irq_demux(struct irq_desc *desc)
{
	unsigned int irq = irq_desc_get_irq(desc);
	struct fpga_irq set = get_fpga_irq(irq);
	unsigned short intv = __raw_readw(set.sraddr);
	unsigned int ext_irq = set.base;

	intv &= set.mask;

	for (; intv; intv >>= 1, ext_irq++) {
		if (!(intv & 1))
			continue;

		generic_handle_irq(ext_irq);
	}
}

/*
 * Initialize IRQ setting
 */
void __init init_se7724_IRQ(void)

Annotation

Implementation Notes