arch/mips/ath25/ar2315.c

Source file repositories/reference/linux-study-clean/arch/mips/ath25/ar2315.c

File Facts

System
Linux kernel
Corpus path
arch/mips/ath25/ar2315.c
Extension
.c
Size
9548 bytes
Lines
363
Domain
Architecture Layer
Bucket
arch/mips
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/init.h>
#include <linux/kernel.h>
#include <linux/bitops.h>
#include <linux/irqdomain.h>
#include <linux/interrupt.h>
#include <linux/memblock.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <asm/bootinfo.h>
#include <asm/reboot.h>
#include <asm/time.h>

#include <ath25_platform.h>

#include "devices.h"
#include "ar2315.h"
#include "ar2315_regs.h"

static void __iomem *ar2315_rst_base;
static struct irq_domain *ar2315_misc_irq_domain;

static inline u32 ar2315_rst_reg_read(u32 reg)
{
	return __raw_readl(ar2315_rst_base + reg);
}

static inline void ar2315_rst_reg_write(u32 reg, u32 val)
{
	__raw_writel(val, ar2315_rst_base + reg);
}

static inline void ar2315_rst_reg_mask(u32 reg, u32 mask, u32 val)
{
	u32 ret = ar2315_rst_reg_read(reg);

	ret &= ~mask;
	ret |= val;
	ar2315_rst_reg_write(reg, ret);
}

static irqreturn_t ar2315_ahb_err_handler(int cpl, void *dev_id)
{
	ar2315_rst_reg_write(AR2315_AHB_ERR0, AR2315_AHB_ERROR_DET);
	ar2315_rst_reg_read(AR2315_AHB_ERR1);

	pr_emerg("AHB fatal error\n");
	machine_restart("AHB error"); /* Catastrophic failure */

	return IRQ_HANDLED;
}

static void ar2315_misc_irq_handler(struct irq_desc *desc)
{
	u32 pending = ar2315_rst_reg_read(AR2315_ISR) &
		      ar2315_rst_reg_read(AR2315_IMR);
	unsigned nr;
	int ret = 0;

	if (pending) {
		struct irq_domain *domain = irq_desc_get_handler_data(desc);

		nr = __ffs(pending);

		if (nr == AR2315_MISC_IRQ_GPIO)
			ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_GPIO);
		else if (nr == AR2315_MISC_IRQ_WATCHDOG)
			ar2315_rst_reg_write(AR2315_ISR, AR2315_ISR_WD);

		ret = generic_handle_domain_irq(domain, nr);
	}

	if (!pending || ret)
		spurious_interrupt();
}

static void ar2315_misc_irq_unmask(struct irq_data *d)
{
	ar2315_rst_reg_mask(AR2315_IMR, 0, BIT(d->hwirq));
}

static void ar2315_misc_irq_mask(struct irq_data *d)
{
	ar2315_rst_reg_mask(AR2315_IMR, BIT(d->hwirq), 0);
}

static struct irq_chip ar2315_misc_irq_chip = {
	.name		= "ar2315-misc",
	.irq_unmask	= ar2315_misc_irq_unmask,
	.irq_mask	= ar2315_misc_irq_mask,
};

Annotation

Implementation Notes