arch/m68k/sun3x/prom.c

Source file repositories/reference/linux-study-clean/arch/m68k/sun3x/prom.c

File Facts

System
Linux kernel
Corpus path
arch/m68k/sun3x/prom.c
Extension
.c
Size
3668 bytes
Lines
165
Domain
Architecture Layer
Bucket
arch/m68k
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

// SPDX-License-Identifier: GPL-2.0
/* Prom access routines for the sun3x */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/tty.h>
#include <linux/console.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/string.h>

#include <asm/page.h>
#include <asm/setup.h>
#include <asm/traps.h>
#include <asm/sun3xprom.h>
#include <asm/idprom.h>
#include <asm/sun3ints.h>
#include <asm/openprom.h>
#include <asm/machines.h>

void (*sun3x_putchar)(int);
int (*sun3x_getchar)(void);
int (*sun3x_mayget)(void);
int (*sun3x_mayput)(int);
void (*sun3x_prom_reboot)(void);
e_vector sun3x_prom_abort;
struct linux_romvec *romvec;

/* prom vector table */
e_vector *sun3x_prom_vbr;

/* Handle returning to the prom */
static void sun3x_halt(void)
{
	unsigned long flags;

	/* Disable interrupts while we mess with things */
	local_irq_save(flags);

	/* Restore prom vbr */
	asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));

	/* Restore prom NMI clock */
//	sun3x_disable_intreg(5);
	sun3_enable_irq(7);

	/* Let 'er rip */
	asm volatile ("trap #14");

	/* Restore everything */
	sun3_disable_irq(7);
	sun3_enable_irq(5);

	asm volatile ("movec %0,%%vbr" : : "r" ((void*)vectors));
	local_irq_restore(flags);
}

void sun3x_reboot(void)
{
	/* This never returns, don't bother saving things */
	local_irq_disable();

	/* Restore prom vbr */
	asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));

	/* Restore prom NMI clock */
	sun3_disable_irq(5);
	sun3_enable_irq(7);

	/* Let 'er rip */
	(*romvec->pv_reboot)("vmlinux");
}

static void sun3x_prom_write(struct console *co, const char *s,
                             unsigned int count)
{
	while (count--) {
		if (*s == '\n')
			sun3x_putchar('\r');
		sun3x_putchar(*s++);
	}
}

/* debug console - write-only */

static struct console sun3x_debug = {
	.name	= "debug",
	.write	= sun3x_prom_write,
	.flags	= CON_PRINTBUFFER,
	.index	= -1,

Annotation

Implementation Notes