static void atari_reset()

in atari/config.c [491:571]

• 62 lines of code
• 8 McCabe index (conditional complexity)

static void atari_reset(void)
{
	long tc_val = 0;
	long reset_addr;

	/*
	 * On the Medusa, phys. 0x4 may contain garbage because it's no
	 * ROM.  See above for explanation why we cannot use PTOV(4).
	 */
	reset_addr = MACH_IS_MEDUSA || MACH_IS_AB40 ? 0xe00030 :
		     *(unsigned long *) 0xff000004;

	/* reset ACIA for switch off OverScan, if it's active */
	if (atari_switches & ATARI_SWITCH_OVSC_IKBD)
		acia.key_ctrl = ACIA_RESET;
	if (atari_switches & ATARI_SWITCH_OVSC_MIDI)
		acia.mid_ctrl = ACIA_RESET;

	/* processor independent: turn off interrupts and reset the VBR;
	 * the caches must be left enabled, else prefetching the final jump
	 * instruction doesn't work.
	 */
	local_irq_disable();
	asm volatile ("movec	%0,%%vbr"
			: : "d" (0));

	if (CPU_IS_040_OR_060) {
		unsigned long jmp_addr040 = virt_to_phys(&&jmp_addr_label040);
		if (CPU_IS_060) {
			/* 68060: clear PCR to turn off superscalar operation */
			asm volatile ("\n"
				"	.chip 68060\n"
				"	movec %0,%%pcr\n"
				"	.chip 68k"
				: : "d" (0));
		}

		asm volatile ("\n"
			"	move.l	%0,%%d0\n"
			"	and.l	#0xff000000,%%d0\n"
			"	or.w	#0xe020,%%d0\n"   /* map 16 MB, enable, cacheable */
			"	.chip	68040\n"
			"	movec	%%d0,%%itt0\n"
			"	movec	%%d0,%%dtt0\n"
			"	.chip	68k\n"
			"	jmp	%0@"
			: : "a" (jmp_addr040)
			: "d0");
	jmp_addr_label040:
		asm volatile ("\n"
			"	moveq	#0,%%d0\n"
			"	nop\n"
			"	.chip	68040\n"
			"	cinva	%%bc\n"
			"	nop\n"
			"	pflusha\n"
			"	nop\n"
			"	movec	%%d0,%%tc\n"
			"	nop\n"
			/* the following setup of transparent translations is needed on the
			 * Afterburner040 to successfully reboot. Other machines shouldn't
			 * care about a different tt regs setup, they also didn't care in
			 * the past that the regs weren't turned off. */
			"	move.l	#0xffc000,%%d0\n" /* whole insn space cacheable */
			"	movec	%%d0,%%itt0\n"
			"	movec	%%d0,%%itt1\n"
			"	or.w	#0x40,%/d0\n" /* whole data space non-cacheable/ser. */
			"	movec	%%d0,%%dtt0\n"
			"	movec	%%d0,%%dtt1\n"
			"	.chip	68k\n"
			"	jmp	%0@"
			: /* no outputs */
			: "a" (reset_addr)
			: "d0");
	} else
		asm volatile ("\n"
			"	pmove	%0,%%tc\n"
			"	jmp	%1@"
			: /* no outputs */
			: "m" (tc_val), "a" (reset_addr));
}