Commit c0eaa453 authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Ingo Molnar
Browse files

x86: apic - introduce imcr_ helpers 



Impact: cleanup

Distinguish port writting magic into helpers with comments.

Signed-off-by: default avatarCyrill Gorcunov <gorcunov@openvz.org>
LKML-Reference: <20090412165058.535921550@openvz.org>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent edea7148

arch/x86/kernel/apic/apic.c

+25 −4
Original line number Diff line number Diff line
@@ -98,6 +98,29 @@ early_param("lapic", parse_lapic); 
/* Local APIC was disabled by the BIOS and enabled by the kernel */

static int enabled_via_apicbase;



/*

 * Handle interrupt mode configuration register (IMCR).

 * This register controls whether the interrupt signals

 * that reach the BSP come from the master PIC or from the

 * local APIC. Before entering Symmetric I/O Mode, either

 * the BIOS or the operating system must switch out of

 * PIC Mode by changing the IMCR.

 */

static inline imcr_pic_to_apic(void)

{

	/* select IMCR register */

	outb(0x70, 0x22);

	/* NMI and 8259 INTR go through APIC */

	outb(0x01, 0x23);

}



static inline imcr_apic_to_pic(void)

{

	/* select IMCR register */

	outb(0x70, 0x22);

	/* NMI and 8259 INTR go directly to BSP */

	outb(0x00, 0x23);

}

#endif



#ifdef CONFIG_X86_64
@@ -1727,8 +1750,7 @@ void __init connect_bsp_APIC(void) 
		 */

		apic_printk(APIC_VERBOSE, "leaving PIC mode, "

				"enabling APIC mode.\n");

		outb(0x70, 0x22);

		outb(0x01, 0x23);

		imcr_pic_to_apic();

	}

#endif

	if (apic->enable_apic_mode)
@@ -1756,8 +1778,7 @@ void disconnect_bsp_APIC(int virt_wire_setup) 
		 */

		apic_printk(APIC_VERBOSE, "disabling APIC mode, "

				"entering PIC mode.\n");

		outb(0x70, 0x22);

		outb(0x00, 0x23);

		imcr_apic_to_pic();

		return;

	}

#endif