Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0af2be0b authored by Andi Kleen's avatar Andi Kleen Committed by Linus Torvalds
Browse files

[PATCH] x86_64: Remove unique APIC/IO-APIC ID check 



It is unnecessary on modern Intel or AMD systems, and that is all we support
on x86-64

Also causes problems on various systems

Signed-off-by: default avatarAndi Kleen <ak@suse.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 622dcaf9

arch/x86_64/kernel/io_apic.c

+0 −70
Original line number Diff line number Diff line
@@ -1804,76 +1804,6 @@ device_initcall(ioapic_init_sysfs); 


#define IO_APIC_MAX_ID		0xFE



int __init io_apic_get_unique_id (int ioapic, int apic_id)

{

	union IO_APIC_reg_00 reg_00;

	static physid_mask_t apic_id_map;

	unsigned long flags;

	int i = 0;



	/*

	 * The P4 platform supports up to 256 APIC IDs on two separate APIC 

	 * buses (one for LAPICs, one for IOAPICs), where predecessors only 

	 * supports up to 16 on one shared APIC bus.

	 * 

	 * TBD: Expand LAPIC/IOAPIC support on P4-class systems to take full

	 *      advantage of new APIC bus architecture.

	 */



	if (physids_empty(apic_id_map))

		apic_id_map = phys_cpu_present_map;



	spin_lock_irqsave(&ioapic_lock, flags);

	reg_00.raw = io_apic_read(ioapic, 0);

	spin_unlock_irqrestore(&ioapic_lock, flags);



	if (apic_id >= IO_APIC_MAX_ID) {

		apic_printk(APIC_QUIET, KERN_WARNING "IOAPIC[%d]: Invalid apic_id %d, trying "

			"%d\n", ioapic, apic_id, reg_00.bits.ID);

		apic_id = reg_00.bits.ID;

	}



	/*

	 * Every APIC in a system must have a unique ID or we get lots of nice 

	 * 'stuck on smp_invalidate_needed IPI wait' messages.

	 */

	if (physid_isset(apic_id, apic_id_map)) {



		for (i = 0; i < IO_APIC_MAX_ID; i++) {

			if (!physid_isset(i, apic_id_map))

				break;

		}



		if (i == IO_APIC_MAX_ID)

			panic("Max apic_id exceeded!\n");



		apic_printk(APIC_VERBOSE, KERN_WARNING "IOAPIC[%d]: apic_id %d already used, "

			"trying %d\n", ioapic, apic_id, i);



		apic_id = i;

	} 



	physid_set(apic_id, apic_id_map);



	if (reg_00.bits.ID != apic_id) {

		reg_00.bits.ID = apic_id;



		spin_lock_irqsave(&ioapic_lock, flags);

		io_apic_write(ioapic, 0, reg_00.raw);

		reg_00.raw = io_apic_read(ioapic, 0);

		spin_unlock_irqrestore(&ioapic_lock, flags);



		/* Sanity check */

		if (reg_00.bits.ID != apic_id)

			panic("IOAPIC[%d]: Unable change apic_id!\n", ioapic);

	}



	apic_printk(APIC_VERBOSE,KERN_INFO "IOAPIC[%d]: Assigned apic_id %d\n", ioapic, apic_id);



	return apic_id;

}





int __init io_apic_get_version (int ioapic)

{

	union IO_APIC_reg_01	reg_01;

arch/x86_64/kernel/mpparse.c

+1 −1
Original line number Diff line number Diff line
@@ -759,7 +759,7 @@ void __init mp_register_ioapic ( 
	mp_ioapics[idx].mpc_apicaddr = address;



	set_fixmap_nocache(FIX_IO_APIC_BASE_0 + idx, address);

	mp_ioapics[idx].mpc_apicid = io_apic_get_unique_id(idx, id);

	mp_ioapics[idx].mpc_apicid = id;

	mp_ioapics[idx].mpc_apicver = io_apic_get_version(idx);

	

	/*

include/asm-x86_64/io_apic.h

+0 −1
Original line number Diff line number Diff line
@@ -202,7 +202,6 @@ extern int skip_ioapic_setup; 
#define io_apic_assign_pci_irqs (mp_irq_entries && !skip_ioapic_setup && io_apic_irqs)



#ifdef CONFIG_ACPI_BOOT

extern int io_apic_get_unique_id (int ioapic, int apic_id);

extern int io_apic_get_version (int ioapic);

extern int io_apic_get_redir_entries (int ioapic);

extern int io_apic_set_pci_routing (int ioapic, int pin, int irq, int, int);