Commit eddfb4ed authored by Andi Kleen's avatar Andi Kleen Committed by Linus Torvalds
Browse files

[PATCH] x86-64: Remove obsolete APIC "write around" bug workaround 



No x86-64 chipset has this bug

Generated code doesn't change because it was always disabled.

Signed-off-by: default avatarAndi Kleen <ak@suse.de>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent c1507eb2

arch/x86_64/kernel/genapic_cluster.c

+2 −2
Original line number Diff line number Diff line
@@ -51,10 +51,10 @@ static void cluster_init_apic_ldr(void) 
		count = 3;

	id = my_cluster | (1UL << count);

	x86_cpu_to_log_apicid[smp_processor_id()] = id;

	apic_write_around(APIC_DFR, APIC_DFR_CLUSTER);

	apic_write(APIC_DFR, APIC_DFR_CLUSTER);

	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;

	val |= SET_APIC_LOGICAL_ID(id);

	apic_write_around(APIC_LDR, val);

	apic_write(APIC_LDR, val);

}



/* Start with all IRQs pointing to boot CPU.  IRQ balancing will shift them. */

arch/x86_64/kernel/genapic_flat.c

+4 −4
Original line number Diff line number Diff line
@@ -38,10 +38,10 @@ static void flat_init_apic_ldr(void) 
	num = smp_processor_id();

	id = 1UL << num;

	x86_cpu_to_log_apicid[num] = id;

	apic_write_around(APIC_DFR, APIC_DFR_FLAT);

	apic_write(APIC_DFR, APIC_DFR_FLAT);

	val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;

	val |= SET_APIC_LOGICAL_ID(id);

	apic_write_around(APIC_LDR, val);

	apic_write(APIC_LDR, val);

}



static void flat_send_IPI_mask(cpumask_t cpumask, int vector)
@@ -62,7 +62,7 @@ static void flat_send_IPI_mask(cpumask_t cpumask, int vector) 
	 * prepare target chip field

	 */

	cfg = __prepare_ICR2(mask);

	apic_write_around(APIC_ICR2, cfg);

	apic_write(APIC_ICR2, cfg);



	/*

	 * program the ICR
@@ -72,7 +72,7 @@ static void flat_send_IPI_mask(cpumask_t cpumask, int vector) 
	/*

	 * Send the IPI. The write to APIC_ICR fires this off.

	 */

	apic_write_around(APIC_ICR, cfg);

	apic_write(APIC_ICR, cfg);

	local_irq_restore(flags);

}

include/asm-x86_64/ipi.h

+3 −3
Original line number Diff line number Diff line
@@ -66,7 +66,7 @@ static inline void __send_IPI_shortcut(unsigned int shortcut, int vector, unsign 
	/*

	 * Send the IPI. The write to APIC_ICR fires this off.

	 */

	apic_write_around(APIC_ICR, cfg);

	apic_write(APIC_ICR, cfg);

}
@@ -92,7 +92,7 @@ static inline void send_IPI_mask_sequence(cpumask_t mask, int vector) 
		 * prepare target chip field

		 */

		cfg = __prepare_ICR2(x86_cpu_to_apicid[query_cpu]);

		apic_write_around(APIC_ICR2, cfg);

		apic_write(APIC_ICR2, cfg);



		/*

		 * program the ICR
@@ -102,7 +102,7 @@ static inline void send_IPI_mask_sequence(cpumask_t mask, int vector) 
		/*

		 * Send the IPI. The write to APIC_ICR fires this off.

		 */

		apic_write_around(APIC_ICR, cfg);

		apic_write(APIC_ICR, cfg);

	}

	local_irq_restore(flags);

}