Commit c88ac1df authored by Maciej W. Rozycki's avatar Maciej W. Rozycki Committed by Ingo Molnar
Browse files

x86: L-APIC: Always fully configure IRQ0 



Unlike the 32-bit one, the 64-bit variation of the LVT0 setup code for
the "8259A Virtual Wire" through the local APIC timer configuration does
not fully configure the relevant irq_chip structure.  Instead it relies on
the preceding I/O APIC code to have set it up, which does not happen if
the I/O APIC variants have not been tried.

The patch includes corresponding changes to the 32-bit variation too
which make them both the same, barring a small syntactic difference
involving sequence of functions in the source.  That should work as an aid
with the upcoming merge.

Signed-off-by: default avatarMaciej W. Rozycki <macro@linux-mips.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 1baea6e2

arch/x86/kernel/io_apic_32.c

+11 −4
Original line number Diff line number Diff line
@@ -2027,7 +2027,7 @@ static inline void init_IO_APIC_traps(void) 
 * The local APIC irq-chip implementation:

 */



static void ack_apic(unsigned int irq)

static void ack_lapic_irq(unsigned int irq)

{

	ack_APIC_irq();

}
@@ -2052,9 +2052,17 @@ static struct irq_chip lapic_chip __read_mostly = { 
	.name		= "local-APIC",

	.mask		= mask_lapic_irq,

	.unmask		= unmask_lapic_irq,

	.ack		= ack_apic,

	.ack		= ack_lapic_irq,

};



static void lapic_register_intr(int irq, int vector)

{

	irq_desc[irq].status &= ~IRQ_LEVEL;

	set_irq_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,

				      "edge");

	set_intr_gate(vector, interrupt[irq]);

}



static void __init setup_nmi(void)

{

	/*
@@ -2257,8 +2265,7 @@ static inline void __init check_timer(void) 


	printk(KERN_INFO "...trying to set up timer as Virtual Wire IRQ...");



	set_irq_chip_and_handler_name(0, &lapic_chip, handle_edge_irq,

				      "edge");

	lapic_register_intr(0, vector);

	apic_write_around(APIC_LVT0, APIC_DM_FIXED | vector);	/* Fixed mode */

	enable_8259A_irq(0);

arch/x86/kernel/io_apic_64.c

+15 −14
Original line number Diff line number Diff line
@@ -1561,7 +1561,7 @@ static inline void init_IO_APIC_traps(void) 
	}

}



static void enable_lapic_irq (unsigned int irq)

static void unmask_lapic_irq(unsigned int irq)

{

	unsigned long v;
@@ -1569,7 +1569,7 @@ static void enable_lapic_irq (unsigned int irq) 
	apic_write(APIC_LVT0, v & ~APIC_LVT_MASKED);

}



static void disable_lapic_irq (unsigned int irq)

static void mask_lapic_irq(unsigned int irq)

{

	unsigned long v;
@@ -1582,19 +1582,20 @@ static void ack_lapic_irq (unsigned int irq) 
	ack_APIC_irq();

}



static void end_lapic_irq (unsigned int i) { /* nothing */ }



static struct hw_interrupt_type lapic_irq_type __read_mostly = {

static struct irq_chip lapic_chip __read_mostly = {

	.name		= "local-APIC",

	.typename = "local-APIC-edge",

	.startup = NULL, /* startup_irq() not used for IRQ0 */

	.shutdown = NULL, /* shutdown_irq() not used for IRQ0 */

	.enable = enable_lapic_irq,

	.disable = disable_lapic_irq,

	.mask		= mask_lapic_irq,

	.unmask		= unmask_lapic_irq,

	.ack		= ack_lapic_irq,

	.end = end_lapic_irq,

};



static void lapic_register_intr(int irq)

{

	irq_desc[irq].status &= ~IRQ_LEVEL;

	set_irq_chip_and_handler_name(irq, &lapic_chip, handle_edge_irq,

				      "edge");

}



static void __init setup_nmi(void)

{

	/*
@@ -1784,7 +1785,7 @@ static inline void __init check_timer(void) 


	apic_printk(APIC_VERBOSE, KERN_INFO "...trying to set up timer as Virtual Wire IRQ...");



	irq_desc[0].chip = &lapic_irq_type;

	lapic_register_intr(0);

	apic_write(APIC_LVT0, APIC_DM_FIXED | cfg->vector);	/* Fixed mode */

	enable_8259A_irq(0);

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