iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86, acpi/irq: Introduce apci_isa_irq_to_gsi

Browse Source 
There are a number of cases where the current code makes the assumption
that isa irqs identity map to the first 16 acpi global system intereupts.
In most instances that assumption is correct as that is the required
behaviour in dual i8259 mode and the default behavior in ioapic mode.

However there are some systems out there that take advantage of acpis
interrupt remapping  for the isa irqs to have a completely different
mapping of isa_irq to gsi.

Introduce acpi_isa_irq_to_gsi to perform this mapping explicitly in the
code that needs it.  Initially this will be just the current assumed
identity mapping to ensure it's introduction does not cause regressions.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
LKML-Reference: <1269936436-7039-1-git-send-email-ebiederm@xmission.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
Eric W. Biederman 2010-03-30 01:07:02 -07:00 committed by H. Peter Anvin
parent d93ac51c7a
commit 2c2df8418a
3 changed files with 17 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
arch/ia64/kernel/acpi.c
View File

@ -785,6 +785,14 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
return 0;
}
int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi)
{
if (isa_irq >= 16)
return -1;
*gsi = isa_irq;
return 0;
}
/*
* ACPI based hotplug CPU support
*/

8
arch/x86/kernel/acpi/boot.c
View File

@ -458,6 +458,14 @@ int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
return 0;
}
int acpi_isa_irq_to_gsi(unsigned isa_irq, u32 *gsi)
{
if (isa_irq >= 16)
return -1;
*gsi = isa_irq;
return 0;
}
/*
* success: return IRQ number (>=0)
* failure: return < 0

1
include/linux/acpi.h
View File

@ -116,6 +116,7 @@ extern unsigned long acpi_realmode_flags;
int acpi_register_gsi (struct device *dev, u32 gsi, int triggering, int polarity);
int acpi_gsi_to_irq (u32 gsi, unsigned int *irq);
int acpi_isa_irq_to_gsi (unsigned isa_irq, u32 *gsi);
#ifdef CONFIG_X86_IO_APIC
extern int acpi_get_override_irq(int bus_irq, int *trigger, int *polarity);