Re: [ACPI] [PATCH] Updated patches for PCI IRQ resource deallocation support [2/3]

Kenji Kaneshige
2004-09-24T08:18:28Z

Len,

I've updated ACPI portion of PCI IRQ resource deallocation patch
again based on the feedback from Takayoshi Kochi. Please apply
the following patch instead of the patch I sent before.

Thanks,
Kenji Kaneshige

----
Change Log:

- Changed acpi_pci_irq_disable() to leave 'dev->irq' as it
is. Clearing 'dev->irq' by some magic constant
(e.g. PCI_UNDEFINED_IRQ) is TBD.

Change Log:

- Fixed some typos in comments.

- Changed 'unsigned char irq_disabled' to 'unsigned int
irq_disabled' because pci_dev.irq is unsigned int.

----
Name: IRQ_deallocation_acpi.patch
Kernel Version: 2.6.9-rc2-mm1
Depends: none
Description:

This patch is ACPI portion of IRQ deallocation. This patch defines the
following new interface. The implementation of this interface depends
on each platform.

o void acpi_unregister_gsi(int irq)

This is a opposite portion of acpi_register_gsi(). This has a
responsibility for deallocating IRQ resources associated with
the specified linux IRQ number.

We need to consider the case of shared interrupt. In the case
of shared interrupt, acpi_register_gsi() is called multiple
times for one gsi. That is, registrations and unregistrations
can be nested.

This function undoes the effect of one call to
acpi_register_gsi(). If this matches the last registration,
IRQ resources associated with the specified linux IRQ number
are freed.

This patch also adds the following new function.

o void acpi_pci_irq_disable (struct pci_dev *dev)

This function is a opposite portion of
acpi_pci_enable_irq(). It clears the device's linux IRQ number
and calls acpi_unregister_gsi() to deallocate IRQ resources.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>

---

linux-2.6.9-rc2-mm1-kanesige/arch/i386/kernel/acpi/boot.c | 11 ++++++++
linux-2.6.9-rc2-mm1-kanesige/arch/ia64/kernel/acpi.c | 11 ++++++++
linux-2.6.9-rc2-mm1-kanesige/drivers/acpi/pci_irq.c | 19 ++++++++++++++
linux-2.6.9-rc2-mm1-kanesige/include/linux/acpi.h | 2 +
4 files changed, 43 insertions(+)

diff -puN arch/i386/kernel/acpi/boot.c~IRQ_deallocation_acpi arch/i386/kernel/acpi/boot.c
--- linux-2.6.9-rc2-mm1/arch/i386/kernel/acpi/boot.c~IRQ_deallocation_acpi 2004-09-22 20:29:23.000000000 +0900
+++ linux-2.6.9-rc2-mm1-kanesige/arch/i386/kernel/acpi/boot.c 2004-09-22 20:30:41.000000000 +0900
@@ -480,6 +480,17 @@ unsigned int acpi_register_gsi(u32 gsi,
}
EXPORT_SYMBOL(acpi_register_gsi);

+/*
+ * This function undoes the effect of one call to acpi_register_gsi().
+ * If this matches the last registration, any IRQ resources for gsi
+ * associated with the irq are freed.
+ */
+void
+acpi_unregister_gsi (unsigned int irq)
+{
+}
+EXPORT_SYMBOL(acpi_unregister_gsi);
+
static unsigned long __init
acpi_scan_rsdp (
unsigned long start,
diff -puN arch/ia64/kernel/acpi.c~IRQ_deallocation_acpi arch/ia64/kernel/acpi.c
--- linux-2.6.9-rc2-mm1/arch/ia64/kernel/acpi.c~IRQ_deallocation_acpi 2004-09-22 20:29:23.000000000 +0900
+++ linux-2.6.9-rc2-mm1-kanesige/arch/ia64/kernel/acpi.c 2004-09-24 15:33:01.254399900 +0900
@@ -516,6 +516,17 @@ acpi_register_gsi (u32 gsi, int edge_lev
}
EXPORT_SYMBOL(acpi_register_gsi);

+/*
+ * This function undoes the effect of one call to acpi_register_gsi().
+ * If this matches the last registration, any IRQ resources for gsi
+ * associated with the irq are freed.
+ */
+void
+acpi_unregister_gsi (unsigned int irq)
+{
+}
+EXPORT_SYMBOL(acpi_unregister_gsi);
+
static int __init
acpi_parse_fadt (unsigned long phys_addr, unsigned long size)
{
diff -puN drivers/acpi/pci_irq.c~IRQ_deallocation_acpi drivers/acpi/pci_irq.c
--- linux-2.6.9-rc2-mm1/drivers/acpi/pci_irq.c~IRQ_deallocation_acpi 2004-09-22 20:29:23.000000000 +0900
+++ linux-2.6.9-rc2-mm1-kanesige/drivers/acpi/pci_irq.c 2004-09-24 15:46:01.666952803 +0900
@@ -390,3 +390,22 @@ acpi_pci_irq_enable (

return_VALUE(dev->irq);
}
+
+void
+acpi_pci_irq_disable (
+ struct pci_dev *dev)
+{
+ ACPI_FUNCTION_TRACE("acpi_pci_irq_disable");
+
+ /*
+ * TBD: It might be worth clearing dev->irq by magic constant
+ * (e.g. PCI_UNDEFINED_IRQ).
+ */
+
+ printk(KERN_INFO PREFIX "PCI interrupt for device %s disabled\n",
+ pci_name(dev));
+
+ acpi_unregister_gsi(dev->irq);
+
+ return_VOID;
+}
diff -puN include/linux/acpi.h~IRQ_deallocation_acpi include/linux/acpi.h
--- linux-2.6.9-rc2-mm1/include/linux/acpi.h~IRQ_deallocation_acpi 2004-09-22 20:29:23.000000000 +0900
+++ linux-2.6.9-rc2-mm1-kanesige/include/linux/acpi.h 2004-09-22 20:29:23.000000000 +0900
@@ -414,6 +414,7 @@ static inline int acpi_boot_init(void)
#endif /*!CONFIG_ACPI_BOOT*/

unsigned int acpi_register_gsi (u32 gsi, int edge_level, int active_high_low);
+void acpi_unregister_gsi (unsigned int);
int acpi_gsi_to_irq (u32 gsi, unsigned int *irq);

#ifdef CONFIG_ACPI_PCI
@@ -439,6 +440,7 @@ extern struct acpi_prt_list acpi_prt;
struct pci_dev;

int acpi_pci_irq_enable (struct pci_dev *dev);
+void acpi_pci_irq_disable (struct pci_dev *dev);

struct acpi_pci_driver {
struct acpi_pci_driver *next;

_