[patch 1/3] pci: store PCI_INTERRUPT_PIN in pci_dev

[patch 1/3] pci: store PCI_INTERRUPT_PIN in pci_dev

[Kristen Accardi]

plain text document attachment (patch-interrupt-pin)
Store the value of the INTERRUPT_PIN in the pci_dev structure
so that it can be retrieved later.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
 
 drivers/pci/probe.c |    1 +
 include/linux/pci.h |    1 +
 2 files changed, 2 insertions(+)

Index: linux-2.6.13/drivers/pci/probe.c
===================================================================
--- linux-2.6.13.orig/drivers/pci/probe.c
+++ linux-2.6.13/drivers/pci/probe.c
@@ -571,6 +571,7 @@ static void pci_read_irq(struct pci_dev 
 	unsigned char irq;
 
 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
+	dev->pin = irq;
 	if (irq)
 		pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq);
 	dev->irq = irq;
Index: linux-2.6.13/include/linux/pci.h
===================================================================
--- linux-2.6.13.orig/include/linux/pci.h
+++ linux-2.6.13/include/linux/pci.h
@@ -98,6 +98,7 @@ struct pci_dev {
 	unsigned int	class;		/* 3 bytes: (base,sub,prog-if) */
 	u8		hdr_type;	/* PCI header type (`multi' flag masked out) */
 	u8		rom_base_reg;	/* which config register controls the ROM */
+	u8		pin;  		/* which interrupt pin this device uses */
 
 	struct pci_driver *driver;	/* which driver has allocated this device */
 	u64		dma_mask;	/* Mask of the bits of bus address this

--

Re: [patch 1/3] pci: store PCI_INTERRUPT_PIN in pci_dev

[Rajesh Shah]

On Thu, Oct 27, 2005 at 12:30:09PM -0700, Kristen Accardi wrote:
> --- linux-2.6.13.orig/drivers/pci/probe.c
> +++ linux-2.6.13/drivers/pci/probe.c
> @@ -571,6 +571,7 @@ static void pci_read_irq(struct pci_dev 
>  	unsigned char irq;
>  
>  	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
> +	dev->pin = irq;

pci_read_irq() is not called for PCI bridges, but some of them
may need an interrupt (e.g. for shpchp, pciehp). Did you check
if this patchset broke such bridges? You should call this
function for PCI bridges too.

Rajesh

Re: [patch 1/3] pci: store PCI_INTERRUPT_PIN in pci_dev

[Kristen Accardi]

On Thu, 2005-10-27 at 16:06 -0700, Rajesh Shah wrote:
> On Thu, Oct 27, 2005 at 12:30:09PM -0700, Kristen Accardi wrote:
> > --- linux-2.6.13.orig/drivers/pci/probe.c
> > +++ linux-2.6.13/drivers/pci/probe.c
> > @@ -571,6 +571,7 @@ static void pci_read_irq(struct pci_dev 
> >  	unsigned char irq;
> >  
> >  	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq);
> > +	dev->pin = irq;
> 
> pci_read_irq() is not called for PCI bridges, but some of them
> may need an interrupt (e.g. for shpchp, pciehp). Did you check
> if this patchset broke such bridges? You should call this
> function for PCI bridges too.
> 
> Rajesh
> 

You are correct, this does break for bridges on certain architectures.
Some archs seem to re-read the interrupt pin value in
pcibios_enable_device, but others don't.  Adding pci_read_irq to the
bridge patch in this function does seem to fix the problem, and arch
specific code can still override this.  I'll send a new patch for that.
thanks,
Kristen

[patch 2/3] apci: use stored value of pin from pci_dev

[Kristen Accardi]

plain text document attachment (patch-interrupt-pin-acpi)
Use the stored value of the Interrupt Pin, rather than try to read
it again.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
 
 drivers/acpi/pci_irq.c |    7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

Index: linux-2.6.13/drivers/acpi/pci_irq.c
===================================================================
--- linux-2.6.13.orig/drivers/acpi/pci_irq.c
+++ linux-2.6.13/drivers/acpi/pci_irq.c
@@ -361,8 +361,7 @@ acpi_pci_irq_derive(struct pci_dev *dev,
 
 		if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
 			/* PC card has the same IRQ as its cardbridge */
-			pci_read_config_byte(bridge, PCI_INTERRUPT_PIN,
-					     &bridge_pin);
+			bridge_pin = bridge->pin;
 			if (!bridge_pin) {
 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 						  "No interrupt pin configured for device %s\n",
@@ -412,7 +411,7 @@ int acpi_pci_irq_enable(struct pci_dev *
 	if (!dev)
 		return_VALUE(-EINVAL);
 
-	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+	pin = dev->pin;
 	if (!pin) {
 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 				  "No interrupt pin configured for device %s\n",
@@ -503,7 +502,7 @@ void acpi_pci_irq_disable(struct pci_dev
 	if (!dev || !dev->bus)
 		return_VOID;
 
-	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+	pin = dev->pin;
 	if (!pin)
 		return_VOID;
 	pin--;

--

[patch 3/3] pci: use stored value of pin from pci_dev

[Kristen Accardi]

plain text document attachment (patch-interrupt-pin-pci)
Use the stored value of the interrupt pin rather than try to read
the config again.

Signed-off-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
 
 drivers/pci/pci.c |    2 +-
 1 files changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.13/drivers/pci/pci.c
===================================================================
--- linux-2.6.13.orig/drivers/pci/pci.c
+++ linux-2.6.13/drivers/pci/pci.c
@@ -567,7 +567,7 @@ pci_get_interrupt_pin(struct pci_dev *de
 {
 	u8 pin;
 
-	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+	pin = dev->pin;
 	if (!pin)
 		return -1;
 	pin--;

--