Patchwork ACPI, PCI: Get PRT entry during acpi_pci_enable_irq()

login
register
mail settings
Submitter Yinghai Lu
Date Feb. 12, 2013, 7:11 p.m.
Message ID <1360696283-20313-1-git-send-email-yinghai@kernel.org>
Download mbox | patch
Permalink /patch/219937/
State Accepted
Headers show

Comments

Yinghai Lu - Feb. 12, 2013, 7:11 p.m.
Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has

[    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
[    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5

bisect to
| commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
|     PCI: Put pci_dev in device tree as early as possible

It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
are scanned.

Bjorn said:
 The bus number binding means acpi_pci_irq_add_prt() has to happen
 after enumerating everything below a bridge, and it will prevent us
 from doing any bus number reassignment for hotplug.

 I think we should remove the bus numbers from the cached _PRT (or
 maybe even remove the _PRT caching completely).  When we enable a PCI
 device's IRQ, we should search up the PCI device tree looking for a
 _PRT associated with each node, and applying normal PCI bridge
 swizzling when we don't find a _PRT.  I think this can be done without
 using PCI bus numbers at all.

So here we try to remove _PRT caching completely.

-v2: check !handle early.

Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>

---
 drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
 drivers/acpi/pci_root.c     |   18 --------
 drivers/pci/pci-acpi.c      |   24 -----------
 include/acpi/acpi_drivers.h |    5 --
 4 files changed, 38 insertions(+), 104 deletions(-)

--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Rafael J. Wysocki - Feb. 12, 2013, 8:22 p.m.
On Tuesday, February 12, 2013 11:11:23 AM Yinghai Lu wrote:
> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
> 
> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
> 
> bisect to
> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
> |     PCI: Put pci_dev in device tree as early as possible
> 
> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
> are scanned.
> 
> Bjorn said:
>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>  after enumerating everything below a bridge, and it will prevent us
>  from doing any bus number reassignment for hotplug.
> 
>  I think we should remove the bus numbers from the cached _PRT (or
>  maybe even remove the _PRT caching completely).  When we enable a PCI
>  device's IRQ, we should search up the PCI device tree looking for a
>  _PRT associated with each node, and applying normal PCI bridge
>  swizzling when we don't find a _PRT.  I think this can be done without
>  using PCI bus numbers at all.
> 
> So here we try to remove _PRT caching completely.
> 
> -v2: check !handle early.
> 
> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
> Signed-off-by: Yinghai Lu <yinghai@kernel.org>

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

> ---
>  drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
>  drivers/acpi/pci_root.c     |   18 --------
>  drivers/pci/pci-acpi.c      |   24 -----------
>  include/acpi/acpi_drivers.h |    5 --
>  4 files changed, 38 insertions(+), 104 deletions(-)
> 
> Index: linux-2.6/drivers/acpi/pci_irq.c
> ===================================================================
> --- linux-2.6.orig/drivers/acpi/pci_irq.c
> +++ linux-2.6/drivers/acpi/pci_irq.c
> @@ -53,9 +53,6 @@ struct acpi_prt_entry {
>  	u32			index;		/* GSI, or link _CRS index */
>  };
>  
> -static LIST_HEAD(acpi_prt_list);
> -static DEFINE_SPINLOCK(acpi_prt_lock);
> -
>  static inline char pin_name(int pin)
>  {
>  	return 'A' + pin - 1;
> @@ -65,28 +62,6 @@ static inline char pin_name(int pin)
>                           PCI IRQ Routing Table (PRT) Support
>     -------------------------------------------------------------------------- */
>  
> -static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
> -							  int pin)
> -{
> -	struct acpi_prt_entry *entry;
> -	int segment = pci_domain_nr(dev->bus);
> -	int bus = dev->bus->number;
> -	int device = PCI_SLOT(dev->devfn);
> -
> -	spin_lock(&acpi_prt_lock);
> -	list_for_each_entry(entry, &acpi_prt_list, list) {
> -		if ((segment == entry->id.segment)
> -		    && (bus == entry->id.bus)
> -		    && (device == entry->id.device)
> -		    && (pin == entry->pin)) {
> -			spin_unlock(&acpi_prt_lock);
> -			return entry;
> -		}
> -	}
> -	spin_unlock(&acpi_prt_lock);
> -	return NULL;
> -}
> -
>  /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
>  static const struct dmi_system_id medion_md9580[] = {
>  	{
> @@ -184,11 +159,19 @@ static void do_prt_fixups(struct acpi_pr
>  	}
>  }
>  
> -static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
> -				  struct acpi_pci_routing_table *prt)
> +static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
> +				  int pin, struct acpi_pci_routing_table *prt,
> +				  struct acpi_prt_entry **entry_ptr)
>  {
> +	int segment = pci_domain_nr(dev->bus);
> +	int bus = dev->bus->number;
> +	int device = PCI_SLOT(dev->devfn);
>  	struct acpi_prt_entry *entry;
>  
> +	if (((prt->address >> 16) & 0xffff) != device ||
> +	    prt->pin + 1 != pin)
> +		return -ENODEV;
> +
>  	entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
>  	if (!entry)
>  		return -ENOMEM;
> @@ -237,26 +220,33 @@ static int acpi_pci_irq_add_entry(acpi_h
>  			      entry->id.device, pin_name(entry->pin),
>  			      prt->source, entry->index));
>  
> -	spin_lock(&acpi_prt_lock);
> -	list_add_tail(&entry->list, &acpi_prt_list);
> -	spin_unlock(&acpi_prt_lock);
> +	*entry_ptr = entry;
>  
>  	return 0;
>  }
>  
> -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
> +static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
> +			  int pin, struct acpi_prt_entry **entry_ptr)
>  {
>  	acpi_status status;
>  	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
>  	struct acpi_pci_routing_table *entry;
> +	acpi_handle handle = NULL;
> +
> +	if (dev->bus->bridge)
> +		handle = ACPI_HANDLE(dev->bus->bridge);
> +
> +	if (!handle)
> +		return -ENODEV;
>  
>  	/* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
>  	status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
>  	if (ACPI_FAILURE(status))
>  		return -ENODEV;
>  
> -	printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
> -	       (char *) buffer.pointer);
> +	dev_printk(KERN_DEBUG, &dev->dev,
> +			"ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
> +		       (char *) buffer.pointer);
>  
>  	kfree(buffer.pointer);
>  
> @@ -273,7 +263,9 @@ int acpi_pci_irq_add_prt(acpi_handle han
>  
>  	entry = buffer.pointer;
>  	while (entry && (entry->length > 0)) {
> -		acpi_pci_irq_add_entry(handle, segment, bus, entry);
> +		if (!acpi_pci_irq_check_entry(handle, dev, pin,
> +						 entry, entry_ptr))
> +			break;
>  		entry = (struct acpi_pci_routing_table *)
>  		    ((unsigned long)entry + entry->length);
>  	}
> @@ -282,23 +274,6 @@ int acpi_pci_irq_add_prt(acpi_handle han
>  	return 0;
>  }
>  
> -void acpi_pci_irq_del_prt(int segment, int bus)
> -{
> -	struct acpi_prt_entry *entry, *tmp;
> -
> -	printk(KERN_DEBUG
> -	       "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
> -	       segment, bus);
> -	spin_lock(&acpi_prt_lock);
> -	list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
> -		if (segment == entry->id.segment && bus == entry->id.bus) {
> -			list_del(&entry->list);
> -			kfree(entry);
> -		}
> -	}
> -	spin_unlock(&acpi_prt_lock);
> -}
> -
>  /* --------------------------------------------------------------------------
>                            PCI Interrupt Routing Support
>     -------------------------------------------------------------------------- */
> @@ -359,12 +334,13 @@ static int acpi_reroute_boot_interrupt(s
>  
>  static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
>  {
> -	struct acpi_prt_entry *entry;
> +	struct acpi_prt_entry *entry = NULL;
>  	struct pci_dev *bridge;
>  	u8 bridge_pin, orig_pin = pin;
> +	int ret;
>  
> -	entry = acpi_pci_irq_find_prt_entry(dev, pin);
> -	if (entry) {
> +	ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
> +	if (!ret && entry) {
>  #ifdef CONFIG_X86_IO_APIC
>  		acpi_reroute_boot_interrupt(dev, entry);
>  #endif /* CONFIG_X86_IO_APIC */
> @@ -373,7 +349,7 @@ static struct acpi_prt_entry *acpi_pci_i
>  		return entry;
>  	}
>  
> -	/* 
> +	/*
>  	 * Attempt to derive an IRQ for this device from a parent bridge's
>  	 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
>  	 */
> @@ -393,8 +369,8 @@ static struct acpi_prt_entry *acpi_pci_i
>  			pin = bridge_pin;
>  		}
>  
> -		entry = acpi_pci_irq_find_prt_entry(bridge, pin);
> -		if (entry) {
> +		ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
> +		if (!ret && entry) {
>  			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
>  					 "Derived GSI for %s INT %c from %s\n",
>  					 pci_name(dev), pin_name(orig_pin),
> @@ -470,6 +446,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>  			dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
>  				 pin_name(pin));
>  		}
> +
>  		return 0;
>  	}
>  
> @@ -477,6 +454,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>  	if (rc < 0) {
>  		dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
>  			 pin_name(pin));
> +		kfree(entry);
>  		return rc;
>  	}
>  	dev->irq = rc;
> @@ -491,6 +469,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>  		(triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
>  		(polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
>  
> +	kfree(entry);
>  	return 0;
>  }
>  
> @@ -513,6 +492,8 @@ void acpi_pci_irq_disable(struct pci_dev
>  	else
>  		gsi = entry->index;
>  
> +	kfree(entry);
> +
>  	/*
>  	 * TBD: It might be worth clearing dev->irq by magic constant
>  	 * (e.g. PCI_UNDEFINED_IRQ).
> Index: linux-2.6/drivers/acpi/pci_root.c
> ===================================================================
> --- linux-2.6.orig/drivers/acpi/pci_root.c
> +++ linux-2.6/drivers/acpi/pci_root.c
> @@ -413,7 +413,6 @@ static int acpi_pci_root_add(struct acpi
>  	acpi_status status;
>  	int result;
>  	struct acpi_pci_root *root;
> -	acpi_handle handle;
>  	struct acpi_pci_driver *driver;
>  	u32 flags, base_flags;
>  	bool is_osc_granted = false;
> @@ -468,16 +467,6 @@ static int acpi_pci_root_add(struct acpi
>  	       acpi_device_name(device), acpi_device_bid(device),
>  	       root->segment, &root->secondary);
>  
> -	/*
> -	 * PCI Routing Table
> -	 * -----------------
> -	 * Evaluate and parse _PRT, if exists.
> -	 */
> -	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
> -	if (ACPI_SUCCESS(status))
> -		result = acpi_pci_irq_add_prt(device->handle, root->segment,
> -					      root->secondary.start);
> -
>  	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
>  
>  	/*
> @@ -602,7 +591,6 @@ out_del_root:
>  	list_del(&root->node);
>  	mutex_unlock(&acpi_pci_root_lock);
>  
> -	acpi_pci_irq_del_prt(root->segment, root->secondary.start);
>  end:
>  	kfree(root);
>  	return result;
> @@ -610,8 +598,6 @@ end:
>  
>  static void acpi_pci_root_remove(struct acpi_device *device)
>  {
> -	acpi_status status;
> -	acpi_handle handle;
>  	struct acpi_pci_root *root = acpi_driver_data(device);
>  	struct acpi_pci_driver *driver;
>  
> @@ -626,10 +612,6 @@ static void acpi_pci_root_remove(struct
>  	device_set_run_wake(root->bus->bridge, false);
>  	pci_acpi_remove_bus_pm_notifier(device);
>  
> -	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
> -	if (ACPI_SUCCESS(status))
> -		acpi_pci_irq_del_prt(root->segment, root->secondary.start);
> -
>  	pci_remove_root_bus(root->bus);
>  
>  	mutex_lock(&acpi_pci_root_lock);
> Index: linux-2.6/drivers/pci/pci-acpi.c
> ===================================================================
> --- linux-2.6.orig/drivers/pci/pci-acpi.c
> +++ linux-2.6/drivers/pci/pci-acpi.c
> @@ -307,25 +307,6 @@ static void pci_acpi_setup(struct device
>  	struct pci_dev *pci_dev = to_pci_dev(dev);
>  	acpi_handle handle = ACPI_HANDLE(dev);
>  	struct acpi_device *adev;
> -	acpi_status status;
> -	acpi_handle dummy;
> -
> -	/*
> -	 * Evaluate and parse _PRT, if exists.  This code allows parsing of
> -	 * _PRT objects within the scope of non-bridge devices.  Note that
> -	 * _PRTs within the scope of a PCI bridge assume the bridge's
> -	 * subordinate bus number.
> -	 *
> -	 * TBD: Can _PRTs exist within the scope of non-bridge PCI devices?
> -	 */
> -	status = acpi_get_handle(handle, METHOD_NAME__PRT, &dummy);
> -	if (ACPI_SUCCESS(status)) {
> -		unsigned char bus;
> -
> -		bus = pci_dev->subordinate ?
> -			pci_dev->subordinate->number : pci_dev->bus->number;
> -		acpi_pci_irq_add_prt(handle, pci_domain_nr(pci_dev->bus), bus);
> -	}
>  
>  	if (acpi_bus_get_device(handle, &adev) || !adev->wakeup.flags.valid)
>  		return;
> @@ -340,7 +321,6 @@ static void pci_acpi_setup(struct device
>  
>  static void pci_acpi_cleanup(struct device *dev)
>  {
> -	struct pci_dev *pci_dev = to_pci_dev(dev);
>  	acpi_handle handle = ACPI_HANDLE(dev);
>  	struct acpi_device *adev;
>  
> @@ -349,10 +329,6 @@ static void pci_acpi_cleanup(struct devi
>  		device_set_run_wake(dev, false);
>  		pci_acpi_remove_pm_notifier(adev);
>  	}
> -
> -	if (pci_dev->subordinate)
> -		acpi_pci_irq_del_prt(pci_domain_nr(pci_dev->bus),
> -				     pci_dev->subordinate->number);
>  }
>  
>  static struct acpi_bus_type acpi_pci_bus = {
> Index: linux-2.6/include/acpi/acpi_drivers.h
> ===================================================================
> --- linux-2.6.orig/include/acpi/acpi_drivers.h
> +++ linux-2.6/include/acpi/acpi_drivers.h
> @@ -90,11 +90,6 @@ int acpi_pci_link_allocate_irq(acpi_hand
>  			       int *polarity, char **name);
>  int acpi_pci_link_free_irq(acpi_handle handle);
>  
> -/* ACPI PCI Interrupt Routing (pci_irq.c) */
> -
> -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus);
> -void acpi_pci_irq_del_prt(int segment, int bus);
> -
>  /* ACPI PCI Device Binding (pci_bind.c) */
>  
>  struct pci_bus;
Peter Hurley - Feb. 13, 2013, 2:20 a.m.
On Tue, 2013-02-12 at 11:11 -0800, Yinghai Lu wrote:
> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
> 
> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
> 
> bisect to
> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
> |     PCI: Put pci_dev in device tree as early as possible
> 
> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
> are scanned.
> 
> Bjorn said:
>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>  after enumerating everything below a bridge, and it will prevent us
>  from doing any bus number reassignment for hotplug.
> 
>  I think we should remove the bus numbers from the cached _PRT (or
>  maybe even remove the _PRT caching completely).  When we enable a PCI
>  device's IRQ, we should search up the PCI device tree looking for a
>  _PRT associated with each node, and applying normal PCI bridge
>  swizzling when we don't find a _PRT.  I think this can be done without
>  using PCI bus numbers at all.
> 
> So here we try to remove _PRT caching completely.
> 
> -v2: check !handle early.
> 
> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>

Actually true now :)

Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>

Regards and thanks again,
Peter Hurley

PS - I just happened to see this version on the list. Would you please
cc me on any future versions?


--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Yinghai Lu - Feb. 13, 2013, 2:42 a.m.
On Tue, Feb 12, 2013 at 6:20 PM, Peter Hurley <peter@hurleysoftware.com> wrote:
> On Tue, 2013-02-12 at 11:11 -0800, Yinghai Lu wrote:
>> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
>>
>> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
>> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
>>
>> bisect to
>> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
>> |     PCI: Put pci_dev in device tree as early as possible
>>
>> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
>> are scanned.
>>
>> Bjorn said:
>>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>>  after enumerating everything below a bridge, and it will prevent us
>>  from doing any bus number reassignment for hotplug.
>>
>>  I think we should remove the bus numbers from the cached _PRT (or
>>  maybe even remove the _PRT caching completely).  When we enable a PCI
>>  device's IRQ, we should search up the PCI device tree looking for a
>>  _PRT associated with each node, and applying normal PCI bridge
>>  swizzling when we don't find a _PRT.  I think this can be done without
>>  using PCI bus numbers at all.
>>
>> So here we try to remove _PRT caching completely.
>>
>> -v2: check !handle early.
>>
>> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
>
> Actually true now :)
>
> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>

Thanks.

> PS - I just happened to see this version on the list. Would you please
> cc me on any future versions?

oh, my fault. I take it for granted that "git send-email" will pick
that email from
patch just like Cc.

Yinghai
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Peter Hurley - Feb. 13, 2013, 3:18 a.m.
On Tue, 2013-02-12 at 18:42 -0800, Yinghai Lu wrote:
> On Tue, Feb 12, 2013 at 6:20 PM, Peter Hurley <peter@hurleysoftware.com> wrote:
> >
> > Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
> 
> Thanks.
> 
> > PS - I just happened to see this version on the list. Would you please
> > cc me on any future versions?
> 
> oh, my fault. I take it for granted that "git send-email" will pick
> that email from
> patch just like Cc.

No problem. Actually, I'm sorry it took this long for me to test. I was
stuck in an epic bisect that I eventually abandoned at the 41st test
with it still in merge bases.


--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Yinghai Lu - Feb. 15, 2013, 12:50 a.m.
On Tue, Feb 12, 2013 at 12:22 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
> On Tuesday, February 12, 2013 11:11:23 AM Yinghai Lu wrote:
>> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
>>
>> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
>> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
>>
>> bisect to
>> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
>> |     PCI: Put pci_dev in device tree as early as possible
>>
>> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
>> are scanned.
>>
>> Bjorn said:
>>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>>  after enumerating everything below a bridge, and it will prevent us
>>  from doing any bus number reassignment for hotplug.
>>
>>  I think we should remove the bus numbers from the cached _PRT (or
>>  maybe even remove the _PRT caching completely).  When we enable a PCI
>>  device's IRQ, we should search up the PCI device tree looking for a
>>  _PRT associated with each node, and applying normal PCI bridge
>>  swizzling when we don't find a _PRT.  I think this can be done without
>>  using PCI bus numbers at all.
>>
>> So here we try to remove _PRT caching completely.
>>
>> -v2: check !handle early.
>>
>> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
>
> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>
>> ---
>>  drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
>>  drivers/acpi/pci_root.c     |   18 --------
>>  drivers/pci/pci-acpi.c      |   24 -----------
>>  include/acpi/acpi_drivers.h |    5 --
>>  4 files changed, 38 insertions(+), 104 deletions(-)

Bjorn,

Can you put this one into pci/next?

Thanks

Yinghai

>>
>> Index: linux-2.6/drivers/acpi/pci_irq.c
>> ===================================================================
>> --- linux-2.6.orig/drivers/acpi/pci_irq.c
>> +++ linux-2.6/drivers/acpi/pci_irq.c
>> @@ -53,9 +53,6 @@ struct acpi_prt_entry {
>>       u32                     index;          /* GSI, or link _CRS index */
>>  };
>>
>> -static LIST_HEAD(acpi_prt_list);
>> -static DEFINE_SPINLOCK(acpi_prt_lock);
>> -
>>  static inline char pin_name(int pin)
>>  {
>>       return 'A' + pin - 1;
>> @@ -65,28 +62,6 @@ static inline char pin_name(int pin)
>>                           PCI IRQ Routing Table (PRT) Support
>>     -------------------------------------------------------------------------- */
>>
>> -static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
>> -                                                       int pin)
>> -{
>> -     struct acpi_prt_entry *entry;
>> -     int segment = pci_domain_nr(dev->bus);
>> -     int bus = dev->bus->number;
>> -     int device = PCI_SLOT(dev->devfn);
>> -
>> -     spin_lock(&acpi_prt_lock);
>> -     list_for_each_entry(entry, &acpi_prt_list, list) {
>> -             if ((segment == entry->id.segment)
>> -                 && (bus == entry->id.bus)
>> -                 && (device == entry->id.device)
>> -                 && (pin == entry->pin)) {
>> -                     spin_unlock(&acpi_prt_lock);
>> -                     return entry;
>> -             }
>> -     }
>> -     spin_unlock(&acpi_prt_lock);
>> -     return NULL;
>> -}
>> -
>>  /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
>>  static const struct dmi_system_id medion_md9580[] = {
>>       {
>> @@ -184,11 +159,19 @@ static void do_prt_fixups(struct acpi_pr
>>       }
>>  }
>>
>> -static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
>> -                               struct acpi_pci_routing_table *prt)
>> +static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
>> +                               int pin, struct acpi_pci_routing_table *prt,
>> +                               struct acpi_prt_entry **entry_ptr)
>>  {
>> +     int segment = pci_domain_nr(dev->bus);
>> +     int bus = dev->bus->number;
>> +     int device = PCI_SLOT(dev->devfn);
>>       struct acpi_prt_entry *entry;
>>
>> +     if (((prt->address >> 16) & 0xffff) != device ||
>> +         prt->pin + 1 != pin)
>> +             return -ENODEV;
>> +
>>       entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
>>       if (!entry)
>>               return -ENOMEM;
>> @@ -237,26 +220,33 @@ static int acpi_pci_irq_add_entry(acpi_h
>>                             entry->id.device, pin_name(entry->pin),
>>                             prt->source, entry->index));
>>
>> -     spin_lock(&acpi_prt_lock);
>> -     list_add_tail(&entry->list, &acpi_prt_list);
>> -     spin_unlock(&acpi_prt_lock);
>> +     *entry_ptr = entry;
>>
>>       return 0;
>>  }
>>
>> -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
>> +static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
>> +                       int pin, struct acpi_prt_entry **entry_ptr)
>>  {
>>       acpi_status status;
>>       struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
>>       struct acpi_pci_routing_table *entry;
>> +     acpi_handle handle = NULL;
>> +
>> +     if (dev->bus->bridge)
>> +             handle = ACPI_HANDLE(dev->bus->bridge);
>> +
>> +     if (!handle)
>> +             return -ENODEV;
>>
>>       /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
>>       status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
>>       if (ACPI_FAILURE(status))
>>               return -ENODEV;
>>
>> -     printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
>> -            (char *) buffer.pointer);
>> +     dev_printk(KERN_DEBUG, &dev->dev,
>> +                     "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
>> +                    (char *) buffer.pointer);
>>
>>       kfree(buffer.pointer);
>>
>> @@ -273,7 +263,9 @@ int acpi_pci_irq_add_prt(acpi_handle han
>>
>>       entry = buffer.pointer;
>>       while (entry && (entry->length > 0)) {
>> -             acpi_pci_irq_add_entry(handle, segment, bus, entry);
>> +             if (!acpi_pci_irq_check_entry(handle, dev, pin,
>> +                                              entry, entry_ptr))
>> +                     break;
>>               entry = (struct acpi_pci_routing_table *)
>>                   ((unsigned long)entry + entry->length);
>>       }
>> @@ -282,23 +274,6 @@ int acpi_pci_irq_add_prt(acpi_handle han
>>       return 0;
>>  }
>>
>> -void acpi_pci_irq_del_prt(int segment, int bus)
>> -{
>> -     struct acpi_prt_entry *entry, *tmp;
>> -
>> -     printk(KERN_DEBUG
>> -            "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
>> -            segment, bus);
>> -     spin_lock(&acpi_prt_lock);
>> -     list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
>> -             if (segment == entry->id.segment && bus == entry->id.bus) {
>> -                     list_del(&entry->list);
>> -                     kfree(entry);
>> -             }
>> -     }
>> -     spin_unlock(&acpi_prt_lock);
>> -}
>> -
>>  /* --------------------------------------------------------------------------
>>                            PCI Interrupt Routing Support
>>     -------------------------------------------------------------------------- */
>> @@ -359,12 +334,13 @@ static int acpi_reroute_boot_interrupt(s
>>
>>  static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
>>  {
>> -     struct acpi_prt_entry *entry;
>> +     struct acpi_prt_entry *entry = NULL;
>>       struct pci_dev *bridge;
>>       u8 bridge_pin, orig_pin = pin;
>> +     int ret;
>>
>> -     entry = acpi_pci_irq_find_prt_entry(dev, pin);
>> -     if (entry) {
>> +     ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
>> +     if (!ret && entry) {
>>  #ifdef CONFIG_X86_IO_APIC
>>               acpi_reroute_boot_interrupt(dev, entry);
>>  #endif /* CONFIG_X86_IO_APIC */
>> @@ -373,7 +349,7 @@ static struct acpi_prt_entry *acpi_pci_i
>>               return entry;
>>       }
>>
>> -     /*
>> +     /*
>>        * Attempt to derive an IRQ for this device from a parent bridge's
>>        * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
>>        */
>> @@ -393,8 +369,8 @@ static struct acpi_prt_entry *acpi_pci_i
>>                       pin = bridge_pin;
>>               }
>>
>> -             entry = acpi_pci_irq_find_prt_entry(bridge, pin);
>> -             if (entry) {
>> +             ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
>> +             if (!ret && entry) {
>>                       ACPI_DEBUG_PRINT((ACPI_DB_INFO,
>>                                        "Derived GSI for %s INT %c from %s\n",
>>                                        pci_name(dev), pin_name(orig_pin),
>> @@ -470,6 +446,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>>                       dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
>>                                pin_name(pin));
>>               }
>> +
>>               return 0;
>>       }
>>
>> @@ -477,6 +454,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>>       if (rc < 0) {
>>               dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
>>                        pin_name(pin));
>> +             kfree(entry);
>>               return rc;
>>       }
>>       dev->irq = rc;
>> @@ -491,6 +469,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>>               (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
>>               (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
>>
>> +     kfree(entry);
>>       return 0;
>>  }
>>
>> @@ -513,6 +492,8 @@ void acpi_pci_irq_disable(struct pci_dev
>>       else
>>               gsi = entry->index;
>>
>> +     kfree(entry);
>> +
>>       /*
>>        * TBD: It might be worth clearing dev->irq by magic constant
>>        * (e.g. PCI_UNDEFINED_IRQ).
>> Index: linux-2.6/drivers/acpi/pci_root.c
>> ===================================================================
>> --- linux-2.6.orig/drivers/acpi/pci_root.c
>> +++ linux-2.6/drivers/acpi/pci_root.c
>> @@ -413,7 +413,6 @@ static int acpi_pci_root_add(struct acpi
>>       acpi_status status;
>>       int result;
>>       struct acpi_pci_root *root;
>> -     acpi_handle handle;
>>       struct acpi_pci_driver *driver;
>>       u32 flags, base_flags;
>>       bool is_osc_granted = false;
>> @@ -468,16 +467,6 @@ static int acpi_pci_root_add(struct acpi
>>              acpi_device_name(device), acpi_device_bid(device),
>>              root->segment, &root->secondary);
>>
>> -     /*
>> -      * PCI Routing Table
>> -      * -----------------
>> -      * Evaluate and parse _PRT, if exists.
>> -      */
>> -     status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
>> -     if (ACPI_SUCCESS(status))
>> -             result = acpi_pci_irq_add_prt(device->handle, root->segment,
>> -                                           root->secondary.start);
>> -
>>       root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
>>
>>       /*
>> @@ -602,7 +591,6 @@ out_del_root:
>>       list_del(&root->node);
>>       mutex_unlock(&acpi_pci_root_lock);
>>
>> -     acpi_pci_irq_del_prt(root->segment, root->secondary.start);
>>  end:
>>       kfree(root);
>>       return result;
>> @@ -610,8 +598,6 @@ end:
>>
>>  static void acpi_pci_root_remove(struct acpi_device *device)
>>  {
>> -     acpi_status status;
>> -     acpi_handle handle;
>>       struct acpi_pci_root *root = acpi_driver_data(device);
>>       struct acpi_pci_driver *driver;
>>
>> @@ -626,10 +612,6 @@ static void acpi_pci_root_remove(struct
>>       device_set_run_wake(root->bus->bridge, false);
>>       pci_acpi_remove_bus_pm_notifier(device);
>>
>> -     status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
>> -     if (ACPI_SUCCESS(status))
>> -             acpi_pci_irq_del_prt(root->segment, root->secondary.start);
>> -
>>       pci_remove_root_bus(root->bus);
>>
>>       mutex_lock(&acpi_pci_root_lock);
>> Index: linux-2.6/drivers/pci/pci-acpi.c
>> ===================================================================
>> --- linux-2.6.orig/drivers/pci/pci-acpi.c
>> +++ linux-2.6/drivers/pci/pci-acpi.c
>> @@ -307,25 +307,6 @@ static void pci_acpi_setup(struct device
>>       struct pci_dev *pci_dev = to_pci_dev(dev);
>>       acpi_handle handle = ACPI_HANDLE(dev);
>>       struct acpi_device *adev;
>> -     acpi_status status;
>> -     acpi_handle dummy;
>> -
>> -     /*
>> -      * Evaluate and parse _PRT, if exists.  This code allows parsing of
>> -      * _PRT objects within the scope of non-bridge devices.  Note that
>> -      * _PRTs within the scope of a PCI bridge assume the bridge's
>> -      * subordinate bus number.
>> -      *
>> -      * TBD: Can _PRTs exist within the scope of non-bridge PCI devices?
>> -      */
>> -     status = acpi_get_handle(handle, METHOD_NAME__PRT, &dummy);
>> -     if (ACPI_SUCCESS(status)) {
>> -             unsigned char bus;
>> -
>> -             bus = pci_dev->subordinate ?
>> -                     pci_dev->subordinate->number : pci_dev->bus->number;
>> -             acpi_pci_irq_add_prt(handle, pci_domain_nr(pci_dev->bus), bus);
>> -     }
>>
>>       if (acpi_bus_get_device(handle, &adev) || !adev->wakeup.flags.valid)
>>               return;
>> @@ -340,7 +321,6 @@ static void pci_acpi_setup(struct device
>>
>>  static void pci_acpi_cleanup(struct device *dev)
>>  {
>> -     struct pci_dev *pci_dev = to_pci_dev(dev);
>>       acpi_handle handle = ACPI_HANDLE(dev);
>>       struct acpi_device *adev;
>>
>> @@ -349,10 +329,6 @@ static void pci_acpi_cleanup(struct devi
>>               device_set_run_wake(dev, false);
>>               pci_acpi_remove_pm_notifier(adev);
>>       }
>> -
>> -     if (pci_dev->subordinate)
>> -             acpi_pci_irq_del_prt(pci_domain_nr(pci_dev->bus),
>> -                                  pci_dev->subordinate->number);
>>  }
>>
>>  static struct acpi_bus_type acpi_pci_bus = {
>> Index: linux-2.6/include/acpi/acpi_drivers.h
>> ===================================================================
>> --- linux-2.6.orig/include/acpi/acpi_drivers.h
>> +++ linux-2.6/include/acpi/acpi_drivers.h
>> @@ -90,11 +90,6 @@ int acpi_pci_link_allocate_irq(acpi_hand
>>                              int *polarity, char **name);
>>  int acpi_pci_link_free_irq(acpi_handle handle);
>>
>> -/* ACPI PCI Interrupt Routing (pci_irq.c) */
>> -
>> -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus);
>> -void acpi_pci_irq_del_prt(int segment, int bus);
>> -
>>  /* ACPI PCI Device Binding (pci_bind.c) */
>>
>>  struct pci_bus;
> --
> I speak only for myself.
> Rafael J. Wysocki, Intel Open Source Technology Center.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Bjorn Helgaas - Feb. 16, 2013, 12:39 a.m.
On Thu, Feb 14, 2013 at 5:50 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Tue, Feb 12, 2013 at 12:22 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
>> On Tuesday, February 12, 2013 11:11:23 AM Yinghai Lu wrote:
>>> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
>>>
>>> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
>>> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
>>>
>>> bisect to
>>> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
>>> |     PCI: Put pci_dev in device tree as early as possible
>>>
>>> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
>>> are scanned.
>>>
>>> Bjorn said:
>>>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>>>  after enumerating everything below a bridge, and it will prevent us
>>>  from doing any bus number reassignment for hotplug.
>>>
>>>  I think we should remove the bus numbers from the cached _PRT (or
>>>  maybe even remove the _PRT caching completely).  When we enable a PCI
>>>  device's IRQ, we should search up the PCI device tree looking for a
>>>  _PRT associated with each node, and applying normal PCI bridge
>>>  swizzling when we don't find a _PRT.  I think this can be done without
>>>  using PCI bus numbers at all.
>>>
>>> So here we try to remove _PRT caching completely.
>>>
>>> -v2: check !handle early.
>>>
>>> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
>>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
>>
>> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>
>>> ---
>>>  drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
>>>  drivers/acpi/pci_root.c     |   18 --------
>>>  drivers/pci/pci-acpi.c      |   24 -----------
>>>  include/acpi/acpi_drivers.h |    5 --
>>>  4 files changed, 38 insertions(+), 104 deletions(-)
>
> Bjorn,
>
> Can you put this one into pci/next?

I'm not sure what this patch is based on or what the best way to merge
it is.  It doesn't apply cleanly to my next or
pci/yinghai-root-bus-hotplug branches.

I did apply it manually on top of pci/yinghai-root-bus-hotplug to try
it out, but we need to tweak the messages a little bit.

Previously we printed "ACPI: PCI Interrupt Routing Table [%s._PRT]"
once when loading it, which was fine.  Now we print it every time we
look at a _PRT, which is too much because it isn't really adding any
information.

We also print "ACPI Exception: AE_NOT_FOUND, Evaluating _PRT
[AE_NOT_FOUND] (20121018/pci_irq-259)" if we find ACPI nodes without
_PRTs, which we shouldn't do, because that's a common and normal
situation.

Bjorn

>>> Index: linux-2.6/drivers/acpi/pci_irq.c
>>> ===================================================================
>>> --- linux-2.6.orig/drivers/acpi/pci_irq.c
>>> +++ linux-2.6/drivers/acpi/pci_irq.c
>>> @@ -53,9 +53,6 @@ struct acpi_prt_entry {
>>>       u32                     index;          /* GSI, or link _CRS index */
>>>  };
>>>
>>> -static LIST_HEAD(acpi_prt_list);
>>> -static DEFINE_SPINLOCK(acpi_prt_lock);
>>> -
>>>  static inline char pin_name(int pin)
>>>  {
>>>       return 'A' + pin - 1;
>>> @@ -65,28 +62,6 @@ static inline char pin_name(int pin)
>>>                           PCI IRQ Routing Table (PRT) Support
>>>     -------------------------------------------------------------------------- */
>>>
>>> -static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
>>> -                                                       int pin)
>>> -{
>>> -     struct acpi_prt_entry *entry;
>>> -     int segment = pci_domain_nr(dev->bus);
>>> -     int bus = dev->bus->number;
>>> -     int device = PCI_SLOT(dev->devfn);
>>> -
>>> -     spin_lock(&acpi_prt_lock);
>>> -     list_for_each_entry(entry, &acpi_prt_list, list) {
>>> -             if ((segment == entry->id.segment)
>>> -                 && (bus == entry->id.bus)
>>> -                 && (device == entry->id.device)
>>> -                 && (pin == entry->pin)) {
>>> -                     spin_unlock(&acpi_prt_lock);
>>> -                     return entry;
>>> -             }
>>> -     }
>>> -     spin_unlock(&acpi_prt_lock);
>>> -     return NULL;
>>> -}
>>> -
>>>  /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
>>>  static const struct dmi_system_id medion_md9580[] = {
>>>       {
>>> @@ -184,11 +159,19 @@ static void do_prt_fixups(struct acpi_pr
>>>       }
>>>  }
>>>
>>> -static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
>>> -                               struct acpi_pci_routing_table *prt)
>>> +static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
>>> +                               int pin, struct acpi_pci_routing_table *prt,
>>> +                               struct acpi_prt_entry **entry_ptr)
>>>  {
>>> +     int segment = pci_domain_nr(dev->bus);
>>> +     int bus = dev->bus->number;
>>> +     int device = PCI_SLOT(dev->devfn);
>>>       struct acpi_prt_entry *entry;
>>>
>>> +     if (((prt->address >> 16) & 0xffff) != device ||
>>> +         prt->pin + 1 != pin)
>>> +             return -ENODEV;
>>> +
>>>       entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
>>>       if (!entry)
>>>               return -ENOMEM;
>>> @@ -237,26 +220,33 @@ static int acpi_pci_irq_add_entry(acpi_h
>>>                             entry->id.device, pin_name(entry->pin),
>>>                             prt->source, entry->index));
>>>
>>> -     spin_lock(&acpi_prt_lock);
>>> -     list_add_tail(&entry->list, &acpi_prt_list);
>>> -     spin_unlock(&acpi_prt_lock);
>>> +     *entry_ptr = entry;
>>>
>>>       return 0;
>>>  }
>>>
>>> -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
>>> +static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
>>> +                       int pin, struct acpi_prt_entry **entry_ptr)
>>>  {
>>>       acpi_status status;
>>>       struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
>>>       struct acpi_pci_routing_table *entry;
>>> +     acpi_handle handle = NULL;
>>> +
>>> +     if (dev->bus->bridge)
>>> +             handle = ACPI_HANDLE(dev->bus->bridge);
>>> +
>>> +     if (!handle)
>>> +             return -ENODEV;
>>>
>>>       /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
>>>       status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
>>>       if (ACPI_FAILURE(status))
>>>               return -ENODEV;
>>>
>>> -     printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
>>> -            (char *) buffer.pointer);
>>> +     dev_printk(KERN_DEBUG, &dev->dev,
>>> +                     "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
>>> +                    (char *) buffer.pointer);
>>>
>>>       kfree(buffer.pointer);
>>>
>>> @@ -273,7 +263,9 @@ int acpi_pci_irq_add_prt(acpi_handle han
>>>
>>>       entry = buffer.pointer;
>>>       while (entry && (entry->length > 0)) {
>>> -             acpi_pci_irq_add_entry(handle, segment, bus, entry);
>>> +             if (!acpi_pci_irq_check_entry(handle, dev, pin,
>>> +                                              entry, entry_ptr))
>>> +                     break;
>>>               entry = (struct acpi_pci_routing_table *)
>>>                   ((unsigned long)entry + entry->length);
>>>       }
>>> @@ -282,23 +274,6 @@ int acpi_pci_irq_add_prt(acpi_handle han
>>>       return 0;
>>>  }
>>>
>>> -void acpi_pci_irq_del_prt(int segment, int bus)
>>> -{
>>> -     struct acpi_prt_entry *entry, *tmp;
>>> -
>>> -     printk(KERN_DEBUG
>>> -            "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
>>> -            segment, bus);
>>> -     spin_lock(&acpi_prt_lock);
>>> -     list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
>>> -             if (segment == entry->id.segment && bus == entry->id.bus) {
>>> -                     list_del(&entry->list);
>>> -                     kfree(entry);
>>> -             }
>>> -     }
>>> -     spin_unlock(&acpi_prt_lock);
>>> -}
>>> -
>>>  /* --------------------------------------------------------------------------
>>>                            PCI Interrupt Routing Support
>>>     -------------------------------------------------------------------------- */
>>> @@ -359,12 +334,13 @@ static int acpi_reroute_boot_interrupt(s
>>>
>>>  static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
>>>  {
>>> -     struct acpi_prt_entry *entry;
>>> +     struct acpi_prt_entry *entry = NULL;
>>>       struct pci_dev *bridge;
>>>       u8 bridge_pin, orig_pin = pin;
>>> +     int ret;
>>>
>>> -     entry = acpi_pci_irq_find_prt_entry(dev, pin);
>>> -     if (entry) {
>>> +     ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
>>> +     if (!ret && entry) {
>>>  #ifdef CONFIG_X86_IO_APIC
>>>               acpi_reroute_boot_interrupt(dev, entry);
>>>  #endif /* CONFIG_X86_IO_APIC */
>>> @@ -373,7 +349,7 @@ static struct acpi_prt_entry *acpi_pci_i
>>>               return entry;
>>>       }
>>>
>>> -     /*
>>> +     /*
>>>        * Attempt to derive an IRQ for this device from a parent bridge's
>>>        * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
>>>        */
>>> @@ -393,8 +369,8 @@ static struct acpi_prt_entry *acpi_pci_i
>>>                       pin = bridge_pin;
>>>               }
>>>
>>> -             entry = acpi_pci_irq_find_prt_entry(bridge, pin);
>>> -             if (entry) {
>>> +             ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
>>> +             if (!ret && entry) {
>>>                       ACPI_DEBUG_PRINT((ACPI_DB_INFO,
>>>                                        "Derived GSI for %s INT %c from %s\n",
>>>                                        pci_name(dev), pin_name(orig_pin),
>>> @@ -470,6 +446,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>>>                       dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
>>>                                pin_name(pin));
>>>               }
>>> +
>>>               return 0;
>>>       }
>>>
>>> @@ -477,6 +454,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>>>       if (rc < 0) {
>>>               dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
>>>                        pin_name(pin));
>>> +             kfree(entry);
>>>               return rc;
>>>       }
>>>       dev->irq = rc;
>>> @@ -491,6 +469,7 @@ int acpi_pci_irq_enable(struct pci_dev *
>>>               (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
>>>               (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
>>>
>>> +     kfree(entry);
>>>       return 0;
>>>  }
>>>
>>> @@ -513,6 +492,8 @@ void acpi_pci_irq_disable(struct pci_dev
>>>       else
>>>               gsi = entry->index;
>>>
>>> +     kfree(entry);
>>> +
>>>       /*
>>>        * TBD: It might be worth clearing dev->irq by magic constant
>>>        * (e.g. PCI_UNDEFINED_IRQ).
>>> Index: linux-2.6/drivers/acpi/pci_root.c
>>> ===================================================================
>>> --- linux-2.6.orig/drivers/acpi/pci_root.c
>>> +++ linux-2.6/drivers/acpi/pci_root.c
>>> @@ -413,7 +413,6 @@ static int acpi_pci_root_add(struct acpi
>>>       acpi_status status;
>>>       int result;
>>>       struct acpi_pci_root *root;
>>> -     acpi_handle handle;
>>>       struct acpi_pci_driver *driver;
>>>       u32 flags, base_flags;
>>>       bool is_osc_granted = false;
>>> @@ -468,16 +467,6 @@ static int acpi_pci_root_add(struct acpi
>>>              acpi_device_name(device), acpi_device_bid(device),
>>>              root->segment, &root->secondary);
>>>
>>> -     /*
>>> -      * PCI Routing Table
>>> -      * -----------------
>>> -      * Evaluate and parse _PRT, if exists.
>>> -      */
>>> -     status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
>>> -     if (ACPI_SUCCESS(status))
>>> -             result = acpi_pci_irq_add_prt(device->handle, root->segment,
>>> -                                           root->secondary.start);
>>> -
>>>       root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
>>>
>>>       /*
>>> @@ -602,7 +591,6 @@ out_del_root:
>>>       list_del(&root->node);
>>>       mutex_unlock(&acpi_pci_root_lock);
>>>
>>> -     acpi_pci_irq_del_prt(root->segment, root->secondary.start);
>>>  end:
>>>       kfree(root);
>>>       return result;
>>> @@ -610,8 +598,6 @@ end:
>>>
>>>  static void acpi_pci_root_remove(struct acpi_device *device)
>>>  {
>>> -     acpi_status status;
>>> -     acpi_handle handle;
>>>       struct acpi_pci_root *root = acpi_driver_data(device);
>>>       struct acpi_pci_driver *driver;
>>>
>>> @@ -626,10 +612,6 @@ static void acpi_pci_root_remove(struct
>>>       device_set_run_wake(root->bus->bridge, false);
>>>       pci_acpi_remove_bus_pm_notifier(device);
>>>
>>> -     status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
>>> -     if (ACPI_SUCCESS(status))
>>> -             acpi_pci_irq_del_prt(root->segment, root->secondary.start);
>>> -
>>>       pci_remove_root_bus(root->bus);
>>>
>>>       mutex_lock(&acpi_pci_root_lock);
>>> Index: linux-2.6/drivers/pci/pci-acpi.c
>>> ===================================================================
>>> --- linux-2.6.orig/drivers/pci/pci-acpi.c
>>> +++ linux-2.6/drivers/pci/pci-acpi.c
>>> @@ -307,25 +307,6 @@ static void pci_acpi_setup(struct device
>>>       struct pci_dev *pci_dev = to_pci_dev(dev);
>>>       acpi_handle handle = ACPI_HANDLE(dev);
>>>       struct acpi_device *adev;
>>> -     acpi_status status;
>>> -     acpi_handle dummy;
>>> -
>>> -     /*
>>> -      * Evaluate and parse _PRT, if exists.  This code allows parsing of
>>> -      * _PRT objects within the scope of non-bridge devices.  Note that
>>> -      * _PRTs within the scope of a PCI bridge assume the bridge's
>>> -      * subordinate bus number.
>>> -      *
>>> -      * TBD: Can _PRTs exist within the scope of non-bridge PCI devices?
>>> -      */
>>> -     status = acpi_get_handle(handle, METHOD_NAME__PRT, &dummy);
>>> -     if (ACPI_SUCCESS(status)) {
>>> -             unsigned char bus;
>>> -
>>> -             bus = pci_dev->subordinate ?
>>> -                     pci_dev->subordinate->number : pci_dev->bus->number;
>>> -             acpi_pci_irq_add_prt(handle, pci_domain_nr(pci_dev->bus), bus);
>>> -     }
>>>
>>>       if (acpi_bus_get_device(handle, &adev) || !adev->wakeup.flags.valid)
>>>               return;
>>> @@ -340,7 +321,6 @@ static void pci_acpi_setup(struct device
>>>
>>>  static void pci_acpi_cleanup(struct device *dev)
>>>  {
>>> -     struct pci_dev *pci_dev = to_pci_dev(dev);
>>>       acpi_handle handle = ACPI_HANDLE(dev);
>>>       struct acpi_device *adev;
>>>
>>> @@ -349,10 +329,6 @@ static void pci_acpi_cleanup(struct devi
>>>               device_set_run_wake(dev, false);
>>>               pci_acpi_remove_pm_notifier(adev);
>>>       }
>>> -
>>> -     if (pci_dev->subordinate)
>>> -             acpi_pci_irq_del_prt(pci_domain_nr(pci_dev->bus),
>>> -                                  pci_dev->subordinate->number);
>>>  }
>>>
>>>  static struct acpi_bus_type acpi_pci_bus = {
>>> Index: linux-2.6/include/acpi/acpi_drivers.h
>>> ===================================================================
>>> --- linux-2.6.orig/include/acpi/acpi_drivers.h
>>> +++ linux-2.6/include/acpi/acpi_drivers.h
>>> @@ -90,11 +90,6 @@ int acpi_pci_link_allocate_irq(acpi_hand
>>>                              int *polarity, char **name);
>>>  int acpi_pci_link_free_irq(acpi_handle handle);
>>>
>>> -/* ACPI PCI Interrupt Routing (pci_irq.c) */
>>> -
>>> -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus);
>>> -void acpi_pci_irq_del_prt(int segment, int bus);
>>> -
>>>  /* ACPI PCI Device Binding (pci_bind.c) */
>>>
>>>  struct pci_bus;
>> --
>> I speak only for myself.
>> Rafael J. Wysocki, Intel Open Source Technology Center.
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Yinghai Lu - Feb. 16, 2013, 1:26 a.m.
On Fri, Feb 15, 2013 at 4:39 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
> On Thu, Feb 14, 2013 at 5:50 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> On Tue, Feb 12, 2013 at 12:22 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
>>> On Tuesday, February 12, 2013 11:11:23 AM Yinghai Lu wrote:
>>>> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
>>>>
>>>> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
>>>> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
>>>>
>>>> bisect to
>>>> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
>>>> |     PCI: Put pci_dev in device tree as early as possible
>>>>
>>>> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
>>>> are scanned.
>>>>
>>>> Bjorn said:
>>>>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>>>>  after enumerating everything below a bridge, and it will prevent us
>>>>  from doing any bus number reassignment for hotplug.
>>>>
>>>>  I think we should remove the bus numbers from the cached _PRT (or
>>>>  maybe even remove the _PRT caching completely).  When we enable a PCI
>>>>  device's IRQ, we should search up the PCI device tree looking for a
>>>>  _PRT associated with each node, and applying normal PCI bridge
>>>>  swizzling when we don't find a _PRT.  I think this can be done without
>>>>  using PCI bus numbers at all.
>>>>
>>>> So here we try to remove _PRT caching completely.
>>>>
>>>> -v2: check !handle early.
>>>>
>>>> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
>>>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>>>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
>>>
>>> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>>
>>>> ---
>>>>  drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
>>>>  drivers/acpi/pci_root.c     |   18 --------
>>>>  drivers/pci/pci-acpi.c      |   24 -----------
>>>>  include/acpi/acpi_drivers.h |    5 --
>>>>  4 files changed, 38 insertions(+), 104 deletions(-)
>>
>> Bjorn,
>>
>> Can you put this one into pci/next?
>
> I'm not sure what this patch is based on or what the best way to merge
> it is.  It doesn't apply cleanly to my next or
> pci/yinghai-root-bus-hotplug branches.

My fault, that is based on pci/next + pm/linux-next

linux-next removed
acpi_power_resource_(un)register_device ...

>
> I did apply it manually on top of pci/yinghai-root-bus-hotplug to try
> it out, but we need to tweak the messages a little bit.
>
> Previously we printed "ACPI: PCI Interrupt Routing Table [%s._PRT]"
> once when loading it, which was fine.  Now we print it every time we
> look at a _PRT, which is too much because it isn't really adding any
> information.
>
> We also print "ACPI Exception: AE_NOT_FOUND, Evaluating _PRT
> [AE_NOT_FOUND] (20121018/pci_irq-259)" if we find ACPI nodes without
> _PRTs, which we shouldn't do, because that's a common and normal
> situation.

Sure. Can you have separated patch to do that ?

Or want me to resend the patch.

Thanks

Yinghai
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Yinghai Lu - Feb. 16, 2013, 1:37 a.m.
On Fri, Feb 15, 2013 at 5:26 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Feb 15, 2013 at 4:39 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
>> On Thu, Feb 14, 2013 at 5:50 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>> On Tue, Feb 12, 2013 at 12:22 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
>>>> On Tuesday, February 12, 2013 11:11:23 AM Yinghai Lu wrote:
>>>>> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
>>>>>
>>>>> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
>>>>> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
>>>>>
>>>>> bisect to
>>>>> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
>>>>> |     PCI: Put pci_dev in device tree as early as possible
>>>>>
>>>>> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
>>>>> are scanned.
>>>>>
>>>>> Bjorn said:
>>>>>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>>>>>  after enumerating everything below a bridge, and it will prevent us
>>>>>  from doing any bus number reassignment for hotplug.
>>>>>
>>>>>  I think we should remove the bus numbers from the cached _PRT (or
>>>>>  maybe even remove the _PRT caching completely).  When we enable a PCI
>>>>>  device's IRQ, we should search up the PCI device tree looking for a
>>>>>  _PRT associated with each node, and applying normal PCI bridge
>>>>>  swizzling when we don't find a _PRT.  I think this can be done without
>>>>>  using PCI bus numbers at all.
>>>>>
>>>>> So here we try to remove _PRT caching completely.
>>>>>
>>>>> -v2: check !handle early.
>>>>>
>>>>> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
>>>>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>>>>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
>>>>
>>>> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>>>
>>>>> ---
>>>>>  drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
>>>>>  drivers/acpi/pci_root.c     |   18 --------
>>>>>  drivers/pci/pci-acpi.c      |   24 -----------
>>>>>  include/acpi/acpi_drivers.h |    5 --
>>>>>  4 files changed, 38 insertions(+), 104 deletions(-)
>>>
>>> Bjorn,
>>>
>>> Can you put this one into pci/next?
>>
>> I'm not sure what this patch is based on or what the best way to merge
>> it is.  It doesn't apply cleanly to my next or
>> pci/yinghai-root-bus-hotplug branches.
>
> My fault, that is based on pci/next + pm/linux-next
>
> linux-next removed
> acpi_power_resource_(un)register_device ...
>
>>
>> I did apply it manually on top of pci/yinghai-root-bus-hotplug to try
>> it out, but we need to tweak the messages a little bit.
>>
>> Previously we printed "ACPI: PCI Interrupt Routing Table [%s._PRT]"
>> once when loading it, which was fine.  Now we print it every time we
>> look at a _PRT, which is too much because it isn't really adding any
>> information.
>>
>> We also print "ACPI Exception: AE_NOT_FOUND, Evaluating _PRT
>> [AE_NOT_FOUND] (20121018/pci_irq-259)" if we find ACPI nodes without
>> _PRTs, which we shouldn't do, because that's a common and normal
>> situation.
>
> Sure. Can you have separated patch to do that ?
>
> Or want me to resend the patch.

Please check attached updated version that remove print out ...

and it could be applied cleanly on top of pci/yinghai-root-bus-hotplug

Thanks

Yinghai
Bjorn Helgaas - Feb. 19, 2013, 6:51 p.m.
On Fri, Feb 15, 2013 at 6:37 PM, Yinghai Lu <yinghai@kernel.org> wrote:
> On Fri, Feb 15, 2013 at 5:26 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>> On Fri, Feb 15, 2013 at 4:39 PM, Bjorn Helgaas <bhelgaas@google.com> wrote:
>>> On Thu, Feb 14, 2013 at 5:50 PM, Yinghai Lu <yinghai@kernel.org> wrote:
>>>> On Tue, Feb 12, 2013 at 12:22 PM, Rafael J. Wysocki <rjw@sisk.pl> wrote:
>>>>> On Tuesday, February 12, 2013 11:11:23 AM Yinghai Lu wrote:
>>>>>> Peter Hurley found "irq 18 nobody cared" with pci-next, and dmesg has
>>>>>>
>>>>>> [    8.983246] pci 0000:00:1e.0: can't derive routing for PCI INT A
>>>>>> [    8.983600] snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5
>>>>>>
>>>>>> bisect to
>>>>>> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4
>>>>>> |     PCI: Put pci_dev in device tree as early as possible
>>>>>>
>>>>>> It turns out we need to call acpi_pci_irq_add_prt() after the pci bridges
>>>>>> are scanned.
>>>>>>
>>>>>> Bjorn said:
>>>>>>  The bus number binding means acpi_pci_irq_add_prt() has to happen
>>>>>>  after enumerating everything below a bridge, and it will prevent us
>>>>>>  from doing any bus number reassignment for hotplug.
>>>>>>
>>>>>>  I think we should remove the bus numbers from the cached _PRT (or
>>>>>>  maybe even remove the _PRT caching completely).  When we enable a PCI
>>>>>>  device's IRQ, we should search up the PCI device tree looking for a
>>>>>>  _PRT associated with each node, and applying normal PCI bridge
>>>>>>  swizzling when we don't find a _PRT.  I think this can be done without
>>>>>>  using PCI bus numbers at all.
>>>>>>
>>>>>> So here we try to remove _PRT caching completely.
>>>>>>
>>>>>> -v2: check !handle early.
>>>>>>
>>>>>> Reported-and-tested-by: Peter Hurley <peter@hurleysoftware.com>
>>>>>> Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
>>>>>> Signed-off-by: Yinghai Lu <yinghai@kernel.org>
>>>>>
>>>>> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>>>>
>>>>>> ---
>>>>>>  drivers/acpi/pci_irq.c      |   95 +++++++++++++++++---------------------------
>>>>>>  drivers/acpi/pci_root.c     |   18 --------
>>>>>>  drivers/pci/pci-acpi.c      |   24 -----------
>>>>>>  include/acpi/acpi_drivers.h |    5 --
>>>>>>  4 files changed, 38 insertions(+), 104 deletions(-)
>>>>
>>>> Bjorn,
>>>>
>>>> Can you put this one into pci/next?
>>>
>>> I'm not sure what this patch is based on or what the best way to merge
>>> it is.  It doesn't apply cleanly to my next or
>>> pci/yinghai-root-bus-hotplug branches.
>>
>> My fault, that is based on pci/next + pm/linux-next
>>
>> linux-next removed
>> acpi_power_resource_(un)register_device ...
>>
>>>
>>> I did apply it manually on top of pci/yinghai-root-bus-hotplug to try
>>> it out, but we need to tweak the messages a little bit.
>>>
>>> Previously we printed "ACPI: PCI Interrupt Routing Table [%s._PRT]"
>>> once when loading it, which was fine.  Now we print it every time we
>>> look at a _PRT, which is too much because it isn't really adding any
>>> information.
>>>
>>> We also print "ACPI Exception: AE_NOT_FOUND, Evaluating _PRT
>>> [AE_NOT_FOUND] (20121018/pci_irq-259)" if we find ACPI nodes without
>>> _PRTs, which we shouldn't do, because that's a common and normal
>>> situation.
>>
>> Sure. Can you have separated patch to do that ?
>>
>> Or want me to resend the patch.
>
> Please check attached updated version that remove print out ...
>
> and it could be applied cleanly on top of pci/yinghai-root-bus-hotplug

Thanks, I applied this to pci/yinghai-root-bus-hotplug and merged it
into my next branch.

Bjorn
--
To unsubscribe from this list: send the line "unsubscribe linux-pci" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Patch

Index: linux-2.6/drivers/acpi/pci_irq.c
===================================================================
--- linux-2.6.orig/drivers/acpi/pci_irq.c
+++ linux-2.6/drivers/acpi/pci_irq.c
@@ -53,9 +53,6 @@  struct acpi_prt_entry {
 	u32			index;		/* GSI, or link _CRS index */
 };
 
-static LIST_HEAD(acpi_prt_list);
-static DEFINE_SPINLOCK(acpi_prt_lock);
-
 static inline char pin_name(int pin)
 {
 	return 'A' + pin - 1;
@@ -65,28 +62,6 @@  static inline char pin_name(int pin)
                          PCI IRQ Routing Table (PRT) Support
    -------------------------------------------------------------------------- */
 
-static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
-							  int pin)
-{
-	struct acpi_prt_entry *entry;
-	int segment = pci_domain_nr(dev->bus);
-	int bus = dev->bus->number;
-	int device = PCI_SLOT(dev->devfn);
-
-	spin_lock(&acpi_prt_lock);
-	list_for_each_entry(entry, &acpi_prt_list, list) {
-		if ((segment == entry->id.segment)
-		    && (bus == entry->id.bus)
-		    && (device == entry->id.device)
-		    && (pin == entry->pin)) {
-			spin_unlock(&acpi_prt_lock);
-			return entry;
-		}
-	}
-	spin_unlock(&acpi_prt_lock);
-	return NULL;
-}
-
 /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
 static const struct dmi_system_id medion_md9580[] = {
 	{
@@ -184,11 +159,19 @@  static void do_prt_fixups(struct acpi_pr
 	}
 }
 
-static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus,
-				  struct acpi_pci_routing_table *prt)
+static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
+				  int pin, struct acpi_pci_routing_table *prt,
+				  struct acpi_prt_entry **entry_ptr)
 {
+	int segment = pci_domain_nr(dev->bus);
+	int bus = dev->bus->number;
+	int device = PCI_SLOT(dev->devfn);
 	struct acpi_prt_entry *entry;
 
+	if (((prt->address >> 16) & 0xffff) != device ||
+	    prt->pin + 1 != pin)
+		return -ENODEV;
+
 	entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
 	if (!entry)
 		return -ENOMEM;
@@ -237,26 +220,33 @@  static int acpi_pci_irq_add_entry(acpi_h
 			      entry->id.device, pin_name(entry->pin),
 			      prt->source, entry->index));
 
-	spin_lock(&acpi_prt_lock);
-	list_add_tail(&entry->list, &acpi_prt_list);
-	spin_unlock(&acpi_prt_lock);
+	*entry_ptr = entry;
 
 	return 0;
 }
 
-int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
+static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
+			  int pin, struct acpi_prt_entry **entry_ptr)
 {
 	acpi_status status;
 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 	struct acpi_pci_routing_table *entry;
+	acpi_handle handle = NULL;
+
+	if (dev->bus->bridge)
+		handle = ACPI_HANDLE(dev->bus->bridge);
+
+	if (!handle)
+		return -ENODEV;
 
 	/* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
 	status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
 	if (ACPI_FAILURE(status))
 		return -ENODEV;
 
-	printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
-	       (char *) buffer.pointer);
+	dev_printk(KERN_DEBUG, &dev->dev,
+			"ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
+		       (char *) buffer.pointer);
 
 	kfree(buffer.pointer);
 
@@ -273,7 +263,9 @@  int acpi_pci_irq_add_prt(acpi_handle han
 
 	entry = buffer.pointer;
 	while (entry && (entry->length > 0)) {
-		acpi_pci_irq_add_entry(handle, segment, bus, entry);
+		if (!acpi_pci_irq_check_entry(handle, dev, pin,
+						 entry, entry_ptr))
+			break;
 		entry = (struct acpi_pci_routing_table *)
 		    ((unsigned long)entry + entry->length);
 	}
@@ -282,23 +274,6 @@  int acpi_pci_irq_add_prt(acpi_handle han
 	return 0;
 }
 
-void acpi_pci_irq_del_prt(int segment, int bus)
-{
-	struct acpi_prt_entry *entry, *tmp;
-
-	printk(KERN_DEBUG
-	       "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
-	       segment, bus);
-	spin_lock(&acpi_prt_lock);
-	list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
-		if (segment == entry->id.segment && bus == entry->id.bus) {
-			list_del(&entry->list);
-			kfree(entry);
-		}
-	}
-	spin_unlock(&acpi_prt_lock);
-}
-
 /* --------------------------------------------------------------------------
                           PCI Interrupt Routing Support
    -------------------------------------------------------------------------- */
@@ -359,12 +334,13 @@  static int acpi_reroute_boot_interrupt(s
 
 static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
 {
-	struct acpi_prt_entry *entry;
+	struct acpi_prt_entry *entry = NULL;
 	struct pci_dev *bridge;
 	u8 bridge_pin, orig_pin = pin;
+	int ret;
 
-	entry = acpi_pci_irq_find_prt_entry(dev, pin);
-	if (entry) {
+	ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
+	if (!ret && entry) {
 #ifdef CONFIG_X86_IO_APIC
 		acpi_reroute_boot_interrupt(dev, entry);
 #endif /* CONFIG_X86_IO_APIC */
@@ -373,7 +349,7 @@  static struct acpi_prt_entry *acpi_pci_i
 		return entry;
 	}
 
-	/* 
+	/*
 	 * Attempt to derive an IRQ for this device from a parent bridge's
 	 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
 	 */
@@ -393,8 +369,8 @@  static struct acpi_prt_entry *acpi_pci_i
 			pin = bridge_pin;
 		}
 
-		entry = acpi_pci_irq_find_prt_entry(bridge, pin);
-		if (entry) {
+		ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
+		if (!ret && entry) {
 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 					 "Derived GSI for %s INT %c from %s\n",
 					 pci_name(dev), pin_name(orig_pin),
@@ -470,6 +446,7 @@  int acpi_pci_irq_enable(struct pci_dev *
 			dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
 				 pin_name(pin));
 		}
+
 		return 0;
 	}
 
@@ -477,6 +454,7 @@  int acpi_pci_irq_enable(struct pci_dev *
 	if (rc < 0) {
 		dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
 			 pin_name(pin));
+		kfree(entry);
 		return rc;
 	}
 	dev->irq = rc;
@@ -491,6 +469,7 @@  int acpi_pci_irq_enable(struct pci_dev *
 		(triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
 		(polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
 
+	kfree(entry);
 	return 0;
 }
 
@@ -513,6 +492,8 @@  void acpi_pci_irq_disable(struct pci_dev
 	else
 		gsi = entry->index;
 
+	kfree(entry);
+
 	/*
 	 * TBD: It might be worth clearing dev->irq by magic constant
 	 * (e.g. PCI_UNDEFINED_IRQ).
Index: linux-2.6/drivers/acpi/pci_root.c
===================================================================
--- linux-2.6.orig/drivers/acpi/pci_root.c
+++ linux-2.6/drivers/acpi/pci_root.c
@@ -413,7 +413,6 @@  static int acpi_pci_root_add(struct acpi
 	acpi_status status;
 	int result;
 	struct acpi_pci_root *root;
-	acpi_handle handle;
 	struct acpi_pci_driver *driver;
 	u32 flags, base_flags;
 	bool is_osc_granted = false;
@@ -468,16 +467,6 @@  static int acpi_pci_root_add(struct acpi
 	       acpi_device_name(device), acpi_device_bid(device),
 	       root->segment, &root->secondary);
 
-	/*
-	 * PCI Routing Table
-	 * -----------------
-	 * Evaluate and parse _PRT, if exists.
-	 */
-	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
-	if (ACPI_SUCCESS(status))
-		result = acpi_pci_irq_add_prt(device->handle, root->segment,
-					      root->secondary.start);
-
 	root->mcfg_addr = acpi_pci_root_get_mcfg_addr(device->handle);
 
 	/*
@@ -602,7 +591,6 @@  out_del_root:
 	list_del(&root->node);
 	mutex_unlock(&acpi_pci_root_lock);
 
-	acpi_pci_irq_del_prt(root->segment, root->secondary.start);
 end:
 	kfree(root);
 	return result;
@@ -610,8 +598,6 @@  end:
 
 static void acpi_pci_root_remove(struct acpi_device *device)
 {
-	acpi_status status;
-	acpi_handle handle;
 	struct acpi_pci_root *root = acpi_driver_data(device);
 	struct acpi_pci_driver *driver;
 
@@ -626,10 +612,6 @@  static void acpi_pci_root_remove(struct
 	device_set_run_wake(root->bus->bridge, false);
 	pci_acpi_remove_bus_pm_notifier(device);
 
-	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
-	if (ACPI_SUCCESS(status))
-		acpi_pci_irq_del_prt(root->segment, root->secondary.start);
-
 	pci_remove_root_bus(root->bus);
 
 	mutex_lock(&acpi_pci_root_lock);
Index: linux-2.6/drivers/pci/pci-acpi.c
===================================================================
--- linux-2.6.orig/drivers/pci/pci-acpi.c
+++ linux-2.6/drivers/pci/pci-acpi.c
@@ -307,25 +307,6 @@  static void pci_acpi_setup(struct device
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 	acpi_handle handle = ACPI_HANDLE(dev);
 	struct acpi_device *adev;
-	acpi_status status;
-	acpi_handle dummy;
-
-	/*
-	 * Evaluate and parse _PRT, if exists.  This code allows parsing of
-	 * _PRT objects within the scope of non-bridge devices.  Note that
-	 * _PRTs within the scope of a PCI bridge assume the bridge's
-	 * subordinate bus number.
-	 *
-	 * TBD: Can _PRTs exist within the scope of non-bridge PCI devices?
-	 */
-	status = acpi_get_handle(handle, METHOD_NAME__PRT, &dummy);
-	if (ACPI_SUCCESS(status)) {
-		unsigned char bus;
-
-		bus = pci_dev->subordinate ?
-			pci_dev->subordinate->number : pci_dev->bus->number;
-		acpi_pci_irq_add_prt(handle, pci_domain_nr(pci_dev->bus), bus);
-	}
 
 	if (acpi_bus_get_device(handle, &adev) || !adev->wakeup.flags.valid)
 		return;
@@ -340,7 +321,6 @@  static void pci_acpi_setup(struct device
 
 static void pci_acpi_cleanup(struct device *dev)
 {
-	struct pci_dev *pci_dev = to_pci_dev(dev);
 	acpi_handle handle = ACPI_HANDLE(dev);
 	struct acpi_device *adev;
 
@@ -349,10 +329,6 @@  static void pci_acpi_cleanup(struct devi
 		device_set_run_wake(dev, false);
 		pci_acpi_remove_pm_notifier(adev);
 	}
-
-	if (pci_dev->subordinate)
-		acpi_pci_irq_del_prt(pci_domain_nr(pci_dev->bus),
-				     pci_dev->subordinate->number);
 }
 
 static struct acpi_bus_type acpi_pci_bus = {
Index: linux-2.6/include/acpi/acpi_drivers.h
===================================================================
--- linux-2.6.orig/include/acpi/acpi_drivers.h
+++ linux-2.6/include/acpi/acpi_drivers.h
@@ -90,11 +90,6 @@  int acpi_pci_link_allocate_irq(acpi_hand
 			       int *polarity, char **name);
 int acpi_pci_link_free_irq(acpi_handle handle);
 
-/* ACPI PCI Interrupt Routing (pci_irq.c) */
-
-int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus);
-void acpi_pci_irq_del_prt(int segment, int bus);
-
 /* ACPI PCI Device Binding (pci_bind.c) */
 
 struct pci_bus;