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ACPI: eviscerate pci_bind.c
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Now that we can dynamically convert an ACPI CA handle to a
struct pci_dev at runtime, there's no need to statically bind
them during boot.

acpi_pci_bind/unbind are vastly simplified, and are only used
to evaluate _PRT methods on P2P bridges and non-bridge children.

This patch also changes the time-space tradeoff ever so slightly.

Looking up the ACPI-PCI binding is never in the performance path, and by
eliminating this caching, we save 24 bytes for each _ADR device in the
ACPI namespace.

This patch lays further groundwork to eventually eliminate
the acpi_driver_ops.bind callback.

Signed-off-by: Alex Chiang <achiang@hp.com>
Acked-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Len Brown <len.brown@intel.com>
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Alexander Chiang authored and Len Brown committed Jun 18, 2009
1 parent c22d7f5 commit 499650d
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Showing 3 changed files with 39 additions and 211 deletions.
245 changes: 37 additions & 208 deletions drivers/acpi/pci_bind.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -24,12 +24,7 @@
*/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/pm.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <acpi/acpi_bus.h>
Expand Down Expand Up @@ -111,238 +106,72 @@ EXPORT_SYMBOL(acpi_get_pci_id);

static int acpi_pci_unbind(struct acpi_device *device)
{
int result = 0;
acpi_status status;
struct acpi_pci_data *data;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };


if (!device || !device->parent)
return -EINVAL;

status = acpi_get_name(device->handle, ACPI_FULL_PATHNAME, &buffer);
if (ACPI_FAILURE(status))
return -ENODEV;

ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unbinding PCI device [%s]...\n",
(char *) buffer.pointer));
kfree(buffer.pointer);
struct pci_dev *dev;

status =
acpi_get_data(device->handle, acpi_pci_data_handler,
(void **)&data);
if (ACPI_FAILURE(status)) {
result = -ENODEV;
goto end;
}
dev = acpi_get_pci_dev(device->handle);
if (!dev)
return 0;

status = acpi_detach_data(device->handle, acpi_pci_data_handler);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Unable to detach data from device %s",
acpi_device_bid(device)));
result = -ENODEV;
goto end;
}
if (data->dev->subordinate) {
acpi_pci_irq_del_prt(data->id.segment, data->bus->number);
}
pci_dev_put(data->dev);
kfree(data);
if (dev->subordinate)
acpi_pci_irq_del_prt(pci_domain_nr(dev->bus),
dev->subordinate->number);

end:
return result;
pci_dev_put(dev);
return 0;
}

static int acpi_pci_bind(struct acpi_device *device)
{
int result = 0;
acpi_status status;
struct acpi_pci_data *data;
struct acpi_pci_data *pdata;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_handle handle;
unsigned char bus;
struct pci_dev *dev;

if (!device || !device->parent)
return -EINVAL;

data = kzalloc(sizeof(struct acpi_pci_data), GFP_KERNEL);
if (!data)
return -ENOMEM;

status = acpi_get_name(device->handle, ACPI_FULL_PATHNAME, &buffer);
if (ACPI_FAILURE(status)) {
kfree(data);
return -ENODEV;
}

ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Binding PCI device [%s]...\n",
(char *)buffer.pointer));

/*
* Segment & Bus
* -------------
* These are obtained via the parent device's ACPI-PCI context.
*/
status = acpi_get_data(device->parent->handle, acpi_pci_data_handler,
(void **)&pdata);
if (ACPI_FAILURE(status) || !pdata || !pdata->bus) {
ACPI_EXCEPTION((AE_INFO, status,
"Invalid ACPI-PCI context for parent device %s",
acpi_device_bid(device->parent)));
result = -ENODEV;
goto end;
}
data->id.segment = pdata->id.segment;
data->id.bus = pdata->bus->number;

/*
* Device & Function
* -----------------
* These are simply obtained from the device's _ADR method. Note
* that a value of zero is valid.
*/
data->id.device = device->pnp.bus_address >> 16;
data->id.function = device->pnp.bus_address & 0xFFFF;

ACPI_DEBUG_PRINT((ACPI_DB_INFO, "...to %04x:%02x:%02x.%d\n",
data->id.segment, data->id.bus, data->id.device,
data->id.function));

/*
* TBD: Support slot devices (e.g. function=0xFFFF).
*/

/*
* Locate PCI Device
* -----------------
* Locate matching device in PCI namespace. If it doesn't exist
* this typically means that the device isn't currently inserted
* (e.g. docking station, port replicator, etc.).
*/
data->dev = pci_get_slot(pdata->bus,
PCI_DEVFN(data->id.device, data->id.function));
if (!data->dev) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Device %04x:%02x:%02x.%d not present in PCI namespace\n",
data->id.segment, data->id.bus,
data->id.device, data->id.function));
result = -ENODEV;
goto end;
}
if (!data->dev->bus) {
printk(KERN_ERR PREFIX
"Device %04x:%02x:%02x.%d has invalid 'bus' field\n",
data->id.segment, data->id.bus,
data->id.device, data->id.function);
result = -ENODEV;
goto end;
}
dev = acpi_get_pci_dev(device->handle);
if (!dev)
return 0;

/*
* PCI Bridge?
* -----------
* If so, set the 'bus' field and install the 'bind' function to
* facilitate callbacks for all of its children.
* Install the 'bind' function to facilitate callbacks for
* children of the P2P bridge.
*/
if (data->dev->subordinate) {
if (dev->subordinate) {
ACPI_DEBUG_PRINT((ACPI_DB_INFO,
"Device %04x:%02x:%02x.%d is a PCI bridge\n",
data->id.segment, data->id.bus,
data->id.device, data->id.function));
data->bus = data->dev->subordinate;
pci_domain_nr(dev->bus), dev->bus->number,
PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn)));
device->ops.bind = acpi_pci_bind;
device->ops.unbind = acpi_pci_unbind;
}

/*
* Attach ACPI-PCI Context
* -----------------------
* Thus binding the ACPI and PCI devices.
*/
status = acpi_attach_data(device->handle, acpi_pci_data_handler, data);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Unable to attach ACPI-PCI context to device %s",
acpi_device_bid(device)));
result = -ENODEV;
goto end;
}

/*
* PCI Routing Table
* -----------------
* Evaluate and parse _PRT, if exists. This code is independent of
* PCI bridges (above) to allow 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.
* 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(device->handle, METHOD_NAME__PRT, &handle);
if (ACPI_SUCCESS(status)) {
if (data->bus) /* PCI-PCI bridge */
acpi_pci_irq_add_prt(device->handle, data->id.segment,
data->bus->number);
else /* non-bridge PCI device */
acpi_pci_irq_add_prt(device->handle, data->id.segment,
data->id.bus);
}

end:
kfree(buffer.pointer);
if (result) {
pci_dev_put(data->dev);
kfree(data);
}
return result;
}
if (ACPI_FAILURE(status))
goto out;

int
acpi_pci_bind_root(struct acpi_device *device,
struct acpi_pci_id *id, struct pci_bus *bus)
{
int result = 0;
acpi_status status;
struct acpi_pci_data *data = NULL;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
if (dev->subordinate)
bus = dev->subordinate->number;
else
bus = dev->bus->number;

if (!device || !id || !bus) {
return -EINVAL;
}
acpi_pci_irq_add_prt(device->handle, pci_domain_nr(dev->bus), bus);

data = kzalloc(sizeof(struct acpi_pci_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
out:
pci_dev_put(dev);
return 0;
}

data->id = *id;
data->bus = bus;
int acpi_pci_bind_root(struct acpi_device *device)
{
device->ops.bind = acpi_pci_bind;
device->ops.unbind = acpi_pci_unbind;

status = acpi_get_name(device->handle, ACPI_FULL_PATHNAME, &buffer);
if (ACPI_FAILURE(status)) {
kfree (data);
return -ENODEV;
}

ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Binding PCI root bridge [%s] to "
"%04x:%02x\n", (char *)buffer.pointer,
id->segment, id->bus));

status = acpi_attach_data(device->handle, acpi_pci_data_handler, data);
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"Unable to attach ACPI-PCI context to device %s",
(char *)buffer.pointer));
result = -ENODEV;
goto end;
}

end:
kfree(buffer.pointer);
if (result != 0)
kfree(data);

return result;
return 0;
}
2 changes: 1 addition & 1 deletion drivers/acpi/pci_root.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -603,7 +603,7 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
* -----------------------
* Thus binding the ACPI and PCI devices.
*/
result = acpi_pci_bind_root(device, &root->id, root->bus);
result = acpi_pci_bind_root(device);
if (result)
goto end;

Expand Down
3 changes: 1 addition & 2 deletions include/acpi/acpi_drivers.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -100,8 +100,7 @@ struct pci_bus;

struct pci_dev *acpi_get_pci_dev(acpi_handle);
acpi_status acpi_get_pci_id(acpi_handle handle, struct acpi_pci_id *id);
int acpi_pci_bind_root(struct acpi_device *device, struct acpi_pci_id *id,
struct pci_bus *bus);
int acpi_pci_bind_root(struct acpi_device *device);

/* Arch-defined function to add a bus to the system */

Expand Down

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