android_kernel_xiaomi_sm8350/drivers/pci/hotplug/rpaphp_pci.c
Jesper Juhl f5c99dfc11 [PATCH] PCI: Reduce nr of ptr derefs in drivers/pci/hotplug/rpaphp_pci.c
Here's a small patch to reduce the nr. of pointer dereferences in
drivers/pci/hotplug/rpaphp_pci.c

Benefits:
 - micro speed optimization due to fewer pointer derefs
 - generated code should be slightly smaller
 - better readability

note: due to lack of both hardware and cross-compile tools this patch is,
      unfortunately, completely untested.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-01-09 12:13:19 -08:00

470 lines
12 KiB
C

/*
* PCI Hot Plug Controller Driver for RPA-compliant PPC64 platform.
* Copyright (C) 2003 Linda Xie <lxie@us.ibm.com>
*
* All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* Send feedback to <lxie@us.ibm.com>
*
*/
#include <linux/pci.h>
#include <linux/string.h>
#include <asm/pci-bridge.h>
#include <asm/rtas.h>
#include <asm/machdep.h>
#include "../pci.h" /* for pci_add_new_bus */
#include "rpaphp.h"
static struct pci_bus *find_bus_among_children(struct pci_bus *bus,
struct device_node *dn)
{
struct pci_bus *child = NULL;
struct list_head *tmp;
struct device_node *busdn;
busdn = pci_bus_to_OF_node(bus);
if (busdn == dn)
return bus;
list_for_each(tmp, &bus->children) {
child = find_bus_among_children(pci_bus_b(tmp), dn);
if (child)
break;
}
return child;
}
struct pci_bus *rpaphp_find_pci_bus(struct device_node *dn)
{
struct pci_dn *pdn = dn->data;
if (!pdn || !pdn->phb || !pdn->phb->bus)
return NULL;
return find_bus_among_children(pdn->phb->bus, dn);
}
EXPORT_SYMBOL_GPL(rpaphp_find_pci_bus);
static int rpaphp_get_sensor_state(struct slot *slot, int *state)
{
int rc;
int setlevel;
rc = rtas_get_sensor(DR_ENTITY_SENSE, slot->index, state);
if (rc < 0) {
if (rc == -EFAULT || rc == -EEXIST) {
dbg("%s: slot must be power up to get sensor-state\n",
__FUNCTION__);
/* some slots have to be powered up
* before get-sensor will succeed.
*/
rc = rtas_set_power_level(slot->power_domain, POWER_ON,
&setlevel);
if (rc < 0) {
dbg("%s: power on slot[%s] failed rc=%d.\n",
__FUNCTION__, slot->name, rc);
} else {
rc = rtas_get_sensor(DR_ENTITY_SENSE,
slot->index, state);
}
} else if (rc == -ENODEV)
info("%s: slot is unusable\n", __FUNCTION__);
else
err("%s failed to get sensor state\n", __FUNCTION__);
}
return rc;
}
/**
* get_pci_adapter_status - get the status of a slot
*
* 0-- slot is empty
* 1-- adapter is configured
* 2-- adapter is not configured
* 3-- not valid
*/
int rpaphp_get_pci_adapter_status(struct slot *slot, int is_init, u8 * value)
{
struct pci_bus *bus;
int state, rc;
*value = NOT_VALID;
rc = rpaphp_get_sensor_state(slot, &state);
if (rc)
goto exit;
if (state == EMPTY)
*value = EMPTY;
else if (state == PRESENT) {
if (!is_init) {
/* at run-time slot->state can be changed by */
/* config/unconfig adapter */
*value = slot->state;
} else {
bus = rpaphp_find_pci_bus(slot->dn);
if (bus && !list_empty(&bus->devices))
*value = CONFIGURED;
else
*value = NOT_CONFIGURED;
}
}
exit:
return rc;
}
/* Must be called before pci_bus_add_devices */
void rpaphp_fixup_new_pci_devices(struct pci_bus *bus, int fix_bus)
{
struct pci_dev *dev;
list_for_each_entry(dev, &bus->devices, bus_list) {
/*
* Skip already-present devices (which are on the
* global device list.)
*/
if (list_empty(&dev->global_list)) {
int i;
/* Need to setup IOMMU tables */
ppc_md.iommu_dev_setup(dev);
if(fix_bus)
pcibios_fixup_device_resources(dev, bus);
pci_read_irq_line(dev);
for (i = 0; i < PCI_NUM_RESOURCES; i++) {
struct resource *r = &dev->resource[i];
if (r->parent || !r->start || !r->flags)
continue;
pci_claim_resource(dev, i);
}
}
}
}
static void rpaphp_eeh_add_bus_device(struct pci_bus *bus)
{
struct pci_dev *dev;
list_for_each_entry(dev, &bus->devices, bus_list) {
eeh_add_device_late(dev);
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
struct pci_bus *subbus = dev->subordinate;
if (subbus)
rpaphp_eeh_add_bus_device (subbus);
}
}
}
static int rpaphp_pci_config_bridge(struct pci_dev *dev)
{
u8 sec_busno;
struct pci_bus *child_bus;
struct pci_dev *child_dev;
dbg("Enter %s: BRIDGE dev=%s\n", __FUNCTION__, pci_name(dev));
/* get busno of downstream bus */
pci_read_config_byte(dev, PCI_SECONDARY_BUS, &sec_busno);
/* add to children of PCI bridge dev->bus */
child_bus = pci_add_new_bus(dev->bus, dev, sec_busno);
if (!child_bus) {
err("%s: could not add second bus\n", __FUNCTION__);
return -EIO;
}
sprintf(child_bus->name, "PCI Bus #%02x", child_bus->number);
/* do pci_scan_child_bus */
pci_scan_child_bus(child_bus);
list_for_each_entry(child_dev, &child_bus->devices, bus_list) {
eeh_add_device_late(child_dev);
}
/* fixup new pci devices without touching bus struct */
rpaphp_fixup_new_pci_devices(child_bus, 0);
/* Make the discovered devices available */
pci_bus_add_devices(child_bus);
return 0;
}
void rpaphp_init_new_devs(struct pci_bus *bus)
{
rpaphp_fixup_new_pci_devices(bus, 0);
rpaphp_eeh_add_bus_device(bus);
}
EXPORT_SYMBOL_GPL(rpaphp_init_new_devs);
/*****************************************************************************
rpaphp_pci_config_slot() will configure all devices under the
given slot->dn and return the the first pci_dev.
*****************************************************************************/
static struct pci_dev *
rpaphp_pci_config_slot(struct pci_bus *bus)
{
struct device_node *dn = pci_bus_to_OF_node(bus);
struct pci_dev *dev = NULL;
int slotno;
int num;
dbg("Enter %s: dn=%s bus=%s\n", __FUNCTION__, dn->full_name, bus->name);
if (!dn || !dn->child)
return NULL;
if (_machine == PLATFORM_PSERIES_LPAR) {
of_scan_bus(dn, bus);
if (list_empty(&bus->devices)) {
err("%s: No new device found\n", __FUNCTION__);
return NULL;
}
rpaphp_init_new_devs(bus);
pci_bus_add_devices(bus);
dev = list_entry(&bus->devices, struct pci_dev, bus_list);
} else {
slotno = PCI_SLOT(PCI_DN(dn->child)->devfn);
/* pci_scan_slot should find all children */
num = pci_scan_slot(bus, PCI_DEVFN(slotno, 0));
if (num) {
rpaphp_fixup_new_pci_devices(bus, 1);
pci_bus_add_devices(bus);
}
if (list_empty(&bus->devices)) {
err("%s: No new device found\n", __FUNCTION__);
return NULL;
}
list_for_each_entry(dev, &bus->devices, bus_list) {
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE)
rpaphp_pci_config_bridge(dev);
rpaphp_eeh_add_bus_device(bus);
}
}
return dev;
}
static void print_slot_pci_funcs(struct pci_bus *bus)
{
struct device_node *dn;
struct pci_dev *dev;
dn = pci_bus_to_OF_node(bus);
if (!dn)
return;
dbg("%s: pci_devs of slot[%s]\n", __FUNCTION__, dn->full_name);
list_for_each_entry (dev, &bus->devices, bus_list)
dbg("\t%s\n", pci_name(dev));
return;
}
int rpaphp_config_pci_adapter(struct pci_bus *bus)
{
struct device_node *dn = pci_bus_to_OF_node(bus);
struct pci_dev *dev;
int rc = -ENODEV;
dbg("Entry %s: slot[%s]\n", __FUNCTION__, dn->full_name);
if (!dn)
goto exit;
eeh_add_device_tree_early(dn);
dev = rpaphp_pci_config_slot(bus);
if (!dev) {
err("%s: can't find any devices.\n", __FUNCTION__);
goto exit;
}
print_slot_pci_funcs(bus);
rc = 0;
exit:
dbg("Exit %s: rc=%d\n", __FUNCTION__, rc);
return rc;
}
EXPORT_SYMBOL_GPL(rpaphp_config_pci_adapter);
static void rpaphp_eeh_remove_bus_device(struct pci_dev *dev)
{
eeh_remove_device(dev);
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
struct pci_bus *bus = dev->subordinate;
struct list_head *ln;
if (!bus)
return;
for (ln = bus->devices.next; ln != &bus->devices; ln = ln->next) {
struct pci_dev *pdev = pci_dev_b(ln);
if (pdev)
rpaphp_eeh_remove_bus_device(pdev);
}
}
return;
}
int rpaphp_unconfig_pci_adapter(struct pci_bus *bus)
{
struct pci_dev *dev, *tmp;
list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
rpaphp_eeh_remove_bus_device(dev);
pci_remove_bus_device(dev);
}
return 0;
}
EXPORT_SYMBOL_GPL(rpaphp_unconfig_pci_adapter);
static int setup_pci_hotplug_slot_info(struct slot *slot)
{
struct hotplug_slot_info *hotplug_slot_info = slot->hotplug_slot->info;
dbg("%s Initilize the PCI slot's hotplug->info structure ...\n",
__FUNCTION__);
rpaphp_get_power_status(slot, &hotplug_slot_info->power_status);
rpaphp_get_pci_adapter_status(slot, 1,
&hotplug_slot_info->adapter_status);
if (hotplug_slot_info->adapter_status == NOT_VALID) {
err("%s: NOT_VALID: skip dn->full_name=%s\n",
__FUNCTION__, slot->dn->full_name);
return -EINVAL;
}
return 0;
}
static void set_slot_name(struct slot *slot)
{
struct pci_bus *bus = slot->bus;
struct pci_dev *bridge;
bridge = bus->self;
if (bridge)
strcpy(slot->name, pci_name(bridge));
else
sprintf(slot->name, "%04x:%02x:00.0", pci_domain_nr(bus),
bus->number);
}
static int setup_pci_slot(struct slot *slot)
{
struct device_node *dn = slot->dn;
struct pci_bus *bus;
BUG_ON(!dn);
bus = rpaphp_find_pci_bus(dn);
if (!bus) {
err("%s: no pci_bus for dn %s\n", __FUNCTION__, dn->full_name);
goto exit_rc;
}
slot->bus = bus;
slot->pci_devs = &bus->devices;
set_slot_name(slot);
/* find slot's pci_dev if it's not empty */
if (slot->hotplug_slot->info->adapter_status == EMPTY) {
slot->state = EMPTY; /* slot is empty */
} else {
/* slot is occupied */
if (!dn->child) {
/* non-empty slot has to have child */
err("%s: slot[%s]'s device_node doesn't have child for adapter\n",
__FUNCTION__, slot->name);
goto exit_rc;
}
if (slot->hotplug_slot->info->adapter_status == NOT_CONFIGURED) {
dbg("%s CONFIGURING pci adapter in slot[%s]\n",
__FUNCTION__, slot->name);
if (rpaphp_config_pci_adapter(slot->bus)) {
err("%s: CONFIG pci adapter failed\n", __FUNCTION__);
goto exit_rc;
}
} else if (slot->hotplug_slot->info->adapter_status != CONFIGURED) {
err("%s: slot[%s]'s adapter_status is NOT_VALID.\n",
__FUNCTION__, slot->name);
goto exit_rc;
}
print_slot_pci_funcs(slot->bus);
if (!list_empty(slot->pci_devs)) {
slot->state = CONFIGURED;
} else {
/* DLPAR add as opposed to
* boot time */
slot->state = NOT_CONFIGURED;
}
}
return 0;
exit_rc:
dealloc_slot_struct(slot);
return -EINVAL;
}
int register_pci_slot(struct slot *slot)
{
int rc = -EINVAL;
if (setup_pci_hotplug_slot_info(slot))
goto exit_rc;
if (setup_pci_slot(slot))
goto exit_rc;
rc = register_slot(slot);
exit_rc:
return rc;
}
int rpaphp_enable_pci_slot(struct slot *slot)
{
int retval = 0, state;
retval = rpaphp_get_sensor_state(slot, &state);
if (retval)
goto exit;
dbg("%s: sensor state[%d]\n", __FUNCTION__, state);
/* if slot is not empty, enable the adapter */
if (state == PRESENT) {
dbg("%s : slot[%s] is occupied.\n", __FUNCTION__, slot->name);
retval = rpaphp_config_pci_adapter(slot->bus);
if (!retval) {
slot->state = CONFIGURED;
info("%s: devices in slot[%s] configured\n",
__FUNCTION__, slot->name);
} else {
slot->state = NOT_CONFIGURED;
dbg("%s: no pci_dev struct for adapter in slot[%s]\n",
__FUNCTION__, slot->name);
}
} else if (state == EMPTY) {
dbg("%s : slot[%s] is empty\n", __FUNCTION__, slot->name);
slot->state = EMPTY;
} else {
err("%s: slot[%s] is in invalid state\n", __FUNCTION__,
slot->name);
slot->state = NOT_VALID;
retval = -EINVAL;
}
exit:
dbg("%s - Exit: rc[%d]\n", __FUNCTION__, retval);
return retval;
}