linux/drivers/pci/hotplug/pciehp_pci.c
Lukas Wunner 5790a9c78e PCI: pciehp: Unify controller and slot structs
pciehp was originally introduced together with shpchp in a single
commit, c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI Express hot-plug
drivers"):
https://git.kernel.org/tglx/history/c/c16b4b14d980

shpchp supports up to 31 slots per controller, hence uses separate slot
and controller structs.  pciehp has a 1:1 relationship between slot and
controller and therefore never required this separation.  Nevertheless,
because much of the code had been copy-pasted between the two drivers,
pciehp likewise uses separate structs to this very day.

The artificial separation of data structures adds unnecessary complexity
and bloat to pciehp and requires constantly chasing pointers at runtime.

Simplify the driver by merging struct slot into struct controller.
Merge the slot constructor pcie_init_slot() and the destructor
pcie_cleanup_slot() into the controller counterparts.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-18 17:52:15 -05:00

121 lines
3.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* PCI Express Hot Plug Controller Driver
*
* Copyright (C) 1995,2001 Compaq Computer Corporation
* Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
* Copyright (C) 2001 IBM Corp.
* Copyright (C) 2003-2004 Intel Corporation
*
* All rights reserved.
*
* Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
*
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include "../pci.h"
#include "pciehp.h"
/**
* pciehp_configure_device() - enumerate PCI devices below a hotplug bridge
* @ctrl: PCIe hotplug controller
*
* Enumerate PCI devices below a hotplug bridge and add them to the system.
* Return 0 on success, %-EEXIST if the devices are already enumerated or
* %-ENODEV if enumeration failed.
*/
int pciehp_configure_device(struct controller *ctrl)
{
struct pci_dev *dev;
struct pci_dev *bridge = ctrl->pcie->port;
struct pci_bus *parent = bridge->subordinate;
int num, ret = 0;
pci_lock_rescan_remove();
dev = pci_get_slot(parent, PCI_DEVFN(0, 0));
if (dev) {
/*
* The device is already there. Either configured by the
* boot firmware or a previous hotplug event.
*/
ctrl_dbg(ctrl, "Device %s already exists at %04x:%02x:00, skipping hot-add\n",
pci_name(dev), pci_domain_nr(parent), parent->number);
pci_dev_put(dev);
ret = -EEXIST;
goto out;
}
num = pci_scan_slot(parent, PCI_DEVFN(0, 0));
if (num == 0) {
ctrl_err(ctrl, "No new device found\n");
ret = -ENODEV;
goto out;
}
for_each_pci_bridge(dev, parent)
pci_hp_add_bridge(dev);
pci_assign_unassigned_bridge_resources(bridge);
pcie_bus_configure_settings(parent);
pci_bus_add_devices(parent);
out:
pci_unlock_rescan_remove();
return ret;
}
/**
* pciehp_unconfigure_device() - remove PCI devices below a hotplug bridge
* @ctrl: PCIe hotplug controller
* @presence: whether the card is still present in the slot;
* true for safe removal via sysfs or an Attention Button press,
* false for surprise removal
*
* Unbind PCI devices below a hotplug bridge from their drivers and remove
* them from the system. Safely removed devices are quiesced. Surprise
* removed devices are marked as such to prevent further accesses.
*/
void pciehp_unconfigure_device(struct controller *ctrl, bool presence)
{
struct pci_dev *dev, *temp;
struct pci_bus *parent = ctrl->pcie->port->subordinate;
u16 command;
ctrl_dbg(ctrl, "%s: domain:bus:dev = %04x:%02x:00\n",
__func__, pci_domain_nr(parent), parent->number);
if (!presence)
pci_walk_bus(parent, pci_dev_set_disconnected, NULL);
pci_lock_rescan_remove();
/*
* Stopping an SR-IOV PF device removes all the associated VFs,
* which will update the bus->devices list and confuse the
* iterator. Therefore, iterate in reverse so we remove the VFs
* first, then the PF. We do the same in pci_stop_bus_device().
*/
list_for_each_entry_safe_reverse(dev, temp, &parent->devices,
bus_list) {
pci_dev_get(dev);
pci_stop_and_remove_bus_device(dev);
/*
* Ensure that no new Requests will be generated from
* the device.
*/
if (presence) {
pci_read_config_word(dev, PCI_COMMAND, &command);
command &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_SERR);
command |= PCI_COMMAND_INTX_DISABLE;
pci_write_config_word(dev, PCI_COMMAND, command);
}
pci_dev_put(dev);
}
pci_unlock_rescan_remove();
}