linux/drivers/pci/hotplug/shpchp_pci.c
rajesh.shah@intel.com 424600f970 [PATCH] shpchp: reduce dependence on ACPI
Reduce the SHPC hotplug driver's dependence on ACPI. We don't
walk the acpi namespace anymore to build a list of bridges and
devices. The remaining interaction with ACPI is to run the
_OSHP method to transition control of hotplug hardware from
system BIOS to the shpc hotplug driver, and to run the _HPP
method to get hotplug device parameters like cache line size,
latency timer and SERR/PERR enable from BIOS.

Note that one of the side effects of this patch is that shpchp
does not enable the hot-added device or its DMA bus mastering
automatically now. It expects the device driver to do that.
This may break some drivers and we will have to fix them as
they are reported.

Signed-off-by: Rajesh Shah <rajesh.shah@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2005-10-28 15:37:00 -07:00

482 lines
12 KiB
C

/*
* Standard 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.
*
* 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 <greg@kroah.com>, <kristen.c.accardi@intel.com>
*
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/workqueue.h>
#include <linux/proc_fs.h>
#include <linux/pci.h>
#include "../pci.h"
#include "shpchp.h"
void program_fw_provided_values(struct pci_dev *dev)
{
u16 pci_cmd, pci_bctl;
struct pci_dev *cdev;
struct hotplug_params hpp = {0x8, 0x40, 0, 0}; /* defaults */
/* Program hpp values for this device */
if (!(dev->hdr_type == PCI_HEADER_TYPE_NORMAL ||
(dev->hdr_type == PCI_HEADER_TYPE_BRIDGE &&
(dev->class >> 8) == PCI_CLASS_BRIDGE_PCI)))
return;
get_hp_params_from_firmware(dev, &hpp);
pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, hpp.cache_line_size);
pci_write_config_byte(dev, PCI_LATENCY_TIMER, hpp.latency_timer);
pci_read_config_word(dev, PCI_COMMAND, &pci_cmd);
if (hpp.enable_serr)
pci_cmd |= PCI_COMMAND_SERR;
else
pci_cmd &= ~PCI_COMMAND_SERR;
if (hpp.enable_perr)
pci_cmd |= PCI_COMMAND_PARITY;
else
pci_cmd &= ~PCI_COMMAND_PARITY;
pci_write_config_word(dev, PCI_COMMAND, pci_cmd);
/* Program bridge control value and child devices */
if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
pci_write_config_byte(dev, PCI_SEC_LATENCY_TIMER,
hpp.latency_timer);
pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &pci_bctl);
if (hpp.enable_serr)
pci_bctl |= PCI_BRIDGE_CTL_SERR;
else
pci_bctl &= ~PCI_BRIDGE_CTL_SERR;
if (hpp.enable_perr)
pci_bctl |= PCI_BRIDGE_CTL_PARITY;
else
pci_bctl &= ~PCI_BRIDGE_CTL_PARITY;
pci_write_config_word(dev, PCI_BRIDGE_CONTROL, pci_bctl);
if (dev->subordinate) {
list_for_each_entry(cdev, &dev->subordinate->devices,
bus_list)
program_fw_provided_values(cdev);
}
}
}
int shpchp_configure_device(struct slot *p_slot)
{
struct pci_dev *dev;
struct pci_bus *parent = p_slot->ctrl->pci_dev->subordinate;
int num, fn;
dev = pci_find_slot(p_slot->bus, PCI_DEVFN(p_slot->device, 0));
if (dev) {
err("Device %s already exists at %x:%x, cannot hot-add\n",
pci_name(dev), p_slot->bus, p_slot->device);
return -EINVAL;
}
num = pci_scan_slot(parent, PCI_DEVFN(p_slot->device, 0));
if (num == 0) {
err("No new device found\n");
return -ENODEV;
}
for (fn = 0; fn < 8; fn++) {
if (!(dev = pci_find_slot(p_slot->bus,
PCI_DEVFN(p_slot->device, fn))))
continue;
if ((dev->class >> 16) == PCI_BASE_CLASS_DISPLAY) {
err("Cannot hot-add display device %s\n",
pci_name(dev));
continue;
}
if ((dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) ||
(dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)) {
/* Find an unused bus number for the new bridge */
struct pci_bus *child;
unsigned char busnr, start = parent->secondary;
unsigned char end = parent->subordinate;
for (busnr = start; busnr <= end; busnr++) {
if (!pci_find_bus(pci_domain_nr(parent),
busnr))
break;
}
if (busnr >= end) {
err("No free bus for hot-added bridge\n");
continue;
}
child = pci_add_new_bus(parent, dev, busnr);
if (!child) {
err("Cannot add new bus for %s\n",
pci_name(dev));
continue;
}
child->subordinate = pci_do_scan_bus(child);
pci_bus_size_bridges(child);
}
program_fw_provided_values(dev);
}
pci_bus_assign_resources(parent);
pci_bus_add_devices(parent);
pci_enable_bridges(parent);
return 0;
}
int shpchp_unconfigure_device(struct pci_func* func)
{
int rc = 0;
int j;
dbg("%s: bus/dev/func = %x/%x/%x\n", __FUNCTION__, func->bus,
func->device, func->function);
for (j=0; j<8 ; j++) {
struct pci_dev* temp = pci_find_slot(func->bus,
(func->device << 3) | j);
if (temp) {
pci_remove_bus_device(temp);
}
}
return rc;
}
/* More PCI configuration routines; this time centered around hotplug controller */
/*
* shpchp_save_config
*
* Reads configuration for all slots in a PCI bus and saves info.
*
* Note: For non-hot plug busses, the slot # saved is the device #
*
* returns 0 if success
*/
int shpchp_save_config(struct controller *ctrl, int busnumber, int num_ctlr_slots, int first_device_num)
{
int rc;
u8 class_code;
u8 header_type;
u32 ID;
u8 secondary_bus;
struct pci_func *new_slot;
int sub_bus;
int FirstSupported;
int LastSupported;
int max_functions;
int function;
u8 DevError;
int device = 0;
int cloop = 0;
int stop_it;
int index;
int is_hot_plug = num_ctlr_slots || first_device_num;
struct pci_bus lpci_bus, *pci_bus;
dbg("%s: num_ctlr_slots = %d, first_device_num = %d\n", __FUNCTION__,
num_ctlr_slots, first_device_num);
memcpy(&lpci_bus, ctrl->pci_dev->subordinate, sizeof(lpci_bus));
pci_bus = &lpci_bus;
dbg("%s: num_ctlr_slots = %d, first_device_num = %d\n", __FUNCTION__,
num_ctlr_slots, first_device_num);
/* Decide which slots are supported */
if (is_hot_plug) {
/*********************************
* is_hot_plug is the slot mask
*********************************/
FirstSupported = first_device_num;
LastSupported = FirstSupported + num_ctlr_slots - 1;
} else {
FirstSupported = 0;
LastSupported = 0x1F;
}
dbg("FirstSupported = %d, LastSupported = %d\n", FirstSupported,
LastSupported);
/* Save PCI configuration space for all devices in supported slots */
pci_bus->number = busnumber;
for (device = FirstSupported; device <= LastSupported; device++) {
ID = 0xFFFFFFFF;
rc = pci_bus_read_config_dword(pci_bus, PCI_DEVFN(device, 0),
PCI_VENDOR_ID, &ID);
if (ID != 0xFFFFFFFF) { /* device in slot */
rc = pci_bus_read_config_byte(pci_bus, PCI_DEVFN(device, 0),
0x0B, &class_code);
if (rc)
return rc;
rc = pci_bus_read_config_byte(pci_bus, PCI_DEVFN(device, 0),
PCI_HEADER_TYPE, &header_type);
if (rc)
return rc;
dbg("class_code = %x, header_type = %x\n", class_code, header_type);
/* If multi-function device, set max_functions to 8 */
if (header_type & 0x80)
max_functions = 8;
else
max_functions = 1;
function = 0;
do {
DevError = 0;
if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) { /* P-P Bridge */
/* Recurse the subordinate bus
* get the subordinate bus number
*/
rc = pci_bus_read_config_byte(pci_bus,
PCI_DEVFN(device, function),
PCI_SECONDARY_BUS, &secondary_bus);
if (rc) {
return rc;
} else {
sub_bus = (int) secondary_bus;
/* Save secondary bus cfg spc with this recursive call. */
rc = shpchp_save_config(ctrl, sub_bus, 0, 0);
if (rc)
return rc;
}
}
index = 0;
new_slot = shpchp_slot_find(busnumber, device, index++);
dbg("new_slot = %p\n", new_slot);
while (new_slot && (new_slot->function != (u8) function)) {
new_slot = shpchp_slot_find(busnumber, device, index++);
dbg("new_slot = %p\n", new_slot);
}
if (!new_slot) {
/* Setup slot structure. */
new_slot = shpchp_slot_create(busnumber);
dbg("new_slot = %p\n", new_slot);
if (new_slot == NULL)
return(1);
}
new_slot->bus = (u8) busnumber;
new_slot->device = (u8) device;
new_slot->function = (u8) function;
new_slot->is_a_board = 1;
new_slot->switch_save = 0x10;
new_slot->pwr_save = 1;
/* In case of unsupported board */
new_slot->status = DevError;
new_slot->pci_dev = pci_find_slot(new_slot->bus,
(new_slot->device << 3) | new_slot->function);
dbg("new_slot->pci_dev = %p\n", new_slot->pci_dev);
for (cloop = 0; cloop < 0x20; cloop++) {
rc = pci_bus_read_config_dword(pci_bus,
PCI_DEVFN(device, function),
cloop << 2,
(u32 *) &(new_slot->config_space [cloop]));
/* dbg("new_slot->config_space[%x] = %x\n",
cloop, new_slot->config_space[cloop]); */
if (rc)
return rc;
}
function++;
stop_it = 0;
/* this loop skips to the next present function
* reading in Class Code and Header type.
*/
while ((function < max_functions)&&(!stop_it)) {
rc = pci_bus_read_config_dword(pci_bus,
PCI_DEVFN(device, function),
PCI_VENDOR_ID, &ID);
if (ID == 0xFFFFFFFF) { /* nothing there. */
function++;
dbg("Nothing there\n");
} else { /* Something there */
rc = pci_bus_read_config_byte(pci_bus,
PCI_DEVFN(device, function),
0x0B, &class_code);
if (rc)
return rc;
rc = pci_bus_read_config_byte(pci_bus,
PCI_DEVFN(device, function),
PCI_HEADER_TYPE, &header_type);
if (rc)
return rc;
dbg("class_code = %x, header_type = %x\n",
class_code, header_type);
stop_it++;
}
}
} while (function < max_functions);
/* End of IF (device in slot?) */
} else if (is_hot_plug) {
/* Setup slot structure with entry for empty slot */
new_slot = shpchp_slot_create(busnumber);
if (new_slot == NULL) {
return(1);
}
dbg("new_slot = %p\n", new_slot);
new_slot->bus = (u8) busnumber;
new_slot->device = (u8) device;
new_slot->function = 0;
new_slot->is_a_board = 0;
new_slot->presence_save = 0;
new_slot->switch_save = 0;
}
} /* End of FOR loop */
return(0);
}
/*
* shpchp_save_slot_config
*
* Saves configuration info for all PCI devices in a given slot
* including subordinate busses.
*
* returns 0 if success
*/
int shpchp_save_slot_config(struct controller *ctrl, struct pci_func * new_slot)
{
int rc;
u8 class_code;
u8 header_type;
u32 ID;
u8 secondary_bus;
int sub_bus;
int max_functions;
int function;
int cloop = 0;
int stop_it;
struct pci_bus lpci_bus, *pci_bus;
memcpy(&lpci_bus, ctrl->pci_dev->subordinate, sizeof(lpci_bus));
pci_bus = &lpci_bus;
pci_bus->number = new_slot->bus;
ID = 0xFFFFFFFF;
pci_bus_read_config_dword(pci_bus, PCI_DEVFN(new_slot->device, 0),
PCI_VENDOR_ID, &ID);
if (ID != 0xFFFFFFFF) { /* device in slot */
pci_bus_read_config_byte(pci_bus, PCI_DEVFN(new_slot->device, 0),
0x0B, &class_code);
pci_bus_read_config_byte(pci_bus, PCI_DEVFN(new_slot->device, 0),
PCI_HEADER_TYPE, &header_type);
if (header_type & 0x80) /* Multi-function device */
max_functions = 8;
else
max_functions = 1;
function = 0;
do {
if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) { /* PCI-PCI Bridge */
/* Recurse the subordinate bus */
pci_bus_read_config_byte(pci_bus,
PCI_DEVFN(new_slot->device, function),
PCI_SECONDARY_BUS, &secondary_bus);
sub_bus = (int) secondary_bus;
/* Save the config headers for the secondary bus. */
rc = shpchp_save_config(ctrl, sub_bus, 0, 0);
if (rc)
return rc;
} /* End of IF */
new_slot->status = 0;
for (cloop = 0; cloop < 0x20; cloop++) {
pci_bus_read_config_dword(pci_bus,
PCI_DEVFN(new_slot->device, function),
cloop << 2,
(u32 *) &(new_slot->config_space [cloop]));
}
function++;
stop_it = 0;
/* this loop skips to the next present function
* reading in the Class Code and the Header type.
*/
while ((function < max_functions) && (!stop_it)) {
pci_bus_read_config_dword(pci_bus,
PCI_DEVFN(new_slot->device, function),
PCI_VENDOR_ID, &ID);
if (ID == 0xFFFFFFFF) { /* nothing there. */
function++;
} else { /* Something there */
pci_bus_read_config_byte(pci_bus,
PCI_DEVFN(new_slot->device, function),
0x0B, &class_code);
pci_bus_read_config_byte(pci_bus,
PCI_DEVFN(new_slot->device, function),
PCI_HEADER_TYPE, &header_type);
stop_it++;
}
}
} while (function < max_functions);
} /* End of IF (device in slot?) */
else {
return 2;
}
return 0;
}