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linux/drivers/pci/hotplug/acpi_pcihp.c
Rafael J. Wysocki 28eb5f274a PCI: PCIe: Ask BIOS for control of all native services at once
After commit 852972acff (ACPI: Disable
ASPM if the platform won't provide _OSC control for PCIe) control of
the PCIe Capability Structure is unconditionally requested by
acpi_pci_root_add(), which in principle may cause problems to
happen in two ways.  First, the BIOS may refuse to give control of
the PCIe Capability Structure if it is not asked for any of the
_OSC features depending on it at the same time.  Second, the BIOS may
assume that control of the _OSC features depending on the PCIe
Capability Structure will be requested in the future and may behave
incorrectly if that doesn't happen.  For this reason, control of
the PCIe Capability Structure should always be requested along with
control of any other _OSC features that may depend on it (ie. PCIe
native PME, PCIe native hot-plug, PCIe AER).

Rework the PCIe port driver so that (1) it checks which native PCIe
port services can be enabled, according to the BIOS, and (2) it
requests control of all these services simultaneously.  In
particular, this causes pcie_portdrv_probe() to fail if the BIOS
refuses to grant control of the PCIe Capability Structure, which
means that no native PCIe port services can be enabled for the PCIe
Root Complex the given port belongs to.  If that happens, ASPM is
disabled to avoid problems with mishandling it by the part of the
PCIe hierarchy for which control of the PCIe Capability Structure
has not been received.

Make it possible to override this behavior using 'pcie_ports=native'
(use the PCIe native services regardless of the BIOS response to the
control request), or 'pcie_ports=compat' (do not use the PCIe native
services at all).

Accordingly, rework the existing PCIe port service drivers so that
they don't request control of the services directly.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
2010-08-24 13:47:33 -07:00

481 lines
13 KiB
C

/*
* Common ACPI functions for hot plug platforms
*
* Copyright (C) 2006 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 <kristen.c.accardi@intel.com>
*
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/pci.h>
#include <linux/pci_hotplug.h>
#include <linux/acpi.h>
#include <linux/pci-acpi.h>
#include <linux/slab.h>
#define MY_NAME "acpi_pcihp"
#define dbg(fmt, arg...) do { if (debug_acpi) printk(KERN_DEBUG "%s: %s: " fmt , MY_NAME , __func__ , ## arg); } while (0)
#define err(format, arg...) printk(KERN_ERR "%s: " format , MY_NAME , ## arg)
#define info(format, arg...) printk(KERN_INFO "%s: " format , MY_NAME , ## arg)
#define warn(format, arg...) printk(KERN_WARNING "%s: " format , MY_NAME , ## arg)
#define METHOD_NAME__SUN "_SUN"
#define METHOD_NAME_OSHP "OSHP"
static int debug_acpi;
static acpi_status
decode_type0_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
{
int i;
union acpi_object *fields = record->package.elements;
u32 revision = fields[1].integer.value;
switch (revision) {
case 1:
if (record->package.count != 6)
return AE_ERROR;
for (i = 2; i < 6; i++)
if (fields[i].type != ACPI_TYPE_INTEGER)
return AE_ERROR;
hpx->t0 = &hpx->type0_data;
hpx->t0->revision = revision;
hpx->t0->cache_line_size = fields[2].integer.value;
hpx->t0->latency_timer = fields[3].integer.value;
hpx->t0->enable_serr = fields[4].integer.value;
hpx->t0->enable_perr = fields[5].integer.value;
break;
default:
printk(KERN_WARNING
"%s: Type 0 Revision %d record not supported\n",
__func__, revision);
return AE_ERROR;
}
return AE_OK;
}
static acpi_status
decode_type1_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
{
int i;
union acpi_object *fields = record->package.elements;
u32 revision = fields[1].integer.value;
switch (revision) {
case 1:
if (record->package.count != 5)
return AE_ERROR;
for (i = 2; i < 5; i++)
if (fields[i].type != ACPI_TYPE_INTEGER)
return AE_ERROR;
hpx->t1 = &hpx->type1_data;
hpx->t1->revision = revision;
hpx->t1->max_mem_read = fields[2].integer.value;
hpx->t1->avg_max_split = fields[3].integer.value;
hpx->t1->tot_max_split = fields[4].integer.value;
break;
default:
printk(KERN_WARNING
"%s: Type 1 Revision %d record not supported\n",
__func__, revision);
return AE_ERROR;
}
return AE_OK;
}
static acpi_status
decode_type2_hpx_record(union acpi_object *record, struct hotplug_params *hpx)
{
int i;
union acpi_object *fields = record->package.elements;
u32 revision = fields[1].integer.value;
switch (revision) {
case 1:
if (record->package.count != 18)
return AE_ERROR;
for (i = 2; i < 18; i++)
if (fields[i].type != ACPI_TYPE_INTEGER)
return AE_ERROR;
hpx->t2 = &hpx->type2_data;
hpx->t2->revision = revision;
hpx->t2->unc_err_mask_and = fields[2].integer.value;
hpx->t2->unc_err_mask_or = fields[3].integer.value;
hpx->t2->unc_err_sever_and = fields[4].integer.value;
hpx->t2->unc_err_sever_or = fields[5].integer.value;
hpx->t2->cor_err_mask_and = fields[6].integer.value;
hpx->t2->cor_err_mask_or = fields[7].integer.value;
hpx->t2->adv_err_cap_and = fields[8].integer.value;
hpx->t2->adv_err_cap_or = fields[9].integer.value;
hpx->t2->pci_exp_devctl_and = fields[10].integer.value;
hpx->t2->pci_exp_devctl_or = fields[11].integer.value;
hpx->t2->pci_exp_lnkctl_and = fields[12].integer.value;
hpx->t2->pci_exp_lnkctl_or = fields[13].integer.value;
hpx->t2->sec_unc_err_sever_and = fields[14].integer.value;
hpx->t2->sec_unc_err_sever_or = fields[15].integer.value;
hpx->t2->sec_unc_err_mask_and = fields[16].integer.value;
hpx->t2->sec_unc_err_mask_or = fields[17].integer.value;
break;
default:
printk(KERN_WARNING
"%s: Type 2 Revision %d record not supported\n",
__func__, revision);
return AE_ERROR;
}
return AE_OK;
}
static acpi_status
acpi_run_hpx(acpi_handle handle, struct hotplug_params *hpx)
{
acpi_status status;
struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
union acpi_object *package, *record, *fields;
u32 type;
int i;
/* Clear the return buffer with zeros */
memset(hpx, 0, sizeof(struct hotplug_params));
status = acpi_evaluate_object(handle, "_HPX", NULL, &buffer);
if (ACPI_FAILURE(status))
return status;
package = (union acpi_object *)buffer.pointer;
if (package->type != ACPI_TYPE_PACKAGE) {
status = AE_ERROR;
goto exit;
}
for (i = 0; i < package->package.count; i++) {
record = &package->package.elements[i];
if (record->type != ACPI_TYPE_PACKAGE) {
status = AE_ERROR;
goto exit;
}
fields = record->package.elements;
if (fields[0].type != ACPI_TYPE_INTEGER ||
fields[1].type != ACPI_TYPE_INTEGER) {
status = AE_ERROR;
goto exit;
}
type = fields[0].integer.value;
switch (type) {
case 0:
status = decode_type0_hpx_record(record, hpx);
if (ACPI_FAILURE(status))
goto exit;
break;
case 1:
status = decode_type1_hpx_record(record, hpx);
if (ACPI_FAILURE(status))
goto exit;
break;
case 2:
status = decode_type2_hpx_record(record, hpx);
if (ACPI_FAILURE(status))
goto exit;
break;
default:
printk(KERN_ERR "%s: Type %d record not supported\n",
__func__, type);
status = AE_ERROR;
goto exit;
}
}
exit:
kfree(buffer.pointer);
return status;
}
static acpi_status
acpi_run_hpp(acpi_handle handle, struct hotplug_params *hpp)
{
acpi_status status;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *package, *fields;
int i;
memset(hpp, 0, sizeof(struct hotplug_params));
status = acpi_evaluate_object(handle, "_HPP", NULL, &buffer);
if (ACPI_FAILURE(status))
return status;
package = (union acpi_object *) buffer.pointer;
if (package->type != ACPI_TYPE_PACKAGE ||
package->package.count != 4) {
status = AE_ERROR;
goto exit;
}
fields = package->package.elements;
for (i = 0; i < 4; i++) {
if (fields[i].type != ACPI_TYPE_INTEGER) {
status = AE_ERROR;
goto exit;
}
}
hpp->t0 = &hpp->type0_data;
hpp->t0->revision = 1;
hpp->t0->cache_line_size = fields[0].integer.value;
hpp->t0->latency_timer = fields[1].integer.value;
hpp->t0->enable_serr = fields[2].integer.value;
hpp->t0->enable_perr = fields[3].integer.value;
exit:
kfree(buffer.pointer);
return status;
}
/* acpi_run_oshp - get control of hotplug from the firmware
*
* @handle - the handle of the hotplug controller.
*/
static acpi_status acpi_run_oshp(acpi_handle handle)
{
acpi_status status;
struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };
acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
/* run OSHP */
status = acpi_evaluate_object(handle, METHOD_NAME_OSHP, NULL, NULL);
if (ACPI_FAILURE(status))
if (status != AE_NOT_FOUND)
printk(KERN_ERR "%s:%s OSHP fails=0x%x\n",
__func__, (char *)string.pointer, status);
else
dbg("%s:%s OSHP not found\n",
__func__, (char *)string.pointer);
else
pr_debug("%s:%s OSHP passes\n", __func__,
(char *)string.pointer);
kfree(string.pointer);
return status;
}
/* pci_get_hp_params
*
* @dev - the pci_dev for which we want parameters
* @hpp - allocated by the caller
*/
int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp)
{
acpi_status status;
acpi_handle handle, phandle;
struct pci_bus *pbus;
handle = NULL;
for (pbus = dev->bus; pbus; pbus = pbus->parent) {
handle = acpi_pci_get_bridge_handle(pbus);
if (handle)
break;
}
/*
* _HPP settings apply to all child buses, until another _HPP is
* encountered. If we don't find an _HPP for the input pci dev,
* look for it in the parent device scope since that would apply to
* this pci dev.
*/
while (handle) {
status = acpi_run_hpx(handle, hpp);
if (ACPI_SUCCESS(status))
return 0;
status = acpi_run_hpp(handle, hpp);
if (ACPI_SUCCESS(status))
return 0;
if (acpi_is_root_bridge(handle))
break;
status = acpi_get_parent(handle, &phandle);
if (ACPI_FAILURE(status))
break;
handle = phandle;
}
return -ENODEV;
}
EXPORT_SYMBOL_GPL(pci_get_hp_params);
/**
* acpi_get_hp_hw_control_from_firmware
* @dev: the pci_dev of the bridge that has a hotplug controller
* @flags: requested control bits for _OSC
*
* Attempt to take hotplug control from firmware.
*/
int acpi_get_hp_hw_control_from_firmware(struct pci_dev *pdev, u32 flags)
{
acpi_status status;
acpi_handle chandle, handle;
struct acpi_buffer string = { ACPI_ALLOCATE_BUFFER, NULL };
flags &= OSC_SHPC_NATIVE_HP_CONTROL;
if (!flags) {
err("Invalid flags %u specified!\n", flags);
return -EINVAL;
}
/*
* Per PCI firmware specification, we should run the ACPI _OSC
* method to get control of hotplug hardware before using it. If
* an _OSC is missing, we look for an OSHP to do the same thing.
* To handle different BIOS behavior, we look for _OSC on a root
* bridge preferentially (according to PCI fw spec). Later for
* OSHP within the scope of the hotplug controller and its parents,
* upto the host bridge under which this controller exists.
*/
handle = acpi_find_root_bridge_handle(pdev);
if (handle) {
acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
dbg("Trying to get hotplug control for %s\n",
(char *)string.pointer);
status = acpi_pci_osc_control_set(handle, &flags, flags);
if (ACPI_SUCCESS(status))
goto got_one;
if (status == AE_SUPPORT)
goto no_control;
kfree(string.pointer);
string = (struct acpi_buffer){ ACPI_ALLOCATE_BUFFER, NULL };
}
handle = DEVICE_ACPI_HANDLE(&pdev->dev);
if (!handle) {
/*
* This hotplug controller was not listed in the ACPI name
* space at all. Try to get acpi handle of parent pci bus.
*/
struct pci_bus *pbus;
for (pbus = pdev->bus; pbus; pbus = pbus->parent) {
handle = acpi_pci_get_bridge_handle(pbus);
if (handle)
break;
}
}
while (handle) {
acpi_get_name(handle, ACPI_FULL_PATHNAME, &string);
dbg("Trying to get hotplug control for %s \n",
(char *)string.pointer);
status = acpi_run_oshp(handle);
if (ACPI_SUCCESS(status))
goto got_one;
if (acpi_is_root_bridge(handle))
break;
chandle = handle;
status = acpi_get_parent(chandle, &handle);
if (ACPI_FAILURE(status))
break;
}
no_control:
dbg("Cannot get control of hotplug hardware for pci %s\n",
pci_name(pdev));
kfree(string.pointer);
return -ENODEV;
got_one:
dbg("Gained control for hotplug HW for pci %s (%s)\n",
pci_name(pdev), (char *)string.pointer);
kfree(string.pointer);
return 0;
}
EXPORT_SYMBOL(acpi_get_hp_hw_control_from_firmware);
static int is_ejectable(acpi_handle handle)
{
acpi_status status;
acpi_handle tmp;
unsigned long long removable;
status = acpi_get_handle(handle, "_ADR", &tmp);
if (ACPI_FAILURE(status))
return 0;
status = acpi_get_handle(handle, "_EJ0", &tmp);
if (ACPI_SUCCESS(status))
return 1;
status = acpi_evaluate_integer(handle, "_RMV", NULL, &removable);
if (ACPI_SUCCESS(status) && removable)
return 1;
return 0;
}
/**
* acpi_pcihp_check_ejectable - check if handle is ejectable ACPI PCI slot
* @pbus: the PCI bus of the PCI slot corresponding to 'handle'
* @handle: ACPI handle to check
*
* Return 1 if handle is ejectable PCI slot, 0 otherwise.
*/
int acpi_pci_check_ejectable(struct pci_bus *pbus, acpi_handle handle)
{
acpi_handle bridge_handle, parent_handle;
if (!(bridge_handle = acpi_pci_get_bridge_handle(pbus)))
return 0;
if ((ACPI_FAILURE(acpi_get_parent(handle, &parent_handle))))
return 0;
if (bridge_handle != parent_handle)
return 0;
return is_ejectable(handle);
}
EXPORT_SYMBOL_GPL(acpi_pci_check_ejectable);
static acpi_status
check_hotplug(acpi_handle handle, u32 lvl, void *context, void **rv)
{
int *found = (int *)context;
if (is_ejectable(handle)) {
*found = 1;
return AE_CTRL_TERMINATE;
}
return AE_OK;
}
/**
* acpi_pci_detect_ejectable - check if the PCI bus has ejectable slots
* @handle - handle of the PCI bus to scan
*
* Returns 1 if the PCI bus has ACPI based ejectable slots, 0 otherwise.
*/
int acpi_pci_detect_ejectable(acpi_handle handle)
{
int found = 0;
if (!handle)
return found;
acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
check_hotplug, NULL, (void *)&found, NULL);
return found;
}
EXPORT_SYMBOL_GPL(acpi_pci_detect_ejectable);
module_param(debug_acpi, bool, 0644);
MODULE_PARM_DESC(debug_acpi, "Debugging mode for ACPI enabled or not");