kernel_optimize_test/drivers/pci/pci.c
Eric W. Biederman 392ee1e6dd [PATCH] msi: Safer state caching.
There are two ways pci_save_state and pci_restore_state are used.  As
helper functions during suspend/resume, and as helper functions around
a hardware reset event.  When used as helper functions around a hardware
reset event there is no reason to believe the calls will be paired, nor
is there a good reason to believe that if we restore the msi state from
before the reset that it will match the current msi state.  Since arch
code may change the msi message without going through the driver, drivers
currently do not have enough information to even know when to call
pci_save_state to ensure they will have msi state in sync with the other
kernel irq reception data structures.

It turns out the solution is straight forward, cache the state in the
existing msi data structures (not the magic pci saved things) and
have the msi code update the cached state each time we write to the hardware.
This means we never need to read the hardware to figure out what the hardware
state should be.

By modifying the caching in this manner we get to remove our save_state
routines and only need to provide restore_state routines.

The only fields that were at all tricky to regenerate were the msi and msi-x
control registers and the way we regenerate them currently is a bit dependent
upon assumptions on how we use the allow msi registers to be configured and used
making the code a little bit brittle.  If we ever change what cases we allow
or how we configure the msi bits we can address the fragility then.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-12 16:31:50 -07:00

1407 lines
36 KiB
C

/*
* $Id: pci.c,v 1.91 1999/01/21 13:34:01 davem Exp $
*
* PCI Bus Services, see include/linux/pci.h for further explanation.
*
* Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter,
* David Mosberger-Tang
*
* Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>
*/
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <asm/dma.h> /* isa_dma_bridge_buggy */
#include "pci.h"
unsigned int pci_pm_d3_delay = 10;
#define DEFAULT_CARDBUS_IO_SIZE (256)
#define DEFAULT_CARDBUS_MEM_SIZE (64*1024*1024)
/* pci=cbmemsize=nnM,cbiosize=nn can override this */
unsigned long pci_cardbus_io_size = DEFAULT_CARDBUS_IO_SIZE;
unsigned long pci_cardbus_mem_size = DEFAULT_CARDBUS_MEM_SIZE;
/**
* pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
* @bus: pointer to PCI bus structure to search
*
* Given a PCI bus, returns the highest PCI bus number present in the set
* including the given PCI bus and its list of child PCI buses.
*/
unsigned char __devinit
pci_bus_max_busnr(struct pci_bus* bus)
{
struct list_head *tmp;
unsigned char max, n;
max = bus->subordinate;
list_for_each(tmp, &bus->children) {
n = pci_bus_max_busnr(pci_bus_b(tmp));
if(n > max)
max = n;
}
return max;
}
EXPORT_SYMBOL_GPL(pci_bus_max_busnr);
#if 0
/**
* pci_max_busnr - returns maximum PCI bus number
*
* Returns the highest PCI bus number present in the system global list of
* PCI buses.
*/
unsigned char __devinit
pci_max_busnr(void)
{
struct pci_bus *bus = NULL;
unsigned char max, n;
max = 0;
while ((bus = pci_find_next_bus(bus)) != NULL) {
n = pci_bus_max_busnr(bus);
if(n > max)
max = n;
}
return max;
}
#endif /* 0 */
#define PCI_FIND_CAP_TTL 48
static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
u8 pos, int cap, int *ttl)
{
u8 id;
while ((*ttl)--) {
pci_bus_read_config_byte(bus, devfn, pos, &pos);
if (pos < 0x40)
break;
pos &= ~3;
pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
&id);
if (id == 0xff)
break;
if (id == cap)
return pos;
pos += PCI_CAP_LIST_NEXT;
}
return 0;
}
static int __pci_find_next_cap(struct pci_bus *bus, unsigned int devfn,
u8 pos, int cap)
{
int ttl = PCI_FIND_CAP_TTL;
return __pci_find_next_cap_ttl(bus, devfn, pos, cap, &ttl);
}
int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap)
{
return __pci_find_next_cap(dev->bus, dev->devfn,
pos + PCI_CAP_LIST_NEXT, cap);
}
EXPORT_SYMBOL_GPL(pci_find_next_capability);
static int __pci_bus_find_cap_start(struct pci_bus *bus,
unsigned int devfn, u8 hdr_type)
{
u16 status;
pci_bus_read_config_word(bus, devfn, PCI_STATUS, &status);
if (!(status & PCI_STATUS_CAP_LIST))
return 0;
switch (hdr_type) {
case PCI_HEADER_TYPE_NORMAL:
case PCI_HEADER_TYPE_BRIDGE:
return PCI_CAPABILITY_LIST;
case PCI_HEADER_TYPE_CARDBUS:
return PCI_CB_CAPABILITY_LIST;
default:
return 0;
}
return 0;
}
/**
* pci_find_capability - query for devices' capabilities
* @dev: PCI device to query
* @cap: capability code
*
* Tell if a device supports a given PCI capability.
* Returns the address of the requested capability structure within the
* device's PCI configuration space or 0 in case the device does not
* support it. Possible values for @cap:
*
* %PCI_CAP_ID_PM Power Management
* %PCI_CAP_ID_AGP Accelerated Graphics Port
* %PCI_CAP_ID_VPD Vital Product Data
* %PCI_CAP_ID_SLOTID Slot Identification
* %PCI_CAP_ID_MSI Message Signalled Interrupts
* %PCI_CAP_ID_CHSWP CompactPCI HotSwap
* %PCI_CAP_ID_PCIX PCI-X
* %PCI_CAP_ID_EXP PCI Express
*/
int pci_find_capability(struct pci_dev *dev, int cap)
{
int pos;
pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
if (pos)
pos = __pci_find_next_cap(dev->bus, dev->devfn, pos, cap);
return pos;
}
/**
* pci_bus_find_capability - query for devices' capabilities
* @bus: the PCI bus to query
* @devfn: PCI device to query
* @cap: capability code
*
* Like pci_find_capability() but works for pci devices that do not have a
* pci_dev structure set up yet.
*
* Returns the address of the requested capability structure within the
* device's PCI configuration space or 0 in case the device does not
* support it.
*/
int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
{
int pos;
u8 hdr_type;
pci_bus_read_config_byte(bus, devfn, PCI_HEADER_TYPE, &hdr_type);
pos = __pci_bus_find_cap_start(bus, devfn, hdr_type & 0x7f);
if (pos)
pos = __pci_find_next_cap(bus, devfn, pos, cap);
return pos;
}
/**
* pci_find_ext_capability - Find an extended capability
* @dev: PCI device to query
* @cap: capability code
*
* Returns the address of the requested extended capability structure
* within the device's PCI configuration space or 0 if the device does
* not support it. Possible values for @cap:
*
* %PCI_EXT_CAP_ID_ERR Advanced Error Reporting
* %PCI_EXT_CAP_ID_VC Virtual Channel
* %PCI_EXT_CAP_ID_DSN Device Serial Number
* %PCI_EXT_CAP_ID_PWR Power Budgeting
*/
int pci_find_ext_capability(struct pci_dev *dev, int cap)
{
u32 header;
int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
int pos = 0x100;
if (dev->cfg_size <= 256)
return 0;
if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
return 0;
/*
* If we have no capabilities, this is indicated by cap ID,
* cap version and next pointer all being 0.
*/
if (header == 0)
return 0;
while (ttl-- > 0) {
if (PCI_EXT_CAP_ID(header) == cap)
return pos;
pos = PCI_EXT_CAP_NEXT(header);
if (pos < 0x100)
break;
if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
break;
}
return 0;
}
EXPORT_SYMBOL_GPL(pci_find_ext_capability);
static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap)
{
int rc, ttl = PCI_FIND_CAP_TTL;
u8 cap, mask;
if (ht_cap == HT_CAPTYPE_SLAVE || ht_cap == HT_CAPTYPE_HOST)
mask = HT_3BIT_CAP_MASK;
else
mask = HT_5BIT_CAP_MASK;
pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn, pos,
PCI_CAP_ID_HT, &ttl);
while (pos) {
rc = pci_read_config_byte(dev, pos + 3, &cap);
if (rc != PCIBIOS_SUCCESSFUL)
return 0;
if ((cap & mask) == ht_cap)
return pos;
pos = __pci_find_next_cap_ttl(dev->bus, dev->devfn,
pos + PCI_CAP_LIST_NEXT,
PCI_CAP_ID_HT, &ttl);
}
return 0;
}
/**
* pci_find_next_ht_capability - query a device's Hypertransport capabilities
* @dev: PCI device to query
* @pos: Position from which to continue searching
* @ht_cap: Hypertransport capability code
*
* To be used in conjunction with pci_find_ht_capability() to search for
* all capabilities matching @ht_cap. @pos should always be a value returned
* from pci_find_ht_capability().
*
* NB. To be 100% safe against broken PCI devices, the caller should take
* steps to avoid an infinite loop.
*/
int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap)
{
return __pci_find_next_ht_cap(dev, pos + PCI_CAP_LIST_NEXT, ht_cap);
}
EXPORT_SYMBOL_GPL(pci_find_next_ht_capability);
/**
* pci_find_ht_capability - query a device's Hypertransport capabilities
* @dev: PCI device to query
* @ht_cap: Hypertransport capability code
*
* Tell if a device supports a given Hypertransport capability.
* Returns an address within the device's PCI configuration space
* or 0 in case the device does not support the request capability.
* The address points to the PCI capability, of type PCI_CAP_ID_HT,
* which has a Hypertransport capability matching @ht_cap.
*/
int pci_find_ht_capability(struct pci_dev *dev, int ht_cap)
{
int pos;
pos = __pci_bus_find_cap_start(dev->bus, dev->devfn, dev->hdr_type);
if (pos)
pos = __pci_find_next_ht_cap(dev, pos, ht_cap);
return pos;
}
EXPORT_SYMBOL_GPL(pci_find_ht_capability);
/**
* pci_find_parent_resource - return resource region of parent bus of given region
* @dev: PCI device structure contains resources to be searched
* @res: child resource record for which parent is sought
*
* For given resource region of given device, return the resource
* region of parent bus the given region is contained in or where
* it should be allocated from.
*/
struct resource *
pci_find_parent_resource(const struct pci_dev *dev, struct resource *res)
{
const struct pci_bus *bus = dev->bus;
int i;
struct resource *best = NULL;
for(i = 0; i < PCI_BUS_NUM_RESOURCES; i++) {
struct resource *r = bus->resource[i];
if (!r)
continue;
if (res->start && !(res->start >= r->start && res->end <= r->end))
continue; /* Not contained */
if ((res->flags ^ r->flags) & (IORESOURCE_IO | IORESOURCE_MEM))
continue; /* Wrong type */
if (!((res->flags ^ r->flags) & IORESOURCE_PREFETCH))
return r; /* Exact match */
if ((res->flags & IORESOURCE_PREFETCH) && !(r->flags & IORESOURCE_PREFETCH))
best = r; /* Approximating prefetchable by non-prefetchable */
}
return best;
}
/**
* pci_restore_bars - restore a devices BAR values (e.g. after wake-up)
* @dev: PCI device to have its BARs restored
*
* Restore the BAR values for a given device, so as to make it
* accessible by its driver.
*/
void
pci_restore_bars(struct pci_dev *dev)
{
int i, numres;
switch (dev->hdr_type) {
case PCI_HEADER_TYPE_NORMAL:
numres = 6;
break;
case PCI_HEADER_TYPE_BRIDGE:
numres = 2;
break;
case PCI_HEADER_TYPE_CARDBUS:
numres = 1;
break;
default:
/* Should never get here, but just in case... */
return;
}
for (i = 0; i < numres; i ++)
pci_update_resource(dev, &dev->resource[i], i);
}
int (*platform_pci_set_power_state)(struct pci_dev *dev, pci_power_t t);
/**
* pci_set_power_state - Set the power state of a PCI device
* @dev: PCI device to be suspended
* @state: PCI power state (D0, D1, D2, D3hot, D3cold) we're entering
*
* Transition a device to a new power state, using the Power Management
* Capabilities in the device's config space.
*
* RETURN VALUE:
* -EINVAL if trying to enter a lower state than we're already in.
* 0 if we're already in the requested state.
* -EIO if device does not support PCI PM.
* 0 if we can successfully change the power state.
*/
int
pci_set_power_state(struct pci_dev *dev, pci_power_t state)
{
int pm, need_restore = 0;
u16 pmcsr, pmc;
/* bound the state we're entering */
if (state > PCI_D3hot)
state = PCI_D3hot;
/*
* If the device or the parent bridge can't support PCI PM, ignore
* the request if we're doing anything besides putting it into D0
* (which would only happen on boot).
*/
if ((state == PCI_D1 || state == PCI_D2) && pci_no_d1d2(dev))
return 0;
/* Validate current state:
* Can enter D0 from any state, but if we can only go deeper
* to sleep if we're already in a low power state
*/
if (state != PCI_D0 && dev->current_state > state) {
printk(KERN_ERR "%s(): %s: state=%d, current state=%d\n",
__FUNCTION__, pci_name(dev), state, dev->current_state);
return -EINVAL;
} else if (dev->current_state == state)
return 0; /* we're already there */
/* find PCI PM capability in list */
pm = pci_find_capability(dev, PCI_CAP_ID_PM);
/* abort if the device doesn't support PM capabilities */
if (!pm)
return -EIO;
pci_read_config_word(dev,pm + PCI_PM_PMC,&pmc);
if ((pmc & PCI_PM_CAP_VER_MASK) > 3) {
printk(KERN_DEBUG
"PCI: %s has unsupported PM cap regs version (%u)\n",
pci_name(dev), pmc & PCI_PM_CAP_VER_MASK);
return -EIO;
}
/* check if this device supports the desired state */
if (state == PCI_D1 && !(pmc & PCI_PM_CAP_D1))
return -EIO;
else if (state == PCI_D2 && !(pmc & PCI_PM_CAP_D2))
return -EIO;
pci_read_config_word(dev, pm + PCI_PM_CTRL, &pmcsr);
/* If we're (effectively) in D3, force entire word to 0.
* This doesn't affect PME_Status, disables PME_En, and
* sets PowerState to 0.
*/
switch (dev->current_state) {
case PCI_D0:
case PCI_D1:
case PCI_D2:
pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
pmcsr |= state;
break;
case PCI_UNKNOWN: /* Boot-up */
if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
&& !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
need_restore = 1;
/* Fall-through: force to D0 */
default:
pmcsr = 0;
break;
}
/* enter specified state */
pci_write_config_word(dev, pm + PCI_PM_CTRL, pmcsr);
/* Mandatory power management transition delays */
/* see PCI PM 1.1 5.6.1 table 18 */
if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
msleep(pci_pm_d3_delay);
else if (state == PCI_D2 || dev->current_state == PCI_D2)
udelay(200);
/*
* Give firmware a chance to be called, such as ACPI _PRx, _PSx
* Firmware method after native method ?
*/
if (platform_pci_set_power_state)
platform_pci_set_power_state(dev, state);
dev->current_state = state;
/* According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT
* INTERFACE SPECIFICATION, REV. 1.2", a device transitioning
* from D3hot to D0 _may_ perform an internal reset, thereby
* going to "D0 Uninitialized" rather than "D0 Initialized".
* For example, at least some versions of the 3c905B and the
* 3c556B exhibit this behaviour.
*
* At least some laptop BIOSen (e.g. the Thinkpad T21) leave
* devices in a D3hot state at boot. Consequently, we need to
* restore at least the BARs so that the device will be
* accessible to its driver.
*/
if (need_restore)
pci_restore_bars(dev);
return 0;
}
int (*platform_pci_choose_state)(struct pci_dev *dev, pm_message_t state);
/**
* pci_choose_state - Choose the power state of a PCI device
* @dev: PCI device to be suspended
* @state: target sleep state for the whole system. This is the value
* that is passed to suspend() function.
*
* Returns PCI power state suitable for given device and given system
* message.
*/
pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
{
int ret;
if (!pci_find_capability(dev, PCI_CAP_ID_PM))
return PCI_D0;
if (platform_pci_choose_state) {
ret = platform_pci_choose_state(dev, state);
if (ret >= 0)
state.event = ret;
}
switch (state.event) {
case PM_EVENT_ON:
return PCI_D0;
case PM_EVENT_FREEZE:
case PM_EVENT_PRETHAW:
/* REVISIT both freeze and pre-thaw "should" use D0 */
case PM_EVENT_SUSPEND:
return PCI_D3hot;
default:
printk("Unrecognized suspend event %d\n", state.event);
BUG();
}
return PCI_D0;
}
EXPORT_SYMBOL(pci_choose_state);
static int pci_save_pcie_state(struct pci_dev *dev)
{
int pos, i = 0;
struct pci_cap_saved_state *save_state;
u16 *cap;
pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
if (pos <= 0)
return 0;
save_state = kzalloc(sizeof(*save_state) + sizeof(u16) * 4, GFP_KERNEL);
if (!save_state) {
dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
return -ENOMEM;
}
cap = (u16 *)&save_state->data[0];
pci_read_config_word(dev, pos + PCI_EXP_DEVCTL, &cap[i++]);
pci_read_config_word(dev, pos + PCI_EXP_LNKCTL, &cap[i++]);
pci_read_config_word(dev, pos + PCI_EXP_SLTCTL, &cap[i++]);
pci_read_config_word(dev, pos + PCI_EXP_RTCTL, &cap[i++]);
pci_add_saved_cap(dev, save_state);
return 0;
}
static void pci_restore_pcie_state(struct pci_dev *dev)
{
int i = 0, pos;
struct pci_cap_saved_state *save_state;
u16 *cap;
save_state = pci_find_saved_cap(dev, PCI_CAP_ID_EXP);
pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
if (!save_state || pos <= 0)
return;
cap = (u16 *)&save_state->data[0];
pci_write_config_word(dev, pos + PCI_EXP_DEVCTL, cap[i++]);
pci_write_config_word(dev, pos + PCI_EXP_LNKCTL, cap[i++]);
pci_write_config_word(dev, pos + PCI_EXP_SLTCTL, cap[i++]);
pci_write_config_word(dev, pos + PCI_EXP_RTCTL, cap[i++]);
pci_remove_saved_cap(save_state);
kfree(save_state);
}
static int pci_save_pcix_state(struct pci_dev *dev)
{
int pos, i = 0;
struct pci_cap_saved_state *save_state;
u16 *cap;
pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
if (pos <= 0)
return 0;
save_state = kzalloc(sizeof(*save_state) + sizeof(u16), GFP_KERNEL);
if (!save_state) {
dev_err(&dev->dev, "Out of memory in pci_save_pcie_state\n");
return -ENOMEM;
}
cap = (u16 *)&save_state->data[0];
pci_read_config_word(dev, pos + PCI_X_CMD, &cap[i++]);
pci_add_saved_cap(dev, save_state);
return 0;
}
static void pci_restore_pcix_state(struct pci_dev *dev)
{
int i = 0, pos;
struct pci_cap_saved_state *save_state;
u16 *cap;
save_state = pci_find_saved_cap(dev, PCI_CAP_ID_PCIX);
pos = pci_find_capability(dev, PCI_CAP_ID_PCIX);
if (!save_state || pos <= 0)
return;
cap = (u16 *)&save_state->data[0];
pci_write_config_word(dev, pos + PCI_X_CMD, cap[i++]);
pci_remove_saved_cap(save_state);
kfree(save_state);
}
/**
* pci_save_state - save the PCI configuration space of a device before suspending
* @dev: - PCI device that we're dealing with
*/
int
pci_save_state(struct pci_dev *dev)
{
int i;
/* XXX: 100% dword access ok here? */
for (i = 0; i < 16; i++)
pci_read_config_dword(dev, i * 4,&dev->saved_config_space[i]);
if ((i = pci_save_pcie_state(dev)) != 0)
return i;
if ((i = pci_save_pcix_state(dev)) != 0)
return i;
return 0;
}
/**
* pci_restore_state - Restore the saved state of a PCI device
* @dev: - PCI device that we're dealing with
*/
int
pci_restore_state(struct pci_dev *dev)
{
int i;
int val;
/* PCI Express register must be restored first */
pci_restore_pcie_state(dev);
/*
* The Base Address register should be programmed before the command
* register(s)
*/
for (i = 15; i >= 0; i--) {
pci_read_config_dword(dev, i * 4, &val);
if (val != dev->saved_config_space[i]) {
printk(KERN_DEBUG "PM: Writing back config space on "
"device %s at offset %x (was %x, writing %x)\n",
pci_name(dev), i,
val, (int)dev->saved_config_space[i]);
pci_write_config_dword(dev,i * 4,
dev->saved_config_space[i]);
}
}
pci_restore_pcix_state(dev);
pci_restore_msi_state(dev);
return 0;
}
static int do_pci_enable_device(struct pci_dev *dev, int bars)
{
int err;
err = pci_set_power_state(dev, PCI_D0);
if (err < 0 && err != -EIO)
return err;
err = pcibios_enable_device(dev, bars);
if (err < 0)
return err;
pci_fixup_device(pci_fixup_enable, dev);
return 0;
}
/**
* __pci_reenable_device - Resume abandoned device
* @dev: PCI device to be resumed
*
* Note this function is a backend of pci_default_resume and is not supposed
* to be called by normal code, write proper resume handler and use it instead.
*/
int
__pci_reenable_device(struct pci_dev *dev)
{
if (atomic_read(&dev->enable_cnt))
return do_pci_enable_device(dev, (1 << PCI_NUM_RESOURCES) - 1);
return 0;
}
/**
* pci_enable_device_bars - Initialize some of a device for use
* @dev: PCI device to be initialized
* @bars: bitmask of BAR's that must be configured
*
* Initialize device before it's used by a driver. Ask low-level code
* to enable selected I/O and memory resources. Wake up the device if it
* was suspended. Beware, this function can fail.
*/
int
pci_enable_device_bars(struct pci_dev *dev, int bars)
{
int err;
if (atomic_add_return(1, &dev->enable_cnt) > 1)
return 0; /* already enabled */
err = do_pci_enable_device(dev, bars);
if (err < 0)
atomic_dec(&dev->enable_cnt);
return err;
}
/**
* pci_enable_device - Initialize device before it's used by a driver.
* @dev: PCI device to be initialized
*
* Initialize device before it's used by a driver. Ask low-level code
* to enable I/O and memory. Wake up the device if it was suspended.
* Beware, this function can fail.
*
* Note we don't actually enable the device many times if we call
* this function repeatedly (we just increment the count).
*/
int pci_enable_device(struct pci_dev *dev)
{
return pci_enable_device_bars(dev, (1 << PCI_NUM_RESOURCES) - 1);
}
/*
* Managed PCI resources. This manages device on/off, intx/msi/msix
* on/off and BAR regions. pci_dev itself records msi/msix status, so
* there's no need to track it separately. pci_devres is initialized
* when a device is enabled using managed PCI device enable interface.
*/
struct pci_devres {
unsigned int enabled:1;
unsigned int pinned:1;
unsigned int orig_intx:1;
unsigned int restore_intx:1;
u32 region_mask;
};
static void pcim_release(struct device *gendev, void *res)
{
struct pci_dev *dev = container_of(gendev, struct pci_dev, dev);
struct pci_devres *this = res;
int i;
if (dev->msi_enabled)
pci_disable_msi(dev);
if (dev->msix_enabled)
pci_disable_msix(dev);
for (i = 0; i < DEVICE_COUNT_RESOURCE; i++)
if (this->region_mask & (1 << i))
pci_release_region(dev, i);
if (this->restore_intx)
pci_intx(dev, this->orig_intx);
if (this->enabled && !this->pinned)
pci_disable_device(dev);
}
static struct pci_devres * get_pci_dr(struct pci_dev *pdev)
{
struct pci_devres *dr, *new_dr;
dr = devres_find(&pdev->dev, pcim_release, NULL, NULL);
if (dr)
return dr;
new_dr = devres_alloc(pcim_release, sizeof(*new_dr), GFP_KERNEL);
if (!new_dr)
return NULL;
return devres_get(&pdev->dev, new_dr, NULL, NULL);
}
static struct pci_devres * find_pci_dr(struct pci_dev *pdev)
{
if (pci_is_managed(pdev))
return devres_find(&pdev->dev, pcim_release, NULL, NULL);
return NULL;
}
/**
* pcim_enable_device - Managed pci_enable_device()
* @pdev: PCI device to be initialized
*
* Managed pci_enable_device().
*/
int pcim_enable_device(struct pci_dev *pdev)
{
struct pci_devres *dr;
int rc;
dr = get_pci_dr(pdev);
if (unlikely(!dr))
return -ENOMEM;
WARN_ON(!!dr->enabled);
rc = pci_enable_device(pdev);
if (!rc) {
pdev->is_managed = 1;
dr->enabled = 1;
}
return rc;
}
/**
* pcim_pin_device - Pin managed PCI device
* @pdev: PCI device to pin
*
* Pin managed PCI device @pdev. Pinned device won't be disabled on
* driver detach. @pdev must have been enabled with
* pcim_enable_device().
*/
void pcim_pin_device(struct pci_dev *pdev)
{
struct pci_devres *dr;
dr = find_pci_dr(pdev);
WARN_ON(!dr || !dr->enabled);
if (dr)
dr->pinned = 1;
}
/**
* pcibios_disable_device - disable arch specific PCI resources for device dev
* @dev: the PCI device to disable
*
* Disables architecture specific PCI resources for the device. This
* is the default implementation. Architecture implementations can
* override this.
*/
void __attribute__ ((weak)) pcibios_disable_device (struct pci_dev *dev) {}
/**
* pci_disable_device - Disable PCI device after use
* @dev: PCI device to be disabled
*
* Signal to the system that the PCI device is not in use by the system
* anymore. This only involves disabling PCI bus-mastering, if active.
*
* Note we don't actually disable the device until all callers of
* pci_device_enable() have called pci_device_disable().
*/
void
pci_disable_device(struct pci_dev *dev)
{
struct pci_devres *dr;
u16 pci_command;
dr = find_pci_dr(dev);
if (dr)
dr->enabled = 0;
if (atomic_sub_return(1, &dev->enable_cnt) != 0)
return;
pci_read_config_word(dev, PCI_COMMAND, &pci_command);
if (pci_command & PCI_COMMAND_MASTER) {
pci_command &= ~PCI_COMMAND_MASTER;
pci_write_config_word(dev, PCI_COMMAND, pci_command);
}
dev->is_busmaster = 0;
pcibios_disable_device(dev);
}
/**
* pci_enable_wake - enable device to generate PME# when suspended
* @dev: - PCI device to operate on
* @state: - Current state of device.
* @enable: - Flag to enable or disable generation
*
* Set the bits in the device's PM Capabilities to generate PME# when
* the system is suspended.
*
* -EIO is returned if device doesn't have PM Capabilities.
* -EINVAL is returned if device supports it, but can't generate wake events.
* 0 if operation is successful.
*
*/
int pci_enable_wake(struct pci_dev *dev, pci_power_t state, int enable)
{
int pm;
u16 value;
/* find PCI PM capability in list */
pm = pci_find_capability(dev, PCI_CAP_ID_PM);
/* If device doesn't support PM Capabilities, but request is to disable
* wake events, it's a nop; otherwise fail */
if (!pm)
return enable ? -EIO : 0;
/* Check device's ability to generate PME# */
pci_read_config_word(dev,pm+PCI_PM_PMC,&value);
value &= PCI_PM_CAP_PME_MASK;
value >>= ffs(PCI_PM_CAP_PME_MASK) - 1; /* First bit of mask */
/* Check if it can generate PME# from requested state. */
if (!value || !(value & (1 << state)))
return enable ? -EINVAL : 0;
pci_read_config_word(dev, pm + PCI_PM_CTRL, &value);
/* Clear PME_Status by writing 1 to it and enable PME# */
value |= PCI_PM_CTRL_PME_STATUS | PCI_PM_CTRL_PME_ENABLE;
if (!enable)
value &= ~PCI_PM_CTRL_PME_ENABLE;
pci_write_config_word(dev, pm + PCI_PM_CTRL, value);
return 0;
}
int
pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
{
u8 pin;
pin = dev->pin;
if (!pin)
return -1;
pin--;
while (dev->bus->self) {
pin = (pin + PCI_SLOT(dev->devfn)) % 4;
dev = dev->bus->self;
}
*bridge = dev;
return pin;
}
/**
* pci_release_region - Release a PCI bar
* @pdev: PCI device whose resources were previously reserved by pci_request_region
* @bar: BAR to release
*
* Releases the PCI I/O and memory resources previously reserved by a
* successful call to pci_request_region. Call this function only
* after all use of the PCI regions has ceased.
*/
void pci_release_region(struct pci_dev *pdev, int bar)
{
struct pci_devres *dr;
if (pci_resource_len(pdev, bar) == 0)
return;
if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
release_region(pci_resource_start(pdev, bar),
pci_resource_len(pdev, bar));
else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
release_mem_region(pci_resource_start(pdev, bar),
pci_resource_len(pdev, bar));
dr = find_pci_dr(pdev);
if (dr)
dr->region_mask &= ~(1 << bar);
}
/**
* pci_request_region - Reserved PCI I/O and memory resource
* @pdev: PCI device whose resources are to be reserved
* @bar: BAR to be reserved
* @res_name: Name to be associated with resource.
*
* Mark the PCI region associated with PCI device @pdev BR @bar as
* being reserved by owner @res_name. Do not access any
* address inside the PCI regions unless this call returns
* successfully.
*
* Returns 0 on success, or %EBUSY on error. A warning
* message is also printed on failure.
*/
int pci_request_region(struct pci_dev *pdev, int bar, const char *res_name)
{
struct pci_devres *dr;
if (pci_resource_len(pdev, bar) == 0)
return 0;
if (pci_resource_flags(pdev, bar) & IORESOURCE_IO) {
if (!request_region(pci_resource_start(pdev, bar),
pci_resource_len(pdev, bar), res_name))
goto err_out;
}
else if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM) {
if (!request_mem_region(pci_resource_start(pdev, bar),
pci_resource_len(pdev, bar), res_name))
goto err_out;
}
dr = find_pci_dr(pdev);
if (dr)
dr->region_mask |= 1 << bar;
return 0;
err_out:
printk (KERN_WARNING "PCI: Unable to reserve %s region #%d:%llx@%llx "
"for device %s\n",
pci_resource_flags(pdev, bar) & IORESOURCE_IO ? "I/O" : "mem",
bar + 1, /* PCI BAR # */
(unsigned long long)pci_resource_len(pdev, bar),
(unsigned long long)pci_resource_start(pdev, bar),
pci_name(pdev));
return -EBUSY;
}
/**
* pci_release_selected_regions - Release selected PCI I/O and memory resources
* @pdev: PCI device whose resources were previously reserved
* @bars: Bitmask of BARs to be released
*
* Release selected PCI I/O and memory resources previously reserved.
* Call this function only after all use of the PCI regions has ceased.
*/
void pci_release_selected_regions(struct pci_dev *pdev, int bars)
{
int i;
for (i = 0; i < 6; i++)
if (bars & (1 << i))
pci_release_region(pdev, i);
}
/**
* pci_request_selected_regions - Reserve selected PCI I/O and memory resources
* @pdev: PCI device whose resources are to be reserved
* @bars: Bitmask of BARs to be requested
* @res_name: Name to be associated with resource
*/
int pci_request_selected_regions(struct pci_dev *pdev, int bars,
const char *res_name)
{
int i;
for (i = 0; i < 6; i++)
if (bars & (1 << i))
if(pci_request_region(pdev, i, res_name))
goto err_out;
return 0;
err_out:
while(--i >= 0)
if (bars & (1 << i))
pci_release_region(pdev, i);
return -EBUSY;
}
/**
* pci_release_regions - Release reserved PCI I/O and memory resources
* @pdev: PCI device whose resources were previously reserved by pci_request_regions
*
* Releases all PCI I/O and memory resources previously reserved by a
* successful call to pci_request_regions. Call this function only
* after all use of the PCI regions has ceased.
*/
void pci_release_regions(struct pci_dev *pdev)
{
pci_release_selected_regions(pdev, (1 << 6) - 1);
}
/**
* pci_request_regions - Reserved PCI I/O and memory resources
* @pdev: PCI device whose resources are to be reserved
* @res_name: Name to be associated with resource.
*
* Mark all PCI regions associated with PCI device @pdev as
* being reserved by owner @res_name. Do not access any
* address inside the PCI regions unless this call returns
* successfully.
*
* Returns 0 on success, or %EBUSY on error. A warning
* message is also printed on failure.
*/
int pci_request_regions(struct pci_dev *pdev, const char *res_name)
{
return pci_request_selected_regions(pdev, ((1 << 6) - 1), res_name);
}
/**
* pci_set_master - enables bus-mastering for device dev
* @dev: the PCI device to enable
*
* Enables bus-mastering on the device and calls pcibios_set_master()
* to do the needed arch specific settings.
*/
void
pci_set_master(struct pci_dev *dev)
{
u16 cmd;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
if (! (cmd & PCI_COMMAND_MASTER)) {
pr_debug("PCI: Enabling bus mastering for device %s\n", pci_name(dev));
cmd |= PCI_COMMAND_MASTER;
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
dev->is_busmaster = 1;
pcibios_set_master(dev);
}
#ifdef PCI_DISABLE_MWI
int pci_set_mwi(struct pci_dev *dev)
{
return 0;
}
void pci_clear_mwi(struct pci_dev *dev)
{
}
#else
#ifndef PCI_CACHE_LINE_BYTES
#define PCI_CACHE_LINE_BYTES L1_CACHE_BYTES
#endif
/* This can be overridden by arch code. */
/* Don't forget this is measured in 32-bit words, not bytes */
u8 pci_cache_line_size = PCI_CACHE_LINE_BYTES / 4;
/**
* pci_set_cacheline_size - ensure the CACHE_LINE_SIZE register is programmed
* @dev: the PCI device for which MWI is to be enabled
*
* Helper function for pci_set_mwi.
* Originally copied from drivers/net/acenic.c.
* Copyright 1998-2001 by Jes Sorensen, <jes@trained-monkey.org>.
*
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
static int
pci_set_cacheline_size(struct pci_dev *dev)
{
u8 cacheline_size;
if (!pci_cache_line_size)
return -EINVAL; /* The system doesn't support MWI. */
/* Validate current setting: the PCI_CACHE_LINE_SIZE must be
equal to or multiple of the right value. */
pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
if (cacheline_size >= pci_cache_line_size &&
(cacheline_size % pci_cache_line_size) == 0)
return 0;
/* Write the correct value. */
pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, pci_cache_line_size);
/* Read it back. */
pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &cacheline_size);
if (cacheline_size == pci_cache_line_size)
return 0;
printk(KERN_DEBUG "PCI: cache line size of %d is not supported "
"by device %s\n", pci_cache_line_size << 2, pci_name(dev));
return -EINVAL;
}
/**
* pci_set_mwi - enables memory-write-invalidate PCI transaction
* @dev: the PCI device for which MWI is enabled
*
* Enables the Memory-Write-Invalidate transaction in %PCI_COMMAND,
* and then calls @pcibios_set_mwi to do the needed arch specific
* operations or a generic mwi-prep function.
*
* RETURNS: An appropriate -ERRNO error value on error, or zero for success.
*/
int
pci_set_mwi(struct pci_dev *dev)
{
int rc;
u16 cmd;
rc = pci_set_cacheline_size(dev);
if (rc)
return rc;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
if (! (cmd & PCI_COMMAND_INVALIDATE)) {
pr_debug("PCI: Enabling Mem-Wr-Inval for device %s\n", pci_name(dev));
cmd |= PCI_COMMAND_INVALIDATE;
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
return 0;
}
/**
* pci_clear_mwi - disables Memory-Write-Invalidate for device dev
* @dev: the PCI device to disable
*
* Disables PCI Memory-Write-Invalidate transaction on the device
*/
void
pci_clear_mwi(struct pci_dev *dev)
{
u16 cmd;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
if (cmd & PCI_COMMAND_INVALIDATE) {
cmd &= ~PCI_COMMAND_INVALIDATE;
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
}
#endif /* ! PCI_DISABLE_MWI */
/**
* pci_intx - enables/disables PCI INTx for device dev
* @pdev: the PCI device to operate on
* @enable: boolean: whether to enable or disable PCI INTx
*
* Enables/disables PCI INTx for device dev
*/
void
pci_intx(struct pci_dev *pdev, int enable)
{
u16 pci_command, new;
pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
if (enable) {
new = pci_command & ~PCI_COMMAND_INTX_DISABLE;
} else {
new = pci_command | PCI_COMMAND_INTX_DISABLE;
}
if (new != pci_command) {
struct pci_devres *dr;
pci_write_config_word(pdev, PCI_COMMAND, new);
dr = find_pci_dr(pdev);
if (dr && !dr->restore_intx) {
dr->restore_intx = 1;
dr->orig_intx = !enable;
}
}
}
/**
* pci_msi_off - disables any msi or msix capabilities
* @pdev: the PCI device to operate on
*
* If you want to use msi see pci_enable_msi and friends.
* This is a lower level primitive that allows us to disable
* msi operation at the device level.
*/
void pci_msi_off(struct pci_dev *dev)
{
int pos;
u16 control;
pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
if (pos) {
pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
control &= ~PCI_MSI_FLAGS_ENABLE;
pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
}
pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
if (pos) {
pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
control &= ~PCI_MSIX_FLAGS_ENABLE;
pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
}
}
#ifndef HAVE_ARCH_PCI_SET_DMA_MASK
/*
* These can be overridden by arch-specific implementations
*/
int
pci_set_dma_mask(struct pci_dev *dev, u64 mask)
{
if (!pci_dma_supported(dev, mask))
return -EIO;
dev->dma_mask = mask;
return 0;
}
int
pci_set_consistent_dma_mask(struct pci_dev *dev, u64 mask)
{
if (!pci_dma_supported(dev, mask))
return -EIO;
dev->dev.coherent_dma_mask = mask;
return 0;
}
#endif
/**
* pci_select_bars - Make BAR mask from the type of resource
* @dev: the PCI device for which BAR mask is made
* @flags: resource type mask to be selected
*
* This helper routine makes bar mask from the type of resource.
*/
int pci_select_bars(struct pci_dev *dev, unsigned long flags)
{
int i, bars = 0;
for (i = 0; i < PCI_NUM_RESOURCES; i++)
if (pci_resource_flags(dev, i) & flags)
bars |= (1 << i);
return bars;
}
static int __devinit pci_init(void)
{
struct pci_dev *dev = NULL;
while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
pci_fixup_device(pci_fixup_final, dev);
}
return 0;
}
static int __devinit pci_setup(char *str)
{
while (str) {
char *k = strchr(str, ',');
if (k)
*k++ = 0;
if (*str && (str = pcibios_setup(str)) && *str) {
if (!strcmp(str, "nomsi")) {
pci_no_msi();
} else if (!strncmp(str, "cbiosize=", 9)) {
pci_cardbus_io_size = memparse(str + 9, &str);
} else if (!strncmp(str, "cbmemsize=", 10)) {
pci_cardbus_mem_size = memparse(str + 10, &str);
} else {
printk(KERN_ERR "PCI: Unknown option `%s'\n",
str);
}
}
str = k;
}
return 0;
}
early_param("pci", pci_setup);
device_initcall(pci_init);
EXPORT_SYMBOL_GPL(pci_restore_bars);
EXPORT_SYMBOL(pci_enable_device_bars);
EXPORT_SYMBOL(pci_enable_device);
EXPORT_SYMBOL(pcim_enable_device);
EXPORT_SYMBOL(pcim_pin_device);
EXPORT_SYMBOL(pci_disable_device);
EXPORT_SYMBOL(pci_find_capability);
EXPORT_SYMBOL(pci_bus_find_capability);
EXPORT_SYMBOL(pci_release_regions);
EXPORT_SYMBOL(pci_request_regions);
EXPORT_SYMBOL(pci_release_region);
EXPORT_SYMBOL(pci_request_region);
EXPORT_SYMBOL(pci_release_selected_regions);
EXPORT_SYMBOL(pci_request_selected_regions);
EXPORT_SYMBOL(pci_set_master);
EXPORT_SYMBOL(pci_set_mwi);
EXPORT_SYMBOL(pci_clear_mwi);
EXPORT_SYMBOL_GPL(pci_intx);
EXPORT_SYMBOL(pci_set_dma_mask);
EXPORT_SYMBOL(pci_set_consistent_dma_mask);
EXPORT_SYMBOL(pci_assign_resource);
EXPORT_SYMBOL(pci_find_parent_resource);
EXPORT_SYMBOL(pci_select_bars);
EXPORT_SYMBOL(pci_set_power_state);
EXPORT_SYMBOL(pci_save_state);
EXPORT_SYMBOL(pci_restore_state);
EXPORT_SYMBOL(pci_enable_wake);