/*
* File: msi.c
* Purpose: PCI Message Signaled Interrupt (MSI)
*
* Copyright (C) 2003-2004 Intel
* Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
*/
#include <linux/mm.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/config.h>
#include <linux/ioport.h>
#include <linux/smp_lock.h>
#include <linux/pci.h>
#include <linux/proc_fs.h>
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/smp.h>
#include "pci.h"
#include "msi.h"
static DEFINE_SPINLOCK(msi_lock);
static struct msi_desc* msi_desc[NR_IRQS] = { [0 ... NR_IRQS-1] = NULL };
static kmem_cache_t* msi_cachep;
static int pci_msi_enable = 1;
static int last_alloc_vector = 0;
static int nr_released_vectors = 0;
static int nr_reserved_vectors = NR_HP_RESERVED_VECTORS;
static int nr_msix_devices = 0;
#ifndef CONFIG_X86_IO_APIC
int vector_irq[NR_VECTORS] = { [0 ... NR_VECTORS - 1] = -1};
u8 irq_vector[NR_IRQ_VECTORS] = { FIRST_DEVICE_VECTOR , 0 };
#endif
static void msi_cache_ctor(void *p, kmem_cache_t *cache, unsigned long flags)
{
memset(p, 0, NR_IRQS * sizeof(struct msi_desc));
}
static int msi_cache_init(void)
{
msi_cachep = kmem_cache_create("msi_cache",
NR_IRQS * sizeof(struct msi_desc),
0, SLAB_HWCACHE_ALIGN, msi_cache_ctor, NULL);
if (!msi_cachep)
return -ENOMEM;
return 0;
}
static void msi_set_mask_bit(unsigned int vector, int flag)
{
struct msi_desc *entry;
entry = (struct msi_desc *)msi_desc[vector];
if (!entry || !entry->dev || !entry->mask_base)
return;
switch (entry->msi_attrib.type) {
case PCI_CAP_ID_MSI:
{
int pos;
u32 mask_bits;
pos = (long)entry->mask_base;
pci_read_config_dword(entry->dev, pos, &mask_bits);
mask_bits &= ~(1);
mask_bits |= flag;
pci_write_config_dword(entry->dev, pos, mask_bits);
break;
}
case PCI_CAP_ID_MSIX:
{
int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
writel(flag, entry->mask_base + offset);
break;
}
default:
break;
}
}
#ifdef CONFIG_SMP
static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask)
{
struct msi_desc *entry;
struct msg_address address;
entry = (struct msi_desc *)msi_desc[vector];
if (!entry || !entry->dev)
return;
switch (entry->msi_attrib.type) {
case PCI_CAP_ID_MSI:
{
int pos;
if (!(pos = pci_find_capability(entry->dev, PCI_CAP_ID_MSI)))
return;
pci_read_config_dword(entry->dev, msi_lower_address_reg(pos),
&address.lo_address.value);
address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
address.lo_address.value |= (cpu_mask_to_apicid(cpu_mask) <<
MSI_TARGET_CPU_SHIFT);
entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask);
pci_write_config_dword(entry->dev, msi_lower_address_reg(pos),
address.lo_address.value);
break;
}
case PCI_CAP_ID_MSIX:
{
int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET;
address.lo_address.value = readl(entry->mask_base + offset);
address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
address.lo_address.value |= (cpu_mask_to_apicid(cpu_mask) <<
MSI_TARGET_CPU_SHIFT);
entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask);
writel(address.lo_address.value, entry->mask_base + offset);
break;
}
default:
break;
}
}
#ifdef CONFIG_IRQBALANCE
static inline void move_msi(int vector)
{
if (!cpus_empty(pending_irq_balance_cpumask[vector])) {
set_msi_affinity(vector, pending_irq_balance_cpumask[vector]);
cpus_clear(pending_irq_balance_cpumask[vector]);
}
}
#endif /* CONFIG_IRQBALANCE */
#endif /* CONFIG_SMP */
static void mask_MSI_irq(unsigned int vector)
{
msi_set_mask_bit(vector, 1);
}
static void unmask_MSI_irq(unsigned int vector)
{
msi_set_mask_bit(vector, 0);
}
static unsigned int startup_msi_irq_wo_maskbit(unsigned int vector)
{
struct msi_desc *entry;
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
entry = msi_desc[vector];
if (!entry || !entry->dev) {
spin_unlock_irqrestore(&msi_lock, flags);
return 0;
}
entry->msi_attrib.state = 1; /* Mark it active */
spin_unlock_irqrestore(&msi_lock, flags);
return 0; /* never anything pending */
}
static void release_msi(unsigned int vector);
static void shutdown_msi_irq(unsigned int vector)
{
release_msi(vector);
}
#define shutdown_msi_irq_wo_maskbit shutdown_msi_irq
static void enable_msi_irq_wo_maskbit(unsigned int vector) {}
static void disable_msi_irq_wo_maskbit(unsigned int vector) {}
static void ack_msi_irq_wo_maskbit(unsigned int vector) {}
static void end_msi_irq_wo_maskbit(unsigned int vector)
{
move_msi(vector);
ack_APIC_irq();
}
static unsigned int startup_msi_irq_w_maskbit(unsigned int vector)
{
struct msi_desc *entry;
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
entry = msi_desc[vector];
if (!entry || !entry->dev) {
spin_unlock_irqrestore(&msi_lock, flags);
return 0;
}
entry->msi_attrib.state = 1; /* Mark it active */
spin_unlock_irqrestore(&msi_lock, flags);
unmask_MSI_irq(vector);
return 0; /* never anything pending */
}
#define shutdown_msi_irq_w_maskbit shutdown_msi_irq
#define enable_msi_irq_w_maskbit unmask_MSI_irq
#define disable_msi_irq_w_maskbit mask_MSI_irq
#define ack_msi_irq_w_maskbit mask_MSI_irq
static void end_msi_irq_w_maskbit(unsigned int vector)
{
move_msi(vector);
unmask_MSI_irq(vector);
ack_APIC_irq();
}
/*
* Interrupt Type for MSI-X PCI/PCI-X/PCI-Express Devices,
* which implement the MSI-X Capability Structure.
*/
static struct hw_interrupt_type msix_irq_type = {
.typename = "PCI-MSI-X",
.startup = startup_msi_irq_w_maskbit,
.shutdown = shutdown_msi_irq_w_maskbit,
.enable = enable_msi_irq_w_maskbit,
.disable = disable_msi_irq_w_maskbit,
.ack = ack_msi_irq_w_maskbit,
.end = end_msi_irq_w_maskbit,
.set_affinity = set_msi_irq_affinity
};
/*
* Interrupt Type for MSI PCI/PCI-X/PCI-Express Devices,
* which implement the MSI Capability Structure with
* Mask-and-Pending Bits.
*/
static struct hw_interrupt_type msi_irq_w_maskbit_type = {
.typename = "PCI-MSI",
.startup = startup_msi_irq_w_maskbit,
.shutdown = shutdown_msi_irq_w_maskbit,
.enable = enable_msi_irq_w_maskbit,
.disable = disable_msi_irq_w_maskbit,
.ack = ack_msi_irq_w_maskbit,
.end = end_msi_irq_w_maskbit,
.set_affinity = set_msi_irq_affinity
};
/*
* Interrupt Type for MSI PCI/PCI-X/PCI-Express Devices,
* which implement the MSI Capability Structure without
* Mask-and-Pending Bits.
*/
static struct hw_interrupt_type msi_irq_wo_maskbit_type = {
.typename = "PCI-MSI",
.startup = startup_msi_irq_wo_maskbit,
.shutdown = shutdown_msi_irq_wo_maskbit,
.enable = enable_msi_irq_wo_maskbit,
.disable = disable_msi_irq_wo_maskbit,
.ack = ack_msi_irq_wo_maskbit,
.end = end_msi_irq_wo_maskbit,
.set_affinity = set_msi_irq_affinity
};
static void msi_data_init(struct msg_data *msi_data,
unsigned int vector)
{
memset(msi_data, 0, sizeof(struct msg_data));
msi_data->vector = (u8)vector;
msi_data->delivery_mode = MSI_DELIVERY_MODE;
msi_data->level = MSI_LEVEL_MODE;
msi_data->trigger = MSI_TRIGGER_MODE;
}
static void msi_address_init(struct msg_address *msi_address)
{
unsigned int dest_id;
memset(msi_address, 0, sizeof(struct msg_address));
msi_address->hi_address = (u32)0;
dest_id = (MSI_ADDRESS_HEADER << MSI_ADDRESS_HEADER_SHIFT);
msi_address->lo_address.u.dest_mode = MSI_DEST_MODE;
msi_address->lo_address.u.redirection_hint = MSI_REDIRECTION_HINT_MODE;
msi_address->lo_address.u.dest_id = dest_id;
msi_address->lo_address.value |= (MSI_TARGET_CPU << MSI_TARGET_CPU_SHIFT);
}
static int msi_free_vector(struct pci_dev* dev, int vector, int reassign);
static int assign_msi_vector(void)
{
static int new_vector_avail = 1;
int vector;
unsigned long flags;
/*
* msi_lock is provided to ensure that successful allocation of MSI
* vector is assigned unique among drivers.
*/
spin_lock_irqsave(&msi_lock, flags);
if (!new_vector_avail) {
int free_vector = 0;
/*
* vector_irq[] = -1 indicates that this specific vector is:
* - assigned for MSI (since MSI have no associated IRQ) or
* - assigned for legacy if less than 16, or
* - having no corresponding 1:1 vector-to-IOxAPIC IRQ mapping
* vector_irq[] = 0 indicates that this vector, previously
* assigned for MSI, is freed by hotplug removed operations.
* This vector will be reused for any subsequent hotplug added
* operations.
* vector_irq[] > 0 indicates that this vector is assigned for
* IOxAPIC IRQs. This vector and its value provides a 1-to-1
* vector-to-IOxAPIC IRQ mapping.
*/
for (vector = FIRST_DEVICE_VECTOR; vector < NR_IRQS; vector++) {
if (vector_irq[vector] != 0)
continue;
free_vector = vector;
if (!msi_desc[vector])
break;
else
continue;
}
if (!free_vector) {
spin_unlock_irqrestore(&msi_lock, flags);
return -EBUSY;
}
vector_irq[free_vector] = -1;
nr_released_vectors--;
spin_unlock_irqrestore(&msi_lock, flags);
if (msi_desc[free_vector] != NULL) {
struct pci_dev *dev;
int tail;
/* free all linked vectors before re-assign */
do {
spin_lock_irqsave(&msi_lock, flags);
dev = msi_desc[free_vector]->dev;
tail = msi_desc[free_vector]->link.tail;
spin_unlock_irqrestore(&msi_lock, flags);
msi_free_vector(dev, tail, 1);
} while (free_vector != tail);
}
return free_vector;
}
vector = assign_irq_vector(AUTO_ASSIGN);
last_alloc_vector = vector;
if (vector == LAST_DEVICE_VECTOR)
new_vector_avail = 0;
spin_unlock_irqrestore(&msi_lock, flags);
return vector;
}
static int get_new_vector(void)
{
int vector;
if ((vector = assign_msi_vector()) > 0)
set_intr_gate(vector, interrupt[vector]);
return vector;
}
static int msi_init(void)
{
static int status = -ENOMEM;
if (!status)
return status;
if (pci_msi_quirk) {
pci_msi_enable = 0;
printk(KERN_WARNING "PCI: MSI quirk detected. MSI disabled.\n");
status = -EINVAL;
return status;
}
if ((status = msi_cache_init()) < 0) {
pci_msi_enable = 0;
printk(KERN_WARNING "PCI: MSI cache init failed\n");
return status;
}
last_alloc_vector = assign_irq_vector(AUTO_ASSIGN);
if (last_alloc_vector < 0) {
pci_msi_enable = 0;
printk(KERN_WARNING "PCI: No interrupt vectors available for MSI\n");
status = -EBUSY;
return status;
}
vector_irq[last_alloc_vector] = 0;
nr_released_vectors++;
return status;
}
static int get_msi_vector(struct pci_dev *dev)
{
return get_new_vector();
}
static struct msi_desc* alloc_msi_entry(void)
{
struct msi_desc *entry;
entry = (struct msi_desc*) kmem_cache_alloc(msi_cachep, SLAB_KERNEL);
if (!entry)
return NULL;
memset(entry, 0, sizeof(struct msi_desc));
entry->link.tail = entry->link.head = 0; /* single message */
entry->dev = NULL;
return entry;
}
static void attach_msi_entry(struct msi_desc *entry, int vector)
{
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
msi_desc[vector] = entry;
spin_unlock_irqrestore(&msi_lock, flags);
}
static void irq_handler_init(int cap_id, int pos, int mask)
{
spin_lock(&irq_desc[pos].lock);
if (cap_id == PCI_CAP_ID_MSIX)
irq_desc[pos].handler = &msix_irq_type;
else {
if (!mask)
irq_desc[pos].handler = &msi_irq_wo_maskbit_type;
else
irq_desc[pos].handler = &msi_irq_w_maskbit_type;
}
spin_unlock(&irq_desc[pos].lock);
}
static void enable_msi_mode(struct pci_dev *dev, int pos, int type)
{
u16 control;
pci_read_config_word(dev, msi_control_reg(pos), &control);
if (type == PCI_CAP_ID_MSI) {
/* Set enabled bits to single MSI & enable MSI_enable bit */
msi_enable(control, 1);
pci_write_config_word(dev, msi_control_reg(pos), control);
} else {
msix_enable(control);
pci_write_config_word(dev, msi_control_reg(pos), control);
}
if (pci_find_capability(dev, PCI_CAP_ID_EXP)) {
/* PCI Express Endpoint device detected */
u16 cmd;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
cmd |= PCI_COMMAND_INTX_DISABLE;
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
}
static void disable_msi_mode(struct pci_dev *dev, int pos, int type)
{
u16 control;
pci_read_config_word(dev, msi_control_reg(pos), &control);
if (type == PCI_CAP_ID_MSI) {
/* Set enabled bits to single MSI & enable MSI_enable bit */
msi_disable(control);
pci_write_config_word(dev, msi_control_reg(pos), control);
} else {
msix_disable(control);
pci_write_config_word(dev, msi_control_reg(pos), control);
}
if (pci_find_capability(dev, PCI_CAP_ID_EXP)) {
/* PCI Express Endpoint device detected */
u16 cmd;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
cmd &= ~PCI_COMMAND_INTX_DISABLE;
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
}
static int msi_lookup_vector(struct pci_dev *dev, int type)
{
int vector;
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
for (vector = FIRST_DEVICE_VECTOR; vector < NR_IRQS; vector++) {
if (!msi_desc[vector] || msi_desc[vector]->dev != dev ||
msi_desc[vector]->msi_attrib.type != type ||
msi_desc[vector]->msi_attrib.default_vector != dev->irq)
continue;
spin_unlock_irqrestore(&msi_lock, flags);
/* This pre-assigned MSI vector for this device
already exits. Override dev->irq with this vector */
dev->irq = vector;
return 0;
}
spin_unlock_irqrestore(&msi_lock, flags);
return -EACCES;
}
void pci_scan_msi_device(struct pci_dev *dev)
{
if (!dev)
return;
if (pci_find_capability(dev, PCI_CAP_ID_MSIX) > 0)
nr_msix_devices++;
else if (pci_find_capability(dev, PCI_CAP_ID_MSI) > 0)
nr_reserved_vectors++;
}
/**
* msi_capability_init - configure device's MSI capability structure
* @dev: pointer to the pci_dev data structure of MSI device function
*
* Setup the MSI capability structure of device funtion with a single
* MSI vector, regardless of device function is capable of handling
* multiple messages. A return of zero indicates the successful setup
* of an entry zero with the new MSI vector or non-zero for otherwise.
**/
static int msi_capability_init(struct pci_dev *dev)
{
struct msi_desc *entry;
struct msg_address address;
struct msg_data data;
int pos, vector;
u16 control;
pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
pci_read_config_word(dev, msi_control_reg(pos), &control);
/* MSI Entry Initialization */
if (!(entry = alloc_msi_entry()))
return -ENOMEM;
if ((vector = get_msi_vector(dev)) < 0) {
kmem_cache_free(msi_cachep, entry);
return -EBUSY;
}
entry->link.head = vector;
entry->link.tail = vector;
entry->msi_attrib.type = PCI_CAP_ID_MSI;
entry->msi_attrib.state = 0; /* Mark it not active */
entry->msi_attrib.entry_nr = 0;
entry->msi_attrib.maskbit = is_mask_bit_support(control);
entry->msi_attrib.default_vector = dev->irq; /* Save IOAPIC IRQ */
dev->irq = vector;
entry->dev = dev;
if (is_mask_bit_support(control)) {
entry->mask_base = (void __iomem *)(long)msi_mask_bits_reg(pos,
is_64bit_address(control));
}
/* Replace with MSI handler */
irq_handler_init(PCI_CAP_ID_MSI, vector, entry->msi_attrib.maskbit);
/* Configure MSI capability structure */
msi_address_init(&address);
msi_data_init(&data, vector);
entry->msi_attrib.current_cpu = ((address.lo_address.u.dest_id >>
MSI_TARGET_CPU_SHIFT) & MSI_TARGET_CPU_MASK);
pci_write_config_dword(dev, msi_lower_address_reg(pos),
address.lo_address.value);
if (is_64bit_address(control)) {
pci_write_config_dword(dev,
msi_upper_address_reg(pos), address.hi_address);
pci_write_config_word(dev,
msi_data_reg(pos, 1), *((u32*)&data));
} else
pci_write_config_word(dev,
msi_data_reg(pos, 0), *((u32*)&data));
if (entry->msi_attrib.maskbit) {
unsigned int maskbits, temp;
/* All MSIs are unmasked by default, Mask them all */
pci_read_config_dword(dev,
msi_mask_bits_reg(pos, is_64bit_address(control)),
&maskbits);
temp = (1 << multi_msi_capable(control));
temp = ((temp - 1) & ~temp);
maskbits |= temp;
pci_write_config_dword(dev,
msi_mask_bits_reg(pos, is_64bit_address(control)),
maskbits);
}
attach_msi_entry(entry, vector);
/* Set MSI enabled bits */
enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
return 0;
}
/**
* msix_capability_init - configure device's MSI-X capability
* @dev: pointer to the pci_dev data structure of MSI-X device function
*
* Setup the MSI-X capability structure of device funtion with a
* single MSI-X vector. A return of zero indicates the successful setup of
* requested MSI-X entries with allocated vectors or non-zero for otherwise.
**/
static int msix_capability_init(struct pci_dev *dev,
struct msix_entry *entries, int nvec)
{
struct msi_desc *head = NULL, *tail = NULL, *entry = NULL;
struct msg_address address;
struct msg_data data;
int vector, pos, i, j, nr_entries, temp = 0;
u32 phys_addr, table_offset;
u16 control;
u8 bir;
void __iomem *base;
pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
/* Request & Map MSI-X table region */
pci_read_config_word(dev, msi_control_reg(pos), &control);
nr_entries = multi_msix_capable(control);
pci_read_config_dword(dev, msix_table_offset_reg(pos),
&table_offset);
bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
phys_addr = pci_resource_start (dev, bir);
phys_addr += (u32)(table_offset & ~PCI_MSIX_FLAGS_BIRMASK);
base = ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
if (base == NULL)
return -ENOMEM;
/* MSI-X Table Initialization */
for (i = 0; i < nvec; i++) {
entry = alloc_msi_entry();
if (!entry)
break;
if ((vector = get_msi_vector(dev)) < 0)
break;
j = entries[i].entry;
entries[i].vector = vector;
entry->msi_attrib.type = PCI_CAP_ID_MSIX;
entry->msi_attrib.state = 0; /* Mark it not active */
entry->msi_attrib.entry_nr = j;
entry->msi_attrib.maskbit = 1;
entry->msi_attrib.default_vector = dev->irq;
entry->dev = dev;
entry->mask_base = base;
if (!head) {
entry->link.head = vector;
entry->link.tail = vector;
head = entry;
} else {
entry->link.head = temp;
entry->link.tail = tail->link.tail;
tail->link.tail = vector;
head->link.head = vector;
}
temp = vector;
tail = entry;
/* Replace with MSI-X handler */
irq_handler_init(PCI_CAP_ID_MSIX, vector, 1);
/* Configure MSI-X capability structure */
msi_address_init(&address);
msi_data_init(&data, vector);
entry->msi_attrib.current_cpu =
((address.lo_address.u.dest_id >>
MSI_TARGET_CPU_SHIFT) & MSI_TARGET_CPU_MASK);
writel(address.lo_address.value,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
writel(address.hi_address,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
writel(*(u32*)&data,
base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_DATA_OFFSET);
attach_msi_entry(entry, vector);
}
if (i != nvec) {
i--;
for (; i >= 0; i--) {
vector = (entries + i)->vector;
msi_free_vector(dev, vector, 0);
(entries + i)->vector = 0;
}
return -EBUSY;
}
/* Set MSI-X enabled bits */
enable_msi_mode(dev, pos, PCI_CAP_ID_MSIX);
return 0;
}
/**
* pci_enable_msi - configure device's MSI capability structure
* @dev: pointer to the pci_dev data structure of MSI device function
*
* Setup the MSI capability structure of device function with
* a single MSI vector upon its software driver call to request for
* MSI mode enabled on its hardware device function. A return of zero
* indicates the successful setup of an entry zero with the new MSI
* vector or non-zero for otherwise.
**/
int pci_enable_msi(struct pci_dev* dev)
{
int pos, temp, status = -EINVAL;
u16 control;
if (!pci_msi_enable || !dev)
return status;
temp = dev->irq;
if ((status = msi_init()) < 0)
return status;
if (!(pos = pci_find_capability(dev, PCI_CAP_ID_MSI)))
return -EINVAL;
pci_read_config_word(dev, msi_control_reg(pos), &control);
if (control & PCI_MSI_FLAGS_ENABLE)
return 0; /* Already in MSI mode */
if (!msi_lookup_vector(dev, PCI_CAP_ID_MSI)) {
/* Lookup Sucess */
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
if (!vector_irq[dev->irq]) {
msi_desc[dev->irq]->msi_attrib.state = 0;
vector_irq[dev->irq] = -1;
nr_released_vectors--;
spin_unlock_irqrestore(&msi_lock, flags);
enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
return 0;
}
spin_unlock_irqrestore(&msi_lock, flags);
dev->irq = temp;
}
/* Check whether driver already requested for MSI-X vectors */
if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)) > 0 &&
!msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
printk(KERN_INFO "PCI: %s: Can't enable MSI. "
"Device already has MSI-X vectors assigned\n",
pci_name(dev));
dev->irq = temp;
return -EINVAL;
}
status = msi_capability_init(dev);
if (!status) {
if (!pos)
nr_reserved_vectors--; /* Only MSI capable */
else if (nr_msix_devices > 0)
nr_msix_devices--; /* Both MSI and MSI-X capable,
but choose enabling MSI */
}
return status;
}
void pci_disable_msi(struct pci_dev* dev)
{
struct msi_desc *entry;
int pos, default_vector;
u16 control;
unsigned long flags;
if (!dev || !(pos = pci_find_capability(dev, PCI_CAP_ID_MSI)))
return;
pci_read_config_word(dev, msi_control_reg(pos), &control);
if (!(control & PCI_MSI_FLAGS_ENABLE))
return;
spin_lock_irqsave(&msi_lock, flags);
entry = msi_desc[dev->irq];
if (!entry || !entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
spin_unlock_irqrestore(&msi_lock, flags);
return;
}
if (entry->msi_attrib.state) {
spin_unlock_irqrestore(&msi_lock, flags);
printk(KERN_WARNING "PCI: %s: pci_disable_msi() called without "
"free_irq() on MSI vector %d\n",
pci_name(dev), dev->irq);
BUG_ON(entry->msi_attrib.state > 0);
} else {
vector_irq[dev->irq] = 0; /* free it */
nr_released_vectors++;
default_vector = entry->msi_attrib.default_vector;
spin_unlock_irqrestore(&msi_lock, flags);
/* Restore dev->irq to its default pin-assertion vector */
dev->irq = default_vector;
disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
PCI_CAP_ID_MSI);
}
}
static void release_msi(unsigned int vector)
{
struct msi_desc *entry;
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
entry = msi_desc[vector];
if (entry && entry->dev)
entry->msi_attrib.state = 0; /* Mark it not active */
spin_unlock_irqrestore(&msi_lock, flags);
}
static int msi_free_vector(struct pci_dev* dev, int vector, int reassign)
{
struct msi_desc *entry;
int head, entry_nr, type;
void __iomem *base;
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
entry = msi_desc[vector];
if (!entry || entry->dev != dev) {
spin_unlock_irqrestore(&msi_lock, flags);
return -EINVAL;
}
type = entry->msi_attrib.type;
entry_nr = entry->msi_attrib.entry_nr;
head = entry->link.head;
base = entry->mask_base;
msi_desc[entry->link.head]->link.tail = entry->link.tail;
msi_desc[entry->link.tail]->link.head = entry->link.head;
entry->dev = NULL;
if (!reassign) {
vector_irq[vector] = 0;
nr_released_vectors++;
}
msi_desc[vector] = NULL;
spin_unlock_irqrestore(&msi_lock, flags);
kmem_cache_free(msi_cachep, entry);
if (type == PCI_CAP_ID_MSIX) {
if (!reassign)
writel(1, base +
entry_nr * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
if (head == vector) {
/*
* Detect last MSI-X vector to be released.
* Release the MSI-X memory-mapped table.
*/
int pos, nr_entries;
u32 phys_addr, table_offset;
u16 control;
u8 bir;
pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
pci_read_config_word(dev, msi_control_reg(pos),
&control);
nr_entries = multi_msix_capable(control);
pci_read_config_dword(dev, msix_table_offset_reg(pos),
&table_offset);
bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
phys_addr = pci_resource_start (dev, bir);
phys_addr += (u32)(table_offset &
~PCI_MSIX_FLAGS_BIRMASK);
iounmap(base);
}
}
return 0;
}
static int reroute_msix_table(int head, struct msix_entry *entries, int *nvec)
{
int vector = head, tail = 0;
int i, j = 0, nr_entries = 0;
void __iomem *base;
unsigned long flags;
spin_lock_irqsave(&msi_lock, flags);
while (head != tail) {
nr_entries++;
tail = msi_desc[vector]->link.tail;
if (entries[0].entry == msi_desc[vector]->msi_attrib.entry_nr)
j = vector;
vector = tail;
}
if (*nvec > nr_entries) {
spin_unlock_irqrestore(&msi_lock, flags);
*nvec = nr_entries;
return -EINVAL;
}
vector = ((j > 0) ? j : head);
for (i = 0; i < *nvec; i++) {
j = msi_desc[vector]->msi_attrib.entry_nr;
msi_desc[vector]->msi_attrib.state = 0; /* Mark it not active */
vector_irq[vector] = -1; /* Mark it busy */
nr_released_vectors--;
entries[i].vector = vector;
if (j != (entries + i)->entry) {
base = msi_desc[vector]->mask_base;
msi_desc[vector]->msi_attrib.entry_nr =
(entries + i)->entry;
writel( readl(base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET), base +
(entries + i)->entry * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
writel( readl(base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET), base +
(entries + i)->entry * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
writel( (readl(base + j * PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_DATA_OFFSET) & 0xff00) | vector,
base + (entries+i)->entry*PCI_MSIX_ENTRY_SIZE +
PCI_MSIX_ENTRY_DATA_OFFSET);
}
vector = msi_desc[vector]->link.tail;
}
spin_unlock_irqrestore(&msi_lock, flags);
return 0;
}
/**
* pci_enable_msix - configure device's MSI-X capability structure
* @dev: pointer to the pci_dev data structure of MSI-X device function
* @data: pointer to an array of MSI-X entries
* @nvec: number of MSI-X vectors requested for allocation by device driver
*
* Setup the MSI-X capability structure of device function with the number
* of requested vectors upon its software driver call to request for
* MSI-X mode enabled on its hardware device function. A return of zero
* indicates the successful configuration of MSI-X capability structure
* with new allocated MSI-X vectors. A return of < 0 indicates a failure.
* Or a return of > 0 indicates that driver request is exceeding the number
* of vectors available. Driver should use the returned value to re-send
* its request.
**/
int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
{
int status, pos, nr_entries, free_vectors;
int i, j, temp;
u16 control;
unsigned long flags;
if (!pci_msi_enable || !dev || !entries)
return -EINVAL;
if ((status = msi_init()) < 0)
return status;
if (!(pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)))
return -EINVAL;
pci_read_config_word(dev, msi_control_reg(pos), &control);
if (control & PCI_MSIX_FLAGS_ENABLE)
return -EINVAL; /* Already in MSI-X mode */
nr_entries = multi_msix_capable(control);
if (nvec > nr_entries)
return -EINVAL;
/* Check for any invalid entries */
for (i = 0; i < nvec; i++) {
if (entries[i].entry >= nr_entries)
return -EINVAL; /* invalid entry */
for (j = i + 1; j < nvec; j++) {
if (entries[i].entry == entries[j].entry)
return -EINVAL; /* duplicate entry */
}
}
temp = dev->irq;
if (!msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
/* Lookup Sucess */
nr_entries = nvec;
/* Reroute MSI-X table */
if (reroute_msix_table(dev->irq, entries, &nr_entries)) {
/* #requested > #previous-assigned */
dev->irq = temp;
return nr_entries;
}
dev->irq = temp;
enable_msi_mode(dev, pos, PCI_CAP_ID_MSIX);
return 0;
}
/* Check whether driver already requested for MSI vector */
if (pci_find_capability(dev, PCI_CAP_ID_MSI) > 0 &&
!msi_lookup_vector(dev, PCI_CAP_ID_MSI)) {
printk(KERN_INFO "PCI: %s: Can't enable MSI-X. "
"Device already has an MSI vector assigned\n",
pci_name(dev));
dev->irq = temp;
return -EINVAL;
}
spin_lock_irqsave(&msi_lock, flags);
/*
* msi_lock is provided to ensure that enough vectors resources are
* available before granting.
*/
free_vectors = pci_vector_resources(last_alloc_vector,
nr_released_vectors);
/* Ensure that each MSI/MSI-X device has one vector reserved by
default to avoid any MSI-X driver to take all available
resources */
free_vectors -= nr_reserved_vectors;
/* Find the average of free vectors among MSI-X devices */
if (nr_msix_devices > 0)
free_vectors /= nr_msix_devices;
spin_unlock_irqrestore(&msi_lock, flags);
if (nvec > free_vectors) {
if (free_vectors > 0)
return free_vectors;
else
return -EBUSY;
}
status = msix_capability_init(dev, entries, nvec);
if (!status && nr_msix_devices > 0)
nr_msix_devices--;
return status;
}
void pci_disable_msix(struct pci_dev* dev)
{
int pos, temp;
u16 control;
if (!dev || !(pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)))
return;
pci_read_config_word(dev, msi_control_reg(pos), &control);
if (!(control & PCI_MSIX_FLAGS_ENABLE))
return;
temp = dev->irq;
if (!msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
int state, vector, head, tail = 0, warning = 0;
unsigned long flags;
vector = head = dev->irq;
spin_lock_irqsave(&msi_lock, flags);
while (head != tail) {
state = msi_desc[vector]->msi_attrib.state;
if (state)
warning = 1;
else {
vector_irq[vector] = 0; /* free it */
nr_released_vectors++;
}
tail = msi_desc[vector]->link.tail;
vector = tail;
}
spin_unlock_irqrestore(&msi_lock, flags);
if (warning) {
dev->irq = temp;
printk(KERN_WARNING "PCI: %s: pci_disable_msix() called without "
"free_irq() on all MSI-X vectors\n",
pci_name(dev));
BUG_ON(warning > 0);
} else {
dev->irq = temp;
disable_msi_mode(dev,
pci_find_capability(dev, PCI_CAP_ID_MSIX),
PCI_CAP_ID_MSIX);
}
}
}
/**
* msi_remove_pci_irq_vectors - reclaim MSI(X) vectors to unused state
* @dev: pointer to the pci_dev data structure of MSI(X) device function
*
* Being called during hotplug remove, from which the device funciton
* is hot-removed. All previous assigned MSI/MSI-X vectors, if
* allocated for this device function, are reclaimed to unused state,
* which may be used later on.
**/
void msi_remove_pci_irq_vectors(struct pci_dev* dev)
{
int state, pos, temp;
unsigned long flags;
if (!pci_msi_enable || !dev)
return;
temp = dev->irq; /* Save IOAPIC IRQ */
if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSI)) > 0 &&
!msi_lookup_vector(dev, PCI_CAP_ID_MSI)) {
spin_lock_irqsave(&msi_lock, flags);
state = msi_desc[dev->irq]->msi_attrib.state;
spin_unlock_irqrestore(&msi_lock, flags);
if (state) {
printk(KERN_WARNING "PCI: %s: msi_remove_pci_irq_vectors() "
"called without free_irq() on MSI vector %d\n",
pci_name(dev), dev->irq);
BUG_ON(state > 0);
} else /* Release MSI vector assigned to this device */
msi_free_vector(dev, dev->irq, 0);
dev->irq = temp; /* Restore IOAPIC IRQ */
}
if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)) > 0 &&
!msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
int vector, head, tail = 0, warning = 0;
void __iomem *base = NULL;
vector = head = dev->irq;
while (head != tail) {
spin_lock_irqsave(&msi_lock, flags);
state = msi_desc[vector]->msi_attrib.state;
tail = msi_desc[vector]->link.tail;
base = msi_desc[vector]->mask_base;
spin_unlock_irqrestore(&msi_lock, flags);
if (state)
warning = 1;
else if (vector != head) /* Release MSI-X vector */
msi_free_vector(dev, vector, 0);
vector = tail;
}
msi_free_vector(dev, vector, 0);
if (warning) {
/* Force to release the MSI-X memory-mapped table */
u32 phys_addr, table_offset;
u16 control;
u8 bir;
pci_read_config_word(dev, msi_control_reg(pos),
&control);
pci_read_config_dword(dev, msix_table_offset_reg(pos),
&table_offset);
bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
phys_addr = pci_resource_start (dev, bir);
phys_addr += (u32)(table_offset &
~PCI_MSIX_FLAGS_BIRMASK);
iounmap(base);
printk(KERN_WARNING "PCI: %s: msi_remove_pci_irq_vectors() "
"called without free_irq() on all MSI-X vectors\n",
pci_name(dev));
BUG_ON(warning > 0);
}
dev->irq = temp; /* Restore IOAPIC IRQ */
}
}
EXPORT_SYMBOL(pci_enable_msi);
EXPORT_SYMBOL(pci_disable_msi);
EXPORT_SYMBOL(pci_enable_msix);
EXPORT_SYMBOL(pci_disable_msix);
