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path: root/drivers/pci/msi.c
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-rw-r--r--drivers/pci/msi.c398
1 files changed, 188 insertions, 210 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 435c1958a7b7..9e1321d0d5e6 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -24,20 +24,8 @@
#include "pci.h"
#include "msi.h"
-static struct kmem_cache* msi_cachep;
-
static int pci_msi_enable = 1;
-static int msi_cache_init(void)
-{
- msi_cachep = kmem_cache_create("msi_cache", sizeof(struct msi_desc),
- 0, SLAB_HWCACHE_ALIGN, NULL, NULL);
- if (!msi_cachep)
- return -ENOMEM;
-
- return 0;
-}
-
static void msi_set_enable(struct pci_dev *dev, int enable)
{
int pos;
@@ -68,6 +56,29 @@ static void msix_set_enable(struct pci_dev *dev, int enable)
}
}
+static void msix_flush_writes(unsigned int irq)
+{
+ struct msi_desc *entry;
+
+ entry = get_irq_msi(irq);
+ BUG_ON(!entry || !entry->dev);
+ switch (entry->msi_attrib.type) {
+ case PCI_CAP_ID_MSI:
+ /* nothing to do */
+ break;
+ case PCI_CAP_ID_MSIX:
+ {
+ int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
+ PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
+ readl(entry->mask_base + offset);
+ break;
+ }
+ default:
+ BUG();
+ break;
+ }
+}
+
static void msi_set_mask_bit(unsigned int irq, int flag)
{
struct msi_desc *entry;
@@ -187,41 +198,28 @@ void write_msi_msg(unsigned int irq, struct msi_msg *msg)
void mask_msi_irq(unsigned int irq)
{
msi_set_mask_bit(irq, 1);
+ msix_flush_writes(irq);
}
void unmask_msi_irq(unsigned int irq)
{
msi_set_mask_bit(irq, 0);
+ msix_flush_writes(irq);
}
-static int msi_free_irq(struct pci_dev* dev, int irq);
-
-static int msi_init(void)
-{
- static int status = -ENOMEM;
-
- if (!status)
- return status;
+static int msi_free_irqs(struct pci_dev* dev);
- status = msi_cache_init();
- if (status < 0) {
- pci_msi_enable = 0;
- printk(KERN_WARNING "PCI: MSI cache init failed\n");
- return status;
- }
-
- return status;
-}
static struct msi_desc* alloc_msi_entry(void)
{
struct msi_desc *entry;
- entry = kmem_cache_zalloc(msi_cachep, GFP_KERNEL);
+ entry = kzalloc(sizeof(struct msi_desc), GFP_KERNEL);
if (!entry)
return NULL;
- entry->link.tail = entry->link.head = 0; /* single message */
+ INIT_LIST_HEAD(&entry->list);
+ entry->irq = 0;
entry->dev = NULL;
return entry;
@@ -256,7 +254,6 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
static void __pci_restore_msix_state(struct pci_dev *dev)
{
int pos;
- int irq, head, tail = 0;
struct msi_desc *entry;
u16 control;
@@ -266,18 +263,15 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
/* route the table */
pci_intx(dev, 0); /* disable intx */
msix_set_enable(dev, 0);
- irq = head = dev->first_msi_irq;
- entry = get_irq_msi(irq);
- pos = entry->msi_attrib.pos;
- while (head != tail) {
- entry = get_irq_msi(irq);
- write_msi_msg(irq, &entry->msg);
- msi_set_mask_bit(irq, entry->msi_attrib.masked);
- tail = entry->link.tail;
- irq = tail;
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ write_msi_msg(entry->irq, &entry->msg);
+ msi_set_mask_bit(entry->irq, entry->msi_attrib.masked);
}
+ BUG_ON(list_empty(&dev->msi_list));
+ entry = list_entry(dev->msi_list.next, struct msi_desc, list);
+ pos = entry->msi_attrib.pos;
pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
control &= ~PCI_MSIX_FLAGS_MASKALL;
control |= PCI_MSIX_FLAGS_ENABLE;
@@ -303,7 +297,7 @@ void pci_restore_msi_state(struct pci_dev *dev)
static int msi_capability_init(struct pci_dev *dev)
{
struct msi_desc *entry;
- int pos, irq;
+ int pos, ret;
u16 control;
msi_set_enable(dev, 0); /* Ensure msi is disabled as I set it up */
@@ -340,23 +334,21 @@ static int msi_capability_init(struct pci_dev *dev)
msi_mask_bits_reg(pos, is_64bit_address(control)),
maskbits);
}
+ list_add(&entry->list, &dev->msi_list);
+
/* Configure MSI capability structure */
- irq = arch_setup_msi_irq(dev, entry);
- if (irq < 0) {
- kmem_cache_free(msi_cachep, entry);
- return irq;
+ ret = arch_setup_msi_irqs(dev, 1, PCI_CAP_ID_MSI);
+ if (ret) {
+ msi_free_irqs(dev);
+ return ret;
}
- entry->link.head = irq;
- entry->link.tail = irq;
- dev->first_msi_irq = irq;
- set_irq_msi(irq, entry);
/* Set MSI enabled bits */
pci_intx(dev, 0); /* disable intx */
msi_set_enable(dev, 1);
dev->msi_enabled = 1;
- dev->irq = irq;
+ dev->irq = entry->irq;
return 0;
}
@@ -373,8 +365,8 @@ static int msi_capability_init(struct pci_dev *dev)
static int msix_capability_init(struct pci_dev *dev,
struct msix_entry *entries, int nvec)
{
- struct msi_desc *head = NULL, *tail = NULL, *entry = NULL;
- int irq, pos, i, j, nr_entries, temp = 0;
+ struct msi_desc *entry;
+ int pos, i, j, nr_entries, ret;
unsigned long phys_addr;
u32 table_offset;
u16 control;
@@ -413,44 +405,34 @@ static int msix_capability_init(struct pci_dev *dev,
entry->dev = dev;
entry->mask_base = base;
- /* Configure MSI-X capability structure */
- irq = arch_setup_msi_irq(dev, entry);
- if (irq < 0) {
- kmem_cache_free(msi_cachep, entry);
- break;
- }
- entries[i].vector = irq;
- if (!head) {
- entry->link.head = irq;
- entry->link.tail = irq;
- head = entry;
- } else {
- entry->link.head = temp;
- entry->link.tail = tail->link.tail;
- tail->link.tail = irq;
- head->link.head = irq;
- }
- temp = irq;
- tail = entry;
-
- set_irq_msi(irq, entry);
+ list_add(&entry->list, &dev->msi_list);
}
- if (i != nvec) {
- int avail = i - 1;
- i--;
- for (; i >= 0; i--) {
- irq = (entries + i)->vector;
- msi_free_irq(dev, irq);
- (entries + i)->vector = 0;
+
+ ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSIX);
+ if (ret) {
+ int avail = 0;
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ if (entry->irq != 0) {
+ avail++;
+ }
}
+
+ msi_free_irqs(dev);
+
/* If we had some success report the number of irqs
* we succeeded in setting up.
*/
- if (avail <= 0)
- avail = -EBUSY;
+ if (avail == 0)
+ avail = ret;
return avail;
}
- dev->first_msi_irq = entries[0].vector;
+
+ i = 0;
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ entries[i].vector = entry->irq;
+ set_irq_msi(entry->irq, entry);
+ i++;
+ }
/* Set MSI-X enabled bits */
pci_intx(dev, 0); /* disable intx */
msix_set_enable(dev, 1);
@@ -460,21 +442,32 @@ static int msix_capability_init(struct pci_dev *dev,
}
/**
- * pci_msi_supported - check whether MSI may be enabled on device
+ * pci_msi_check_device - check whether MSI may be enabled on a device
* @dev: pointer to the pci_dev data structure of MSI device function
+ * @nvec: how many MSIs have been requested ?
+ * @type: are we checking for MSI or MSI-X ?
*
* Look at global flags, the device itself, and its parent busses
- * to return 0 if MSI are supported for the device.
+ * to determine if MSI/-X are supported for the device. If MSI/-X is
+ * supported return 0, else return an error code.
**/
-static
-int pci_msi_supported(struct pci_dev * dev)
+static int pci_msi_check_device(struct pci_dev* dev, int nvec, int type)
{
struct pci_bus *bus;
+ int ret;
/* MSI must be globally enabled and supported by the device */
if (!pci_msi_enable || !dev || dev->no_msi)
return -EINVAL;
+ /*
+ * You can't ask to have 0 or less MSIs configured.
+ * a) it's stupid ..
+ * b) the list manipulation code assumes nvec >= 1.
+ */
+ if (nvec < 1)
+ return -ERANGE;
+
/* Any bridge which does NOT route MSI transactions from it's
* secondary bus to it's primary bus must set NO_MSI flag on
* the secondary pci_bus.
@@ -485,6 +478,13 @@ int pci_msi_supported(struct pci_dev * dev)
if (bus->bus_flags & PCI_BUS_FLAGS_NO_MSI)
return -EINVAL;
+ ret = arch_msi_check_device(dev, nvec, type);
+ if (ret)
+ return ret;
+
+ if (!pci_find_capability(dev, type))
+ return -EINVAL;
+
return 0;
}
@@ -500,19 +500,12 @@ int pci_msi_supported(struct pci_dev * dev)
**/
int pci_enable_msi(struct pci_dev* dev)
{
- int pos, status;
-
- if (pci_msi_supported(dev) < 0)
- return -EINVAL;
+ int status;
- status = msi_init();
- if (status < 0)
+ status = pci_msi_check_device(dev, 1, PCI_CAP_ID_MSI);
+ if (status)
return status;
- pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
- if (!pos)
- return -EINVAL;
-
WARN_ON(!!dev->msi_enabled);
/* Check whether driver already requested for MSI-X irqs */
@@ -525,69 +518,54 @@ int pci_enable_msi(struct pci_dev* dev)
status = msi_capability_init(dev);
return status;
}
+EXPORT_SYMBOL(pci_enable_msi);
void pci_disable_msi(struct pci_dev* dev)
{
struct msi_desc *entry;
int default_irq;
- if (!pci_msi_enable)
- return;
- if (!dev)
- return;
-
- if (!dev->msi_enabled)
+ if (!pci_msi_enable || !dev || !dev->msi_enabled)
return;
msi_set_enable(dev, 0);
pci_intx(dev, 1); /* enable intx */
dev->msi_enabled = 0;
- entry = get_irq_msi(dev->first_msi_irq);
- if (!entry || !entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
+ BUG_ON(list_empty(&dev->msi_list));
+ entry = list_entry(dev->msi_list.next, struct msi_desc, list);
+ if (!entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
return;
}
- if (irq_has_action(dev->first_msi_irq)) {
- printk(KERN_WARNING "PCI: %s: pci_disable_msi() called without "
- "free_irq() on MSI irq %d\n",
- pci_name(dev), dev->first_msi_irq);
- BUG_ON(irq_has_action(dev->first_msi_irq));
- } else {
- default_irq = entry->msi_attrib.default_irq;
- msi_free_irq(dev, dev->first_msi_irq);
-
- /* Restore dev->irq to its default pin-assertion irq */
- dev->irq = default_irq;
- }
- dev->first_msi_irq = 0;
+
+ default_irq = entry->msi_attrib.default_irq;
+ msi_free_irqs(dev);
+
+ /* Restore dev->irq to its default pin-assertion irq */
+ dev->irq = default_irq;
}
+EXPORT_SYMBOL(pci_disable_msi);
-static int msi_free_irq(struct pci_dev* dev, int irq)
+static int msi_free_irqs(struct pci_dev* dev)
{
- struct msi_desc *entry;
- int head, entry_nr, type;
- void __iomem *base;
+ struct msi_desc *entry, *tmp;
- entry = get_irq_msi(irq);
- if (!entry || entry->dev != dev) {
- return -EINVAL;
- }
- type = entry->msi_attrib.type;
- entry_nr = entry->msi_attrib.entry_nr;
- head = entry->link.head;
- base = entry->mask_base;
- get_irq_msi(entry->link.head)->link.tail = entry->link.tail;
- get_irq_msi(entry->link.tail)->link.head = entry->link.head;
-
- arch_teardown_msi_irq(irq);
- kmem_cache_free(msi_cachep, entry);
-
- if (type == PCI_CAP_ID_MSIX) {
- writel(1, base + entry_nr * PCI_MSIX_ENTRY_SIZE +
- PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
-
- if (head == irq)
- iounmap(base);
+ list_for_each_entry(entry, &dev->msi_list, list)
+ BUG_ON(irq_has_action(entry->irq));
+
+ arch_teardown_msi_irqs(dev);
+
+ list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
+ if (entry->msi_attrib.type == PCI_CAP_ID_MSIX) {
+ if (list_is_last(&entry->list, &dev->msi_list))
+ iounmap(entry->mask_base);
+
+ writel(1, entry->mask_base + entry->msi_attrib.entry_nr
+ * PCI_MSIX_ENTRY_SIZE
+ + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
+ }
+ list_del(&entry->list);
+ kfree(entry);
}
return 0;
@@ -614,17 +592,14 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
int i, j;
u16 control;
- if (!entries || pci_msi_supported(dev) < 0)
+ if (!entries)
return -EINVAL;
- status = msi_init();
- if (status < 0)
+ status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSIX);
+ if (status)
return status;
pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
- if (!pos)
- return -EINVAL;
-
pci_read_config_word(dev, msi_control_reg(pos), &control);
nr_entries = multi_msix_capable(control);
if (nvec > nr_entries)
@@ -651,41 +626,25 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
status = msix_capability_init(dev, entries, nvec);
return status;
}
+EXPORT_SYMBOL(pci_enable_msix);
-void pci_disable_msix(struct pci_dev* dev)
+static void msix_free_all_irqs(struct pci_dev *dev)
{
- int irq, head, tail = 0, warning = 0;
-
- if (!pci_msi_enable)
- return;
- if (!dev)
- return;
+ msi_free_irqs(dev);
+}
- if (!dev->msix_enabled)
+void pci_disable_msix(struct pci_dev* dev)
+{
+ if (!pci_msi_enable || !dev || !dev->msix_enabled)
return;
msix_set_enable(dev, 0);
pci_intx(dev, 1); /* enable intx */
dev->msix_enabled = 0;
- irq = head = dev->first_msi_irq;
- while (head != tail) {
- tail = get_irq_msi(irq)->link.tail;
- if (irq_has_action(irq))
- warning = 1;
- else if (irq != head) /* Release MSI-X irq */
- msi_free_irq(dev, irq);
- irq = tail;
- }
- msi_free_irq(dev, irq);
- if (warning) {
- printk(KERN_WARNING "PCI: %s: pci_disable_msix() called without "
- "free_irq() on all MSI-X irqs\n",
- pci_name(dev));
- BUG_ON(warning > 0);
- }
- dev->first_msi_irq = 0;
+ msix_free_all_irqs(dev);
}
+EXPORT_SYMBOL(pci_disable_msix);
/**
* msi_remove_pci_irq_vectors - reclaim MSI(X) irqs to unused state
@@ -701,38 +660,11 @@ void msi_remove_pci_irq_vectors(struct pci_dev* dev)
if (!pci_msi_enable || !dev)
return;
- if (dev->msi_enabled) {
- if (irq_has_action(dev->first_msi_irq)) {
- printk(KERN_WARNING "PCI: %s: msi_remove_pci_irq_vectors() "
- "called without free_irq() on MSI irq %d\n",
- pci_name(dev), dev->first_msi_irq);
- BUG_ON(irq_has_action(dev->first_msi_irq));
- } else /* Release MSI irq assigned to this device */
- msi_free_irq(dev, dev->first_msi_irq);
- }
- if (dev->msix_enabled) {
- int irq, head, tail = 0, warning = 0;
- void __iomem *base = NULL;
-
- irq = head = dev->first_msi_irq;
- while (head != tail) {
- tail = get_irq_msi(irq)->link.tail;
- base = get_irq_msi(irq)->mask_base;
- if (irq_has_action(irq))
- warning = 1;
- else if (irq != head) /* Release MSI-X irq */
- msi_free_irq(dev, irq);
- irq = tail;
- }
- msi_free_irq(dev, irq);
- if (warning) {
- iounmap(base);
- printk(KERN_WARNING "PCI: %s: msi_remove_pci_irq_vectors() "
- "called without free_irq() on all MSI-X irqs\n",
- pci_name(dev));
- BUG_ON(warning > 0);
- }
- }
+ if (dev->msi_enabled)
+ msi_free_irqs(dev);
+
+ if (dev->msix_enabled)
+ msix_free_all_irqs(dev);
}
void pci_no_msi(void)
@@ -740,7 +672,53 @@ void pci_no_msi(void)
pci_msi_enable = 0;
}
-EXPORT_SYMBOL(pci_enable_msi);
-EXPORT_SYMBOL(pci_disable_msi);
-EXPORT_SYMBOL(pci_enable_msix);
-EXPORT_SYMBOL(pci_disable_msix);
+void pci_msi_init_pci_dev(struct pci_dev *dev)
+{
+ INIT_LIST_HEAD(&dev->msi_list);
+}
+
+
+/* Arch hooks */
+
+int __attribute__ ((weak))
+arch_msi_check_device(struct pci_dev* dev, int nvec, int type)
+{
+ return 0;
+}
+
+int __attribute__ ((weak))
+arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *entry)
+{
+ return 0;
+}
+
+int __attribute__ ((weak))
+arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+ struct msi_desc *entry;
+ int ret;
+
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ ret = arch_setup_msi_irq(dev, entry);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+void __attribute__ ((weak)) arch_teardown_msi_irq(unsigned int irq)
+{
+ return;
+}
+
+void __attribute__ ((weak))
+arch_teardown_msi_irqs(struct pci_dev *dev)
+{
+ struct msi_desc *entry;
+
+ list_for_each_entry(entry, &dev->msi_list, list) {
+ if (entry->irq != 0)
+ arch_teardown_msi_irq(entry->irq);
+ }
+}
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