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path: root/drivers/pci/msi.c
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Diffstat (limited to 'drivers/pci/msi.c')
-rw-r--r--drivers/pci/msi.c100
1 files changed, 51 insertions, 49 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 362773247fbf..d9f06fbfa0bf 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -75,22 +75,17 @@ void arch_teardown_msi_irqs(struct pci_dev *dev)
}
#endif
-static void __msi_set_enable(struct pci_dev *dev, int pos, int enable)
+static void msi_set_enable(struct pci_dev *dev, int pos, int enable)
{
u16 control;
- if (pos) {
- pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
- control &= ~PCI_MSI_FLAGS_ENABLE;
- if (enable)
- control |= PCI_MSI_FLAGS_ENABLE;
- pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
- }
-}
+ BUG_ON(!pos);
-static void msi_set_enable(struct pci_dev *dev, int enable)
-{
- __msi_set_enable(dev, pci_find_capability(dev, PCI_CAP_ID_MSI), enable);
+ pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
+ control &= ~PCI_MSI_FLAGS_ENABLE;
+ if (enable)
+ control |= PCI_MSI_FLAGS_ENABLE;
+ pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control);
}
static void msix_set_enable(struct pci_dev *dev, int enable)
@@ -131,9 +126,6 @@ static inline __attribute_const__ u32 msi_enabled_mask(u16 control)
* mask all MSI interrupts by clearing the MSI enable bit does not work
* reliably as devices without an INTx disable bit will then generate a
* level IRQ which will never be cleared.
- *
- * Returns 1 if it succeeded in masking the interrupt and 0 if the device
- * doesn't support MSI masking.
*/
static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag)
{
@@ -303,7 +295,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev)
pos = entry->msi_attrib.pos;
pci_intx_for_msi(dev, 0);
- msi_set_enable(dev, 0);
+ msi_set_enable(dev, pos, 0);
write_msi_msg(dev->irq, &entry->msg);
pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);
@@ -321,22 +313,22 @@ static void __pci_restore_msix_state(struct pci_dev *dev)
if (!dev->msix_enabled)
return;
+ 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);
/* route the table */
pci_intx_for_msi(dev, 0);
- msix_set_enable(dev, 0);
+ control |= PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL;
+ pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
list_for_each_entry(entry, &dev->msi_list, list) {
write_msi_msg(entry->irq, &entry->msg);
msix_mask_irq(entry, entry->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;
pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
}
@@ -365,9 +357,9 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
u16 control;
unsigned mask;
- msi_set_enable(dev, 0); /* Ensure msi is disabled as I set it up */
-
pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
+ msi_set_enable(dev, pos, 0); /* Disable MSI during set up */
+
pci_read_config_word(dev, msi_control_reg(pos), &control);
/* MSI Entry Initialization */
entry = alloc_msi_entry(dev);
@@ -381,7 +373,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */
entry->msi_attrib.pos = pos;
- entry->mask_pos = msi_mask_bits_reg(pos, entry->msi_attrib.is_64);
+ entry->mask_pos = msi_mask_reg(pos, entry->msi_attrib.is_64);
/* All MSIs are unmasked by default, Mask them all */
if (entry->msi_attrib.maskbit)
pci_read_config_dword(dev, entry->mask_pos, &entry->masked);
@@ -399,7 +391,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
/* Set MSI enabled bits */
pci_intx_for_msi(dev, 0);
- msi_set_enable(dev, 1);
+ msi_set_enable(dev, pos, 1);
dev->msi_enabled = 1;
dev->irq = entry->irq;
@@ -427,11 +419,14 @@ static int msix_capability_init(struct pci_dev *dev,
u8 bir;
void __iomem *base;
- msix_set_enable(dev, 0);/* Ensure msix is disabled as I set it up */
-
pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
+ pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control);
+
+ /* Ensure MSI-X is disabled while it is set up */
+ control &= ~PCI_MSIX_FLAGS_ENABLE;
+ pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+
/* 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);
@@ -442,7 +437,6 @@ static int msix_capability_init(struct pci_dev *dev,
if (base == NULL)
return -ENOMEM;
- /* MSI-X Table Initialization */
for (i = 0; i < nvec; i++) {
entry = alloc_msi_entry(dev);
if (!entry)
@@ -455,7 +449,6 @@ static int msix_capability_init(struct pci_dev *dev,
entry->msi_attrib.default_irq = dev->irq;
entry->msi_attrib.pos = pos;
entry->mask_base = base;
- msix_mask_irq(entry, 1);
list_add_tail(&entry->list, &dev->msi_list);
}
@@ -480,22 +473,31 @@ static int msix_capability_init(struct pci_dev *dev,
return ret;
}
+ /*
+ * Some devices require MSI-X to be enabled before we can touch the
+ * MSI-X registers. We need to mask all the vectors to prevent
+ * interrupts coming in before they're fully set up.
+ */
+ control |= PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE;
+ pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
+
i = 0;
list_for_each_entry(entry, &dev->msi_list, list) {
entries[i].vector = entry->irq;
set_irq_msi(entry->irq, entry);
+ j = entries[i].entry;
+ entry->masked = readl(base + j * PCI_MSIX_ENTRY_SIZE +
+ PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
+ msix_mask_irq(entry, 1);
i++;
}
- /* Set MSI-X enabled bits */
+
+ /* Set MSI-X enabled bits and unmask the function */
pci_intx_for_msi(dev, 0);
- msix_set_enable(dev, 1);
dev->msix_enabled = 1;
- list_for_each_entry(entry, &dev->msi_list, list) {
- int vector = entry->msi_attrib.entry_nr;
- entry->masked = readl(base + vector * PCI_MSIX_ENTRY_SIZE +
- PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
- }
+ control &= ~PCI_MSIX_FLAGS_MASKALL;
+ pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control);
return 0;
}
@@ -596,17 +598,20 @@ void pci_msi_shutdown(struct pci_dev *dev)
struct msi_desc *desc;
u32 mask;
u16 ctrl;
+ unsigned pos;
if (!pci_msi_enable || !dev || !dev->msi_enabled)
return;
- msi_set_enable(dev, 0);
+ BUG_ON(list_empty(&dev->msi_list));
+ desc = list_first_entry(&dev->msi_list, struct msi_desc, list);
+ pos = desc->msi_attrib.pos;
+
+ msi_set_enable(dev, pos, 0);
pci_intx_for_msi(dev, 1);
dev->msi_enabled = 0;
- BUG_ON(list_empty(&dev->msi_list));
- desc = list_first_entry(&dev->msi_list, struct msi_desc, list);
- pci_read_config_word(dev, desc->msi_attrib.pos + PCI_MSI_FLAGS, &ctrl);
+ pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &ctrl);
mask = msi_capable_mask(ctrl);
msi_mask_irq(desc, mask, ~mask);
@@ -648,10 +653,7 @@ static int msi_free_irqs(struct pci_dev* dev)
list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) {
if (entry->msi_attrib.is_msix) {
- writel(1, entry->mask_base + entry->msi_attrib.entry_nr
- * PCI_MSIX_ENTRY_SIZE
- + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
-
+ msix_mask_irq(entry, 1);
if (list_is_last(&entry->list, &dev->msi_list))
iounmap(entry->mask_base);
}
@@ -691,8 +693,8 @@ int pci_msix_table_size(struct pci_dev *dev)
* indicates the successful configuration of MSI-X capability structure
* with new allocated MSI-X irqs. A return of < 0 indicates a failure.
* Or a return of > 0 indicates that driver request is exceeding the number
- * of irqs available. Driver should use the returned value to re-send
- * its request.
+ * of irqs or MSI-X 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)
{
@@ -708,7 +710,7 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
nr_entries = pci_msix_table_size(dev);
if (nvec > nr_entries)
- return -EINVAL;
+ return nr_entries;
/* Check for any invalid entries */
for (i = 0; i < nvec; i++) {
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-11 09:38:31 +0100