static int its_pci_msi_vec_count(struct pci_dev *pdev)
{
int msi, msix;
msi = max(pci_msi_vec_count(pdev), 0);
msix = max(pci_msix_vec_count(pdev), 0);
return max(msi, msix);
}
static int its_pci_msi_vec_count(struct pci_dev *pdev, void *data)
{
int msi, msix, *count = data;
msi = max(pci_msi_vec_count(pdev), 0);
msix = max(pci_msix_vec_count(pdev), 0);
*count += max(msi, msix);
return 0;
}
static void qib_msix_setup(struct qib_devdata *dd, int pos, u32 *msixcnt,
struct qib_msix_entry *qib_msix_entry)
{
int ret;
int nvec = *msixcnt;
struct msix_entry *msix_entry;
int i;
ret = pci_msix_vec_count(dd->pcidev);
if (ret < 0)
goto do_intx;
nvec = min(nvec, ret);
/* We can't pass qib_msix_entry array to qib_msix_setup
* so use a dummy msix_entry array and copy the allocated
* irq back to the qib_msix_entry array. */
msix_entry = kcalloc(nvec, sizeof(*msix_entry), GFP_KERNEL);
if (!msix_entry)
goto do_intx;
for (i = 0; i < nvec; i++)
msix_entry[i] = qib_msix_entry[i].msix;
ret = pci_enable_msix_range(dd->pcidev, msix_entry, 1, nvec);
if (ret < 0)
goto free_msix_entry;
else
nvec = ret;
for (i = 0; i < nvec; i++)
qib_msix_entry[i].msix = msix_entry[i];
kfree(msix_entry);
*msixcnt = nvec;
return;
free_msix_entry:
kfree(msix_entry);
do_intx:
qib_dev_err(
dd,
"pci_enable_msix_range %d vectors failed: %d, falling back to INTx\n",
nvec, ret);
*msixcnt = 0;
qib_enable_intx(dd->pcidev);
}
/**
* pcie_port_enable_msix - try to set up MSI-X as interrupt mode for given port
* @dev: PCI Express port to handle
* @vectors: Array of interrupt vectors to populate
* @mask: Bitmask of port capabilities returned by get_port_device_capability()
*
* Return value: 0 on success, error code on failure
*/
static int pcie_port_enable_msix(struct pci_dev *dev, int *vectors, int mask)
{
struct msix_entry *msix_entries;
int idx[PCIE_PORT_DEVICE_MAXSERVICES];
int nr_entries, status, pos, i, nvec;
u16 reg16;
u32 reg32;
nr_entries = pci_msix_vec_count(dev);
if (nr_entries < 0)
return nr_entries;
BUG_ON(!nr_entries);
if (nr_entries > PCIE_PORT_MAX_MSIX_ENTRIES)
nr_entries = PCIE_PORT_MAX_MSIX_ENTRIES;
msix_entries = kzalloc(sizeof(*msix_entries) * nr_entries, GFP_KERNEL);
if (!msix_entries)
return -ENOMEM;
/*
* Allocate as many entries as the port wants, so that we can check
* which of them will be useful. Moreover, if nr_entries is correctly
* equal to the number of entries this port actually uses, we'll happily
* go through without any tricks.
*/
for (i = 0; i < nr_entries; i++)
msix_entries[i].entry = i;
status = pci_enable_msix_exact(dev, msix_entries, nr_entries);
if (status)
goto Exit;
for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++)
idx[i] = -1;
status = -EIO;
nvec = 0;
if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP)) {
int entry;
/*
* The code below follows the PCI Express Base Specification 2.0
* stating in Section 6.1.6 that "PME and Hot-Plug Event
* interrupts (when both are implemented) always share the same
* MSI or MSI-X vector, as indicated by the Interrupt Message
* Number field in the PCI Express Capabilities register", where
* according to Section 7.8.2 of the specification "For MSI-X,
* the value in this field indicates which MSI-X Table entry is
* used to generate the interrupt message."
*/
pcie_capability_read_word(dev, PCI_EXP_FLAGS, ®16);
entry = (reg16 & PCI_EXP_FLAGS_IRQ) >> 9;
if (entry >= nr_entries)
goto Error;
i = pcie_port_msix_add_entry(msix_entries, entry, nvec);
if (i == nvec)
nvec++;
idx[PCIE_PORT_SERVICE_PME_SHIFT] = i;
idx[PCIE_PORT_SERVICE_HP_SHIFT] = i;
}
