int
pci_intr_alloc(const struct pci_attach_args *pa, pci_intr_handle_t **ihps,
int *counts, pci_intr_type_t max_type)
{
if (counts != NULL && counts[PCI_INTR_TYPE_INTX] == 0)
return EINVAL;
return pci_intx_alloc(pa, ihps);
}
/*
* Interrupt handler allocation utility. This function calls each allocation
* function as specified by arguments.
* Currently callee functions are pci_intx_alloc(), pci_msi_alloc_exact(),
* and pci_msix_alloc_exact().
* pa : pci_attach_args
* ihps : interrupt handlers
* counts : The array of number of required interrupt handlers.
* It is overwritten by allocated the number of handlers.
* CAUTION: The size of counts[] must be PCI_INTR_TYPE_SIZE.
* max_type : "max" type of using interrupts. See below.
* e.g.
* If you want to use 5 MSI-X, 1 MSI, or INTx, you use "counts" as
* int counts[PCI_INTR_TYPE_SIZE];
* counts[PCI_INTR_TYPE_MSIX] = 5;
* counts[PCI_INTR_TYPE_MSI] = 1;
* counts[PCI_INTR_TYPE_INTX] = 1;
* error = pci_intr_alloc(pa, ihps, counts, PCI_INTR_TYPE_MSIX);
*
* If you want to use hardware max number MSI-X or 1 MSI,
* and not to use INTx, you use "counts" as
* int counts[PCI_INTR_TYPE_SIZE];
* counts[PCI_INTR_TYPE_MSIX] = -1;
* counts[PCI_INTR_TYPE_MSI] = 1;
* counts[PCI_INTR_TYPE_INTX] = 0;
* error = pci_intr_alloc(pa, ihps, counts, PCI_INTR_TYPE_MSIX);
*
* If you want to use 3 MSI or INTx, you can use "counts" as
* int counts[PCI_INTR_TYPE_SIZE];
* counts[PCI_INTR_TYPE_MSI] = 3;
* counts[PCI_INTR_TYPE_INTX] = 1;
* error = pci_intr_alloc(pa, ihps, counts, PCI_INTR_TYPE_MSI);
*
* If you want to use 1 MSI or INTx (probably most general usage),
* you can simply use this API like
* below
* error = pci_intr_alloc(pa, ihps, NULL, 0);
* ^ ignored
*/
int
pci_intr_alloc(const struct pci_attach_args *pa, pci_intr_handle_t **ihps,
int *counts, pci_intr_type_t max_type)
{
int error;
int intx_count, msi_count, msix_count;
intx_count = msi_count = msix_count = 0;
if (counts == NULL) { /* simple pattern */
msi_count = 1;
intx_count = 1;
} else {
switch(max_type) {
case PCI_INTR_TYPE_MSIX:
msix_count = counts[PCI_INTR_TYPE_MSIX];
/* FALLTHROUGH */
case PCI_INTR_TYPE_MSI:
msi_count = counts[PCI_INTR_TYPE_MSI];
/* FALLTHROUGH */
case PCI_INTR_TYPE_INTX:
intx_count = counts[PCI_INTR_TYPE_INTX];
break;
default:
return EINVAL;
}
}
if (counts != NULL)
memset(counts, 0, sizeof(counts[0]) * PCI_INTR_TYPE_SIZE);
error = EINVAL;
/* try MSI-X */
if (msix_count == -1) /* use hardware max */
msix_count = pci_msix_count(pa->pa_pc, pa->pa_tag);
if (msix_count > 0) {
error = pci_msix_alloc_exact(pa, ihps, msix_count);
if (error == 0) {
KASSERTMSG(counts != NULL,
"If MSI-X is used, counts must not be NULL.");
counts[PCI_INTR_TYPE_MSIX] = msix_count;
goto out;
}
}
/* try MSI */
if (msi_count == -1) /* use hardware max */
msi_count = pci_msi_count(pa->pa_pc, pa->pa_tag);
if (msi_count > 0) {
error = pci_msi_alloc_exact(pa, ihps, msi_count);
if (error == 0) {
if (counts != NULL)
counts[PCI_INTR_TYPE_MSI] = msi_count;
goto out;
}
}
/* try INTx */
if (intx_count != 0) { /* The number of INTx is always 1. */
error = pci_intx_alloc(pa, ihps);
if (error == 0) {
if (counts != NULL)
counts[PCI_INTR_TYPE_INTX] = 1;
}
}
out:
return error;
}
