This is very similar to the MSI domains of the pSeries platform. The
MSI allocator is directly handled under the Linux PHB in the
in-the-middle "PNV-MSI" domain.
Only the XIVE (P9/P10) parent domain is supported for now. Support for
XICS will come later.
Signed-off-by: Cédric Le Goater <c...@kaod.org>
---
arch/powerpc/platforms/powernv/pci-ioda.c | 188 ++++++++++++++++++++++
1 file changed, 188 insertions(+)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c
b/arch/powerpc/platforms/powernv/pci-ioda.c
index 2922674cc934..d2a17fcb6002 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -36,6 +36,7 @@
#include <asm/firmware.h>
#include <asm/pnv-pci.h>
#include <asm/mmzone.h>
+#include <asm/xive.h>
#include <misc/cxl-base.h>
@@ -2100,6 +2101,189 @@ static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb,
struct pci_dev *dev,
return 0;
}
+/*
+ * The msi_free() op is called before irq_domain_free_irqs_top() when
+ * the handler data is still available. Use that to clear the XIVE
+ * controller.
+ */
+static void pnv_msi_ops_msi_free(struct irq_domain *domain,
+ struct msi_domain_info *info,
+ unsigned int irq)
+{
+ if (xive_enabled())
+ xive_irq_free_data(irq);
+}
+
+static struct msi_domain_ops pnv_pci_msi_domain_ops = {
+ .msi_free = pnv_msi_ops_msi_free,
+};
+
+static void pnv_msi_shutdown(struct irq_data *d)
+{
+ d = d->parent_data;
+ if (d->chip->irq_shutdown)
+ d->chip->irq_shutdown(d);
+}
+
+static void pnv_msi_mask(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void pnv_msi_unmask(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip pnv_pci_msi_irq_chip = {
+ .name = "PNV-PCI-MSI",
+ .irq_shutdown = pnv_msi_shutdown,
+ .irq_mask = pnv_msi_mask,
+ .irq_unmask = pnv_msi_unmask,
+ .irq_eoi = irq_chip_eoi_parent,
+};
+
+static struct msi_domain_info pnv_msi_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
+ .ops = &pnv_pci_msi_domain_ops,
+ .chip = &pnv_pci_msi_irq_chip,
+};
+
+static void pnv_msi_compose_msg(struct irq_data *d, struct msi_msg *msg)
+{
+ struct msi_desc *entry = irq_data_get_msi_desc(d);
+ struct pci_dev *pdev = msi_desc_to_pci_dev(entry);
+ struct pci_controller *hose = irq_data_get_irq_chip_data(d);
+ struct pnv_phb *phb = hose->private_data;
+ int rc;
+
+ rc = __pnv_pci_ioda_msi_setup(phb, pdev, d->hwirq,
+ entry->msi_attrib.is_64, msg);
+ if (rc)
+ dev_err(&pdev->dev, "Failed to setup %s-bit MSI #%ld : %d\n",
+ entry->msi_attrib.is_64 ? "64" : "32", d->hwirq, rc);
+}
+
+static struct irq_chip pnv_msi_irq_chip = {
+ .name = "PNV-MSI",
+ .irq_shutdown = pnv_msi_shutdown,
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+ .irq_compose_msi_msg = pnv_msi_compose_msg,
+};
+
+static int pnv_irq_parent_domain_alloc(struct irq_domain *domain,
+ unsigned int virq, int hwirq)
+{
+ struct irq_fwspec parent_fwspec;
+ int ret;
+
+ parent_fwspec.fwnode = domain->parent->fwnode;
+ parent_fwspec.param_count = 2;
+ parent_fwspec.param[0] = hwirq;
+ parent_fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static int pnv_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct pci_controller *hose = domain->host_data;
+ struct pnv_phb *phb = hose->private_data;
+ msi_alloc_info_t *info = arg;
+ struct pci_dev *pdev = msi_desc_to_pci_dev(info->desc);
+ int hwirq;
+ int i, ret;
+
+ hwirq = msi_bitmap_alloc_hwirqs(&phb->msi_bmp, nr_irqs);
+ if (hwirq < 0) {
+ dev_warn(&pdev->dev, "failed to find a free MSI\n");
+ return -ENOSPC;
+ }
+
+ dev_dbg(&pdev->dev, "%s bridge %pOF %d/%x #%d\n", __func__,
+ hose->dn, virq, hwirq, nr_irqs);
+
+ for (i = 0; i < nr_irqs; i++) {
+ ret = pnv_irq_parent_domain_alloc(domain, virq + i,
+ phb->msi_base + hwirq + i);
+ if (ret)
+ goto out;
+
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &pnv_msi_irq_chip, hose);
+ }
+
+ return 0;
+
+out:
+ irq_domain_free_irqs_parent(domain, virq, i - 1);
+ msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, nr_irqs);
+ return ret;
+}
+
+static void pnv_irq_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+ struct pci_controller *hose = irq_data_get_irq_chip_data(d);
+ struct pnv_phb *phb = hose->private_data;
+
+ pr_debug("%s bridge %pOF %d/%lx #%d\n", __func__, hose->dn,
+ virq, d->hwirq, nr_irqs);
+
+ msi_bitmap_free_hwirqs(&phb->msi_bmp, d->hwirq, nr_irqs);
+ /* XIVE domain is cleared through ->msi_free() */
+}
+
+static const struct irq_domain_ops pnv_irq_domain_ops = {
+ .alloc = pnv_irq_domain_alloc,
+ .free = pnv_irq_domain_free,
+};
+
+static int pnv_msi_allocate_domains(struct pci_controller *hose, unsigned int
count)
+{
+ struct pnv_phb *phb = hose->private_data;
+ struct irq_domain *parent = irq_get_default_host();
+
+ hose->fwnode = irq_domain_alloc_named_id_fwnode("PNV-MSI",
phb->opal_id);
+ if (!hose->fwnode)
+ return -ENOMEM;
+
+ hose->dev_domain = irq_domain_create_hierarchy(parent, 0, count,
+ hose->fwnode,
+ &pnv_irq_domain_ops,
hose);
+ if (!hose->dev_domain) {
+ pr_err("PCI: failed to create IRQ domain bridge %pOF (domain
%d)\n",
+ hose->dn, hose->global_number);
+ irq_domain_free_fwnode(hose->fwnode);
+ return -ENOMEM;
+ }
+
+ hose->msi_domain =
pci_msi_create_irq_domain(of_node_to_fwnode(hose->dn),
+ &pnv_msi_domain_info,
+ hose->dev_domain);
+ if (!hose->msi_domain) {
+ pr_err("PCI: failed to create MSI IRQ domain bridge %pOF
(domain %d)\n",
+ hose->dn, hose->global_number);
+ irq_domain_free_fwnode(hose->fwnode);
+ irq_domain_remove(hose->dev_domain);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
static void pnv_pci_init_ioda_msis(struct pnv_phb *phb)
{
unsigned int count;
@@ -2124,6 +2308,10 @@ static void pnv_pci_init_ioda_msis(struct pnv_phb *phb)
phb->msi32_support = 1;
pr_info(" Allocated bitmap for %d MSIs (base IRQ 0x%x)\n",
count, phb->msi_base);
+
+ /* Only supported by the XIVE driver */
+ if (xive_enabled())
+ pnv_msi_allocate_domains(phb->hose, count);
}
static void pnv_ioda_setup_pe_res(struct pnv_ioda_pe *pe,
--
2.31.1
