powerpc/powernv: Implement MSI support for p5ioc2 PCIe
This implements support for MSIs on p5ioc2 PHBs. We only support
MSIs on the PCIe PHBs, not the PCI-X ones as the later hasn't been
properly verified in HW.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index 746ce5e..5c17551 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -19,6 +19,7 @@
#include <linux/bootmem.h>
#include <linux/irq.h>
#include <linux/io.h>
+#include <linux/msi.h>
#include <asm/sections.h>
#include <asm/io.h>
@@ -38,6 +39,108 @@
#define cfg_dbg(fmt...) do { } while(0)
//#define cfg_dbg(fmt...) printk(fmt)
+#ifdef CONFIG_PCI_MSI
+static int pnv_msi_check_device(struct pci_dev* pdev, int nvec, int type)
+{
+ struct pci_controller *hose = pci_bus_to_host(pdev->bus);
+ struct pnv_phb *phb = hose->private_data;
+
+ return (phb && phb->msi_map) ? 0 : -ENODEV;
+}
+
+static unsigned int pnv_get_one_msi(struct pnv_phb *phb)
+{
+ unsigned int id;
+
+ spin_lock(&phb->lock);
+ id = find_next_zero_bit(phb->msi_map, phb->msi_count, phb->msi_next);
+ if (id >= phb->msi_count && phb->msi_next)
+ id = find_next_zero_bit(phb->msi_map, phb->msi_count, 0);
+ if (id >= phb->msi_count) {
+ spin_unlock(&phb->lock);
+ return 0;
+ }
+ __set_bit(id, phb->msi_map);
+ spin_unlock(&phb->lock);
+ return id + phb->msi_base;
+}
+
+static void pnv_put_msi(struct pnv_phb *phb, unsigned int hwirq)
+{
+ unsigned int id;
+
+ if (WARN_ON(hwirq < phb->msi_base ||
+ hwirq >= (phb->msi_base + phb->msi_count)))
+ return;
+ id = hwirq - phb->msi_base;
+ spin_lock(&phb->lock);
+ __clear_bit(id, phb->msi_map);
+ spin_unlock(&phb->lock);
+}
+
+static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
+{
+ struct pci_controller *hose = pci_bus_to_host(pdev->bus);
+ struct pnv_phb *phb = hose->private_data;
+ struct msi_desc *entry;
+ struct msi_msg msg;
+ unsigned int hwirq, virq;
+ int rc;
+
+ if (WARN_ON(!phb))
+ return -ENODEV;
+
+ list_for_each_entry(entry, &pdev->msi_list, list) {
+ if (!entry->msi_attrib.is_64 && !phb->msi32_support) {
+ pr_warn("%s: Supports only 64-bit MSIs\n",
+ pci_name(pdev));
+ return -ENXIO;
+ }
+ hwirq = pnv_get_one_msi(phb);
+ if (!hwirq) {
+ pr_warn("%s: Failed to find a free MSI\n",
+ pci_name(pdev));
+ return -ENOSPC;
+ }
+ virq = irq_create_mapping(NULL, hwirq);
+ if (virq == NO_IRQ) {
+ pr_warn("%s: Failed to map MSI to linux irq\n",
+ pci_name(pdev));
+ pnv_put_msi(phb, hwirq);
+ return -ENOMEM;
+ }
+ rc = phb->msi_setup(phb, pdev, hwirq, entry->msi_attrib.is_64,
+ &msg);
+ if (rc) {
+ pr_warn("%s: Failed to setup MSI\n", pci_name(pdev));
+ irq_dispose_mapping(virq);
+ pnv_put_msi(phb, hwirq);
+ return rc;
+ }
+ irq_set_msi_desc(virq, entry);
+ write_msi_msg(virq, &msg);
+ }
+ return 0;
+}
+
+static void pnv_teardown_msi_irqs(struct pci_dev *pdev)
+{
+ struct pci_controller *hose = pci_bus_to_host(pdev->bus);
+ struct pnv_phb *phb = hose->private_data;
+ struct msi_desc *entry;
+
+ if (WARN_ON(!phb))
+ return;
+
+ list_for_each_entry(entry, &pdev->msi_list, list) {
+ if (entry->irq == NO_IRQ)
+ continue;
+ irq_set_msi_desc(entry->irq, NULL);
+ pnv_put_msi(phb, virq_to_hw(entry->irq));
+ irq_dispose_mapping(entry->irq);
+ }
+}
+#endif /* CONFIG_PCI_MSI */
static void pnv_pci_config_check_eeh(struct pnv_phb *phb, struct pci_bus *bus,
u32 bdfn)
@@ -283,4 +386,10 @@
ppc_md.tce_free = pnv_tce_free;
set_pci_dma_ops(&dma_iommu_ops);
+ /* Configure MSIs */
+#ifdef CONFIG_PCI_MSI
+ ppc_md.msi_check_device = pnv_msi_check_device;
+ ppc_md.setup_msi_irqs = pnv_setup_msi_irqs;
+ ppc_md.teardown_msi_irqs = pnv_teardown_msi_irqs;
+#endif
}