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>
This commit is contained in:
Benjamin Herrenschmidt
2011-09-19 17:45:06 +00:00
parent 61305a96fa
commit c1a2562ac5
3 changed files with 168 additions and 0 deletions

View File

@@ -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 @@ void __init pnv_pci_init(void)
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
}