diff options
Diffstat (limited to 'arch/powerpc/sysdev/mpic_u3msi.c')
| -rw-r--r-- | arch/powerpc/sysdev/mpic_u3msi.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/mpic_u3msi.c b/arch/powerpc/sysdev/mpic_u3msi.c new file mode 100644 index 00000000000..305b864c25d --- /dev/null +++ b/arch/powerpc/sysdev/mpic_u3msi.c @@ -0,0 +1,186 @@ +/* + * Copyright 2006, Segher Boessenkool, IBM Corporation. + * Copyright 2006-2007, Michael Ellerman, IBM Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; version 2 of the + * License. + * + */ + +#include <linux/irq.h> +#include <linux/bootmem.h> +#include <linux/msi.h> +#include <asm/mpic.h> +#include <asm/prom.h> +#include <asm/hw_irq.h> +#include <asm/ppc-pci.h> + +#include "mpic.h" + +/* A bit ugly, can we get this from the pci_dev somehow? */ +static struct mpic *msi_mpic; + +static void mpic_u3msi_mask_irq(unsigned int irq) +{ + mask_msi_irq(irq); + mpic_mask_irq(irq); +} + +static void mpic_u3msi_unmask_irq(unsigned int irq) +{ + mpic_unmask_irq(irq); + unmask_msi_irq(irq); +} + +static struct irq_chip mpic_u3msi_chip = { + .shutdown = mpic_u3msi_mask_irq, + .mask = mpic_u3msi_mask_irq, + .unmask = mpic_u3msi_unmask_irq, + .eoi = mpic_end_irq, + .set_type = mpic_set_irq_type, + .typename = "MPIC-U3MSI", +}; + +static u64 read_ht_magic_addr(struct pci_dev *pdev, unsigned int pos) +{ + u8 flags; + u32 tmp; + u64 addr; + + pci_read_config_byte(pdev, pos + HT_MSI_FLAGS, &flags); + + if (flags & HT_MSI_FLAGS_FIXED) + return HT_MSI_FIXED_ADDR; + + pci_read_config_dword(pdev, pos + HT_MSI_ADDR_LO, &tmp); + addr = tmp & HT_MSI_ADDR_LO_MASK; + pci_read_config_dword(pdev, pos + HT_MSI_ADDR_HI, &tmp); + addr = addr | ((u64)tmp << 32); + + return addr; +} + +static u64 find_ht_magic_addr(struct pci_dev *pdev) +{ + struct pci_bus *bus; + unsigned int pos; + + for (bus = pdev->bus; bus; bus = bus->parent) { + pos = pci_find_ht_capability(bus->self, HT_CAPTYPE_MSI_MAPPING); + if (pos) + return read_ht_magic_addr(bus->self, pos); + } + + return 0; +} + +static int u3msi_msi_check_device(struct pci_dev *pdev, int nvec, int type) +{ + if (type == PCI_CAP_ID_MSIX) + pr_debug("u3msi: MSI-X untested, trying anyway.\n"); + + /* If we can't find a magic address then MSI ain't gonna work */ + if (find_ht_magic_addr(pdev) == 0) { + pr_debug("u3msi: no magic address found for %s\n", + pci_name(pdev)); + return -ENXIO; + } + + return 0; +} + +static void u3msi_teardown_msi_irqs(struct pci_dev *pdev) +{ + struct msi_desc *entry; + + list_for_each_entry(entry, &pdev->msi_list, list) { + if (entry->irq == NO_IRQ) + continue; + + set_irq_msi(entry->irq, NULL); + mpic_msi_free_hwirqs(msi_mpic, virq_to_hw(entry->irq), 1); + irq_dispose_mapping(entry->irq); + } + + return; +} + +static void u3msi_compose_msi_msg(struct pci_dev *pdev, int virq, + struct msi_msg *msg) +{ + u64 addr; + + addr = find_ht_magic_addr(pdev); + msg->address_lo = addr & 0xFFFFFFFF; + msg->address_hi = addr >> 32; + msg->data = virq_to_hw(virq); + + pr_debug("u3msi: allocated virq 0x%x (hw 0x%lx) at address 0x%lx\n", + virq, virq_to_hw(virq), addr); +} + +static int u3msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type) +{ + irq_hw_number_t hwirq; + int rc; + unsigned int virq; + struct msi_desc *entry; + struct msi_msg msg; + + list_for_each_entry(entry, &pdev->msi_list, list) { + hwirq = mpic_msi_alloc_hwirqs(msi_mpic, 1); + if (hwirq < 0) { + rc = hwirq; + pr_debug("u3msi: failed allocating hwirq\n"); + goto out_free; + } + + virq = irq_create_mapping(msi_mpic->irqhost, hwirq); + if (virq == NO_IRQ) { + pr_debug("u3msi: failed mapping hwirq 0x%lx\n", hwirq); + mpic_msi_free_hwirqs(msi_mpic, hwirq, 1); + rc = -ENOSPC; + goto out_free; + } + + set_irq_msi(virq, entry); + set_irq_chip(virq, &mpic_u3msi_chip); + set_irq_type(virq, IRQ_TYPE_EDGE_RISING); + + u3msi_compose_msi_msg(pdev, virq, &msg); + write_msi_msg(virq, &msg); + + hwirq++; + } + + return 0; + + out_free: + u3msi_teardown_msi_irqs(pdev); + return rc; +} + +int mpic_u3msi_init(struct mpic *mpic) +{ + int rc; + + rc = mpic_msi_init_allocator(mpic); + if (rc) { + pr_debug("u3msi: Error allocating bitmap!\n"); + return rc; + } + + pr_debug("u3msi: Registering MPIC U3 MSI callbacks.\n"); + + BUG_ON(msi_mpic); + msi_mpic = mpic; + + WARN_ON(ppc_md.setup_msi_irqs); + ppc_md.setup_msi_irqs = u3msi_setup_msi_irqs; + ppc_md.teardown_msi_irqs = u3msi_teardown_msi_irqs; + ppc_md.msi_check_device = u3msi_msi_check_device; + + return 0; +} |