Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * 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,

        .set_affinity   = mpic_set_affinity,

        .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 int u3msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)

{

        irq_hw_number_t hwirq;

        unsigned int virq;

        struct msi_desc *entry;

        struct msi_msg msg;

        u64 addr;

        addr = find_ht_magic_addr(pdev);

        msg.address_lo = addr & 0xFFFFFFFF;

        msg.address_hi = addr >> 32;

        list_for_each_entry(entry, &pdev->msi_list, list) {

                hwirq = mpic_msi_alloc_hwirqs(msi_mpic, 1);

                if (hwirq < 0) {

                        pr_debug("u3msi: failed allocating hwirq\n");

                        return hwirq;

                }

                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);

                        return -ENOSPC;

                }

                set_irq_msi(virq, entry);

                set_irq_chip(virq, &mpic_u3msi_chip);

                set_irq_type(virq, IRQ_TYPE_EDGE_RISING);

                pr_debug("u3msi: allocated virq 0x%x (hw 0x%lx) addr 0x%lx\n",

                          virq, hwirq, addr);

                msg.data = hwirq;

                write_msi_msg(virq, &msg);

                hwirq++;

        }

        return 0;

}

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;

}