blob: 656cb772b6910458392cc2cc0c5001fced632189 [file] [log] [blame]
* Copyright 2007, Olof Johansson, PA Semi
* Based on arch/powerpc/sysdev/mpic_u3msi.c:
* 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.
#undef DEBUG
#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 <asm/msi_bitmap.h>
#include "mpic.h"
/* Allocate 16 interrupts per device, to give an alignment of 16,
* since that's the size of the grouping w.r.t. affinity. If someone
* needs more than 32 MSI's down the road we'll have to rethink this,
* but it should be OK for now.
#define ALLOC_CHUNK 16
#define PASEMI_MSI_ADDR 0xfc080000
/* A bit ugly, can we get this from the pci_dev somehow? */
static struct mpic *msi_mpic;
static void mpic_pasemi_msi_mask_irq(unsigned int irq)
pr_debug("mpic_pasemi_msi_mask_irq %d\n", irq);
static void mpic_pasemi_msi_unmask_irq(unsigned int irq)
pr_debug("mpic_pasemi_msi_unmask_irq %d\n", irq);
static struct irq_chip mpic_pasemi_msi_chip = {
.shutdown = mpic_pasemi_msi_mask_irq,
.mask = mpic_pasemi_msi_mask_irq,
.unmask = mpic_pasemi_msi_unmask_irq,
.eoi = mpic_end_irq,
.set_type = mpic_set_irq_type,
.set_affinity = mpic_set_affinity,
.typename = "PASEMI-MSI ",
static int pasemi_msi_check_device(struct pci_dev *pdev, int nvec, int type)
if (type == PCI_CAP_ID_MSIX)
pr_debug("pasemi_msi: MSI-X untested, trying anyway\n");
return 0;
static void pasemi_msi_teardown_msi_irqs(struct pci_dev *pdev)
struct msi_desc *entry;
pr_debug("pasemi_msi_teardown_msi_irqs, pdev %p\n", pdev);
list_for_each_entry(entry, &pdev->msi_list, list) {
if (entry->irq == NO_IRQ)
set_irq_msi(entry->irq, NULL);
virq_to_hw(entry->irq), ALLOC_CHUNK);
static int pasemi_msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
unsigned int virq;
struct msi_desc *entry;
struct msi_msg msg;
int hwirq;
pr_debug("pasemi_msi_setup_msi_irqs, pdev %p nvec %d type %d\n",
pdev, nvec, type);
msg.address_hi = 0;
msg.address_lo = PASEMI_MSI_ADDR;
list_for_each_entry(entry, &pdev->msi_list, list) {
/* Allocate 16 interrupts for now, since that's the grouping for
* affinity. This can be changed later if it turns out 32 is too
* few MSIs for someone, but restrictions will apply to how the
* sources can be changed independently.
hwirq = msi_bitmap_alloc_hwirqs(&msi_mpic->msi_bitmap,
if (hwirq < 0) {
pr_debug("pasemi_msi: failed allocating hwirq\n");
return hwirq;
virq = irq_create_mapping(msi_mpic->irqhost, hwirq);
if (virq == NO_IRQ) {
pr_debug("pasemi_msi: failed mapping hwirq 0x%x\n",
msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq,
return -ENOSPC;
/* Vector on MSI is really an offset, the hardware adds
* it to the value written at the magic address. So set
* it to 0 to remain sane.
mpic_set_vector(virq, 0);
set_irq_msi(virq, entry);
set_irq_chip(virq, &mpic_pasemi_msi_chip);
set_irq_type(virq, IRQ_TYPE_EDGE_RISING);
pr_debug("pasemi_msi: allocated virq 0x%x (hw 0x%x) " \
"addr 0x%x\n", virq, hwirq, msg.address_lo);
/* Likewise, the device writes [0...511] into the target
* register to generate MSI [512...1023]
*/ = hwirq-0x200;
write_msi_msg(virq, &msg);
return 0;
int mpic_pasemi_msi_init(struct mpic *mpic)
int rc;
if (!mpic->irqhost->of_node ||
return -ENODEV;
rc = mpic_msi_init_allocator(mpic);
if (rc) {
pr_debug("pasemi_msi: Error allocating bitmap!\n");
return rc;
pr_debug("pasemi_msi: Registering PA Semi MPIC MSI callbacks\n");
msi_mpic = mpic;
ppc_md.setup_msi_irqs = pasemi_msi_setup_msi_irqs;
ppc_md.teardown_msi_irqs = pasemi_msi_teardown_msi_irqs;
ppc_md.msi_check_device = pasemi_msi_check_device;
return 0;