/*
* 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;
}
