/*
* 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/bitmap.h>
#include <linux/msi.h>
#include <asm/mpic.h>
#include <asm/prom.h>
#include <asm/hw_irq.h>
#include <asm/ppc-pci.h>
static void __mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
{
pr_debug("mpic: reserving hwirq 0x%lx\n", hwirq);
bitmap_allocate_region(mpic->hwirq_bitmap, hwirq, 0);
}
void mpic_msi_reserve_hwirq(struct mpic *mpic, irq_hw_number_t hwirq)
{
unsigned long flags;
/* The mpic calls this even when there is no allocator setup */
if (!mpic->hwirq_bitmap)
return;
spin_lock_irqsave(&mpic->bitmap_lock, flags);
__mpic_msi_reserve_hwirq(mpic, hwirq);
spin_unlock_irqrestore(&mpic->bitmap_lock, flags);
}
irq_hw_number_t mpic_msi_alloc_hwirqs(struct mpic *mpic, int num)
{
unsigned long flags;
int offset, order = get_count_order(num);
spin_lock_irqsave(&mpic->bitmap_lock, flags);
/*
* This is fast, but stricter than we need. We might want to add
* a fallback routine which does a linear search with no alignment.
*/
offset = bitmap_find_free_region(mpic->hwirq_bitmap, mpic->irq_count,
order);
spin_unlock_irqrestore(&mpic->bitmap_lock, flags);
pr_debug("mpic: allocated 0x%x (2^%d) at offset 0x%x\n",
num, order, offset);
return offset;
}
void mpic_msi_free_hwirqs(struct mpic *mpic, int offset, int num)
{
unsigned long flags;
int order = get_count_order(num);
pr_debug("mpic: freeing 0x%x (2^%d) at offset 0x%x\n",
num, order, offset);
spin_lock_irqsave(&mpic->bitmap_lock, flags);
bitmap_release_region(mpic->hwirq_bitmap, offset, order);
spin_unlock_irqrestore(&mpic->bitmap_lock, flags);
}
#ifdef CONFIG_MPIC_U3_HT_IRQS
static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
{
irq_hw_number_t hwirq;
struct irq_host_ops *ops = mpic->irqhost->ops;
struct device_node *np;
int flags, index, i;
struct of_irq oirq;
pr_debug("mpic: found U3, guessing msi allocator setup\n");
/* Reserve source numbers we know are reserved in the HW */
for (i = 0; i < 8; i++)
__mpic_msi_reserve_hwirq(mpic, i);
for (i = 42; i < 46; i++)
__mpic_msi_reserve_hwirq(mpic, i);
for (i = 100; i < 105; i++)
__mpic_msi_reserve_hwirq(mpic, i);
np = NULL;
while ((np = of_find_all_nodes(np))) {
pr_debug("mpic: mapping hwirqs for %s\n", np->full_name);
index = 0;
while (of_irq_map_one(np, index++, &oirq) == 0) {
ops->xlate(mpic->irqhost, NULL, oirq.specifier,
oirq.size, &hwirq, &flags);
__mpic_msi_reserve_hwirq(mpic, hwirq);
}
}
return 0;
}
#else
static int mpic_msi_reserve_u3_hwirqs(struct mpic *mpic)
{
return -1;
}
#endif
static int mpic_msi_reserve_dt_hwirqs(struct mpic *mpic)
{
int i, len;
const u32 *p;
p = of_get_property(mpic->of_node, "msi-available-ranges", &len);
if (!p) {
pr_debug("mpic: no msi-available-ranges property found on %s\n",
mpic->of_node->full_name);
return -ENODEV;
}
if (len % 8 != 0) {
printk(KERN_WARNING "mpic: Malformed msi-available-ranges "
"property on %s\n", mpic->of_node->full_name);
return -EINVAL;
}
bitmap_allocate_region(mpic->hwirq_bitmap, 0,
get_count_order(mpic->irq_count));
/* Format is: (<u32 start> <u32 count>)+ */
len /= sizeof(u32);
for (i = 0; i < len / 2; i++, p += 2)
mpic_msi_free_hwirqs(mpic, *p, *(p + 1));
return 0;
}
int mpic_msi_init_allocator(struct mpic *mpic)
{
int rc, size;
BUG_ON(mpic->hwirq_bitmap);
spin_lock_init(&mpic->bitmap_lock);
size = BITS_TO_LONGS(mpic->irq_count) * sizeof(long);
pr_debug("mpic: allocator bitmap size is 0x%x bytes\n", size);
if (mem_init_done)
mpic->hwirq_bitmap = kmalloc(size, GFP_KERNEL);
else
mpic->hwirq_bitmap = alloc_bootmem(size);
if (!mpic->hwirq_bitmap) {
pr_debug("mpic: ENOMEM allocating allocator bitmap!\n");
return -ENOMEM;
}
memset(mpic->hwirq_bitmap, 0, size);
rc = mpic_msi_reserve_dt_hwirqs(mpic);
if (rc) {
if (mpic->flags & MPIC_U3_HT_IRQS)
rc = mpic_msi_reserve_u3_hwirqs(mpic);
if (rc)
goto out_free;
}
return 0;
out_free:
if (mem_init_done)
kfree(mpic->hwirq_bitmap);
mpic->hwirq_bitmap = NULL;
return rc;
}
