/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2001-2006 Silicon Graphics, Inc. All rights reserved.
*/
#include <linux/types.h>
#include <asm/sn/sn_sal.h>
#include <asm/sn/pcibr_provider.h>
#include <asm/sn/pcibus_provider_defs.h>
#include <asm/sn/pcidev.h>
int pcibr_invalidate_ate; /* by default don't invalidate ATE on free */
/*
* mark_ate: Mark the ate as either free or inuse.
*/
static void mark_ate(struct ate_resource *ate_resource, int start, int number,
u64 value)
{
u64 *ate = ate_resource->ate;
int index;
int length = 0;
for (index = start; length < number; index++, length++)
ate[index] = value;
}
/*
* find_free_ate: Find the first free ate index starting from the given
* index for the desired consequtive count.
*/
static int find_free_ate(struct ate_resource *ate_resource, int start,
int count)
{
u64 *ate = ate_resource->ate;
int index;
int start_free;
for (index = start; index < ate_resource->num_ate;) {
if (!ate[index]) {
int i;
int free;
free = 0;
start_free = index; /* Found start free ate */
for (i = start_free; i < ate_resource->num_ate; i++) {
if (!ate[i]) { /* This is free */
if (++free == count)
return start_free;
} else {
index = i + 1;
break;
}
}
} else
index++; /* Try next ate */
}
return -1;
}
/*
* free_ate_resource: Free the requested number of ATEs.
*/
static inline void free_ate_resource(struct ate_resource *ate_resource,
int start)
{
mark_ate(ate_resource, start, ate_resource->ate[start], 0);
if ((ate_resource->lowest_free_index > start) ||
(ate_resource->lowest_free_index < 0))
ate_resource->lowest_free_index = start;
}
/*
* alloc_ate_resource: Allocate the requested number of ATEs.
*/
static inline int alloc_ate_resource(struct ate_resource *ate_resource,
int ate_needed)
{
int start_index;
/*
* Check for ate exhaustion.
*/
if (ate_resource->lowest_free_index < 0)
return -1;
/*
* Find the required number of free consequtive ates.
*/
start_index =
find_free_ate(ate_resource, ate_resource->lowest_free_index,
ate_needed);
if (start_index >= 0)
mark_ate(ate_resource, start_index, ate_needed, ate_needed);
ate_resource->lowest_free_index =
find_free_ate(ate_resource, ate_resource->lowest_free_index, 1);
return start_index;
}
/*
* Allocate "count" contiguous Bridge Address Translation Entries
* on the specified bridge to be used for PCI to XTALK mappings.
* Indices in rm map range from 1..num_entries. Indicies returned
* to caller range from 0..num_entries-1.
*
* Return the start index on success, -1 on failure.
*/
int pcibr_ate_alloc(struct pcibus_info *pcibus_info, int count)
{
int status;
unsigned long flags;
spin_lock_irqsave(&pcibus_info->pbi_lock, flags);
status = alloc_ate_resource(&pcibus_info->pbi_int_ate_resource, count);
spin_unlock_irqrestore(&pcibus_info->pbi_lock, flags);
return status;
}
/*
* Setup an Address Translation Entry as specified. Use either the Bridge
* internal maps or the external map RAM, as appropriate.
*/
static inline u64 *pcibr_ate_addr(struct pcibus_info *pcibus_info,
int ate_index)
{
if (ate_index < pcibus_info->pbi_int_ate_size) {
return pcireg_int_ate_addr(pcibus_info, ate_index);
}
panic("pcibr_ate_addr: invalid ate_index 0x%x", ate_index);
}
/*
* Update the ate.
*/
void inline
ate_write(struct pcibus_info *pcibus_info, int ate_index, int count,
volatile u64 ate)
{
while (count-- > 0) {
if (ate_index < pcibus_info->pbi_int_ate_size) {
pcireg_int_ate_set(pcibus_info, ate_index, ate);
} else {
panic("ate_write: invalid ate_index 0x%x", ate_index);
}
ate_index++;
ate += IOPGSIZE;
}
pcireg_tflush_get(pcibus_info); /* wait until Bridge PIO complete */
}
void pcibr_ate_free(struct pcibus_info *pcibus_info, int index)
{
volatile u64 ate;
int count;
u64 flags;
if (pcibr_invalidate_ate) {
/* For debugging purposes, clear the valid bit in the ATE */
ate = *pcibr_ate_addr(pcibus_info, index);
count = pcibus_info->pbi_int_ate_resource.ate[index];
ate_write(pcibus_info, index, count, (ate & ~PCI32_ATE_V));
}
spin_lock_irqsave(&pcibus_info->pbi_lock, flags);
free_ate_resource(&pcibus_info->pbi_int_ate_resource, index);
spin_unlock_irqrestore(&pcibus_info->pbi_lock, flags);
}
