/*
* This file manages the translation entries for the IBM Calgary IOMMU.
*
* Derived from arch/powerpc/platforms/pseries/iommu.c
*
* Copyright (C) IBM Corporation, 2006
*
* Author: Jon Mason <jdmason@us.ibm.com>
* Author: Muli Ben-Yehuda <muli@il.ibm.com>
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/bootmem.h>
#include <asm/tce.h>
#include <asm/calgary.h>
#include <asm/proto.h>
/* flush a tce at 'tceaddr' to main memory */
static inline void flush_tce(void* tceaddr)
{
/* a single tce can't cross a cache line */
if (cpu_has_clflush)
asm volatile("clflush (%0)" :: "r" (tceaddr));
else
asm volatile("wbinvd":::"memory");
}
void tce_build(struct iommu_table *tbl, unsigned long index,
unsigned int npages, unsigned long uaddr, int direction)
{
u64* tp;
u64 t;
u64 rpn;
t = (1 << TCE_READ_SHIFT);
if (direction != DMA_TO_DEVICE)
t |= (1 << TCE_WRITE_SHIFT);
tp = ((u64*)tbl->it_base) + index;
while (npages--) {
rpn = (virt_to_bus((void*)uaddr)) >> PAGE_SHIFT;
t &= ~TCE_RPN_MASK;
t |= (rpn << TCE_RPN_SHIFT);
*tp = cpu_to_be64(t);
flush_tce(tp);
uaddr += PAGE_SIZE;
tp++;
}
}
void tce_free(struct iommu_table *tbl, long index, unsigned int npages)
{
u64* tp;
tp = ((u64*)tbl->it_base) + index;
while (npages--) {
*tp = cpu_to_be64(0);
flush_tce(tp);
tp++;
}
}
static inline unsigned int table_size_to_number_of_entries(unsigned char size)
{
/*
* size is the order of the table, 0-7
* smallest table is 8K entries, so shift result by 13 to
* multiply by 8K
*/
return (1 << size) << 13;
}
static int tce_table_setparms(struct pci_dev *dev, struct iommu_table *tbl)
{
unsigned int bitmapsz;
unsigned long bmppages;
int ret;
tbl->it_busno = dev->bus->number;
/* set the tce table size - measured in entries */
tbl->it_size = table_size_to_number_of_entries(specified_table_size);
/*
* number of bytes needed for the bitmap size in number of
* entries; we need one bit per entry
*/
bitmapsz = tbl->it_size / BITS_PER_BYTE;
bmppages = __get_free_pages(GFP_KERNEL, get_order(bitmapsz));
if (!bmppages) {
printk(KERN_ERR "Calgary: cannot allocate bitmap\n");
ret = -ENOMEM;
goto done;
}
tbl->it_map = (unsigned long*)bmppages;
memset(tbl->it_map, 0, bitmapsz);
tbl->it_hint = 0;
spin_lock_init(&tbl->it_lock);
return 0;
done:
return ret;
}
int build_tce_table(struct pci_dev *dev, void __iomem *bbar)
{
struct iommu_table *tbl;
int ret;
if (dev->sysdata) {
printk(KERN_ERR "Calgary: dev %p has sysdata %p\n",
dev, dev->sysdata);
BUG();
}
tbl = kzalloc(sizeof(struct iommu_table), GFP_KERNEL);
if (!tbl) {
printk(KERN_ERR "Calgary: error allocating iommu_table\n");
ret = -ENOMEM;
goto done;
}
ret = tce_table_setparms(dev, tbl);
if (ret)
goto free_tbl;
tbl->bbar = bbar;
/*
* NUMA is already using the bus's sysdata pointer, so we use
* the bus's pci_dev's sysdata instead.
*/
dev->sysdata = tbl;
return 0;
free_tbl:
kfree(tbl);
done:
return ret;
}
void* alloc_tce_table(void)
{
unsigned int size;
size = table_size_to_number_of_entries(specified_table_size);
size *= TCE_ENTRY_SIZE;
return __alloc_bootmem_low(size, size, 0);
}
void free_tce_table(void *tbl)
{
unsigned int size;
if (!tbl)
return;
size = table_size_to_number_of_entries(specified_table_size);
size *= TCE_ENTRY_SIZE;
free_bootmem(__pa(tbl), size);
}
