linux/arch/x86/kernel/amd_iommu_init.c
Joerg Roedel 918ad6c54d x86, AMD IOMMU: add kernel command line parameters for AMD IOMMU
This patch adds two parameters to the kernel command line to control behavior
of the AMD IOMMU.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Cc: iommu@lists.linux-foundation.org
Cc: bhavna.sarathy@amd.com
Cc: Sebastian.Biemueller@amd.com
Cc: robert.richter@amd.com
Cc: joro@8bytes.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-27 10:12:14 +02:00

826 lines
19 KiB
C

/*
* Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
* Author: Joerg Roedel <joerg.roedel@amd.com>
* Leo Duran <leo.duran@amd.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*
* 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/pci.h>
#include <linux/acpi.h>
#include <linux/gfp.h>
#include <linux/list.h>
#include <asm/pci-direct.h>
#include <asm/amd_iommu_types.h>
#include <asm/gart.h>
/*
* definitions for the ACPI scanning code
*/
#define UPDATE_LAST_BDF(x) do {\
if ((x) > amd_iommu_last_bdf) \
amd_iommu_last_bdf = (x); \
} while (0);
#define DEVID(bus, devfn) (((bus) << 8) | (devfn))
#define PCI_BUS(x) (((x) >> 8) & 0xff)
#define IVRS_HEADER_LENGTH 48
#define TBL_SIZE(x) (1 << (PAGE_SHIFT + get_order(amd_iommu_last_bdf * (x))))
#define ACPI_IVHD_TYPE 0x10
#define ACPI_IVMD_TYPE_ALL 0x20
#define ACPI_IVMD_TYPE 0x21
#define ACPI_IVMD_TYPE_RANGE 0x22
#define IVHD_DEV_ALL 0x01
#define IVHD_DEV_SELECT 0x02
#define IVHD_DEV_SELECT_RANGE_START 0x03
#define IVHD_DEV_RANGE_END 0x04
#define IVHD_DEV_ALIAS 0x42
#define IVHD_DEV_ALIAS_RANGE 0x43
#define IVHD_DEV_EXT_SELECT 0x46
#define IVHD_DEV_EXT_SELECT_RANGE 0x47
#define IVHD_FLAG_HT_TUN_EN 0x00
#define IVHD_FLAG_PASSPW_EN 0x01
#define IVHD_FLAG_RESPASSPW_EN 0x02
#define IVHD_FLAG_ISOC_EN 0x03
#define IVMD_FLAG_EXCL_RANGE 0x08
#define IVMD_FLAG_UNITY_MAP 0x01
#define ACPI_DEVFLAG_INITPASS 0x01
#define ACPI_DEVFLAG_EXTINT 0x02
#define ACPI_DEVFLAG_NMI 0x04
#define ACPI_DEVFLAG_SYSMGT1 0x10
#define ACPI_DEVFLAG_SYSMGT2 0x20
#define ACPI_DEVFLAG_LINT0 0x40
#define ACPI_DEVFLAG_LINT1 0x80
#define ACPI_DEVFLAG_ATSDIS 0x10000000
struct ivhd_header {
u8 type;
u8 flags;
u16 length;
u16 devid;
u16 cap_ptr;
u64 mmio_phys;
u16 pci_seg;
u16 info;
u32 reserved;
} __attribute__((packed));
struct ivhd_entry {
u8 type;
u16 devid;
u8 flags;
u32 ext;
} __attribute__((packed));
struct ivmd_header {
u8 type;
u8 flags;
u16 length;
u16 devid;
u16 aux;
u64 resv;
u64 range_start;
u64 range_length;
} __attribute__((packed));
static int __initdata amd_iommu_disable;
u16 amd_iommu_last_bdf;
struct list_head amd_iommu_unity_map;
unsigned amd_iommu_aperture_order = 26;
int amd_iommu_isolate;
struct list_head amd_iommu_list;
struct dev_table_entry *amd_iommu_dev_table;
u16 *amd_iommu_alias_table;
struct amd_iommu **amd_iommu_rlookup_table;
struct protection_domain **amd_iommu_pd_table;
unsigned long *amd_iommu_pd_alloc_bitmap;
static u32 dev_table_size;
static u32 alias_table_size;
static u32 rlookup_table_size;
static void __init iommu_set_exclusion_range(struct amd_iommu *iommu)
{
u64 start = iommu->exclusion_start & PAGE_MASK;
u64 limit = (start + iommu->exclusion_length) & PAGE_MASK;
u64 entry;
if (!iommu->exclusion_start)
return;
entry = start | MMIO_EXCL_ENABLE_MASK;
memcpy_toio(iommu->mmio_base + MMIO_EXCL_BASE_OFFSET,
&entry, sizeof(entry));
entry = limit;
memcpy_toio(iommu->mmio_base + MMIO_EXCL_LIMIT_OFFSET,
&entry, sizeof(entry));
}
static void __init iommu_set_device_table(struct amd_iommu *iommu)
{
u32 entry;
BUG_ON(iommu->mmio_base == NULL);
entry = virt_to_phys(amd_iommu_dev_table);
entry |= (dev_table_size >> 12) - 1;
memcpy_toio(iommu->mmio_base + MMIO_DEV_TABLE_OFFSET,
&entry, sizeof(entry));
}
static void __init iommu_feature_enable(struct amd_iommu *iommu, u8 bit)
{
u32 ctrl;
ctrl = readl(iommu->mmio_base + MMIO_CONTROL_OFFSET);
ctrl |= (1 << bit);
writel(ctrl, iommu->mmio_base + MMIO_CONTROL_OFFSET);
}
static void __init iommu_feature_disable(struct amd_iommu *iommu, u8 bit)
{
u32 ctrl;
ctrl = (u64)readl(iommu->mmio_base + MMIO_CONTROL_OFFSET);
ctrl &= ~(1 << bit);
writel(ctrl, iommu->mmio_base + MMIO_CONTROL_OFFSET);
}
void __init iommu_enable(struct amd_iommu *iommu)
{
u32 ctrl;
printk(KERN_INFO "AMD IOMMU: Enabling IOMMU at ");
print_devid(iommu->devid, 0);
printk(" cap 0x%hx\n", iommu->cap_ptr);
iommu_feature_enable(iommu, CONTROL_IOMMU_EN);
ctrl = readl(iommu->mmio_base + MMIO_CONTROL_OFFSET);
}
static u8 * __init iommu_map_mmio_space(u64 address)
{
u8 *ret;
if (!request_mem_region(address, MMIO_REGION_LENGTH, "amd_iommu"))
return NULL;
ret = ioremap_nocache(address, MMIO_REGION_LENGTH);
if (ret != NULL)
return ret;
release_mem_region(address, MMIO_REGION_LENGTH);
return NULL;
}
static void __init iommu_unmap_mmio_space(struct amd_iommu *iommu)
{
if (iommu->mmio_base)
iounmap(iommu->mmio_base);
release_mem_region(iommu->mmio_phys, MMIO_REGION_LENGTH);
}
static int __init find_last_devid_on_pci(int bus, int dev, int fn, int cap_ptr)
{
u32 cap;
cap = read_pci_config(bus, dev, fn, cap_ptr+MMIO_RANGE_OFFSET);
UPDATE_LAST_BDF(DEVID(MMIO_GET_BUS(cap), MMIO_GET_LD(cap)));
return 0;
}
static int __init find_last_devid_from_ivhd(struct ivhd_header *h)
{
u8 *p = (void *)h, *end = (void *)h;
struct ivhd_entry *dev;
p += sizeof(*h);
end += h->length;
find_last_devid_on_pci(PCI_BUS(h->devid),
PCI_SLOT(h->devid),
PCI_FUNC(h->devid),
h->cap_ptr);
while (p < end) {
dev = (struct ivhd_entry *)p;
switch (dev->type) {
case IVHD_DEV_SELECT:
case IVHD_DEV_RANGE_END:
case IVHD_DEV_ALIAS:
case IVHD_DEV_EXT_SELECT:
UPDATE_LAST_BDF(dev->devid);
break;
default:
break;
}
p += 0x04 << (*p >> 6);
}
WARN_ON(p != end);
return 0;
}
static int __init find_last_devid_acpi(struct acpi_table_header *table)
{
int i;
u8 checksum = 0, *p = (u8 *)table, *end = (u8 *)table;
struct ivhd_header *h;
/*
* Validate checksum here so we don't need to do it when
* we actually parse the table
*/
for (i = 0; i < table->length; ++i)
checksum += p[i];
if (checksum != 0)
/* ACPI table corrupt */
return -ENODEV;
p += IVRS_HEADER_LENGTH;
end += table->length;
while (p < end) {
h = (struct ivhd_header *)p;
switch (h->type) {
case ACPI_IVHD_TYPE:
find_last_devid_from_ivhd(h);
break;
default:
break;
}
p += h->length;
}
WARN_ON(p != end);
return 0;
}
static u8 * __init alloc_command_buffer(struct amd_iommu *iommu)
{
u8 *cmd_buf = (u8 *)__get_free_pages(GFP_KERNEL,
get_order(CMD_BUFFER_SIZE));
u64 entry = 0;
if (cmd_buf == NULL)
return NULL;
iommu->cmd_buf_size = CMD_BUFFER_SIZE;
memset(cmd_buf, 0, CMD_BUFFER_SIZE);
entry = (u64)virt_to_phys(cmd_buf);
entry |= MMIO_CMD_SIZE_512;
memcpy_toio(iommu->mmio_base + MMIO_CMD_BUF_OFFSET,
&entry, sizeof(entry));
iommu_feature_enable(iommu, CONTROL_CMDBUF_EN);
return cmd_buf;
}
static void __init free_command_buffer(struct amd_iommu *iommu)
{
if (iommu->cmd_buf)
free_pages((unsigned long)iommu->cmd_buf,
get_order(CMD_BUFFER_SIZE));
}
static void set_dev_entry_bit(u16 devid, u8 bit)
{
int i = (bit >> 5) & 0x07;
int _bit = bit & 0x1f;
amd_iommu_dev_table[devid].data[i] |= (1 << _bit);
}
static void __init set_dev_entry_from_acpi(u16 devid, u32 flags, u32 ext_flags)
{
if (flags & ACPI_DEVFLAG_INITPASS)
set_dev_entry_bit(devid, DEV_ENTRY_INIT_PASS);
if (flags & ACPI_DEVFLAG_EXTINT)
set_dev_entry_bit(devid, DEV_ENTRY_EINT_PASS);
if (flags & ACPI_DEVFLAG_NMI)
set_dev_entry_bit(devid, DEV_ENTRY_NMI_PASS);
if (flags & ACPI_DEVFLAG_SYSMGT1)
set_dev_entry_bit(devid, DEV_ENTRY_SYSMGT1);
if (flags & ACPI_DEVFLAG_SYSMGT2)
set_dev_entry_bit(devid, DEV_ENTRY_SYSMGT2);
if (flags & ACPI_DEVFLAG_LINT0)
set_dev_entry_bit(devid, DEV_ENTRY_LINT0_PASS);
if (flags & ACPI_DEVFLAG_LINT1)
set_dev_entry_bit(devid, DEV_ENTRY_LINT1_PASS);
}
static void __init set_iommu_for_device(struct amd_iommu *iommu, u16 devid)
{
amd_iommu_rlookup_table[devid] = iommu;
}
static void __init set_device_exclusion_range(u16 devid, struct ivmd_header *m)
{
struct amd_iommu *iommu = amd_iommu_rlookup_table[devid];
if (!(m->flags & IVMD_FLAG_EXCL_RANGE))
return;
if (iommu) {
set_dev_entry_bit(m->devid, DEV_ENTRY_EX);
iommu->exclusion_start = m->range_start;
iommu->exclusion_length = m->range_length;
}
}
static void __init init_iommu_from_pci(struct amd_iommu *iommu)
{
int bus = PCI_BUS(iommu->devid);
int dev = PCI_SLOT(iommu->devid);
int fn = PCI_FUNC(iommu->devid);
int cap_ptr = iommu->cap_ptr;
u32 range;
iommu->cap = read_pci_config(bus, dev, fn, cap_ptr+MMIO_CAP_HDR_OFFSET);
range = read_pci_config(bus, dev, fn, cap_ptr+MMIO_RANGE_OFFSET);
iommu->first_device = DEVID(MMIO_GET_BUS(range), MMIO_GET_FD(range));
iommu->last_device = DEVID(MMIO_GET_BUS(range), MMIO_GET_LD(range));
}
static void __init init_iommu_from_acpi(struct amd_iommu *iommu,
struct ivhd_header *h)
{
u8 *p = (u8 *)h;
u8 *end = p, flags = 0;
u16 dev_i, devid = 0, devid_start = 0, devid_to = 0;
u32 ext_flags = 0;
bool alias = 0;
struct ivhd_entry *e;
/*
* First set the recommended feature enable bits from ACPI
* into the IOMMU control registers
*/
h->flags & IVHD_FLAG_HT_TUN_EN ?
iommu_feature_enable(iommu, CONTROL_HT_TUN_EN) :
iommu_feature_disable(iommu, CONTROL_HT_TUN_EN);
h->flags & IVHD_FLAG_PASSPW_EN ?
iommu_feature_enable(iommu, CONTROL_PASSPW_EN) :
iommu_feature_disable(iommu, CONTROL_PASSPW_EN);
h->flags & IVHD_FLAG_RESPASSPW_EN ?
iommu_feature_enable(iommu, CONTROL_RESPASSPW_EN) :
iommu_feature_disable(iommu, CONTROL_RESPASSPW_EN);
h->flags & IVHD_FLAG_ISOC_EN ?
iommu_feature_enable(iommu, CONTROL_ISOC_EN) :
iommu_feature_disable(iommu, CONTROL_ISOC_EN);
/*
* make IOMMU memory accesses cache coherent
*/
iommu_feature_enable(iommu, CONTROL_COHERENT_EN);
/*
* Done. Now parse the device entries
*/
p += sizeof(struct ivhd_header);
end += h->length;
while (p < end) {
e = (struct ivhd_entry *)p;
switch (e->type) {
case IVHD_DEV_ALL:
for (dev_i = iommu->first_device;
dev_i <= iommu->last_device; ++dev_i)
set_dev_entry_from_acpi(dev_i, e->flags, 0);
break;
case IVHD_DEV_SELECT:
devid = e->devid;
set_dev_entry_from_acpi(devid, e->flags, 0);
break;
case IVHD_DEV_SELECT_RANGE_START:
devid_start = e->devid;
flags = e->flags;
ext_flags = 0;
alias = 0;
break;
case IVHD_DEV_ALIAS:
devid = e->devid;
devid_to = e->ext >> 8;
set_dev_entry_from_acpi(devid, e->flags, 0);
amd_iommu_alias_table[devid] = devid_to;
break;
case IVHD_DEV_ALIAS_RANGE:
devid_start = e->devid;
flags = e->flags;
devid_to = e->ext >> 8;
ext_flags = 0;
alias = 1;
break;
case IVHD_DEV_EXT_SELECT:
devid = e->devid;
set_dev_entry_from_acpi(devid, e->flags, e->ext);
break;
case IVHD_DEV_EXT_SELECT_RANGE:
devid_start = e->devid;
flags = e->flags;
ext_flags = e->ext;
alias = 0;
break;
case IVHD_DEV_RANGE_END:
devid = e->devid;
for (dev_i = devid_start; dev_i <= devid; ++dev_i) {
if (alias)
amd_iommu_alias_table[dev_i] = devid_to;
set_dev_entry_from_acpi(
amd_iommu_alias_table[dev_i],
flags, ext_flags);
}
break;
default:
break;
}
p += 0x04 << (e->type >> 6);
}
}
static int __init init_iommu_devices(struct amd_iommu *iommu)
{
u16 i;
for (i = iommu->first_device; i <= iommu->last_device; ++i)
set_iommu_for_device(iommu, i);
return 0;
}
static void __init free_iommu_one(struct amd_iommu *iommu)
{
free_command_buffer(iommu);
iommu_unmap_mmio_space(iommu);
}
static void __init free_iommu_all(void)
{
struct amd_iommu *iommu, *next;
list_for_each_entry_safe(iommu, next, &amd_iommu_list, list) {
list_del(&iommu->list);
free_iommu_one(iommu);
kfree(iommu);
}
}
static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h)
{
spin_lock_init(&iommu->lock);
list_add_tail(&iommu->list, &amd_iommu_list);
/*
* Copy data from ACPI table entry to the iommu struct
*/
iommu->devid = h->devid;
iommu->cap_ptr = h->cap_ptr;
iommu->mmio_phys = h->mmio_phys;
iommu->mmio_base = iommu_map_mmio_space(h->mmio_phys);
if (!iommu->mmio_base)
return -ENOMEM;
iommu_set_device_table(iommu);
iommu->cmd_buf = alloc_command_buffer(iommu);
if (!iommu->cmd_buf)
return -ENOMEM;
init_iommu_from_pci(iommu);
init_iommu_from_acpi(iommu, h);
init_iommu_devices(iommu);
return 0;
}
static int __init init_iommu_all(struct acpi_table_header *table)
{
u8 *p = (u8 *)table, *end = (u8 *)table;
struct ivhd_header *h;
struct amd_iommu *iommu;
int ret;
INIT_LIST_HEAD(&amd_iommu_list);
end += table->length;
p += IVRS_HEADER_LENGTH;
while (p < end) {
h = (struct ivhd_header *)p;
switch (*p) {
case ACPI_IVHD_TYPE:
iommu = kzalloc(sizeof(struct amd_iommu), GFP_KERNEL);
if (iommu == NULL)
return -ENOMEM;
ret = init_iommu_one(iommu, h);
if (ret)
return ret;
break;
default:
break;
}
p += h->length;
}
WARN_ON(p != end);
return 0;
}
static void __init free_unity_maps(void)
{
struct unity_map_entry *entry, *next;
list_for_each_entry_safe(entry, next, &amd_iommu_unity_map, list) {
list_del(&entry->list);
kfree(entry);
}
}
static int __init init_exclusion_range(struct ivmd_header *m)
{
int i;
switch (m->type) {
case ACPI_IVMD_TYPE:
set_device_exclusion_range(m->devid, m);
break;
case ACPI_IVMD_TYPE_ALL:
for (i = 0; i < amd_iommu_last_bdf; ++i)
set_device_exclusion_range(i, m);
break;
case ACPI_IVMD_TYPE_RANGE:
for (i = m->devid; i <= m->aux; ++i)
set_device_exclusion_range(i, m);
break;
default:
break;
}
return 0;
}
static int __init init_unity_map_range(struct ivmd_header *m)
{
struct unity_map_entry *e = 0;
e = kzalloc(sizeof(*e), GFP_KERNEL);
if (e == NULL)
return -ENOMEM;
switch (m->type) {
default:
case ACPI_IVMD_TYPE:
e->devid_start = e->devid_end = m->devid;
break;
case ACPI_IVMD_TYPE_ALL:
e->devid_start = 0;
e->devid_end = amd_iommu_last_bdf;
break;
case ACPI_IVMD_TYPE_RANGE:
e->devid_start = m->devid;
e->devid_end = m->aux;
break;
}
e->address_start = PAGE_ALIGN(m->range_start);
e->address_end = e->address_start + PAGE_ALIGN(m->range_length);
e->prot = m->flags >> 1;
list_add_tail(&e->list, &amd_iommu_unity_map);
return 0;
}
static int __init init_memory_definitions(struct acpi_table_header *table)
{
u8 *p = (u8 *)table, *end = (u8 *)table;
struct ivmd_header *m;
INIT_LIST_HEAD(&amd_iommu_unity_map);
end += table->length;
p += IVRS_HEADER_LENGTH;
while (p < end) {
m = (struct ivmd_header *)p;
if (m->flags & IVMD_FLAG_EXCL_RANGE)
init_exclusion_range(m);
else if (m->flags & IVMD_FLAG_UNITY_MAP)
init_unity_map_range(m);
p += m->length;
}
return 0;
}
int __init amd_iommu_init(void)
{
int i, ret = 0;
if (amd_iommu_disable) {
printk(KERN_INFO "AMD IOMMU disabled by kernel command line\n");
return 0;
}
/*
* First parse ACPI tables to find the largest Bus/Dev/Func
* we need to handle. Upon this information the shared data
* structures for the IOMMUs in the system will be allocated
*/
if (acpi_table_parse("IVRS", find_last_devid_acpi) != 0)
return -ENODEV;
dev_table_size = TBL_SIZE(DEV_TABLE_ENTRY_SIZE);
alias_table_size = TBL_SIZE(ALIAS_TABLE_ENTRY_SIZE);
rlookup_table_size = TBL_SIZE(RLOOKUP_TABLE_ENTRY_SIZE);
ret = -ENOMEM;
/* Device table - directly used by all IOMMUs */
amd_iommu_dev_table = (void *)__get_free_pages(GFP_KERNEL,
get_order(dev_table_size));
if (amd_iommu_dev_table == NULL)
goto out;
/*
* Alias table - map PCI Bus/Dev/Func to Bus/Dev/Func the
* IOMMU see for that device
*/
amd_iommu_alias_table = (void *)__get_free_pages(GFP_KERNEL,
get_order(alias_table_size));
if (amd_iommu_alias_table == NULL)
goto free;
/* IOMMU rlookup table - find the IOMMU for a specific device */
amd_iommu_rlookup_table = (void *)__get_free_pages(GFP_KERNEL,
get_order(rlookup_table_size));
if (amd_iommu_rlookup_table == NULL)
goto free;
/*
* Protection Domain table - maps devices to protection domains
* This table has the same size as the rlookup_table
*/
amd_iommu_pd_table = (void *)__get_free_pages(GFP_KERNEL,
get_order(rlookup_table_size));
if (amd_iommu_pd_table == NULL)
goto free;
amd_iommu_pd_alloc_bitmap = (void *)__get_free_pages(GFP_KERNEL,
get_order(MAX_DOMAIN_ID/8));
if (amd_iommu_pd_alloc_bitmap == NULL)
goto free;
/*
* memory is allocated now; initialize the device table with all zeroes
* and let all alias entries point to itself
*/
memset(amd_iommu_dev_table, 0, dev_table_size);
for (i = 0; i < amd_iommu_last_bdf; ++i)
amd_iommu_alias_table[i] = i;
memset(amd_iommu_pd_table, 0, rlookup_table_size);
memset(amd_iommu_pd_alloc_bitmap, 0, MAX_DOMAIN_ID / 8);
/*
* never allocate domain 0 because its used as the non-allocated and
* error value placeholder
*/
amd_iommu_pd_alloc_bitmap[0] = 1;
/*
* now the data structures are allocated and basically initialized
* start the real acpi table scan
*/
ret = -ENODEV;
if (acpi_table_parse("IVRS", init_iommu_all) != 0)
goto free;
if (acpi_table_parse("IVRS", init_memory_definitions) != 0)
goto free;
printk(KERN_INFO "AMD IOMMU: aperture size is %d MB\n",
(1 << (amd_iommu_aperture_order-20)));
printk(KERN_INFO "AMD IOMMU: device isolation ");
if (amd_iommu_isolate)
printk("enabled\n");
else
printk("disabled\n");
out:
return ret;
free:
if (amd_iommu_pd_alloc_bitmap)
free_pages((unsigned long)amd_iommu_pd_alloc_bitmap, 1);
if (amd_iommu_pd_table)
free_pages((unsigned long)amd_iommu_pd_table,
get_order(rlookup_table_size));
if (amd_iommu_rlookup_table)
free_pages((unsigned long)amd_iommu_rlookup_table,
get_order(rlookup_table_size));
if (amd_iommu_alias_table)
free_pages((unsigned long)amd_iommu_alias_table,
get_order(alias_table_size));
if (amd_iommu_dev_table)
free_pages((unsigned long)amd_iommu_dev_table,
get_order(dev_table_size));
free_iommu_all();
free_unity_maps();
goto out;
}
static int __init early_amd_iommu_detect(struct acpi_table_header *table)
{
return 0;
}
void __init amd_iommu_detect(void)
{
if (swiotlb || no_iommu || iommu_detected)
return;
if (amd_iommu_disable)
return;
if (acpi_table_parse("IVRS", early_amd_iommu_detect) == 0) {
iommu_detected = 1;
gart_iommu_aperture_disabled = 1;
gart_iommu_aperture = 0;
}
}
static int __init parse_amd_iommu_options(char *str)
{
for (; *str; ++str) {
if (strcmp(str, "off") == 0)
amd_iommu_disable = 1;
if (strcmp(str, "isolate") == 0)
amd_iommu_isolate = 1;
}
return 1;
}
static int __init parse_amd_iommu_size_options(char *str)
{
for (; *str; ++str) {
if (strcmp(str, "32M") == 0)
amd_iommu_aperture_order = 25;
if (strcmp(str, "64M") == 0)
amd_iommu_aperture_order = 26;
if (strcmp(str, "128M") == 0)
amd_iommu_aperture_order = 27;
if (strcmp(str, "256M") == 0)
amd_iommu_aperture_order = 28;
if (strcmp(str, "512M") == 0)
amd_iommu_aperture_order = 29;
if (strcmp(str, "1G") == 0)
amd_iommu_aperture_order = 30;
}
return 1;
}
__setup("amd_iommu=", parse_amd_iommu_options);
__setup("amd_iommu_size=", parse_amd_iommu_size_options);