370 lines
10 KiB
C
Executable File
370 lines
10 KiB
C
Executable File
/*
|
|
* OF helpers for IOMMU
|
|
*
|
|
* Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms and conditions of the GNU General Public License,
|
|
* version 2, as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope 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.,
|
|
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
|
|
*/
|
|
|
|
#include <linux/export.h>
|
|
#include <linux/iommu.h>
|
|
#include <linux/limits.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_iommu.h>
|
|
#include <linux/of_pci.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/fsl/mc.h>
|
|
|
|
#define NO_IOMMU 1
|
|
|
|
static const struct of_device_id __iommu_of_table_sentinel
|
|
__used __section(__iommu_of_table_end);
|
|
|
|
/**
|
|
* of_get_dma_window - Parse *dma-window property and returns 0 if found.
|
|
*
|
|
* @dn: device node
|
|
* @prefix: prefix for property name if any
|
|
* @index: index to start to parse
|
|
* @busno: Returns busno if supported. Otherwise pass NULL
|
|
* @addr: Returns address that DMA starts
|
|
* @size: Returns the range that DMA can handle
|
|
*
|
|
* This supports different formats flexibly. "prefix" can be
|
|
* configured if any. "busno" and "index" are optionally
|
|
* specified. Set 0(or NULL) if not used.
|
|
*/
|
|
int of_get_dma_window(struct device_node *dn, const char *prefix, int index,
|
|
unsigned long *busno, dma_addr_t *addr, size_t *size)
|
|
{
|
|
const __be32 *dma_window, *end;
|
|
int bytes, cur_index = 0;
|
|
char propname[NAME_MAX], addrname[NAME_MAX], sizename[NAME_MAX];
|
|
|
|
if (!dn || !addr || !size)
|
|
return -EINVAL;
|
|
|
|
if (!prefix)
|
|
prefix = "";
|
|
|
|
snprintf(propname, sizeof(propname), "%sdma-window", prefix);
|
|
snprintf(addrname, sizeof(addrname), "%s#dma-address-cells", prefix);
|
|
snprintf(sizename, sizeof(sizename), "%s#dma-size-cells", prefix);
|
|
|
|
dma_window = of_get_property(dn, propname, &bytes);
|
|
if (!dma_window)
|
|
return -ENODEV;
|
|
end = dma_window + bytes / sizeof(*dma_window);
|
|
|
|
while (dma_window < end) {
|
|
u32 cells;
|
|
const void *prop;
|
|
|
|
/* busno is one cell if supported */
|
|
if (busno)
|
|
*busno = be32_to_cpup(dma_window++);
|
|
|
|
prop = of_get_property(dn, addrname, NULL);
|
|
if (!prop)
|
|
prop = of_get_property(dn, "#address-cells", NULL);
|
|
|
|
cells = prop ? be32_to_cpup(prop) : of_n_addr_cells(dn);
|
|
if (!cells)
|
|
return -EINVAL;
|
|
*addr = of_read_number(dma_window, cells);
|
|
dma_window += cells;
|
|
|
|
prop = of_get_property(dn, sizename, NULL);
|
|
cells = prop ? be32_to_cpup(prop) : of_n_size_cells(dn);
|
|
if (!cells)
|
|
return -EINVAL;
|
|
*size = of_read_number(dma_window, cells);
|
|
dma_window += cells;
|
|
|
|
if (cur_index++ == index)
|
|
break;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(of_get_dma_window);
|
|
|
|
static bool of_iommu_driver_present(struct device_node *np)
|
|
{
|
|
/*
|
|
* If the IOMMU still isn't ready by the time we reach init, assume
|
|
* it never will be. We don't want to defer indefinitely, nor attempt
|
|
* to dereference __iommu_of_table after it's been freed.
|
|
*/
|
|
if (system_state >= SYSTEM_RUNNING)
|
|
return false;
|
|
|
|
return of_match_node(&__iommu_of_table, np);
|
|
}
|
|
|
|
static int of_iommu_xlate(struct device *dev,
|
|
struct of_phandle_args *iommu_spec)
|
|
{
|
|
const struct iommu_ops *ops;
|
|
struct fwnode_handle *fwnode = &iommu_spec->np->fwnode;
|
|
int err;
|
|
|
|
ops = iommu_ops_from_fwnode(fwnode);
|
|
if ((ops && !ops->of_xlate) ||
|
|
!of_device_is_available(iommu_spec->np) ||
|
|
(!ops && !of_iommu_driver_present(iommu_spec->np)))
|
|
return NO_IOMMU;
|
|
|
|
err = iommu_fwspec_init(dev, &iommu_spec->np->fwnode, ops);
|
|
if (err)
|
|
return err;
|
|
/*
|
|
* The otherwise-empty fwspec handily serves to indicate the specific
|
|
* IOMMU device we're waiting for, which will be useful if we ever get
|
|
* a proper probe-ordering dependency mechanism in future.
|
|
*/
|
|
if (!ops)
|
|
return -EPROBE_DEFER;
|
|
|
|
return ops->of_xlate(dev, iommu_spec);
|
|
}
|
|
|
|
struct of_pci_iommu_alias_info {
|
|
struct device *dev;
|
|
struct device_node *np;
|
|
};
|
|
|
|
/**
|
|
* of_map_rid - Translate a requester ID through a downstream mapping.
|
|
* @np: root complex device node.
|
|
* @rid: Requester ID to map.
|
|
* @map_name: property name of the map to use.
|
|
* @map_mask_name: optional property name of the mask to use.
|
|
* @target: optional pointer to a target device node.
|
|
* @id_out: optional pointer to receive the translated ID.
|
|
*
|
|
* Given PCI/MC requester ID, look up the appropriate implementation-defined
|
|
* platform ID and/or the target device which receives transactions on that
|
|
* ID, as per the "iommu-map" and "msi-map" bindings. Either of @target or
|
|
* @id_out may be NULL if only the other is required. If @target points to
|
|
* a non-NULL device node pointer, only entries targeting that node will be
|
|
* matched; if it points to a NULL value, it will receive the device node of
|
|
* the first matching target phandle, with a reference held.
|
|
*
|
|
* Return: 0 on success or a standard error code on failure.
|
|
*/
|
|
int of_map_rid(struct device_node *np, u32 rid,
|
|
const char *map_name, const char *map_mask_name,
|
|
struct device_node **target, u32 *id_out)
|
|
{
|
|
u32 map_mask, masked_rid;
|
|
int map_len;
|
|
const __be32 *map = NULL;
|
|
|
|
if (!np || !map_name || (!target && !id_out))
|
|
return -EINVAL;
|
|
|
|
map = of_get_property(np, map_name, &map_len);
|
|
if (!map) {
|
|
if (target)
|
|
return -ENODEV;
|
|
/* Otherwise, no map implies no translation */
|
|
*id_out = rid;
|
|
return 0;
|
|
}
|
|
|
|
if (!map_len || map_len % (4 * sizeof(*map))) {
|
|
pr_err("%pOF: Error: Bad %s length: %d\n", np,
|
|
map_name, map_len);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* The default is to select all bits. */
|
|
map_mask = 0xffffffff;
|
|
|
|
/*
|
|
* Can be overridden by "{iommu,msi}-map-mask" property.
|
|
* If of_property_read_u32() fails, the default is used.
|
|
*/
|
|
if (map_mask_name)
|
|
of_property_read_u32(np, map_mask_name, &map_mask);
|
|
|
|
masked_rid = map_mask & rid;
|
|
for ( ; map_len > 0; map_len -= 4 * sizeof(*map), map += 4) {
|
|
struct device_node *phandle_node;
|
|
u32 rid_base = be32_to_cpup(map + 0);
|
|
u32 phandle = be32_to_cpup(map + 1);
|
|
u32 out_base = be32_to_cpup(map + 2);
|
|
u32 rid_len = be32_to_cpup(map + 3);
|
|
|
|
if (rid_base & ~map_mask) {
|
|
pr_err("%pOF: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
|
|
np, map_name, map_name,
|
|
map_mask, rid_base);
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (masked_rid < rid_base || masked_rid >= rid_base + rid_len)
|
|
continue;
|
|
|
|
phandle_node = of_find_node_by_phandle(phandle);
|
|
if (!phandle_node)
|
|
return -ENODEV;
|
|
|
|
if (target) {
|
|
if (*target)
|
|
of_node_put(phandle_node);
|
|
else
|
|
*target = phandle_node;
|
|
|
|
if (*target != phandle_node)
|
|
continue;
|
|
}
|
|
|
|
if (id_out)
|
|
*id_out = masked_rid - rid_base + out_base;
|
|
|
|
pr_debug("%pOF: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
|
|
np, map_name, map_mask, rid_base, out_base,
|
|
rid_len, rid, *id_out);
|
|
return 0;
|
|
}
|
|
|
|
pr_err("%pOF: Invalid %s translation - no match for rid 0x%x on %pOF\n",
|
|
np, map_name, rid, target && *target ? *target : NULL);
|
|
return -EFAULT;
|
|
}
|
|
static int of_pci_iommu_init(struct pci_dev *pdev, u16 alias, void *data)
|
|
{
|
|
struct of_pci_iommu_alias_info *info = data;
|
|
struct of_phandle_args iommu_spec = { .args_count = 1 };
|
|
int err;
|
|
|
|
err = of_map_rid(info->np, alias, "iommu-map",
|
|
"iommu-map-mask", &iommu_spec.np,
|
|
iommu_spec.args);
|
|
if (err)
|
|
return err == -ENODEV ? NO_IOMMU : err;
|
|
|
|
err = of_iommu_xlate(info->dev, &iommu_spec);
|
|
of_node_put(iommu_spec.np);
|
|
return err;
|
|
}
|
|
|
|
static int of_fsl_mc_iommu_init(struct fsl_mc_device *mc_dev,
|
|
struct device_node *master_np)
|
|
{
|
|
struct of_phandle_args iommu_spec = { .args_count = 1 };
|
|
int err;
|
|
|
|
err = of_map_rid(master_np, mc_dev->icid, "iommu-map",
|
|
"iommu-map-mask", &iommu_spec.np,
|
|
iommu_spec.args);
|
|
if (err)
|
|
return err == -ENODEV ? NO_IOMMU : err;
|
|
|
|
err = of_iommu_xlate(&mc_dev->dev, &iommu_spec);
|
|
of_node_put(iommu_spec.np);
|
|
return err;
|
|
}
|
|
|
|
const struct iommu_ops *of_iommu_configure(struct device *dev,
|
|
struct device_node *master_np)
|
|
{
|
|
const struct iommu_ops *ops = NULL;
|
|
struct iommu_fwspec *fwspec = dev->iommu_fwspec;
|
|
int err = NO_IOMMU;
|
|
|
|
if (!master_np)
|
|
return NULL;
|
|
|
|
if (fwspec) {
|
|
if (fwspec->ops)
|
|
return fwspec->ops;
|
|
|
|
/* In the deferred case, start again from scratch */
|
|
iommu_fwspec_free(dev);
|
|
}
|
|
|
|
/*
|
|
* We don't currently walk up the tree looking for a parent IOMMU.
|
|
* See the `Notes:' section of
|
|
* Documentation/devicetree/bindings/iommu/iommu.txt
|
|
*/
|
|
if (dev_is_pci(dev)) {
|
|
struct of_pci_iommu_alias_info info = {
|
|
.dev = dev,
|
|
.np = master_np,
|
|
};
|
|
|
|
err = pci_for_each_dma_alias(to_pci_dev(dev),
|
|
of_pci_iommu_init, &info);
|
|
} else if (dev_is_fsl_mc(dev)) {
|
|
err = of_fsl_mc_iommu_init(to_fsl_mc_device(dev), master_np);
|
|
} else {
|
|
struct of_phandle_args iommu_spec;
|
|
int idx = 0;
|
|
|
|
while (!of_parse_phandle_with_args(master_np, "iommus",
|
|
"#iommu-cells",
|
|
idx, &iommu_spec)) {
|
|
err = of_iommu_xlate(dev, &iommu_spec);
|
|
of_node_put(iommu_spec.np);
|
|
idx++;
|
|
if (err)
|
|
break;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Two success conditions can be represented by non-negative err here:
|
|
* >0 : there is no IOMMU, or one was unavailable for non-fatal reasons
|
|
* 0 : we found an IOMMU, and dev->fwspec is initialised appropriately
|
|
* <0 : any actual error
|
|
*/
|
|
if (!err)
|
|
ops = dev->iommu_fwspec->ops;
|
|
/*
|
|
* If we have reason to believe the IOMMU driver missed the initial
|
|
* add_device callback for dev, replay it to get things in order.
|
|
*/
|
|
if (ops && ops->add_device && dev->bus && !dev->iommu_group)
|
|
err = ops->add_device(dev);
|
|
|
|
/* Ignore all other errors apart from EPROBE_DEFER */
|
|
if (err == -EPROBE_DEFER) {
|
|
ops = ERR_PTR(err);
|
|
} else if (err < 0) {
|
|
dev_dbg(dev, "Adding to IOMMU failed: %d\n", err);
|
|
ops = NULL;
|
|
}
|
|
|
|
return ops;
|
|
}
|
|
|
|
static int __init of_iommu_init(void)
|
|
{
|
|
struct device_node *np;
|
|
const struct of_device_id *match, *matches = &__iommu_of_table;
|
|
|
|
for_each_matching_node_and_match(np, matches, &match) {
|
|
const of_iommu_init_fn init_fn = match->data;
|
|
|
|
if (init_fn && init_fn(np))
|
|
pr_err("Failed to initialise IOMMU %pOF\n", np);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
postcore_initcall_sync(of_iommu_init);
|