Commit 987068fc authored by Robin Murphy's avatar Robin Murphy Committed by Will Deacon

of/irq: Break out msi-map lookup (again)

The PCI msi-map code is already doing double-duty translating IDs and
retrieving MSI parents, which unsurprisingly is the same functionality
we need for the identically-formatted PCI iommu-map property. Drag the
core parsing routine up yet another layer into the general OF-PCI code,
and further generalise it for either kind of lookup in either flavour
of map property.
Acked-by: default avatarRob Herring <robh+dt@kernel.org>
Acked-by: default avatarMarc Zyngier <marc.zyngier@arm.com>
Tested-by: default avatarLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 6ec2392c
......@@ -26,6 +26,7 @@
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/string.h>
#include <linux/slab.h>
......@@ -592,87 +593,16 @@ static u32 __of_msi_map_rid(struct device *dev, struct device_node **np,
u32 rid_in)
{
struct device *parent_dev;
struct device_node *msi_controller_node;
struct device_node *msi_np = *np;
u32 map_mask, masked_rid, rid_base, msi_base, rid_len, phandle;
int msi_map_len;
bool matched;
u32 rid_out = rid_in;
const __be32 *msi_map = NULL;
/*
* Walk up the device parent links looking for one with a
* "msi-map" property.
*/
for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent) {
if (!parent_dev->of_node)
continue;
msi_map = of_get_property(parent_dev->of_node,
"msi-map", &msi_map_len);
if (!msi_map)
continue;
if (msi_map_len % (4 * sizeof(__be32))) {
dev_err(parent_dev, "Error: Bad msi-map length: %d\n",
msi_map_len);
return rid_out;
}
/* We have a good parent_dev and msi_map, let's use them. */
break;
}
if (!msi_map)
return rid_out;
/* The default is to select all bits. */
map_mask = 0xffffffff;
/*
* Can be overridden by "msi-map-mask" property. If
* of_property_read_u32() fails, the default is used.
*/
of_property_read_u32(parent_dev->of_node, "msi-map-mask", &map_mask);
masked_rid = map_mask & rid_in;
matched = false;
while (!matched && msi_map_len >= 4 * sizeof(__be32)) {
rid_base = be32_to_cpup(msi_map + 0);
phandle = be32_to_cpup(msi_map + 1);
msi_base = be32_to_cpup(msi_map + 2);
rid_len = be32_to_cpup(msi_map + 3);
if (rid_base & ~map_mask) {
dev_err(parent_dev,
"Invalid msi-map translation - msi-map-mask (0x%x) ignores rid-base (0x%x)\n",
map_mask, rid_base);
return rid_out;
}
msi_controller_node = of_find_node_by_phandle(phandle);
matched = (masked_rid >= rid_base &&
masked_rid < rid_base + rid_len);
if (msi_np)
matched &= msi_np == msi_controller_node;
if (matched && !msi_np) {
*np = msi_np = msi_controller_node;
for (parent_dev = dev; parent_dev; parent_dev = parent_dev->parent)
if (!of_pci_map_rid(parent_dev->of_node, rid_in, "msi-map",
"msi-map-mask", np, &rid_out))
break;
}
of_node_put(msi_controller_node);
msi_map_len -= 4 * sizeof(__be32);
msi_map += 4;
}
if (!matched)
return rid_out;
rid_out = masked_rid - rid_base + msi_base;
dev_dbg(dev,
"msi-map at: %s, using mask %08x, rid-base: %08x, msi-base: %08x, length: %08x, rid: %08x -> %08x\n",
dev_name(parent_dev), map_mask, rid_base, msi_base,
rid_len, rid_in, rid_out);
return rid_out;
}
......
......@@ -308,3 +308,105 @@ struct msi_controller *of_pci_find_msi_chip_by_node(struct device_node *of_node)
EXPORT_SYMBOL_GPL(of_pci_find_msi_chip_by_node);
#endif /* CONFIG_PCI_MSI */
/**
* of_pci_map_rid - Translate a requester ID through a downstream mapping.
* @np: root complex device node.
* @rid: PCI 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 a PCI 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_pci_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("%s: Error: Bad %s length: %d\n", np->full_name,
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("%s: Invalid %s translation - %s-mask (0x%x) ignores rid-base (0x%x)\n",
np->full_name, 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("%s: %s, using mask %08x, rid-base: %08x, out-base: %08x, length: %08x, rid: %08x -> %08x\n",
np->full_name, map_name, map_mask, rid_base, out_base,
rid_len, rid, *id_out);
return 0;
}
pr_err("%s: Invalid %s translation - no match for rid 0x%x on %s\n",
np->full_name, map_name, rid,
target && *target ? (*target)->full_name : "any target");
return -EFAULT;
}
......@@ -17,6 +17,9 @@ int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin);
int of_pci_parse_bus_range(struct device_node *node, struct resource *res);
int of_get_pci_domain_nr(struct device_node *node);
void of_pci_check_probe_only(void);
int of_pci_map_rid(struct device_node *np, u32 rid,
const char *map_name, const char *map_mask_name,
struct device_node **target, u32 *id_out);
#else
static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq)
{
......@@ -52,6 +55,13 @@ of_get_pci_domain_nr(struct device_node *node)
return -1;
}
static inline int of_pci_map_rid(struct device_node *np, u32 rid,
const char *map_name, const char *map_mask_name,
struct device_node **target, u32 *id_out)
{
return -EINVAL;
}
static inline void of_pci_check_probe_only(void) { }
#endif
......
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