Add helper functions to help do address translation for either the address
of the extended linear cache or its alias address. The translation function
attempt to detect an I/O hole in the proximity domain and adjusts the address
if the hole impacts the aliasing of the address. The range of the I/O hole
is retrieved by walking through the associated memory target resources.
Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx>
---
drivers/acpi/numa/hmat.c | 136 +++++++++++++++++++++++++++++++++++++++
include/linux/acpi.h | 14 ++++
2 files changed, 150 insertions(+)
diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index d299f8d7af8c..834314582f4c 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -152,6 +152,142 @@ int hmat_get_extended_linear_cache_size(struct resource *backing_res, int nid,
}
EXPORT_SYMBOL_NS_GPL(hmat_get_extended_linear_cache_size, CXL);
+static int alias_address_find_iohole(struct memory_target *target,
+ u64 address, u64 alias, struct range *hole)
+{
+ struct resource *alias_res = NULL;
+ struct resource *res, *prev;
+
+ *hole = (struct range) {
+ .start = 0,
+ .end = -1,
+ };
+
+ /* First find the resource that the address is in */
+ prev = target->memregions.child;
+ for (res = target->memregions.child; res; res = res->sibling) {
+ if (alias >= res->start && alias <= res->end) {
+ alias_res = res;
+ break;
+ }
+ prev = res;
+ }
+ if (!alias_res)
+ return -EINVAL;
+
+ /* No memory hole */
+ if (alias_res == prev)
+ return 0;
+
+ /* If address is within the current resource, no need to deal with memory hole */
+ if (address >= alias_res->start)
+ return 0;
+
+ *hole = (struct range) {
+ .start = prev->end + 1,
+ .end = alias_res->start - 1,
+ };
+
+ return 0;
+}
+
+int hmat_extended_linear_cache_alias_xlat(u64 address, u64 *alias, int nid)
+{
+ unsigned int pxm = node_to_pxm(nid);
+ struct memory_target *target;
+ struct range iohole;
+ int rc;
+
+ target = find_mem_target(pxm);
+ if (!target)
+ return -EINVAL;
+
+ rc = alias_address_find_iohole(target, address, *alias, &iohole);
+ if (rc)
+ return rc;
+
+ if (!range_len(&iohole))
+ return 0;
+
+ if (address < iohole.start) {
+ if (*alias > iohole.start) {
+ *alias = *alias + range_len(&iohole);
+ return 0;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(hmat_extended_linear_cache_alias_xlat, CXL);
+
+static int target_address_find_iohole(struct memory_target *target,
+ u64 address, u64 alias,
+ struct range *hole)
+{
+ struct resource *addr_res = NULL;
+ struct resource *res, *next;
+
+ *hole = (struct range) {
+ .start = 0,
+ .end = -1,
+ };
+
+ /* First find the resource that the address is in */
+ for (res = target->memregions.child; res; res = res->sibling) {
+ if (address >= res->start && address <= res->end) {
+ addr_res = res;
+ break;
+ }
+ }
+ if (!addr_res)
+ return -EINVAL;
+
+ next = res->sibling;
+ /* No memory hole after the region */
+ if (!next)
+ return 0;
+
+ /* If alias is within the current resource, no need to deal with memory hole */
+ if (alias <= addr_res->end)
+ return 0;
+
+ *hole = (struct range) {
+ .start = addr_res->end + 1,
+ .end = next->start - 1,
+ };
+
+ return 0;
+}
+
+int hmat_extended_linear_cache_address_xlat(u64 *address, u64 alias, int nid)
+{
+ unsigned int pxm = node_to_pxm(nid);
+ struct memory_target *target;
+ struct range iohole;
+ int rc;
+
+ target = find_mem_target(pxm);
+ if (!target)
+ return -EINVAL;
+
+ rc = target_address_find_iohole(target, *address, alias, &iohole);
+ if (rc)
+ return rc;
+
+ if (!range_len(&iohole))
+ return 0;
+
+ if (alias > iohole.end) {
+ if (*address < iohole.end) {
+ *address = *address - range_len(&iohole);
+ return 0;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(hmat_extended_linear_cache_address_xlat, CXL);
+
static struct memory_target *acpi_find_genport_target(u32 uid)
{
struct memory_target *target;
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 8ed72d431dca..704bdfc79f85 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -437,6 +437,8 @@ int thermal_acpi_critical_trip_temp(struct acpi_device *adev, int *ret_temp);
int acpi_get_genport_coordinates(u32 uid, struct access_coordinate *coord);
int hmat_get_extended_linear_cache_size(struct resource *backing_res, int nid,
resource_size_t *size);
+int hmat_extended_linear_cache_alias_xlat(u64 address, u64 *alias, int nid);
+int hmat_extended_linear_cache_address_xlat(u64 *address, u64 alias, int nid);
#else
static inline int acpi_get_genport_coordinates(u32 uid,
struct access_coordinate *coord)
@@ -449,6 +451,18 @@ static inline int hmat_get_extended_linear_cache_size(struct resource *backing_r
{
return -EOPNOTSUPP;
}
+
+static inline int hmat_extended_linear_cache_alias_xlat(u64 address,
+ u64 *alias, int nid)
+{
+ return -EOPNOTSUPP;
+}
+
+static inline int hmat_extended_linear_cache_address_xlat(u64 *address,
+ u64 alias, int nid)
+{
+ return -EOPNOTSUPP;
+}
#endif
#ifdef CONFIG_ACPI_NUMA
--
2.46.1
