diff --git a/drivers/acpi/acpica/dbdisply.c b/drivers/acpi/acpica/dbdisply.c
index f2df416d0d2d..d41eb9e67500 100644
--- a/drivers/acpi/acpica/dbdisply.c
+++ b/drivers/acpi/acpica/dbdisply.c
@@ -51,6 +51,8 @@ static acpi_adr_space_type acpi_gbl_space_id_list[] = {
 	ACPI_ADR_SPACE_IPMI,
 	ACPI_ADR_SPACE_GPIO,
 	ACPI_ADR_SPACE_GSBUS,
+	ACPI_ADR_SPACE_PLATFORM_COMM,
+	ACPI_ADR_SPACE_PLATFORM_RT,
 	ACPI_ADR_SPACE_DATA_TABLE,
 	ACPI_ADR_SPACE_FIXED_HARDWARE
 };
diff --git a/drivers/acpi/acpica/utdecode.c b/drivers/acpi/acpica/utdecode.c
index 177ab88d95de..ed9aedf604a1 100644
--- a/drivers/acpi/acpica/utdecode.c
+++ b/drivers/acpi/acpica/utdecode.c
@@ -78,7 +78,8 @@ const char *acpi_gbl_region_types[ACPI_NUM_PREDEFINED_REGIONS] = {
 	"IPMI",			/* 0x07 */
 	"GeneralPurposeIo",	/* 0x08 */
 	"GenericSerialBus",	/* 0x09 */
-	"PCC"			/* 0x0A */
+	"PCC",			/* 0x0A */
+	"PlatformRtMechanism"	/* 0x0B */
 };
 
 const char *acpi_ut_get_region_name(u8 space_id)
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index 1dc8d262035b..459d6981ca96 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -12,7 +12,7 @@
 
 /* Current ACPICA subsystem version in YYYYMMDD format */
 
-#define ACPI_CA_VERSION                 0x20200430
+#define ACPI_CA_VERSION                 0x20200528
 
 #include <acpi/acconfig.h>
 #include <acpi/actypes.h>
diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index 4defed58ea33..aa236b9e6f24 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -815,8 +815,9 @@ typedef u8 acpi_adr_space_type;
 #define ACPI_ADR_SPACE_GPIO             (acpi_adr_space_type) 8
 #define ACPI_ADR_SPACE_GSBUS            (acpi_adr_space_type) 9
 #define ACPI_ADR_SPACE_PLATFORM_COMM    (acpi_adr_space_type) 10
+#define ACPI_ADR_SPACE_PLATFORM_RT      (acpi_adr_space_type) 11
 
-#define ACPI_NUM_PREDEFINED_REGIONS     11
+#define ACPI_NUM_PREDEFINED_REGIONS     12
 
 /*
  * Special Address Spaces
diff --git a/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c b/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
index 5aaddc79adf7..dd38c2b2e1b4 100644
--- a/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
+++ b/tools/power/acpi/os_specific/service_layers/oslinuxtbl.c
@@ -35,7 +35,7 @@ static acpi_status osl_add_table_to_list(char *signature, u32 instance);
 static acpi_status
 osl_read_table_from_file(char *filename,
 			 acpi_size file_offset,
-			 char *signature, struct acpi_table_header **table);
+			 struct acpi_table_header **table);
 
 static acpi_status
 osl_map_table(acpi_size address,
@@ -1184,8 +1184,6 @@ osl_table_name_from_file(char *filename, char *signature, u32 *instance)
  *
  * PARAMETERS:  filename            - File that contains the desired table
  *              file_offset         - Offset of the table in file
- *              signature           - Optional ACPI Signature for desired table.
- *                                    A null terminated 4-character string.
  *              table               - Where a pointer to the table is returned
  *
  * RETURN:      Status; Table buffer is returned if AE_OK.
@@ -1197,7 +1195,7 @@ osl_table_name_from_file(char *filename, char *signature, u32 *instance)
 static acpi_status
 osl_read_table_from_file(char *filename,
 			 acpi_size file_offset,
-			 char *signature, struct acpi_table_header **table)
+			 struct acpi_table_header **table)
 {
 	FILE *table_file;
 	struct acpi_table_header header;
@@ -1225,6 +1223,8 @@ osl_read_table_from_file(char *filename,
 		goto exit;
 	}
 
+#ifdef ACPI_OBSOLETE_FUNCTIONS
+
 	/* If signature is specified, it must match the table */
 
 	if (signature) {
@@ -1244,6 +1244,7 @@ osl_read_table_from_file(char *filename,
 			goto exit;
 		}
 	}
+#endif
 
 	table_length = ap_get_table_length(&header);
 	if (table_length == 0) {
@@ -1366,7 +1367,7 @@ osl_get_customized_table(char *pathname,
 	/* There is no physical address saved for customized tables, use zero */
 
 	*address = 0;
-	status = osl_read_table_from_file(table_filename, 0, NULL, table);
+	status = osl_read_table_from_file(table_filename, 0, table);
 
 	return (status);
 }