1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Author: Sudeep Holla <sudeep.holla@arm.com> 4 * Copyright 2022 Arm Limited 5 */ 6 #include <linux/kernel.h> 7 #include <linux/acpi.h> 8 #include <linux/completion.h> 9 #include <linux/idr.h> 10 #include <linux/io.h> 11 12 #include <linux/arm-smccc.h> 13 14 static struct acpi_ffh_info ffh_ctx; 15 16 int __weak acpi_ffh_address_space_arch_setup(void *handler_ctxt, 17 void **region_ctxt) 18 { 19 return -EOPNOTSUPP; 20 } 21 22 int __weak acpi_ffh_address_space_arch_handler(acpi_integer *value, 23 void *region_context) 24 { 25 return -EOPNOTSUPP; 26 } 27 28 static acpi_status 29 acpi_ffh_address_space_setup(acpi_handle region_handle, u32 function, 30 void *handler_context, void **region_context) 31 { 32 return acpi_ffh_address_space_arch_setup(handler_context, 33 region_context); 34 } 35 36 static acpi_status 37 acpi_ffh_address_space_handler(u32 function, acpi_physical_address addr, 38 u32 bits, acpi_integer *value, 39 void *handler_context, void *region_context) 40 { 41 return acpi_ffh_address_space_arch_handler(value, region_context); 42 } 43 44 void __init acpi_init_ffh(void) 45 { 46 acpi_status status; 47 48 status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT, 49 ACPI_ADR_SPACE_FIXED_HARDWARE, 50 &acpi_ffh_address_space_handler, 51 &acpi_ffh_address_space_setup, 52 &ffh_ctx); 53 if (ACPI_FAILURE(status)) 54 pr_alert("OperationRegion handler could not be installed\n"); 55 } 56