From patchwork Thu Jun 16 09:01:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 582774 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3DD64C433EF for ; Thu, 16 Jun 2022 09:01:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232295AbiFPJBY (ORCPT ); Thu, 16 Jun 2022 05:01:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56608 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231800AbiFPJBV (ORCPT ); Thu, 16 Jun 2022 05:01:21 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id DB038192B5 for ; Thu, 16 Jun 2022 02:01:19 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BB0A913D5; Thu, 16 Jun 2022 02:01:19 -0700 (PDT) Received: from usa.arm.com (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 7F95C3F7F5; Thu, 16 Jun 2022 02:01:18 -0700 (PDT) From: Sudeep Holla To: linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Sudeep Holla , "Rafael J . Wysocki" , Lorenzo Pieralisi , Catalin Marinas , Will Deacon Subject: [PATCH 1/3] ACPICA: Add support for FFH Opregion special context data Date: Thu, 16 Jun 2022 10:01:04 +0100 Message-Id: <20220616090106.2154906-2-sudeep.holla@arm.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220616090106.2154906-1-sudeep.holla@arm.com> References: <20220616090106.2154906-1-sudeep.holla@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org FFH(Fixed Function Hardware) Opregion is approved to be added in ACPIC 6.5 via code first approach[1]. It requires special context data similar to GPIO and Generic Serial Bus as it needs to know platform specific offset and length. Add support for the special context data needed by FFH Opregion. FFH OpRegion enables advanced use of FFH on some architectures. For example, it could be used to easily proxy AML code to architecture-specific behavior (to ensure it is OS initiated) Actual behavior of FFH is ofcourse architecture specific and depends on the FFH bindings. The offset and length could have arch specific meaning or usage. [1] https://bugzilla.tianocore.org/show_bug.cgi?id=3598 Signed-off-by: Sudeep Holla --- drivers/acpi/acpica/evregion.c | 8 ++++++++ drivers/acpi/acpica/exfield.c | 8 ++++++-- drivers/acpi/acpica/exserial.c | 6 ++++++ include/acpi/acconfig.h | 2 ++ include/acpi/actypes.h | 7 +++++++ 5 files changed, 29 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/acpica/evregion.c b/drivers/acpi/acpica/evregion.c index b96b3a7e78e5..d5aed3249630 100644 --- a/drivers/acpi/acpica/evregion.c +++ b/drivers/acpi/acpica/evregion.c @@ -172,6 +172,14 @@ acpi_ev_address_space_dispatch(union acpi_operand_object *region_obj, ctx->subspace_id = (u8)region_obj->region.address; } + if (region_obj->region.space_id == + ACPI_ADR_SPACE_FIXED_HARDWARE) { + struct acpi_ffh_info *ctx = + handler_desc->address_space.context; + + ctx->offset = region_obj->region.address; + ctx->length = region_obj->region.length; + } /* * We must exit the interpreter because the region setup will * potentially execute control methods (for example, the _REG method diff --git a/drivers/acpi/acpica/exfield.c b/drivers/acpi/acpica/exfield.c index 2b89a496de65..657f4002f9dc 100644 --- a/drivers/acpi/acpica/exfield.c +++ b/drivers/acpi/acpica/exfield.c @@ -141,7 +141,9 @@ acpi_ex_read_data_from_field(struct acpi_walk_state *walk_state, || obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_IPMI || obj_desc->field.region_obj->region.space_id == - ACPI_ADR_SPACE_PLATFORM_RT)) { + ACPI_ADR_SPACE_PLATFORM_RT + || obj_desc->field.region_obj->region.space_id == + ACPI_ADR_SPACE_FIXED_HARDWARE)) { /* SMBus, GSBus, IPMI serial */ @@ -305,7 +307,9 @@ acpi_ex_write_data_to_field(union acpi_operand_object *source_desc, || obj_desc->field.region_obj->region.space_id == ACPI_ADR_SPACE_IPMI || obj_desc->field.region_obj->region.space_id == - ACPI_ADR_SPACE_PLATFORM_RT)) { + ACPI_ADR_SPACE_PLATFORM_RT + || obj_desc->field.region_obj->region.space_id == + ACPI_ADR_SPACE_FIXED_HARDWARE)) { /* SMBus, GSBus, IPMI serial */ diff --git a/drivers/acpi/acpica/exserial.c b/drivers/acpi/acpica/exserial.c index 4da20d7845df..fd63f2042514 100644 --- a/drivers/acpi/acpica/exserial.c +++ b/drivers/acpi/acpica/exserial.c @@ -323,6 +323,12 @@ acpi_ex_write_serial_bus(union acpi_operand_object *source_desc, function = ACPI_WRITE; break; + case ACPI_ADR_SPACE_FIXED_HARDWARE: + + buffer_length = ACPI_FFH_INPUT_BUFFER_SIZE; + function = ACPI_WRITE; + break; + default: return_ACPI_STATUS(AE_AML_INVALID_SPACE_ID); } diff --git a/include/acpi/acconfig.h b/include/acpi/acconfig.h index c3ae3ea88e17..02e57191c1fd 100644 --- a/include/acpi/acconfig.h +++ b/include/acpi/acconfig.h @@ -190,6 +190,8 @@ #define ACPI_PRM_INPUT_BUFFER_SIZE 26 +#define ACPI_FFH_INPUT_BUFFER_SIZE 144 + /* _sx_d and _sx_w control methods */ #define ACPI_NUM_sx_d_METHODS 4 diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index 3491e454b2ab..1b4f81f1ac5d 100644 --- a/include/acpi/actypes.h +++ b/include/acpi/actypes.h @@ -1115,6 +1115,13 @@ struct acpi_pcc_info { u8 *internal_buffer; }; +/* Special Context data for FFH Opregion (ACPI 6.5) */ + +struct acpi_ffh_info { + u64 offset; + u64 length; +}; + typedef acpi_status (*acpi_adr_space_setup) (acpi_handle region_handle, u32 function, From patchwork Thu Jun 16 09:01:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 582295 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C645CCA47A for ; Thu, 16 Jun 2022 09:01:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230145AbiFPJBY (ORCPT ); Thu, 16 Jun 2022 05:01:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232036AbiFPJBW (ORCPT ); Thu, 16 Jun 2022 05:01:22 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 75D9E2DD4A for ; Thu, 16 Jun 2022 02:01:21 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5ECE61474; Thu, 16 Jun 2022 02:01:21 -0700 (PDT) Received: from usa.arm.com (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id DFA733F7F5; Thu, 16 Jun 2022 02:01:19 -0700 (PDT) From: Sudeep Holla To: linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Sudeep Holla , "Rafael J . Wysocki" , Lorenzo Pieralisi , Catalin Marinas , Will Deacon Subject: [PATCH 2/3] ACPI: Implement a generic FFH Opregion handler Date: Thu, 16 Jun 2022 10:01:05 +0100 Message-Id: <20220616090106.2154906-3-sudeep.holla@arm.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220616090106.2154906-1-sudeep.holla@arm.com> References: <20220616090106.2154906-1-sudeep.holla@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org This registers the FFH OpRegion handler before ACPI tables are loaded. The platform support for the same is checked via Platform-Wide OSPM Capabilities(OSC) before registering the OpRegion handler. It relies on the special context data passed to offset and the length. However the interpretation of the values is platform/architecture specific. This generic handler just passed all the information to the platform/architecture specific callback. It also implements the default callbacks which return as not supported. Signed-off-by: Sudeep Holla --- drivers/acpi/Kconfig | 10 ++++++++ drivers/acpi/Makefile | 1 + drivers/acpi/acpi_ffh.c | 55 +++++++++++++++++++++++++++++++++++++++++ drivers/acpi/bus.c | 6 +++++ include/linux/acpi.h | 7 ++++++ 5 files changed, 79 insertions(+) create mode 100644 drivers/acpi/acpi_ffh.c diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 1e34f846508f..c1cf40b7d22b 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -567,6 +567,16 @@ config ACPI_PCC Enable this feature if you want to set up and install the PCC Address Space handler to handle PCC OpRegion in the firmware. +config ACPI_FFH + bool "ACPI FFH Address Space" + default n + help + The FFH(Fixed Function Hardware) Address Space also referred as FFH + Operation Region allows to define platform specific opregion. + + Enable this feature if you want to set up and install the FFH Address + Space handler to handle FFH OpRegion in the firmware. + source "drivers/acpi/pmic/Kconfig" config ACPI_VIOT diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index b5a8d3e00a52..d2fc0587e218 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -68,6 +68,7 @@ acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o acpi-$(CONFIG_ACPI_PRMT) += prmt.o acpi-$(CONFIG_ACPI_PCC) += acpi_pcc.o +acpi-$(CONFIG_ACPI_FFH) += acpi_ffh.o # Address translation acpi-$(CONFIG_ACPI_ADXL) += acpi_adxl.o diff --git a/drivers/acpi/acpi_ffh.c b/drivers/acpi/acpi_ffh.c new file mode 100644 index 000000000000..19aff808bbb8 --- /dev/null +++ b/drivers/acpi/acpi_ffh.c @@ -0,0 +1,55 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Author: Sudeep Holla + * Copyright 2022 Arm Limited + */ +#include +#include +#include +#include +#include + +#include + +static struct acpi_ffh_info ffh_ctx; + +int __weak acpi_ffh_address_space_arch_setup(void *handler_ctxt, + void **region_ctxt) +{ + return -EOPNOTSUPP; +} + +int __weak acpi_ffh_address_space_arch_handler(acpi_integer *value, + void *region_context) +{ + return -EOPNOTSUPP; +} + +static acpi_status +acpi_ffh_address_space_setup(acpi_handle region_handle, u32 function, + void *handler_context, void **region_context) +{ + return acpi_ffh_address_space_arch_setup(handler_context, + region_context); +} + +static acpi_status +acpi_ffh_address_space_handler(u32 function, acpi_physical_address addr, + u32 bits, acpi_integer *value, + void *handler_context, void *region_context) +{ + return acpi_ffh_address_space_arch_handler(value, region_context); +} + +void __init acpi_init_ffh(void) +{ + acpi_status status; + + status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT, + ACPI_ADR_SPACE_FIXED_HARDWARE, + &acpi_ffh_address_space_handler, + &acpi_ffh_address_space_setup, + &ffh_ctx); + if (ACPI_FAILURE(status)) + pr_alert("OperationRegion handler could not be installed\n"); +} diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index 86fa61a21826..84734c8cc714 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -298,6 +298,8 @@ EXPORT_SYMBOL_GPL(osc_cpc_flexible_adr_space_confirmed); bool osc_sb_native_usb4_support_confirmed; EXPORT_SYMBOL_GPL(osc_sb_native_usb4_support_confirmed); +bool osc_sb_ffh_opregion_support_confirmed; + bool osc_sb_cppc_not_supported; static u8 sb_uuid_str[] = "0811B06E-4A27-44F9-8D60-3CBBC22E7B48"; @@ -384,6 +386,8 @@ static void acpi_bus_osc_negotiate_platform_control(void) capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_NATIVE_USB4_SUPPORT; osc_cpc_flexible_adr_space_confirmed = capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_CPC_FLEXIBLE_ADR_SPACE; + osc_sb_ffh_opregion_support_confirmed = + capbuf_ret[OSC_SUPPORT_DWORD] & OSC_SB_FFH_OPR_SUPPORT; } kfree(context.ret.pointer); @@ -1397,6 +1401,8 @@ static int __init acpi_init(void) disable_acpi(); return result; } + if (osc_sb_ffh_opregion_support_confirmed) + acpi_init_ffh(); pci_mmcfg_late_init(); acpi_iort_init(); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 4f82a5bc6d98..471c42a6044c 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -580,6 +580,7 @@ acpi_status acpi_run_osc(acpi_handle handle, struct acpi_osc_context *context); #define OSC_SB_CPC_FLEXIBLE_ADR_SPACE 0x00004000 #define OSC_SB_NATIVE_USB4_SUPPORT 0x00040000 #define OSC_SB_PRM_SUPPORT 0x00200000 +#define OSC_SB_FFH_OPR_SUPPORT 0x00400000 extern bool osc_sb_apei_support_acked; extern bool osc_pc_lpi_support_confirmed; @@ -1463,6 +1464,12 @@ void acpi_init_pcc(void); static inline void acpi_init_pcc(void) { } #endif +#ifdef CONFIG_ACPI_FFH +void acpi_init_ffh(void); +#else +static inline void acpi_init_ffh(void) { } +#endif + #ifdef CONFIG_ACPI extern void acpi_device_notify(struct device *dev); extern void acpi_device_notify_remove(struct device *dev); From patchwork Thu Jun 16 09:01:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 582294 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9480BC43334 for ; Thu, 16 Jun 2022 09:01:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231800AbiFPJBZ (ORCPT ); Thu, 16 Jun 2022 05:01:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232156AbiFPJBX (ORCPT ); Thu, 16 Jun 2022 05:01:23 -0400 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id D0CB8192B5 for ; Thu, 16 Jun 2022 02:01:22 -0700 (PDT) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id B153812FC; Thu, 16 Jun 2022 02:01:22 -0700 (PDT) Received: from usa.arm.com (e103737-lin.cambridge.arm.com [10.1.197.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 83A643F7F5; Thu, 16 Jun 2022 02:01:21 -0700 (PDT) From: Sudeep Holla To: linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: Sudeep Holla , "Rafael J . Wysocki" , Lorenzo Pieralisi , Catalin Marinas , Will Deacon Subject: [PATCH 3/3] arm64: Add architecture specific ACPI FFH Opregion callbacks Date: Thu, 16 Jun 2022 10:01:06 +0100 Message-Id: <20220616090106.2154906-4-sudeep.holla@arm.com> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220616090106.2154906-1-sudeep.holla@arm.com> References: <20220616090106.2154906-1-sudeep.holla@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org FFH Operation Region space can be used to trigger SMC or HVC calls, using the Arm SMC Calling Convention (SMCCC). The choice of conduit (SMC or HVC) is based on what the kernel choose based on PSCI as with any other users of SMCCC within the kernel. Function identifiers only the SMCCC SiP Service, OEM Service and FF-A specific call range. Offset can be either 0(32 bit calling convention) or 1(64 bit calling convention). The length must be set with the range applicable based on the value of the offset. Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Sudeep Holla Acked-by: Catalin Marinas --- arch/arm64/kernel/acpi.c | 104 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index e4dea8db6924..3eb64d443ab0 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -13,6 +13,7 @@ #define pr_fmt(fmt) "ACPI: " fmt #include +#include #include #include #include @@ -411,3 +412,106 @@ void arch_reserve_mem_area(acpi_physical_address addr, size_t size) { memblock_mark_nomap(addr, size); } + +#ifdef CONFIG_ACPI_FFH +/* + * Implements ARM64 specific callbacks to support ACPI FFH Operation Region as + * specified in https://developer.arm.com/docs/den0048/latest + */ +struct acpi_ffh_data { + struct acpi_ffh_info info; + void (*invoke_ffh_fn)(unsigned long, unsigned long, unsigned long, + unsigned long, unsigned long, unsigned long, + unsigned long, unsigned long, + struct arm_smccc_res *, struct arm_smccc_quirk *); + void (*invoke_ffh64_fn)(const struct arm_smccc_1_2_regs *, + struct arm_smccc_1_2_regs *); +}; + +int acpi_ffh_address_space_arch_setup(void *handler_ctxt, void **region_ctxt) +{ + enum arm_smccc_conduit conduit; + struct acpi_ffh_data *ffh_ctxt; + + ffh_ctxt = kzalloc(sizeof(*ffh_ctxt), GFP_KERNEL); + if (!ffh_ctxt) + return -ENOMEM; + + if (arm_smccc_get_version() < ARM_SMCCC_VERSION_1_2) + return -EOPNOTSUPP; + + conduit = arm_smccc_1_1_get_conduit(); + if (conduit == SMCCC_CONDUIT_NONE) { + pr_err("%s: invalid SMCCC conduit\n", __func__); + return -EOPNOTSUPP; + } + + if (conduit == SMCCC_CONDUIT_SMC) { + ffh_ctxt->invoke_ffh_fn = __arm_smccc_smc; + ffh_ctxt->invoke_ffh64_fn = arm_smccc_1_2_smc; + } else { + ffh_ctxt->invoke_ffh_fn = __arm_smccc_hvc; + ffh_ctxt->invoke_ffh64_fn = arm_smccc_1_2_hvc; + } + + memcpy(ffh_ctxt, handler_ctxt, sizeof(ffh_ctxt->info)); + + *region_ctxt = ffh_ctxt; + return AE_OK; +} + +static bool acpi_ffh_smccc_owner_allowed(u32 fid) +{ + int owner = ARM_SMCCC_OWNER_NUM(fid); + + if (owner == ARM_SMCCC_OWNER_STANDARD || + owner == ARM_SMCCC_OWNER_SIP || owner == ARM_SMCCC_OWNER_OEM) + return true; + + return false; +} + +int acpi_ffh_address_space_arch_handler(acpi_integer *value, void *region_context) +{ + int ret = 0; + struct acpi_ffh_data *ffh_ctxt = region_context; + + if (ffh_ctxt->info.offset == 0) { + /* SMC/HVC 32bit call */ + struct arm_smccc_res res; + u32 a[8] = { 0 }, *ptr = (u32 *)value; + + if (!ARM_SMCCC_IS_FAST_CALL(*ptr) || ARM_SMCCC_IS_64(*ptr) || + !acpi_ffh_smccc_owner_allowed(*ptr) || + ffh_ctxt->info.length > 32) { + ret = AE_ERROR; + } else { + int idx, len = ffh_ctxt->info.length >> 2; + + for (idx = 0; idx < len; idx++) + a[idx] = *(ptr + idx); + + ffh_ctxt->invoke_ffh_fn(a[0], a[1], a[2], a[3], a[4], + a[5], a[6], a[7], &res, NULL); + memcpy(value, &res, sizeof(res)); + } + + } else if (ffh_ctxt->info.offset == 1) { + /* SMC/HVC 64bit call */ + struct arm_smccc_1_2_regs *r = (struct arm_smccc_1_2_regs *)value; + + if (!ARM_SMCCC_IS_FAST_CALL(r->a0) || !ARM_SMCCC_IS_64(r->a0) || + !acpi_ffh_smccc_owner_allowed(r->a0) || + ffh_ctxt->info.length > sizeof(*r)) { + ret = AE_ERROR; + } else { + ffh_ctxt->invoke_ffh64_fn(r, r); + memcpy(value, r, ffh_ctxt->info.length); + } + } else { + ret = AE_ERROR; + } + + return ret; +} +#endif /* CONFIG_ACPI_FFH */