From patchwork Tue Nov 2 18:25:42 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 12599479 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F263DC433F5 for ; Tue, 2 Nov 2021 18:26:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D095C61050 for ; Tue, 2 Nov 2021 18:26:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235040AbhKBS2x (ORCPT ); Tue, 2 Nov 2021 14:28:53 -0400 Received: from foss.arm.com ([217.140.110.172]:41720 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230361AbhKBS2t (ORCPT ); Tue, 2 Nov 2021 14:28:49 -0400 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 0EBE811B3; Tue, 2 Nov 2021 11:26:14 -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 29BA73F7B4; Tue, 2 Nov 2021 11:26:13 -0700 (PDT) From: Sudeep Holla To: Robert Moore Cc: Sudeep Holla , "Rafael J . Wysocki" , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, devel@acpica.org Subject: [PATCH 3/3] ACPI: PCC: Implement OperationRegion handler for the PCC Type 3 subtype Date: Tue, 2 Nov 2021 18:25:42 +0000 Message-Id: <20211102182542.3460787-4-sudeep.holla@arm.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211102182542.3460787-1-sudeep.holla@arm.com> References: <20211102182542.3460787-1-sudeep.holla@arm.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org PCC OpRegion provides a mechanism to communicate with the platform directly from the AML. PCCT provides the list of PCC channel available in the platform, a subset or all of them can be used in PCC Opregion. This patch registers the PCC OpRegion handler before ACPI tables are loaded. This relies on the special context data passed to identify and setup the PCC channel before the OpRegion handler is executed for the first time. Typical PCC Opregion declaration looks like this: OperationRegion (PFRM, PCC, 2, 0x74) Field (PFRM, ByteAcc, NoLock, Preserve) { SIGN, 32, FLGS, 32, LEN, 32, CMD, 32, DATA, 800 } It contains 4 named double words followed by 100 bytes of buffer names DATA. ASL can fill out the buffer something like: /* Create global or local buffer */ Name (BUFF, Buffer (0x0C){}) /* Create double word fields over the buffer */ CreateDWordField (BUFF, 0x0, WD0) CreateDWordField (BUFF, 0x04, WD1) CreateDWordField (BUFF, 0x08, WD2) /* Fill the named fields */ WD0 = 0x50434300 SIGN = BUFF WD0 = 1 FLGS = BUFF WD0 = 0x10 LEN = BUFF /* Fill the payload in the DATA buffer */ WD0 = 0 WD1 = 0x08 WD2 = 0 DATA = BUFF /* Write to CMD field to trigger handler */ WD0 = 0x4404 CMD = BUFF This buffer is recieved by acpi_pcc_opregion_space_handler. This handler will fetch the commplete buffer via internal_pcc_buffer. The setup handler will receive the special PCC context data which will contain the PCC channel index which used to setup the channel. The buffer pointer and length is saved in region context which is then used in the handler. Signed-off-by: Sudeep Holla --- drivers/acpi/Kconfig | 5 ++ drivers/acpi/Makefile | 1 + drivers/acpi/bus.c | 1 + drivers/acpi/pcc_opregion.c | 111 ++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 6 ++ 5 files changed, 124 insertions(+) create mode 100644 drivers/acpi/pcc_opregion.c diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 1da360c51d66..c2998e489cec 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -524,6 +524,11 @@ config ACPI_PPTT bool endif +config ACPI_PCC_OPREGION + bool "PCC Opregion" + depends on PCC + default y + source "drivers/acpi/pmic/Kconfig" config ACPI_VIOT diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 3018714e87d9..d010ed3f4937 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -67,6 +67,7 @@ acpi-$(CONFIG_ACPI_LPIT) += acpi_lpit.o acpi-$(CONFIG_ACPI_GENERIC_GSI) += irq.o acpi-$(CONFIG_ACPI_WATCHDOG) += acpi_watchdog.o acpi-$(CONFIG_ACPI_PRMT) += prmt.o +acpi-$(CONFIG_ACPI_PCC_OPREGION) += pcc_opregion.o # Address translation acpi-$(CONFIG_ACPI_ADXL) += acpi_adxl.o diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index fa923a929224..5e1eea7fb6f4 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -1320,6 +1320,7 @@ static int __init acpi_init(void) pr_debug("%s: kset create error\n", __func__); init_prmt(); + init_pcc_opregion(); result = acpi_bus_init(); if (result) { kobject_put(acpi_kobj); diff --git a/drivers/acpi/pcc_opregion.c b/drivers/acpi/pcc_opregion.c new file mode 100644 index 000000000000..c965ce555bd0 --- /dev/null +++ b/drivers/acpi/pcc_opregion.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Author: Sudeep Holla + * Copyright 2021 Arm Limited + * + * pcc_opregion.c + * + */ +#include +#include +#include +#include +#include + +#include + +struct pcc_data { + struct pcc_mbox_chan *pcc_chan; + void __iomem *pcc_comm_addr; + struct completion done; + struct mbox_client cl; + struct acpi_pcc_info ctx; +}; + +struct acpi_pcc_info pcc_ctx; + +static void pcc_rx_callback(struct mbox_client *cl, void *m) +{ + struct pcc_data *data = container_of(cl, struct pcc_data, cl); + + complete(&data->done); +} + +static acpi_status +acpi_pcc_opregion_setup(acpi_handle region_handle, u32 function, + void *handler_context, void **region_context) +{ + struct pcc_data *data; + struct acpi_pcc_info *ctx = handler_context; + struct pcc_mbox_chan *pcc_chan; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return_ACPI_STATUS(AE_NO_MEMORY); + + data->cl.rx_callback = pcc_rx_callback; + data->cl.knows_txdone = true; + data->ctx.length = ctx->length; + data->ctx.subspace_id = ctx->subspace_id; + data->ctx.internal_buffer = ctx->internal_buffer; + + init_completion(&data->done); + data->pcc_chan = pcc_mbox_request_channel(&data->cl, ctx->subspace_id); + if (IS_ERR(data->pcc_chan)) { + pr_err("Failed to find PCC channel for subspace %d\n", + ctx->subspace_id); + return_ACPI_STATUS(AE_NOT_FOUND); + } + + pcc_chan = data->pcc_chan; + data->pcc_comm_addr = acpi_os_ioremap(pcc_chan->shmem_base_addr, + pcc_chan->shmem_size); + if (!data->pcc_comm_addr) { + pr_err("Failed to ioremap PCC comm region mem for %d\n", + ctx->subspace_id); + return_ACPI_STATUS(AE_NO_MEMORY); + } + + *region_context = data; + return_ACPI_STATUS(AE_OK); +} + +static acpi_status +acpi_pcc_opregion_space_handler(u32 function, acpi_physical_address addr, + u32 bits, acpi_integer *value, + void *handler_context, void *region_context) +{ + int ret; + struct pcc_data* data = region_context; + + reinit_completion(&data->done); + + /* Write to Shared Memory */ + memcpy_toio(data->pcc_comm_addr, (void *)value, data->ctx.length); + + ret = mbox_send_message(data->pcc_chan->mchan, NULL); + if (ret < 0) + return_ACPI_STATUS(AE_ERROR); + + if (data->pcc_chan->mchan->mbox->txdone_irq) + wait_for_completion(&data->done); + + mbox_client_txdone(data->pcc_chan->mchan, ret); + + memcpy_fromio(value, data->pcc_comm_addr, data->ctx.length); + + return_ACPI_STATUS(AE_OK); +} + +void __init init_pcc_opregion(void) +{ + acpi_status status; + + status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT, + ACPI_ADR_SPACE_PLATFORM_COMM, + &acpi_pcc_opregion_space_handler, + &acpi_pcc_opregion_setup, + &pcc_ctx); + if (ACPI_FAILURE(status)) + pr_alert("OperationRegion handler could not be installed\n"); +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index fbc2146050a4..7dd565294408 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1384,6 +1384,12 @@ static inline int find_acpi_cpu_cache_topology(unsigned int cpu, int level) } #endif +#ifdef CONFIG_ACPI_PCC_OPREGION +void init_pcc_opregion(void); +#else +static inline void init_pcc_opregion(void) { } +#endif + #ifdef CONFIG_ACPI extern void acpi_device_notify(struct device *dev); extern void acpi_device_notify_remove(struct device *dev);