From patchwork Thu Jun 7 15:59:54 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: stuart hayes X-Patchwork-Id: 10453035 X-Patchwork-Delegate: andy.shevchenko@gmail.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 87BBD60375 for ; Thu, 7 Jun 2018 16:03:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7835D294C4 for ; Thu, 7 Jun 2018 16:03:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 6C40A29970; Thu, 7 Jun 2018 16:03:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E24A42995B for ; Thu, 7 Jun 2018 16:03:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934637AbeFGQA2 (ORCPT ); Thu, 7 Jun 2018 12:00:28 -0400 Received: from mail-ot0-f193.google.com ([74.125.82.193]:41250 "EHLO mail-ot0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933178AbeFGP77 (ORCPT ); Thu, 7 Jun 2018 11:59:59 -0400 Received: by mail-ot0-f193.google.com with SMTP id d19-v6so6581039oti.8; Thu, 07 Jun 2018 08:59:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:from:to:cc:references:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=7MeyJcmP+RmVXGlb3ok3oWmMX7V2GkaOBpRbaAuIoMk=; b=gi3zhuhOggaB0ubx+mB7RRF9TvoXkqZ//+iOCqgszr5vNO9OJFvHSe1AJEmWFtG55W t8/M9cfPKhoy3YA4z/RH0o1gzCuic5hqKCf/iHFeva0bD5nEj/JzugrGmS7gYKt7NMPa PdlqVY6+rT68F+7Cc5wrjP6qGivr2DfqysU0z+N7zKkAb2y1fYwQiSpXyB3VcoXJ9RBO t3kcYCFxbpJq7S1jq/G0FMVK4V2e8ikiNVkcOpSJTw4pV2zI3/HJNwT6lTB/GGy28QOL FyYToj/PuD8Lq0WR+Hv+llpiYWUdSRuKqiRS01+Q2xlIkNfBJqlcvgQuBNVlOIrHoBV/ m8Cw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=7MeyJcmP+RmVXGlb3ok3oWmMX7V2GkaOBpRbaAuIoMk=; b=W11z7QtRGYvnCPnB7EIA/80HCWomPgVLm39G+TT39nbPwDeBKLsTEbp8jmLXWpcItr Zwy90hw6Z1e4GfH4TQHJqjJieqAmLFjtKUo0E4gkwsBtcpC/oCk5Vntb7q/Shyb7uNdK rS5n8tIPF6Q19KAkj849vzzn8sWypkLF8rDq2O1n2Di6vc96INVukQJ3U22iGU2LS0kJ c0WsMndFIDwQAYcbYosd4yOT5KSNmCaH7lmOLEzeAEnCjikvpgCF9Kwml6Hv1T2ZXcye bsrUc8YkR7b9etKXs0c27KsC38FWJK7kFEmUp9ab+YRVPINKwePp9/6sKMSJy+GgkmeF Aq7g== X-Gm-Message-State: APt69E1QY1FMq6468I1KkJPetQqojOLtpdMhSyJ0n8MsxmTZonIV2EFf EUtZduiHWUXBUu2kazGniNGDVWbe X-Google-Smtp-Source: ADUXVKJd4i89CCTTyTvqKdnir/oMxjJmu4G2QilC6ulbFXjOQ2sTrMB02l1NdVsBr0ddO/MhQRz76A== X-Received: by 2002:a9d:338d:: with SMTP id u13-v6mr1428148otc.232.1528387198228; Thu, 07 Jun 2018 08:59:58 -0700 (PDT) Received: from [192.168.0.2] (cpe-24-27-59-32.austin.res.rr.com. [24.27.59.32]) by smtp.gmail.com with ESMTPSA id s144-v6sm8699006oie.17.2018.06.07.08.59.57 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 07 Jun 2018 08:59:57 -0700 (PDT) Subject: [PATCH resend v2] dcdbas: Add support for WSMT ACPI table From: Stuart Hayes To: Douglas_Warzecha@Dell.com Cc: mario.limonciello@dell.com, Jared_Dominguez@dell.com, linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org References: <45b8bde6-aaa8-3f3f-0528-81e5e931751c@gmail.com> Message-ID: Date: Thu, 7 Jun 2018 10:59:54 -0500 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <45b8bde6-aaa8-3f3f-0528-81e5e931751c@gmail.com> Content-Language: en-US X-Antivirus: Avast (VPS 180607-0, 06/07/2018), Outbound message X-Antivirus-Status: Clean Sender: platform-driver-x86-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP If the WSMT ACPI table is present and indicates that a fixed communication buffer should be used, use the firmware-specified buffer instead of allocating a buffer in memory for communications between the dcdbas driver and firmare. Signed-off-by: Stuart Hayes Tested-by: Mario Limonciello Acked-by: Doug Warzecha --- v2 Bumped driver version to 5.6.0-3.3 drivers/firmware/Kconfig | 2 +- drivers/firmware/dcdbas.c | 102 +++++++++++++++++++++++++++++++++++++++++++--- drivers/firmware/dcdbas.h | 11 +++++ 3 files changed, 109 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index b7c748248e53..a2bd6092bfa1 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -125,7 +125,7 @@ config DELL_RBU config DCDBAS tristate "Dell Systems Management Base Driver" - depends on X86 + depends on X86 && ACPI help The Dell Systems Management Base Driver provides a sysfs interface for systems management software to perform System Management diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c index 0bdea60c65dd..1699cfdcefe4 100644 --- a/drivers/firmware/dcdbas.c +++ b/drivers/firmware/dcdbas.c @@ -36,12 +36,13 @@ #include #include #include +#include #include #include "dcdbas.h" #define DRIVER_NAME "dcdbas" -#define DRIVER_VERSION "5.6.0-3.2" +#define DRIVER_VERSION "5.6.0-3.3" #define DRIVER_DESCRIPTION "Dell Systems Management Base Driver" static struct platform_device *dcdbas_pdev; @@ -49,19 +50,23 @@ static struct platform_device *dcdbas_pdev; static u8 *smi_data_buf; static dma_addr_t smi_data_buf_handle; static unsigned long smi_data_buf_size; +static unsigned long max_smi_data_buf_size = MAX_SMI_DATA_BUF_SIZE; static u32 smi_data_buf_phys_addr; static DEFINE_MUTEX(smi_data_lock); +static u8 *eps_buffer; static unsigned int host_control_action; static unsigned int host_control_smi_type; static unsigned int host_control_on_shutdown; +static bool wsmt_enabled; + /** * smi_data_buf_free: free SMI data buffer */ static void smi_data_buf_free(void) { - if (!smi_data_buf) + if (!smi_data_buf || wsmt_enabled) return; dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", @@ -86,7 +91,7 @@ static int smi_data_buf_realloc(unsigned long size) if (smi_data_buf_size >= size) return 0; - if (size > MAX_SMI_DATA_BUF_SIZE) + if (size > max_smi_data_buf_size) return -EINVAL; /* new buffer is needed */ @@ -169,7 +174,7 @@ static ssize_t smi_data_write(struct file *filp, struct kobject *kobj, { ssize_t ret; - if ((pos + count) > MAX_SMI_DATA_BUF_SIZE) + if ((pos + count) > max_smi_data_buf_size) return -EINVAL; mutex_lock(&smi_data_lock); @@ -323,7 +328,8 @@ static ssize_t smi_request_store(struct device *dev, break; case 1: /* Calling Interface SMI */ - smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer); + smi_cmd->ebx = smi_data_buf_phys_addr + + offsetof(struct smi_cmd, command_buffer); ret = dcdbas_smi_request(smi_cmd); if (!ret) ret = count; @@ -482,6 +488,85 @@ static void dcdbas_host_control(void) } } +/* WSMT */ + +static u8 checksum(u8 *buffer, u8 length) +{ + u8 sum = 0; + u8 *end = buffer + length; + + while (buffer < end) + sum = (u8)(sum + *(buffer++)); + return sum; +} + +static inline struct smm_eps_table *check_eps_table(u8 *addr) +{ + struct smm_eps_table *eps = (struct smm_eps_table *)addr; + + if (strncmp(SMM_EPS_SIG, eps->smm_comm_buff_anchor, 4) != 0) + return NULL; + + if (checksum(addr, eps->length) != 0) + return NULL; + + return eps; +} + +static int dcdbas_check_wsmt(void) +{ + struct acpi_table_wsmt *wsmt = NULL; + struct smm_eps_table *eps = NULL; + u8 *addr; + + acpi_get_table(ACPI_SIG_WSMT, 0, (struct acpi_table_header **)&wsmt); + if (!wsmt) + return 0; + + /* Check if WSMT ACPI table shows that protection is enabled */ + if (!(wsmt->protection_flags & ACPI_WSMT_FIXED_COMM_BUFFERS) + || !(wsmt->protection_flags + & ACPI_WSMT_COMM_BUFFER_NESTED_PTR_PROTECTION)) + return 0; + + /* Scan for EPS (entry point structure) */ + for (addr = (u8 *)__va(0xf0000); + addr < (u8 *)__va(0x100000 - sizeof(struct smm_eps_table)) && !eps; + addr += 1) + eps = check_eps_table(addr); + + if (!eps) { + dev_dbg(&dcdbas_pdev->dev, "found WSMT, but no EPS found\n"); + return -ENODEV; + } + + /* + * Get physical address of buffer and map to virtual address. + * Table gives size in 4K pages, regardless of actual system page size. + */ + if (eps->smm_comm_buff_addr + 8 > U32_MAX) { + dev_warn(&dcdbas_pdev->dev, "found WSMT, but EPS buffer address is above 4GB\n"); + return -EINVAL; + } + eps_buffer = (u8 *)memremap(eps->smm_comm_buff_addr, + eps->num_of_4k_pages * 4096, MEMREMAP_WB); + if (!eps_buffer) { + dev_warn(&dcdbas_pdev->dev, "found WSMT, but failed to map EPS buffer\n"); + return -ENOMEM; + } + + /* First 8 bytes of buffer is for semaphore */ + smi_data_buf_phys_addr = (u32) eps->smm_comm_buff_addr + 8; + smi_data_buf = eps_buffer + 8; + smi_data_buf_size = (unsigned long) min(eps->num_of_4k_pages * 4096 - 8, + (u64) ULONG_MAX); + max_smi_data_buf_size = smi_data_buf_size; + wsmt_enabled = true; + dev_info(&dcdbas_pdev->dev, + "WSMT found, using firmware-provided SMI buffer.\n"); + return 1; +} + /** * dcdbas_reboot_notify: handle reboot notification for host control */ @@ -548,6 +633,11 @@ static int dcdbas_probe(struct platform_device *dev) dcdbas_pdev = dev; + /* Check if ACPI WSMT table specifies protected SMI buffer address */ + error = dcdbas_check_wsmt(); + if (error < 0) + return error; + /* * BIOS SMI calls require buffer addresses be in 32-bit address space. * This is done by setting the DMA mask below. @@ -635,6 +725,8 @@ static void __exit dcdbas_exit(void) */ if (dcdbas_pdev) smi_data_buf_free(); + if (eps_buffer) + memunmap(eps_buffer); platform_device_unregister(dcdbas_pdev_reg); platform_driver_unregister(&dcdbas_driver); } diff --git a/drivers/firmware/dcdbas.h b/drivers/firmware/dcdbas.h index ca3cb0a54ab6..7ea5b3e070b9 100644 --- a/drivers/firmware/dcdbas.h +++ b/drivers/firmware/dcdbas.h @@ -54,6 +54,8 @@ #define SMI_CMD_MAGIC (0x534D4931) +#define SMM_EPS_SIG "$SCB" + #define DCDBAS_DEV_ATTR_RW(_name) \ DEVICE_ATTR(_name,0600,_name##_show,_name##_store); @@ -103,5 +105,14 @@ struct apm_cmd { int dcdbas_smi_request(struct smi_cmd *smi_cmd); +struct smm_eps_table { + char smm_comm_buff_anchor[4]; + u8 length; + u8 checksum; + u8 version; + u64 smm_comm_buff_addr; + u64 num_of_4k_pages; +} __packed; + #endif /* _DCDBAS_H_ */