From patchwork Sat Sep 9 20:16:17 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mukesh Ojha X-Patchwork-Id: 13378370 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 6B5C3EE57CD for ; Sat, 9 Sep 2023 20:21:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240358AbjIIUVt (ORCPT ); Sat, 9 Sep 2023 16:21:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55618 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230089AbjIIUVt (ORCPT ); Sat, 9 Sep 2023 16:21:49 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 486A4CE1; Sat, 9 Sep 2023 13:21:14 -0700 (PDT) Received: from pps.filterd (m0279870.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 389KJ9Tl011062; Sat, 9 Sep 2023 20:19:09 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-type; s=qcppdkim1; bh=TbC0LgVICx7ntFXMFzve49qiK3DqPitLLA1eYCd6sfs=; b=MV1rksJMLDRhJ1t647YOpjUroJagrP5pNFqXlnMrKBKSwBTNSti76oULO4sISEm5RfsU WLS1csdm20mN9RKDtWyaqfW8NUJ44xVj1TEuKcG3aI+K/4AXFXKcXwHYAawQFb3NS6Ql 3IJaksZ1BqPfcMQKgLWA+s5Dd2qt2LR7UDJz/bI2TUw3dFILOXZ/rOlSbYqzlHF8s1Hl VISdQab7bPae/bjmOcAbygFX7Wt0jcHSE/GW/V/d7fVi8xFY2kRVT5hyJTuItUCD5OQZ WwWS3/ykdW2jUKsLwZXLZsFufV0Ex/SToNZ6kWeVJwDBimDmpHh5sA70HlOnADegzaIj ug== Received: from nasanppmta01.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3t0gt18xdm-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 09 Sep 2023 20:19:09 +0000 Received: from nasanex01c.na.qualcomm.com (nasanex01c.na.qualcomm.com [10.45.79.139]) by NASANPPMTA01.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 389KJ8Qp008344 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 9 Sep 2023 20:19:08 GMT Received: from hu-mojha-hyd.qualcomm.com (10.80.80.8) by nasanex01c.na.qualcomm.com (10.45.79.139) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.36; Sat, 9 Sep 2023 13:18:57 -0700 From: Mukesh Ojha To: , , , , , , , , , , , , , , , , , , , , , CC: , , , , , , , , , , Subject: [PATCH v5 16/17] firmware: qcom_scm: Refactor code to support multiple download mode Date: Sun, 10 Sep 2023 01:46:17 +0530 Message-ID: <1694290578-17733-17-git-send-email-quic_mojha@quicinc.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1694290578-17733-1-git-send-email-quic_mojha@quicinc.com> References: <1694290578-17733-1-git-send-email-quic_mojha@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nasanex01c.na.qualcomm.com (10.45.79.139) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: 93kG5iSdQhjyDyETPR2lGeBzK75TYnJE X-Proofpoint-GUID: 93kG5iSdQhjyDyETPR2lGeBzK75TYnJE X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.957,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-09_19,2023-09-05_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 priorityscore=1501 lowpriorityscore=0 mlxlogscore=999 impostorscore=0 suspectscore=0 malwarescore=0 clxscore=1015 mlxscore=0 adultscore=0 phishscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309090187 Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org Currently on Qualcomm SoC, download_mode is enabled if CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT is selected. Refactor the code such that it supports multiple download modes and drop CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT config instead, give interface to set the download mode from module parameter. Signed-off-by: Mukesh Ojha --- drivers/firmware/Kconfig | 11 --------- drivers/firmware/qcom_scm.c | 56 +++++++++++++++++++++++++++++++++++++++------ 2 files changed, 49 insertions(+), 18 deletions(-) diff --git a/drivers/firmware/Kconfig b/drivers/firmware/Kconfig index b59e3041fd62..ff7e9f330559 100644 --- a/drivers/firmware/Kconfig +++ b/drivers/firmware/Kconfig @@ -215,17 +215,6 @@ config MTK_ADSP_IPC config QCOM_SCM tristate -config QCOM_SCM_DOWNLOAD_MODE_DEFAULT - bool "Qualcomm download mode enabled by default" - depends on QCOM_SCM - help - A device with "download mode" enabled will upon an unexpected - warm-restart enter a special debug mode that allows the user to - "download" memory content over USB for offline postmortem analysis. - The feature can be enabled/disabled on the kernel command line. - - Say Y here to enable "download mode" by default. - config SYSFB bool select BOOT_VESA_SUPPORT diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c index eda92f713019..689bf882cb69 100644 --- a/drivers/firmware/qcom_scm.c +++ b/drivers/firmware/qcom_scm.c @@ -20,13 +20,13 @@ #include #include #include +#include #include #include #include "qcom_scm.h" -static bool download_mode = IS_ENABLED(CONFIG_QCOM_SCM_DOWNLOAD_MODE_DEFAULT); -module_param(download_mode, bool, 0); +static u32 download_mode; #define SCM_HAS_CORE_CLK BIT(0) #define SCM_HAS_IFACE_CLK BIT(1) @@ -83,6 +83,11 @@ static const char * const qcom_scm_convention_names[] = { [SMC_CONVENTION_LEGACY] = "smc legacy", }; +static const char * const download_mode_name[] = { + [QCOM_DLOAD_NODUMP] = "off", + [QCOM_DLOAD_FULLDUMP] = "full", +}; + static struct qcom_scm *__scm; static DEFINE_SPINLOCK(lock); @@ -448,9 +453,10 @@ static int __qcom_scm_set_dload_mode(struct device *dev, bool enable) return qcom_scm_call_atomic(__scm->dev, &desc, NULL); } -static void qcom_scm_set_download_mode(bool enable) +static void qcom_scm_set_download_mode(u32 download_mode) { - u32 val = enable ? QCOM_DLOAD_FULLDUMP : QCOM_DLOAD_NODUMP; + bool enable = !!download_mode; + u32 val = download_mode; bool avail; int ret = 0; @@ -1430,6 +1436,42 @@ static irqreturn_t qcom_scm_irq_handler(int irq, void *data) return IRQ_HANDLED; } +static int get_download_mode(char *buffer, const struct kernel_param *kp) +{ + if (download_mode >= ARRAY_SIZE(download_mode_name)) + return sysfs_emit(buffer, "unknown mode\n"); + + return sysfs_emit(buffer, "%s\n", download_mode_name[download_mode]); +} + +static int set_download_mode(const char *val, const struct kernel_param *kp) +{ + u32 old = download_mode; + int ret; + + ret = sysfs_match_string(download_mode_name, val); + if (ret < 0) { + download_mode = old; + pr_err("qcom_scm: unknown download mode: %s\n", val); + return -EINVAL; + } + + download_mode = ret; + if (__scm) + qcom_scm_set_download_mode(download_mode); + + return 0; +} + +static const struct kernel_param_ops download_mode_param_ops = { + .get = get_download_mode, + .set = set_download_mode, +}; + +module_param_cb(download_mode, &download_mode_param_ops, NULL, 0644); +MODULE_PARM_DESC(download_mode, + "download mode: off/full are acceptable values"); + static int qcom_scm_probe(struct platform_device *pdev) { struct qcom_scm *scm; @@ -1523,12 +1565,12 @@ static int qcom_scm_probe(struct platform_device *pdev) __get_convention(); /* - * If requested enable "download mode", from this point on warmboot + * If "download mode" is requested, from this point on warmboot * will cause the boot stages to enter download mode, unless * disabled below by a clean shutdown/reboot. */ if (download_mode) - qcom_scm_set_download_mode(true); + qcom_scm_set_download_mode(download_mode); return 0; } @@ -1536,7 +1578,7 @@ static int qcom_scm_probe(struct platform_device *pdev) static void qcom_scm_shutdown(struct platform_device *pdev) { /* Clean shutdown, disable download mode to allow normal restart */ - qcom_scm_set_download_mode(false); + qcom_scm_set_download_mode(QCOM_DLOAD_NODUMP); } static const struct of_device_id qcom_scm_dt_match[] = {