From patchwork Mon Oct 28 18:44:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elliot Berman X-Patchwork-Id: 13853865 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D66F4D3E2A0 for ; Mon, 28 Oct 2024 18:51:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:CC:To:In-Reply-To:References :Message-ID:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=QezESXxHqBez0fhuBmP1of7VV/80rnDoCk4pnfhP+14=; b=Outw8GaT+YRNENtwTVFV8PYEm8 JWvL0K36cmrKIjw4LogtcbnnQxGeaLCsnGXxgCTm63NLmTGRi27VmIlG3Z65sIFICj+1y5SQI3NCk 4mdZmbaFDwr91N+k/iSx1TNvUYftkESS1PgDzU+uYiAVviEl6V//3FTm5mQBm1MM1FnAEfo2UeiIC a/jm9Rj5EM7hPDyfKS3tSa0wTBu9IFwAO1AXh+0orA0wM1QgNWezYf4YSjhnsrlUcGjemmA1eI94d jaR16T/II3DhRtW+sCnyoJDfDKfSmAECHu9gERzipy0Si7o/i1d+Fhq1I/sBdsa943UHYfvkYQfVP h+/1f5ng==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1t5Upv-0000000Btcu-0Z70; Mon, 28 Oct 2024 18:51:31 +0000 Received: from mx0a-0031df01.pphosted.com ([205.220.168.131]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1t5Ujr-0000000BsRt-0FGt for linux-arm-kernel@lists.infradead.org; Mon, 28 Oct 2024 18:45:17 +0000 Received: from pps.filterd (m0279866.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49SAWsTX031602; Mon, 28 Oct 2024 18:45:03 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= QezESXxHqBez0fhuBmP1of7VV/80rnDoCk4pnfhP+14=; b=QmYwtrTCwyrtMWoY 6luxXCp+njCCtwlReb2W/0q41/jEDMCZxoiBC5bHN66huZe4JNif7QXalu2fsmOT wftDsBccfpEFc0u1sVKPfA7vNfcweutOz5jt/FnNkvE8Zi5rJZyngg6fkn+Mccxt smKV2gyZj7whetbo09jEy5z5mRKs+fr937IkqT4cexIhqjOhbA999y5kR0rvladp EtBZwJEoRhrSsHJrYEtJmeQraPBBcd7JmHnEPFpNg+1aC64HALS/2INj/HuXFIlq EXUzAc8sypz8sxfDr6R9SUzgcJP/v2ljJa2Sb/DDsrYJ9DnLXFrYiM41BcoiwQMd t2sxLw== Received: from nasanppmta02.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 42gsq8dyun-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 28 Oct 2024 18:45:03 +0000 (GMT) Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA02.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 49SIj25w027569 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 28 Oct 2024 18:45:02 GMT Received: from hu-eberman-lv.qualcomm.com (10.49.16.6) by nasanex01b.na.qualcomm.com (10.46.141.250) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.9; Mon, 28 Oct 2024 11:45:01 -0700 From: Elliot Berman Date: Mon, 28 Oct 2024 11:44:57 -0700 Subject: [PATCH v7 3/5] firmware: psci: Read and use vendor reset types MIME-Version: 1.0 Message-ID: <20241028-arm-psci-system_reset2-vendor-reboots-v7-3-a4c40b0ebc54@quicinc.com> References: <20241028-arm-psci-system_reset2-vendor-reboots-v7-0-a4c40b0ebc54@quicinc.com> In-Reply-To: <20241028-arm-psci-system_reset2-vendor-reboots-v7-0-a4c40b0ebc54@quicinc.com> To: Bjorn Andersson , Sebastian Reichel , Rob Herring , Conor Dooley , Vinod Koul , Andy Yan , Lorenzo Pieralisi , "Mark Rutland" , Bartosz Golaszewski , Arnd Bergmann , "Olof Johansson" , Catalin Marinas , "Will Deacon" , , "Krzysztof Kozlowski" , Konrad Dybcio , Konrad Dybcio CC: Satya Durga Srinivasu Prabhala , Melody Olvera , Shivendra Pratap , , , , Florian Fainelli , Stephen Boyd , , , Elliot Berman X-Mailer: b4 0.14.1 X-Originating-IP: [10.49.16.6] X-ClientProxiedBy: nalasex01b.na.qualcomm.com (10.47.209.197) To nasanex01b.na.qualcomm.com (10.46.141.250) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: Zz7cm5HOTG31oEA3rQNNnz8V0W4_KbHF X-Proofpoint-ORIG-GUID: Zz7cm5HOTG31oEA3rQNNnz8V0W4_KbHF X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1039,Hydra:6.0.680,FMLib:17.12.60.29 definitions=2024-09-06_09,2024-09-06_01,2024-09-02_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 bulkscore=0 adultscore=0 mlxscore=0 priorityscore=1501 mlxlogscore=999 impostorscore=0 lowpriorityscore=0 malwarescore=0 clxscore=1011 spamscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410280147 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241028_114515_152037_1302D750 X-CRM114-Status: GOOD ( 25.45 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org SoC vendors have different types of resets and are controlled through various registers. For instance, Qualcomm chipsets can reboot to a "download mode" that allows a RAM dump to be collected. Another example is they also support writing a cookie that can be read by bootloader during next boot. PSCI offers a mechanism, SYSTEM_RESET2, for these vendor reset types to be implemented without requiring drivers for every register/cookie. Add support in PSCI to statically map reboot mode commands from userspace to a vendor reset and cookie value using the device tree. A separate initcall is needed to parse the devicetree, instead of using psci_dt_init because mm isn't sufficiently set up to allocate memory. Reboot mode framework is close but doesn't quite fit with the design and requirements for PSCI SYSTEM_RESET2. Some of these issues can be solved but doesn't seem reasonable in sum: 1. reboot mode registers against the reboot_notifier_list, which is too early to call SYSTEM_RESET2. PSCI would need to remember the reset type from the reboot-mode framework callback and use it psci_sys_reset. 2. reboot mode assumes only one cookie/parameter is described in the device tree. SYSTEM_RESET2 uses 2: one for the type and one for cookie. 3. psci cpuidle driver already registers a driver against the arm,psci-1.0 compatible. Refactoring would be needed to have both a cpuidle and reboot-mode driver. Tested-by: Florian Fainelli Signed-off-by: Elliot Berman --- drivers/firmware/psci/psci.c | 104 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 104 insertions(+) diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index 2328ca58bba6..2d7b6efc8743 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -79,6 +79,14 @@ struct psci_0_1_function_ids get_psci_0_1_function_ids(void) static u32 psci_cpu_suspend_feature; static bool psci_system_reset2_supported; +struct psci_reset_param { + const char *mode; + u32 reset_type; + u32 cookie; +}; +static struct psci_reset_param *psci_reset_params; +static size_t num_psci_reset_params; + static inline bool psci_has_ext_power_state(void) { return psci_cpu_suspend_feature & @@ -305,9 +313,38 @@ static int get_set_conduit_method(const struct device_node *np) return 0; } +static void psci_vendor_system_reset2(unsigned long action, void *data) +{ + const char *cmd = data; + unsigned long ret; + size_t i; + + for (i = 0; i < num_psci_reset_params; i++) { + if (!strcmp(psci_reset_params[i].mode, cmd)) { + ret = invoke_psci_fn(PSCI_FN_NATIVE(1_1, SYSTEM_RESET2), + psci_reset_params[i].reset_type, + psci_reset_params[i].cookie, 0); + /* + * if vendor reset fails, log it and fall back to + * architecture reset types + */ + pr_err("failed to perform reset \"%s\": %ld\n", cmd, + (long)ret); + } + } +} + static int psci_sys_reset(struct notifier_block *nb, unsigned long action, void *data) { + /* + * try to do the vendor system_reset2 + * If the reset fails or there wasn't a match on the command, + * fall back to architectural resets + */ + if (data && num_psci_reset_params) + psci_vendor_system_reset2(action, data); + if ((reboot_mode == REBOOT_WARM || reboot_mode == REBOOT_SOFT) && psci_system_reset2_supported) { /* @@ -750,6 +787,73 @@ static const struct of_device_id psci_of_match[] __initconst = { {}, }; +#define REBOOT_PREFIX "mode-" + +static int __init psci_init_system_reset2_modes(void) +{ + const size_t len = strlen(REBOOT_PREFIX); + struct psci_reset_param *param; + struct device_node *psci_np __free(device_node) = NULL; + struct device_node *np __free(device_node) = NULL; + struct property *prop; + size_t count = 0; + u32 magic[2]; + int num; + + if (!psci_system_reset2_supported) + return 0; + + psci_np = of_find_matching_node(NULL, psci_of_match); + if (!psci_np) + return 0; + + np = of_find_node_by_name(psci_np, "reset-types"); + if (!np) + return 0; + + for_each_property_of_node(np, prop) { + if (strncmp(prop->name, REBOOT_PREFIX, len)) + continue; + num = of_property_count_u32_elems(np, prop->name); + if (num != 1 && num != 2) + continue; + + count++; + } + + param = psci_reset_params = + kcalloc(count, sizeof(*psci_reset_params), GFP_KERNEL); + if (!psci_reset_params) + return -ENOMEM; + + for_each_property_of_node(np, prop) { + if (strncmp(prop->name, REBOOT_PREFIX, len)) + continue; + + param->mode = kstrdup_const(prop->name + len, GFP_KERNEL); + if (!param->mode) + continue; + + num = of_property_read_variable_u32_array(np, prop->name, magic, + 1, ARRAY_SIZE(magic)); + if (num < 0) { + pr_warn("Failed to parse vendor reboot mode %s\n", + param->mode); + kfree_const(param->mode); + continue; + } + + /* Force reset type to be in vendor space */ + param->reset_type = PSCI_1_1_RESET_TYPE_VENDOR_START | magic[0]; + param->cookie = num > 1 ? magic[1] : 0; + param++; + num_psci_reset_params++; + } + + return 0; +} +arch_initcall(psci_init_system_reset2_modes); + int __init psci_dt_init(void) { struct device_node *np;