aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/sifiveu/patches-5.15/0006-riscv-sbi-srst-support.patch
blob: 409001bcfa8c6ca4c8a016e24ad01a14c339ce97 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=S+R5=LD=lists.infradead.org=linux-riscv-bounces+linux-riscv=archiver.kernel.org@kernel.org>
X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on
	aws-us-west-2-korg-lkml-1.web.codeaurora.org
X-Spam-Level: 
X-Spam-Status: No, score=-21.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH,
	DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,
	INCLUDES_PATCH,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,MSGID_FROM_MTA_HEADER,
	SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable
	autolearn_force=no version=3.4.0
Received: from mail.kernel.org (mail.kernel.org [198.145.29.99])
	by smtp.lore.kernel.org (Postfix) with ESMTP id 9A34CC48BCD
	for <linux-riscv@archiver.kernel.org>; Wed,  9 Jun 2021 12:50:08 +0000 (UTC)
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 mail.kernel.org (Postfix) with ESMTPS id 69795611C9
	for <linux-riscv@archiver.kernel.org>; Wed,  9 Jun 2021 12:50:08 +0000 (UTC)
DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 69795611C9
Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=wdc.com
Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org
DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed;
	d=lists.infradead.org; s=bombadil.20210309; h=Sender:
	Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post:
	List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:
	Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:
	Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:
	List-Owner; bh=64gRxQ9bX8C6wjLq0KuJ2lv98bQdXijt0LPnNpch3NU=; b=rgeSpoSWQ+Nca2
	9PLsgI7dOYVdTu48CyVJStiizsvIvVFN2rBAgELHF2nRCCtoSiPMxgcpCKtDcm7sh9lC8AblCoBjN
	LXiPRHVYJAcRNiWiQ0qOTqHdTbezFdzSjNOs6drbaiI4B8AZtychw1hP+ubsb5czAaz6510OEVct/
	h5M4Tlljcn/WIyulBd/tnuUOZPT0XL6rb2+TvRQvjXDBFHN+bWqP8OjXKnE1FTvy5MF8OTlUgI6wr
	3f4t/eS/PPbtXRD5raJzEwEQLJ6XY6NJABs40tKpWZNuUaqTfmonNdbP9y1htWhByhsAk+fw5WK/C
	/KocvM6IzPmqGIBWcTdQ==;
Received: from localhost ([::1] helo=bombadil.infradead.org)
	by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux))
	id 1lqxeS-00Do8i-Hj; Wed, 09 Jun 2021 12:49:44 +0000
Received: from esa4.hgst.iphmx.com ([216.71.154.42])
 by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux))
 id 1lqx5h-00DbCQ-K0
 for linux-riscv@lists.infradead.org; Wed, 09 Jun 2021 12:13:51 +0000
DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple;
 d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com;
 t=1623240829; x=1654776829;
 h=from:to:cc:subject:date:message-id:in-reply-to:
 references:content-transfer-encoding:mime-version;
 bh=s4va/Owvq7MQI8rUsD/e02RmaYfJNzYNcxlXspGRY7g=;
 b=G5GD9eN+rv669E7jyRnRAt0jw83CxhIrSiDIjXuPmhWyMhKeQGD7ACRm
 ii6o0zmOREhGihtwB6X/xpY/2ZvK+cxcHmJXa+Ykyn8QN+/YKFtg3svfj
 eiTN7U/mEozCoGNd1wXu59RQj11Xz60DN/qEUlYFaL6SjukUgifFVgbvG
 uUj8AM8+xf1jKHi3Q/6nVPpJX8uiW/NPFHrwI8hxUwYr9viQwxXvc7FNr
 fR8bH2c/HiGacGYEHosgP0WT//d9Huqn4JNINvjidK4ZSJ74cXlr8KwMG
 8snmfx4UjEWMhK1lCYalJEU7nxXFfih/6DMuFRorETpWQ+424BAKUJdDH Q==;
IronPort-SDR: pYhRsIZkhfmi45K4HfnZj39kxfUGpxs1e+q+Wh8kDE+ySh35HkJaaUcpP04mb7VeIVtPRx/h6Q
 imv6sn8fYo/V8ezHAq4jpd1QadqInKi1ubLnCE3Zy7GnhVBepoV6FbI14Y01V+5QIUwYdFNcGG
 RsxDOTQyU5AljH0Rc6WkrpdVf5jsrXXMddmlDdi6QsfKGy7MwQ/NYojNIqyLhRSgu5w2uTIE7X
 atSbjb8j2a+EJUY0WgYTGfNHKCdQLAhjcsWZgU7Iu0vSaBU6A7seCkqun24dvF/zYuzEj7wedD
 TvE=
X-IronPort-AV: E=Sophos;i="5.83,260,1616428800"; d="scan'208";a="170575129"
Received: from mail-dm6nam12lp2169.outbound.protection.outlook.com (HELO
 NAM12-DM6-obe.outbound.protection.outlook.com) ([104.47.59.169])
 by ob1.hgst.iphmx.com with ESMTP; 09 Jun 2021 20:13:48 +0800
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none;
 b=hrlr4Qi66FmbQW45zI7QeA9nEYSvxO+tR++vUyFHxjRqnr6WtjKgHM8hPpp8oHXaK82U0+KQUc2+WjLbe8LihexXFQs5zRwBDwuArmkKt85cL3utD3OBzTkr4A9ZhRS5mzztnn9kvTFNplPjSydXPetJQIZ9WKmihJrdeaGQ+zQ//6TdDWVpLyBbqiBVUbUwlKQbpbbfHvzQCHYQbIiUcGn4vaSXYp2Xp1Z5yYVtrfDK+TemKG/8fKQoJjg/tdmDtQ97Cgw7nX6Oc9kdmoTIxFilMy4XjPciPcNOPdLmboGCt6+TMBeftLc1VFNnr7PwuxOogv4I7eJ/P9UaK57k5A==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; 
 s=arcselector9901;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
 bh=Ibi36Vj2s7bu56DZaU1uSl4xNA3OB2FHlI/rBKn+8xo=;
 b=CE3o+0GFLPMQuw0AK1IRf/vX00diXsjayn0MmpS7ntSVXgxXIAPT9aDtk7x0NovJBTk2LHI5Mtxvz6SwVnJzUqZmNsXUktEj5Iwdd8EPIIxgCOjugo/6WC0FqaFKNvJB4hQ0tjFxv+J5DexSJ8+mPx6Ucr4DwtUXrCWzOeXyF5YK68mU5FgttbyutW3CGsGkPgaPAdOxXOgJqyYu8X25unmzG12Jq2xC4oVKsbA+RfDiaMKm97q2Bhy+LcgJNS6/ktlFKSOVu1HQ0POYgba3mtldN3vg73wLbxrfsdoe4261aJpkM05GJFDzdTNp4t3rEGhNuLR1+8OmKfLlPeSU9w==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass
 smtp.mailfrom=wdc.com; dmarc=pass action=none header.from=wdc.com; dkim=pass
 header.d=wdc.com; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=sharedspace.onmicrosoft.com; s=selector2-sharedspace-onmicrosoft-com;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
 bh=Ibi36Vj2s7bu56DZaU1uSl4xNA3OB2FHlI/rBKn+8xo=;
 b=Z76YsVxTHK6/ta19C5vwaBPYmtDa2GIM/ml4myQZfIaHFNzXPzZ+PFcYy/Xf1Ixd0GZHcuSZQYgs/SPHWATh+rOWBAislGv1zmSAG/g0tiDckB8WaCwh1e3qGW4ZmUTmAU7dxB0vn0pRSLTnc1hdCUZ73buM78qo9qwsQZv41d0=
Authentication-Results: dabbelt.com; dkim=none (message not signed)
 header.d=none;dabbelt.com; dmarc=none action=none header.from=wdc.com;
Received: from CO6PR04MB7812.namprd04.prod.outlook.com (2603:10b6:303:138::6)
 by CO6PR04MB7794.namprd04.prod.outlook.com (2603:10b6:303:13f::7)
 with Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4219.21; Wed, 9 Jun
 2021 12:13:47 +0000
Received: from CO6PR04MB7812.namprd04.prod.outlook.com
 ([fe80::a153:b7f8:c87f:89f8]) by CO6PR04MB7812.namprd04.prod.outlook.com
 ([fe80::a153:b7f8:c87f:89f8%9]) with mapi id 15.20.4219.021; Wed, 9 Jun 2021
 12:13:47 +0000
From: Anup Patel <anup.patel@wdc.com>
To: Palmer Dabbelt <palmer@dabbelt.com>,
 Palmer Dabbelt <palmerdabbelt@google.com>,
 Paul Walmsley <paul.walmsley@sifive.com>, Albert Ou <aou@eecs.berkeley.edu>
Cc: Atish Patra <atish.patra@wdc.com>,
 Alistair Francis <Alistair.Francis@wdc.com>,
 Anup Patel <anup@brainfault.org>, linux-riscv@lists.infradead.org,
 linux-kernel@vger.kernel.org, Anup Patel <anup.patel@wdc.com>
Subject: [PATCH v7 1/1] RISC-V: Use SBI SRST extension when available
Date: Wed,  9 Jun 2021 17:43:22 +0530
Message-Id: <20210609121322.3058-2-anup.patel@wdc.com>
X-Mailer: git-send-email 2.25.1
In-Reply-To: <20210609121322.3058-1-anup.patel@wdc.com>
References: <20210609121322.3058-1-anup.patel@wdc.com>
X-Originating-IP: [122.172.176.125]
X-ClientProxiedBy: MA1PR0101CA0036.INDPRD01.PROD.OUTLOOK.COM
 (2603:1096:a00:22::22) To CO6PR04MB7812.namprd04.prod.outlook.com
 (2603:10b6:303:138::6)
MIME-Version: 1.0
X-MS-Exchange-MessageSentRepresentingType: 1
Received: from wdc.com (122.172.176.125) by
 MA1PR0101CA0036.INDPRD01.PROD.OUTLOOK.COM (2603:1096:a00:22::22) with
 Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4219.21 via Frontend
 Transport; Wed, 9 Jun 2021 12:13:44 +0000
X-MS-PublicTrafficType: Email
X-MS-Office365-Filtering-Correlation-Id: 17406ef0-e8d7-4dc3-eee9-08d92b40085b
X-MS-TrafficTypeDiagnostic: CO6PR04MB7794:
X-MS-Exchange-Transport-Forked: True
X-Microsoft-Antispam-PRVS: <CO6PR04MB77945CDDD1538EFCA060925B8D369@CO6PR04MB7794.namprd04.prod.outlook.com>
WDCIPOUTBOUND: EOP-TRUE
X-MS-Oob-TLC-OOBClassifiers: OLM:2887;
X-MS-Exchange-SenderADCheck: 1
X-Microsoft-Antispam: BCL:0;
X-Microsoft-Antispam-Message-Info: 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
X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:;
 IPV:NLI; SFV:NSPM; H:CO6PR04MB7812.namprd04.prod.outlook.com; PTR:; CAT:NONE;
 SFS:(4636009)(396003)(39860400002)(136003)(346002)(366004)(376002)(8676002)(316002)(55236004)(38100700002)(38350700002)(110136005)(86362001)(54906003)(4326008)(956004)(966005)(478600001)(26005)(186003)(55016002)(8936002)(2616005)(7696005)(52116002)(16526019)(5660300002)(8886007)(6666004)(1076003)(66476007)(66556008)(36756003)(66946007)(83380400001)(2906002)(44832011);
 DIR:OUT; SFP:1102; 
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?2kfiFAcyFkAMcwkoCUqJGxdVnwsuTm5WWTXA4Pq0ZNAjWsfYI4MNugTA9f8C?=
 =?us-ascii?Q?WaQrYEizTkvIlgRDqeKVRS0vaMaeU9XaSzO6UAJMnd0jY3BzkJgKUU9xj1aU?=
 =?us-ascii?Q?vmwXKxCS+vZ2VKgLifaU1JCeemiJqV9aW+6AJEycq722bz9yXmcaJsaHWtX3?=
 =?us-ascii?Q?4sSoLeVPvfzwzDZEEoGsZZi1G7inY2imGEgY/r3m5/qYvavJQ3An4e4sjEqZ?=
 =?us-ascii?Q?Z4a4FAd/6c3X8cjmNwGvgWoAIM5WaJYFQe30MQ79alCUfZyiKB4tR0+5OGFd?=
 =?us-ascii?Q?P/rQ169Z644JNKKcEabikpL7qZZJ6OMPTS7XR9x/7GzWOJ7soV3/3I2tfCdi?=
 =?us-ascii?Q?xVsOK1DRF4y6gi5udvnb+Uu1U5wC1NlT0U/+TrnTSeY/IuLmMgFUysw+fQ+D?=
 =?us-ascii?Q?DIVN44TKrMoEZKx9SKcx4jYpUGYvaCH4sVOAx3zWQC0Oz1Nz3/a/isywpQW9?=
 =?us-ascii?Q?1I1kl/2N97K0EoWIPf6qPjyLVWXg1dOHfk6SjNW64JIIPUNnM3h7k2igDX3o?=
 =?us-ascii?Q?d7lWyFfzoWhNC7opS71uzta+ti8aHxo+xzvYvf2wLb+fdyEP9t+oQVrEQYIW?=
 =?us-ascii?Q?rAUKPqjEfAZOYBB28SaabfVt/QF6hFfV/0yJ/JV/Ie8ivC1t6iO+QZQscV7K?=
 =?us-ascii?Q?d4Pg+xVSE+m+LsgNwO36cTTe6hSLBPnWU1NMOW2cxTRKGm0Lwd2HyjyKTBMD?=
 =?us-ascii?Q?BcnKo9GXAVgOAGCG5cwEBN76q6sXxbWy0pjni3O2bLYBg4CIYCB/JNzOIfE0?=
 =?us-ascii?Q?Toz6Qwc4aw5NxRLqz9IygGT6ZunRVUWUsgJrIt5U20elX+lRmtX1cqrQNTON?=
 =?us-ascii?Q?ZHzuAI587pB0zK4EiS25hc9C8RtwjlY67heuMsYZDww5TU+NV3+0WN1/NrCX?=
 =?us-ascii?Q?3kB7O188tvm1sWVhCaC6hk9s19nKGRgMS5OHXTMxhmyw1Dn/zorMYff3r9ZE?=
 =?us-ascii?Q?sNiBI7fwru/Jsxt2/jNCpFaEYUa9JkrdSse76BXo/UxLALnxO3bzpym3Dq+T?=
 =?us-ascii?Q?s4uEA8UncKM0e+Mhp9hW1c3DR61Qjj8wb+LV3XB0qYK/1rHs8IDdJ97tw1fp?=
 =?us-ascii?Q?Ux9SlgS9YE2bEp6wxcX6TpA5DoYjqdlK50/4/DZ3YTXWlPTaQbt/j36TbEgZ?=
 =?us-ascii?Q?hhIV08WX7EDjBz1QrFRppEtBghOJikHLdvPo6GnZkHNQ9cxaa8Jrk0iypK4d?=
 =?us-ascii?Q?bMj47kiugWCGY+ZW2ioGV1GgH1aZEvAukQgTiAAiyGU83td11Q5Pv2N5ytvk?=
 =?us-ascii?Q?i+Ux/DUoeU4VyqYnb69asjdyKI5RzIxQPdQAQ7x/TBlyPp/Yj2/v31b6lCYT?=
 =?us-ascii?Q?b1iYdeIKK+6I6A+e/EUnPOKC?=
X-OriginatorOrg: wdc.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 17406ef0-e8d7-4dc3-eee9-08d92b40085b
X-MS-Exchange-CrossTenant-AuthSource: CO6PR04MB7812.namprd04.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Jun 2021 12:13:47.1304 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: b61c8803-16f3-4c35-9b17-6f65f441df86
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: rHld9c5jovIZF30ZL04ehEJ81O0isWetsUM3vlp/0cN1LoJ5z8guKzUTANDGVGM0Eua+2cZ1jQGTC49NwWH4hA==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CO6PR04MB7794
X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 
X-CRM114-CacheID: sfid-20210609_051349_766689_30430D67 
X-CRM114-Status: GOOD (  15.29  )
X-BeenThere: linux-riscv@lists.infradead.org
X-Mailman-Version: 2.1.34
Precedence: list
List-Id: <linux-riscv.lists.infradead.org>
List-Unsubscribe: <http://lists.infradead.org/mailman/options/linux-riscv>,
 <mailto:linux-riscv-request@lists.infradead.org?subject=unsubscribe>
List-Archive: <http://lists.infradead.org/pipermail/linux-riscv/>
List-Post: <mailto:linux-riscv@lists.infradead.org>
List-Help: <mailto:linux-riscv-request@lists.infradead.org?subject=help>
List-Subscribe: <http://lists.infradead.org/mailman/listinfo/linux-riscv>,
 <mailto:linux-riscv-request@lists.infradead.org?subject=subscribe>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: "linux-riscv" <linux-riscv-bounces@lists.infradead.org>
Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org

The SBI SRST extension provides a standard way to poweroff and
reboot the system irrespective to whether Linux RISC-V S-mode
is running natively (HS-mode) or inside Guest/VM (VS-mode).

The SBI SRST extension is available in the SBI v0.3 specification.
(Refer, https://github.com/riscv/riscv-sbi-doc/releases/tag/v0.3.0-rc1)

This patch extends Linux RISC-V SBI implementation to detect
and use SBI SRST extension.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
---
 arch/riscv/include/asm/sbi.h | 24 ++++++++++++++++++++++++
 arch/riscv/kernel/sbi.c      | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+)

--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -27,6 +27,7 @@ enum sbi_ext_id {
 	SBI_EXT_IPI = 0x735049,
 	SBI_EXT_RFENCE = 0x52464E43,
 	SBI_EXT_HSM = 0x48534D,
+	SBI_EXT_SRST = 0x53525354,
 };
 
 enum sbi_ext_base_fid {
@@ -70,6 +71,21 @@ enum sbi_hsm_hart_status {
 	SBI_HSM_HART_STATUS_STOP_PENDING,
 };
 
+enum sbi_ext_srst_fid {
+	SBI_EXT_SRST_RESET = 0,
+};
+
+enum sbi_srst_reset_type {
+	SBI_SRST_RESET_TYPE_SHUTDOWN = 0,
+	SBI_SRST_RESET_TYPE_COLD_REBOOT,
+	SBI_SRST_RESET_TYPE_WARM_REBOOT,
+};
+
+enum sbi_srst_reset_reason {
+	SBI_SRST_RESET_REASON_NONE = 0,
+	SBI_SRST_RESET_REASON_SYS_FAILURE,
+};
+
 #define SBI_SPEC_VERSION_DEFAULT	0x1
 #define SBI_SPEC_VERSION_MAJOR_SHIFT	24
 #define SBI_SPEC_VERSION_MAJOR_MASK	0x7f
@@ -148,6 +164,14 @@ static inline unsigned long sbi_minor_ve
 	return sbi_spec_version & SBI_SPEC_VERSION_MINOR_MASK;
 }
 
+/* Make SBI version */
+static inline unsigned long sbi_mk_version(unsigned long major,
+					    unsigned long minor)
+{
+	return ((major & SBI_SPEC_VERSION_MAJOR_MASK) <<
+		SBI_SPEC_VERSION_MAJOR_SHIFT) | minor;
+}
+
 int sbi_err_map_linux_errno(int err);
 #else /* CONFIG_RISCV_SBI */
 static inline int sbi_remote_fence_i(const unsigned long *hart_mask) { return -1; }
--- a/arch/riscv/kernel/sbi.c
+++ b/arch/riscv/kernel/sbi.c
@@ -7,6 +7,7 @@
 
 #include <linux/init.h>
 #include <linux/pm.h>
+#include <linux/reboot.h>
 #include <asm/sbi.h>
 #include <asm/smp.h>
 
@@ -501,6 +502,32 @@ int sbi_remote_hfence_vvma_asid(const un
 }
 EXPORT_SYMBOL(sbi_remote_hfence_vvma_asid);
 
+static void sbi_srst_reset(unsigned long type, unsigned long reason)
+{
+	sbi_ecall(SBI_EXT_SRST, SBI_EXT_SRST_RESET, type, reason,
+		  0, 0, 0, 0);
+	pr_warn("%s: type=0x%lx reason=0x%lx failed\n",
+		__func__, type, reason);
+}
+
+static int sbi_srst_reboot(struct notifier_block *this,
+			   unsigned long mode, void *cmd)
+{
+	sbi_srst_reset((mode == REBOOT_WARM || mode == REBOOT_SOFT) ?
+		       SBI_SRST_RESET_TYPE_WARM_REBOOT :
+		       SBI_SRST_RESET_TYPE_COLD_REBOOT,
+		       SBI_SRST_RESET_REASON_NONE);
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block sbi_srst_reboot_nb;
+
+static void sbi_srst_power_off(void)
+{
+	sbi_srst_reset(SBI_SRST_RESET_TYPE_SHUTDOWN,
+		       SBI_SRST_RESET_REASON_NONE);
+}
+
 /**
  * sbi_probe_extension() - Check if an SBI extension ID is supported or not.
  * @extid: The extension ID to be probed.
@@ -608,6 +635,14 @@ void __init sbi_init(void)
 		} else {
 			__sbi_rfence	= __sbi_rfence_v01;
 		}
+		if ((sbi_spec_version >= sbi_mk_version(0, 3)) &&
+		    (sbi_probe_extension(SBI_EXT_SRST) > 0)) {
+			pr_info("SBI SRST extension detected\n");
+			pm_power_off = sbi_srst_power_off;
+			sbi_srst_reboot_nb.notifier_call = sbi_srst_reboot;
+			sbi_srst_reboot_nb.priority = 192;
+			register_restart_handler(&sbi_srst_reboot_nb);
+		}
 	} else {
 		__sbi_set_timer = __sbi_set_timer_v01;
 		__sbi_send_ipi	= __sbi_send_ipi_v01;