Received-SPF: pass (google.com: domain of linux-crypto-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Rijo Thomas <Rijo-john.Thomas@amd.com>
To:     Tom Lendacky <thomas.lendacky@amd.com>,
        John Allen <john.allen@amd.com>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        "David S . Miller" <davem@davemloft.net>,
        linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org
Cc:     Rijo Thomas <Rijo-john.Thomas@amd.com>,
        Mythri Pandeshwara krishna <mythri.pandeshwarakrishna@amd.com>,
        Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>,
        Jens Wiklander <jens.wiklander@linaro.org>,
        Ard Biesheuvel <ard.biesheuvel@linaro.org>
Subject: [PATCH 1/3] crypto: ccp - reduce tee command status polling interval from 5ms to 1ms
Date:   Tue,  9 Mar 2021 13:41:11 +0530
Message-Id: <5cc883bc9bf3ed88056f87ecae1a4e28a52adfe8.1615276206.git.Rijo-john.Thomas@amd.com>
In-Reply-To: <cover.1615276206.git.Rijo-john.Thomas@amd.com>
References: <cover.1615276206.git.Rijo-john.Thomas@amd.com>
Content-Type: text/plain
MIME-Version: 1.0
X-MS-Exchange-MessageSentRepresentingType: 1
Received: from andbang6.amd.com (165.204.156.251) by MA1PR0101CA0068.INDPRD01.PROD.OUTLOOK.COM (2603:1096:a00:20::30) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3912.17 via Frontend Transport; Tue, 9 Mar 2021 08:11:46 +0000
X-MS-PublicTrafficType: Email
X-MS-Office365-Filtering-HT: Tenant
X-MS-Office365-Filtering-Correlation-Id: 2fe53886-7949-47eb-f5d4-08d8e2d2fd2b
X-MS-TrafficTypeDiagnostic: SA0PR12MB4397:
X-MS-Exchange-Transport-Forked: True
X-Microsoft-Antispam-PRVS: <SA0PR12MB43974917377B2D01F7B39AB4CF929@SA0PR12MB4397.namprd12.prod.outlook.com>
X-MS-Oob-TLC-OOBClassifiers: OLM:5516;
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:SN6PR12MB4719.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(366004)(376002)(346002)(396003)(39860400002)(136003)(66476007)(8936002)(5660300002)(4326008)(66556008)(2616005)(956004)(316002)(54906003)(26005)(2906002)(6666004)(8676002)(110136005)(6486002)(83380400001)(66946007)(36756003)(86362001)(186003)(478600001)(16526019)(52116002)(7696005);DIR:OUT;SFP:1101;
X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?ddR1vlnRUmgkLYEfPIGSu3l6MdjRaXGJmTEBDAjPOhQk4EpqkqnmvdQLIsXv?=
 =?us-ascii?Q?BjFpD6vIZvmduW5JoBujUeh8jtXHThyGRcNAAUVo58tfWBzJTsUaKuO/7Hld?=
 =?us-ascii?Q?B+fkbM2OqPWQPJNXzkT1snQCsY4SxTuk0Wx0EhlQpq1yeuviRGvrA+fpTvhh?=
 =?us-ascii?Q?2QVIk7Xfcje8nz9Uo1Y9qlIUQvxAdKmEs7qEWXvGxojD5QSTI/VG20aYgfC8?=
 =?us-ascii?Q?oqa4k8Oyg0ZBMUN6pC8dxMOJFlYhhQnbYLShmlQjgIWofRdT+pB6yIloajCt?=
 =?us-ascii?Q?OLEmFvGulzUL9d2Y/HOfTxn7YIWxaT9VLydKPujmtKiqdlQpRDN68LmANDjp?=
 =?us-ascii?Q?uP3NKT9jaNbtbLZyqxt0djpVYutjDNB4mc7wb4UTT6LlSi5qqAMUakc3Ne9V?=
 =?us-ascii?Q?mAZ4B932frb0B31/grrkICWuIw/q1wiuai5B6nBRKN/7XcJIE5nGUK8iQKjv?=
 =?us-ascii?Q?1840Iy2zG5sgeM/E5Jmyp+/BAj93DfoOy77slIEsC0TOJnQ7XozjTsT6FIex?=
 =?us-ascii?Q?YifJViT7MW3okicVcROGfyDCyLoxo7Yp5oAaiDAU5/LB4VekmCnSHbnkA5Vn?=
 =?us-ascii?Q?R4wnB90VMJPwSpztCmBsvjx5CWPkN2c8JGr6iKuRFoBnfi6TTQ46Gml2UTz+?=
 =?us-ascii?Q?D5sOAaZ6waeGOnkbiRbztnAiqYcLX+crY7/zmISmcFcwYJsKc/7Ea99XOVoz?=
 =?us-ascii?Q?8b84dVLhqN7tv1ACme6z4qKOZHh8z9J8a40klYcYxJ77OJ2yLg9uOrKxKmYx?=
 =?us-ascii?Q?W9dGST+VVSsf70ZhcM0mNL02VUZsvGqPBiCjn6ITwaEwPwMXW/rLg9BMVxqv?=
 =?us-ascii?Q?9vySJTmLrn6K2no/v/ztTxBiwhDhCnqcpHF6YKnjJx+821Gfs+Dmx0idrOaL?=
 =?us-ascii?Q?B0U/4vN8x1medoDdiONgz79smmiEQZg3duy86kkbOJppCx7yFQHy/j0dcXaZ?=
 =?us-ascii?Q?S3r6dTzb/y6L38wohfyXS0LS29i1BXu4R59LhpSkw+FBi1zjRmFSKDR2yhiV?=
 =?us-ascii?Q?GxSLfHFkghvwd2DVJBYqalNXDbk4Ue7i4XJkEFXY/4/LUUurhdxyvdvT5bfn?=
 =?us-ascii?Q?W+u5IlZujGSRVOMZI6pHt42dpwUwbGZu8xIir9cxosw1HVkUiWxZKWlbK1LZ?=
 =?us-ascii?Q?IKCHmbK/g3YFAJe8Vfo2HfP5Vn+pqN4LwI/s2LnK1EYKurxBxRU9RnmfZgY8?=
 =?us-ascii?Q?ogDNE0r2EkZ4Aj4qIAD4Vp8b+rjD4J191D79EvwfEvh4sRQE1qsFTu87m499?=
 =?us-ascii?Q?6ChOqH0r3DWJAyH5fe8dVntBGN4kDLCyR8HX4QlwfEpWh0nq6/4xIoDL4rZd?=
 =?us-ascii?Q?KMcI8265M5CIT6l6ZodYcIEw?=
X-OriginatorOrg: amd.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 2fe53886-7949-47eb-f5d4-08d8e2d2fd2b
X-MS-Exchange-CrossTenant-AuthSource: SN6PR12MB4719.namprd12.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Mar 2021 08:11:49.5798
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: DgRIndQ+mHjAskdyxqPYGPBRKSue61NVCeyBq2QGkvAG02xbkSUSg00ckcjFZMRYuI2R9hnetVjhXqEWpdnscQ==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB4397
Precedence: bulk
List-ID: <linux-crypto.vger.kernel.org>
X-Mailing-List: linux-crypto@vger.kernel.org

The PSP TEE device driver polls the command status variable every
5ms to check for command completion. Reduce this time to 1ms so that
there is an improvement in driver response time to clients which submit
TEE commands.

Reviewed-by: Devaraj Rangasamy <Devaraj.Rangasamy@amd.com>
Signed-off-by: Rijo Thomas <Rijo-john.Thomas@amd.com>
---
 drivers/crypto/ccp/tee-dev.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/crypto/ccp/tee-dev.c b/drivers/crypto/ccp/tee-dev.c
index 5e697a90ea7f..fe18a92d51ad 100644
--- a/drivers/crypto/ccp/tee-dev.c
+++ b/drivers/crypto/ccp/tee-dev.c
@@ -309,14 +309,14 @@ static int tee_wait_cmd_completion(struct psp_tee_device *tee,
 				   struct tee_ring_cmd *resp,
 				   unsigned int timeout)
 {
-	/* ~5ms sleep per loop => nloop = timeout * 200 */
-	int nloop = timeout * 200;
+	/* ~1ms sleep per loop => nloop = timeout * 1000 */
+	int nloop = timeout * 1000;
 
 	while (--nloop) {
 		if (resp->cmd_state == TEE_CMD_STATE_COMPLETED)
 			return 0;
 
-		usleep_range(5000, 5100);
+		usleep_range(1000, 1100);
 	}
 
 	dev_err(tee->dev, "tee: command 0x%x timed out, disabling PSP\n",
-- 
2.17.1