From nobody Thu Dec 18 07:15:42 2025 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 DAF96C61D92 for ; Tue, 21 Nov 2023 11:25:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232073AbjKULZ3 (ORCPT ); Tue, 21 Nov 2023 06:25:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45108 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233942AbjKULZQ (ORCPT ); Tue, 21 Nov 2023 06:25:16 -0500 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35F7798; Tue, 21 Nov 2023 03:25:12 -0800 (PST) Received: from pps.filterd (m0279868.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3ALA8UYs008889; Tue, 21 Nov 2023 11:25:10 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=7IOTVfCbvSUPGBQV9KfSBf5KQxnkGEB+stp/H1lLn8g=; b=XKxEZzNZxOKnWAYiX45I/4CClvqX2dj2sLe6Hxrf11R5AQaNcvinw48MaCgU6lR4Q8R5 m/mL8c6zh9MUn6Iva9zW6bmY9e8/hzHGoF9IOavueQKJYheT35Qhrx7z7Ob2WavN0vGu Sn65uZyj92XXhVwcq8NwnRtUqyLPbF8nX365PRmqS+4fya74+m4NgvBsC5oEM9VPelsi TpplG1KD15jjkTqA12lCVUJz/jkDhYp7JuOoy/C15hMtT86AAQHd8Nnh5eeIUEikZyd0 hV21o2x3QdufSewd0dlcQZUTEKvfclyH+cm3veGWyTZhj6cWCTJuIuM4WucYpb9EDC+6 9w== Received: from nalasppmta05.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3ugr85rk6c-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Nov 2023 11:25:10 +0000 Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA05.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 3ALBP8vY015770 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 21 Nov 2023 11:25:08 GMT Received: from hu-ekangupt-hyd.qualcomm.com (10.80.80.8) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.40; Tue, 21 Nov 2023 03:25:06 -0800 From: Ekansh Gupta To: , CC: , Subject: [PATCH v3 2/5] misc: fastrpc: Add polling mode support for fastRPC driver Date: Tue, 21 Nov 2023 16:54:51 +0530 Message-ID: <20231121112454.12764-3-quic_ekangupt@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20231121112454.12764-1-quic_ekangupt@quicinc.com> References: <20231121112454.12764-1-quic_ekangupt@quicinc.com> MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01b.na.qualcomm.com (10.47.209.197) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: T_642ZLzh914_oc7AtN4QFJVy4wYpXCx X-Proofpoint-ORIG-GUID: T_642ZLzh914_oc7AtN4QFJVy4wYpXCx X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-21_04,2023-11-21_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 impostorscore=0 phishscore=0 suspectscore=0 adultscore=0 malwarescore=0 bulkscore=0 priorityscore=1501 lowpriorityscore=0 mlxscore=0 clxscore=1015 mlxlogscore=948 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311210088 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" For any remote call to DSP, after sending an invocation message, fastRPC driver waits for glink response and during this time the CPU can go into low power modes. Adding a polling mode support with which fastRPC driver will poll continuously on a memory after sending a message to remote subsystem which will eliminate CPU wakeup and scheduling latencies and reduce fastRPC overhead. With this change, DSP always sends a glink response which will get ignored if polling mode didn't time out. Signed-off-by: Ekansh Gupta --- Changes in v3: - Rebase the patch to latest kernel version drivers/misc/fastrpc.c | 49 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index 6b6ac3e3328d..4f8ecfcdf89f 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -109,6 +109,8 @@ #define FASTRPC_RSP_VERSION2 2 /* Early wake up poll completion number received from remoteproc */ #define FASTRPC_EARLY_WAKEUP_POLL (0xabbccdde) +/* Poll response number from remote processor for call completion */ +#define FASTRPC_POLL_RESPONSE (0xdecaf) /* timeout in us for polling until memory barrier */ #define FASTRPC_POLL_TIME_MEM_UPDATE (500) /* timeout in us for busy polling after early response from remoteproc */ @@ -380,10 +382,14 @@ struct fastrpc_user { struct fastrpc_buf *init_mem; =20 u32 profile; + /* Threads poll for specified timeout and fall back to glink wait */ + u32 poll_timeout; int tgid; int pd; bool is_secure_dev; bool sharedcb; + /* If set, threads will poll for DSP response instead of glink wait */ + bool poll_mode; /* Lock for lists */ spinlock_t lock; /* lock for allocations */ @@ -1376,6 +1382,11 @@ static int poll_for_remote_response(struct fastrpc_i= nvoke_ctx *ctx, u32 timeout) /* Remote processor sent early response */ err =3D 0; break; + } else if (*poll =3D=3D FASTRPC_POLL_RESPONSE) { + err =3D 0; + ctx->is_work_done =3D true; + ctx->retval =3D 0; + break; } if (jj =3D=3D FASTRPC_POLL_TIME_MEM_UPDATE) { /* Wait for DSP to finish updating poll memory */ @@ -1451,6 +1462,15 @@ static void fastrpc_wait_for_completion(struct fastr= pc_invoke_ctx *ctx, if (*ptr_interrupted || ctx->is_work_done) return; break; + case POLL_MODE: + err =3D poll_for_remote_response(ctx, ctx->fl->poll_timeout); + + /* If polling timed out, move to normal response state */ + if (err) + ctx->rsp_flags =3D NORMAL_RESPONSE; + else + *ptr_interrupted =3D 0; + break; default: *ptr_interrupted =3D -EBADR; dev_err(ctx->fl->sctx->dev, "unsupported response type:0x%x\n", ctx->rs= p_flags); @@ -2065,6 +2085,32 @@ static int fastrpc_invoke(struct fastrpc_user *fl, c= har __user *argp) return err; } =20 +static int fastrpc_manage_poll_mode(struct fastrpc_user *fl, u32 enable, u= 32 timeout) +{ + const unsigned int MAX_POLL_TIMEOUT_US =3D 10000; + + if ((fl->cctx->domain_id !=3D CDSP_DOMAIN_ID) || (fl->pd !=3D USER_PD)) { + dev_err(&fl->cctx->rpdev->dev, "poll mode only allowed for dynamic CDSP = process\n"); + return -EPERM; + } + if (timeout > MAX_POLL_TIMEOUT_US) { + dev_err(&fl->cctx->rpdev->dev, "poll timeout %u is greater than max allo= wed value %u\n", + timeout, MAX_POLL_TIMEOUT_US); + return -EBADMSG; + } + spin_lock(&fl->lock); + if (enable) { + fl->poll_mode =3D true; + fl->poll_timeout =3D timeout; + } else { + fl->poll_mode =3D false; + fl->poll_timeout =3D 0; + } + spin_unlock(&fl->lock); + dev_info(&fl->cctx->rpdev->dev, "updated poll mode to %d, timeout %u\n", = enable, timeout); + return 0; +} + static int fastrpc_internal_control(struct fastrpc_user *fl, struct fastrpc_internal_control *cp) { @@ -2079,6 +2125,9 @@ static int fastrpc_internal_control(struct fastrpc_us= er *fl, case FASTRPC_CONTROL_SMMU: fl->sharedcb =3D cp->smmu.sharedcb; break; + case FASTRPC_CONTROL_RPC_POLL: + err =3D fastrpc_manage_poll_mode(fl, cp->lp.enable, cp->lp.latency); + break; default: err =3D -EBADRQC; break; --=20 2.17.1