From patchwork Mon Jan 27 04:42:38 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ekansh Gupta X-Patchwork-Id: 13950981 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5ACA61FC7C6; Mon, 27 Jan 2025 04:43:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.180.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737952990; cv=none; b=SJTh2KWhVaVhMgp5DOO1M+HegJZaOHwH2uokWJfwA142KtHRO92TrnBwmAnqt/kF1QQou8fEO8nMJS2NGJPMzNzVbpIshwAFgkS9LGnv+bZw1/I0D5ooFD8KZn6/wh6bntLN5UOpdIFf69mkmcpS8kUhsegqlCvhiFapb8spMug= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737952990; c=relaxed/simple; bh=YbCwJpDf/fyWg199r3u5kHp2qWjzEGMzdgJJzaYwmq8=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=pVukiELE0OVFSBqI83SQml+OFJk8lk5iMApO+zK2WAnqsEwEKKxTqH26YbXB+Yc4aGxxgcP6ApzO7Y8yySwY4xvbFFtDSTVUIhRHYegx4gEN9BhSNSysbKu0cpGlozSZWtEoFRkqllZLNCol+9tgehDkFa5rWGNB+hZ8G04sPDs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com; spf=pass smtp.mailfrom=quicinc.com; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b=ZS5PFa/k; arc=none smtp.client-ip=205.220.180.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=quicinc.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=quicinc.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=quicinc.com header.i=@quicinc.com header.b="ZS5PFa/k" Received: from pps.filterd (m0279868.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 50R1ccp9008632; Mon, 27 Jan 2025 04:43:03 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= M01EAUmc0GjQN+utSYliCT+8oEL5CJS4CvJ8Ro1ooiI=; b=ZS5PFa/kpFEn1b5E 1LvjDRpG8tRvFEP5L5IdCH2fkKiNIqubSSHM3oMiAkr1zZn3GICSrU52xYVfzmMN je9EoSzTrv7/52jhT5c08PdNu4YXSV14ZOACdNPIC2zounKA3V2ow556Wmq1EOPm WN7AqM9w5wF5UNSaQ61c5kbfpCyPLkTFMqWLc6VuhvBPcqoth5QAmANC2FeaL6ye 0Hqp+QRYrCGwrs4mHwgn31nYEPkEi3z662D1kEzC7+kMsNM5t5nuqT7WOGXIibwY hSArkiSZTJogejfNKBmLAey9FcABNGR+t3yEziRpcOiVN0xblqH3Vugo/uoEYD8S XIaFQA== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 44dwg0rcun-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 27 Jan 2025 04:43:03 +0000 (GMT) Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA04.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 50R4h2EU003085 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 27 Jan 2025 04:43:02 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 15.2.1544.9; Sun, 26 Jan 2025 20:42:59 -0800 From: Ekansh Gupta To: , CC: , , , , , Subject: [PATCH v2 4/5] misc: fastrpc: Add polling mode support for fastRPC driver Date: Mon, 27 Jan 2025 10:12:38 +0530 Message-ID: <20250127044239.578540-5-quic_ekangupt@quicinc.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250127044239.578540-1-quic_ekangupt@quicinc.com> References: <20250127044239.578540-1-quic_ekangupt@quicinc.com> Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) 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: OifRupQm49DrCmBHe1Hn-I6aOOAycuMm X-Proofpoint-ORIG-GUID: OifRupQm49DrCmBHe1Hn-I6aOOAycuMm X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-01-27_01,2025-01-27_01,2024-11-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 phishscore=0 spamscore=0 malwarescore=0 lowpriorityscore=0 clxscore=1015 mlxlogscore=999 impostorscore=0 adultscore=0 bulkscore=0 mlxscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2501270036 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 --- drivers/misc/fastrpc.c | 122 +++++++++++++++++++++++++++++++++--- include/uapi/misc/fastrpc.h | 3 +- 2 files changed, 114 insertions(+), 11 deletions(-) diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c index cfacee0dded5..257a741af115 100644 --- a/drivers/misc/fastrpc.c +++ b/drivers/misc/fastrpc.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -38,6 +39,7 @@ #define FASTRPC_CTX_MAX (256) #define FASTRPC_INIT_HANDLE 1 #define FASTRPC_DSP_UTILITIES_HANDLE 2 +#define FASTRPC_MAX_STATIC_HANDLE (20) #define FASTRPC_CTXID_MASK (0xFF0) #define INIT_FILELEN_MAX (2 * 1024 * 1024) #define INIT_FILE_NAMELEN_MAX (128) @@ -106,6 +108,19 @@ #define miscdev_to_fdevice(d) container_of(d, struct fastrpc_device, miscdev) +/* 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) + +/* Response types supported for RPC calls */ +enum fastrpc_response_flags { + /* normal job completion glink response */ + NORMAL_RESPONSE = 0, + /* process updates poll memory instead of glink response */ + POLL_MODE = 1, +}; + static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp", "sdsp", "cdsp", "cdsp1" }; struct fastrpc_phy_page { @@ -238,9 +253,16 @@ struct fastrpc_invoke_ctx { u32 sc; u64 *fdlist; u32 *crclist; + u32 *poll; void __user *crc; u64 ctxid; u64 msg_sz; + /* Threads poll for specified timeout and fall back to glink wait */ + u64 poll_timeout; + /* work done status flag */ + bool is_work_done; + /* response flags from remote processor */ + enum fastrpc_response_flags rsp_flags; struct kref refcount; struct list_head node; /* list of ctxs */ struct completion work; @@ -258,6 +280,7 @@ struct fastrpc_invoke_ctx { struct fastrpc_ctx_args { struct fastrpc_invoke_args *args; void __user *crc; + u64 poll_timeout; }; struct fastrpc_session_ctx { @@ -619,11 +642,14 @@ static struct fastrpc_invoke_ctx *fastrpc_context_alloc( fastrpc_channel_ctx_get(cctx); ctx->crc = cargs->crc; + ctx->poll_timeout = cargs->poll_timeout; ctx->sc = sc; ctx->retval = -1; ctx->pid = current->pid; ctx->client_id = user->client_id; ctx->cctx = cctx; + ctx->rsp_flags = NORMAL_RESPONSE; + ctx->is_work_done = false; init_completion(&ctx->work); INIT_WORK(&ctx->put_work, fastrpc_context_put_wq); @@ -882,7 +908,8 @@ static int fastrpc_get_meta_size(struct fastrpc_invoke_ctx *ctx) sizeof(struct fastrpc_invoke_buf) + sizeof(struct fastrpc_phy_page)) * ctx->nscalars + sizeof(u64) * FASTRPC_MAX_FDLIST + - sizeof(u32) * FASTRPC_MAX_CRCLIST; + sizeof(u32) * FASTRPC_MAX_CRCLIST + + sizeof(u32); return size; } @@ -975,6 +1002,8 @@ static int fastrpc_get_args(u32 kernel, struct fastrpc_invoke_ctx *ctx) pages = fastrpc_phy_page_start(list, ctx->nscalars); ctx->fdlist = (u64 *)(pages + ctx->nscalars); ctx->crclist = (u32 *)(ctx->fdlist + FASTRPC_MAX_FDLIST); + ctx->poll = (u32 *)(ctx->crclist + FASTRPC_MAX_CRCLIST); + args = (uintptr_t)ctx->buf->virt + metalen; rlen = pkt_size - metalen; ctx->rpra = rpra; @@ -1145,6 +1174,72 @@ static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx, } +static int poll_for_remote_response(struct fastrpc_invoke_ctx *ctx, u64 timeout) +{ + int err = -EIO, i, j; + + /* poll on memory for DSP response. Return failure on timeout */ + for (i = 0, j = 0; i < timeout; i++, j++) { + if (*ctx->poll == FASTRPC_POLL_RESPONSE) { + err = 0; + ctx->is_work_done = true; + ctx->retval = 0; + break; + } + if (j == FASTRPC_POLL_TIME_MEM_UPDATE) { + /* make sure that all poll memory writes by DSP are seen by CPU */ + dma_rmb(); + j = 0; + } + udelay(1); + } + return err; +} + +static inline int fastrpc_wait_for_response(struct fastrpc_invoke_ctx *ctx, + u32 kernel) +{ + int err = 0; + + if (kernel) { + if (!wait_for_completion_timeout(&ctx->work, 10 * HZ)) + err = -ETIMEDOUT; + } else { + err = wait_for_completion_interruptible(&ctx->work); + } + + return err; +} + +static int fastrpc_wait_for_completion(struct fastrpc_invoke_ctx *ctx, + u32 kernel) +{ + int err; + + do { + switch (ctx->rsp_flags) { + case NORMAL_RESPONSE: + err = fastrpc_wait_for_response(ctx, kernel); + if (err || ctx->is_work_done) + return err; + break; + case POLL_MODE: + err = poll_for_remote_response(ctx, ctx->poll_timeout); + /* If polling timed out, move to normal response mode */ + if (err) + ctx->rsp_flags = NORMAL_RESPONSE; + break; + default: + err = -EBADR; + dev_dbg(ctx->fl->sctx->dev, + "unsupported response type:0x%x\n", ctx->rsp_flags); + break; + } + } while (!ctx->is_work_done); + + return err; +} + static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, u32 handle, u32 sc, struct fastrpc_ctx_args *cargs) @@ -1180,16 +1275,20 @@ static int fastrpc_internal_invoke(struct fastrpc_user *fl, u32 kernel, if (err) goto bail; - if (kernel) { - if (!wait_for_completion_timeout(&ctx->work, 10 * HZ)) - err = -ETIMEDOUT; - } else { - err = wait_for_completion_interruptible(&ctx->work); - } + if (ctx->poll_timeout != 0 && handle > FASTRPC_MAX_STATIC_HANDLE + && fl->pd == USER_PD) + ctx->rsp_flags = POLL_MODE; + err = fastrpc_wait_for_completion(ctx, kernel); if (err) goto bail; + if (!ctx->is_work_done) { + err = -ETIMEDOUT; + dev_dbg(fl->sctx->dev, "Invalid workdone state for handle 0x%x, sc 0x%x\n", + handle, sc); + goto bail; + } /* make sure that all memory writes by DSP are seen by CPU */ dma_rmb(); /* populate all the output buffers with results */ @@ -1769,7 +1868,7 @@ static int fastrpc_invokev2(struct fastrpc_user *fl, char __user *argp) return -EFAULT; /* Check if all reserved fields are zero */ - for (i = 0; i < 16; i++) { + for (i = 0; i < 14; i++) { if (inv2.reserved[i] != 0) return -EINVAL; } @@ -1779,6 +1878,7 @@ static int fastrpc_invokev2(struct fastrpc_user *fl, char __user *argp) return -ENOMEM; cargs->crc = (void __user *)(uintptr_t)inv2.crc; + cargs->poll_timeout = inv2.poll_timeout; err = fastrpc_remote_invoke(fl, &inv2.inv, cargs); kfree(cargs); @@ -2581,12 +2681,14 @@ static int fastrpc_rpmsg_callback(struct rpmsg_device *rpdev, void *data, ctx = idr_find(&cctx->ctx_idr, ctxid); spin_unlock_irqrestore(&cctx->lock, flags); + /* Ignore this failure as context returned will be NULL for polling mode */ if (!ctx) { - dev_err(&rpdev->dev, "No context ID matches response\n"); - return -ENOENT; + dev_dbg(&rpdev->dev, "No context ID matches response\n"); + return 0; } ctx->retval = rsp->retval; + ctx->is_work_done = true; complete(&ctx->work); /* diff --git a/include/uapi/misc/fastrpc.h b/include/uapi/misc/fastrpc.h index 406b80555d41..1920c537bbbf 100644 --- a/include/uapi/misc/fastrpc.h +++ b/include/uapi/misc/fastrpc.h @@ -84,7 +84,8 @@ struct fastrpc_invoke { struct fastrpc_invoke_v2 { struct fastrpc_invoke inv; __u64 crc; - __u32 reserved[16]; + __u64 poll_timeout; + __u32 reserved[14]; }; struct fastrpc_init_create {