From nobody Wed Nov 27 02:39:28 2024 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) (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 792CB1F890F; Tue, 15 Oct 2024 12:08:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.168.131 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728994125; cv=none; b=EK3dg3wBJHBXbYIhsf0GdoADcfz80XzWA8DqMhBfhbTDeHmjFrgdtkTYoEJcZz+d1O+vNL8gwum8v1qBN/478V7me5oC44NfSgkIOuojruPKURVFvU86z2mz9uLacJclQywnOmN7s+uD2WnM19ED0vI8OZDNU9nBySbpUxyJ2cQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1728994125; c=relaxed/simple; bh=mj5RauSO/liewGiosP+B7urk0xGqdqBiGXVhuvMwJc8=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=YOe1l686uRcHVqR3co6tJ/4tcZC1VJi1BeKSbLzD5H+UvX5jxVKSHWyniVzbHAP8reEFmVZkm2eduq9l76Gpa1wJrApx/cOaFMzugKIpc6iGNUHNTWsAXPbF6kSLZOr2pT3DCWK+Q9NQv0ztDu5IX//DqH8EVBIjVw9HrODV1TY= 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=CSG9FKuk; arc=none smtp.client-ip=205.220.168.131 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="CSG9FKuk" Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 49FC5BoS023375; Tue, 15 Oct 2024 12:08:34 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=qcppdkim1; bh=P+4ofdEIAV7EXx+X3B4PmdFg yiGukoosZaG+P3Ti4U0=; b=CSG9FKukdA2oyjk/zgmW8yIFMDhkCKUgDXQ8X/jb FvEI1zjmP2nOrkmfFpNNuJRyIqp6IzBNehUCtXjjPzASgpqzr1NacqIAqIGNpTlk 2/B09j4pzeNftVgiyCEH+G79KYKvbI5z0ykS8X+HnBxXAYMFz2oF8TsaFv+yREGW zbw2XUW7RaqenY/mGZeUY4KRcv9wZLaV1kvKTPyophd2ppibLeOZu2oYzzVAYOG5 k36n2L5YDKb4G9IqNKvPwfrFYsnc0mFaaQNrxCuQDnXpFJ0m1i9nxR0AOLbZbHyc XLr5bVTnTM3IBS5i9qdnk4y5tI42S/I+cSMxnfkKE9LjMg== Received: from nasanppmta03.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 429r3b809j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 15 Oct 2024 12:08:33 +0000 (GMT) Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA03.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 49FC8XRY027419 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 15 Oct 2024 12:08:33 GMT Received: from hu-jseerapu-hyd.qualcomm.com (10.80.80.8) 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; Tue, 15 Oct 2024 05:08:27 -0700 From: Jyothi Kumar Seerapu To: Vinod Koul , Rob Herring , "Krzysztof Kozlowski" , Conor Dooley , "Bjorn Andersson" , Konrad Dybcio , Andi Shyti , Sumit Semwal , =?UTF-8?q?Christian=20K=C3=B6nig?= CC: , , , , , , , , , , Subject: [PATCH v1 4/5] dmaengine: qcom: gpi: Add GPI Block event interrupt support Date: Tue, 15 Oct 2024 17:37:49 +0530 Message-ID: <20241015120750.21217-5-quic_jseerapu@quicinc.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20241015120750.21217-1-quic_jseerapu@quicinc.com> References: <20241015120750.21217-1-quic_jseerapu@quicinc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) 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-ORIG-GUID: aEFO6pLAIX0YeBZ9ROqnvKFdp91C0S1f X-Proofpoint-GUID: aEFO6pLAIX0YeBZ9ROqnvKFdp91C0S1f 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 bulkscore=0 mlxscore=0 priorityscore=1501 clxscore=1015 adultscore=0 lowpriorityscore=0 mlxlogscore=999 phishscore=0 malwarescore=0 suspectscore=0 spamscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2410150083 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" GSI hardware generates an interrupt for each transfer completion. For multiple messages within a single transfer, this results in receiving N interrupts for N messages, which can introduce significant software interrupt latency. To mitigate this latency, utilize Block Event Interrupt (BEI) only when an interrupt is necessary. When using BEI, consider splitting a single multi-message transfer into chunks of 64. This approach can enhance overall transfer time and efficiency. Signed-off-by: Jyothi Kumar Seerapu --- drivers/dma/qcom/gpi.c | 49 ++++++++++++++++++++++++++++++++ include/linux/dma/qcom-gpi-dma.h | 37 ++++++++++++++++++++++++ 2 files changed, 86 insertions(+) diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c index 3c89b4a88ac1..b8ca119114d2 100644 --- a/drivers/dma/qcom/gpi.c +++ b/drivers/dma/qcom/gpi.c @@ -1694,6 +1694,9 @@ static int gpi_create_i2c_tre(struct gchan *chan, str= uct gpi_desc *desc, =20 tre->dword[3] =3D u32_encode_bits(TRE_TYPE_DMA, TRE_FLAGS_TYPE); tre->dword[3] |=3D u32_encode_bits(1, TRE_FLAGS_IEOT); + + if (i2c->flags & QCOM_GPI_BLOCK_EVENT_IRQ) + tre->dword[3] |=3D u32_encode_bits(1, TRE_FLAGS_BEI); } =20 for (i =3D 0; i < tre_idx; i++) @@ -2099,6 +2102,52 @@ static int gpi_find_avail_gpii(struct gpi_dev *gpi_d= ev, u32 seid) return -EIO; } =20 +/** + * gpi_multi_desc_process() - Process received transfers from GSI HW + * @dev: pointer to the corresponding dev node + * @multi_xfer: pointer to the gpi_multi_xfer + * @num_xfers: total number of transfers + * @transfer_timeout_msecs: transfer timeout value + * @transfer_comp: completion object of the transfer + * + * This function is used to process the received transfers based on the + * completion events + * + * Return: On success returns 0, otherwise return error code + */ +int gpi_multi_desc_process(struct device *dev, struct gpi_multi_xfer *mult= i_xfer, + u32 num_xfers, u32 transfer_timeout_msecs, + struct completion *transfer_comp) +{ + int i; + u32 max_irq_cnt, time_left; + + max_irq_cnt =3D num_xfers / NUM_MSGS_PER_IRQ; + if (num_xfers % NUM_MSGS_PER_IRQ) + max_irq_cnt++; + + /* + * Wait for the interrupts of the processed transfers in multiple + * of 64 and for the last transfer. If the hardware is fast and + * already processed all the transfers then no need to wait. + */ + for (i =3D 0; i < max_irq_cnt; i++) { + reinit_completion(transfer_comp); + if (max_irq_cnt !=3D multi_xfer->irq_cnt) { + time_left =3D wait_for_completion_timeout(transfer_comp, + transfer_timeout_msecs); + if (!time_left) { + dev_err(dev, "%s: Transfer timeout\n", __func__); + return -ETIMEDOUT; + } + } + if (num_xfers > multi_xfer->msg_idx_cnt) + return 0; + } + return 0; +} +EXPORT_SYMBOL_GPL(gpi_multi_desc_process); + /* gpi_of_dma_xlate: open client requested channel */ static struct dma_chan *gpi_of_dma_xlate(struct of_phandle_args *args, struct of_dma *of_dma) diff --git a/include/linux/dma/qcom-gpi-dma.h b/include/linux/dma/qcom-gpi-= dma.h index 6680dd1a43c6..ca0465627a21 100644 --- a/include/linux/dma/qcom-gpi-dma.h +++ b/include/linux/dma/qcom-gpi-dma.h @@ -15,6 +15,12 @@ enum spi_transfer_cmd { SPI_DUPLEX, }; =20 +#define QCOM_GPI_BLOCK_EVENT_IRQ BIT(0) + +#define QCOM_GPI_MAX_NUM_MSGS 200 +#define NUM_MSGS_PER_IRQ 64 +#define MIN_NUM_OF_MSGS_MULTI_DESC 4 + /** * struct gpi_spi_config - spi config for peripheral * @@ -51,6 +57,29 @@ enum i2c_op { I2C_READ, }; =20 +/** + * struct gpi_multi_xfer - Used for multi transfer support + * + * @msg_idx_cnt: message index for the transfer + * @buf_idx: dma buffer index + * @unmap_msg_cnt: unampped transfer index + * @freed_msg_cnt: freed transfer index + * @irq_cnt: received interrupt count + * @irq_msg_cnt: transfer message count for the received irqs + * @dma_buf: virtual address of the buffer + * @dma_addr: dma address of the buffer + */ +struct gpi_multi_xfer { + u32 msg_idx_cnt; + u32 buf_idx; + u32 unmap_msg_cnt; + u32 freed_msg_cnt; + u32 irq_cnt; + u32 irq_msg_cnt; + void *dma_buf[QCOM_GPI_MAX_NUM_MSGS]; + dma_addr_t *dma_addr[QCOM_GPI_MAX_NUM_MSGS]; +}; + /** * struct gpi_i2c_config - i2c config for peripheral * @@ -65,6 +94,8 @@ enum i2c_op { * @rx_len: receive length for buffer * @op: i2c cmd * @muli-msg: is part of multi i2c r-w msgs + * @flags: true for block event interrupt support + * @multi_xfer: indicates transfer has multi messages */ struct gpi_i2c_config { u8 set_config; @@ -78,6 +109,12 @@ struct gpi_i2c_config { u32 rx_len; enum i2c_op op; bool multi_msg; + u8 flags; + struct gpi_multi_xfer multi_xfer; }; =20 +int gpi_multi_desc_process(struct device *dev, struct gpi_multi_xfer *mult= i_xfer, + u32 num_xfers, u32 tranfer_timeout_msecs, + struct completion *transfer_comp); + #endif /* QCOM_GPI_DMA_H */ --=20 2.17.1