From patchwork Mon Dec 9 07:50:33 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jyothi Kumar Seerapu X-Patchwork-Id: 13899034 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 6371C5588B; Mon, 9 Dec 2024 07:50:55 +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=1733730657; cv=none; b=lWhgiKQ49+I++6I3CROxbgf4uzwC197gpHYtUb3EM57xcagpf6uVRswFdKVmgKyuw/lIOllcK/BeAd9HSgenJW9FeW2+PMuGLTR79bQ3HZfp8kX18F9LhYsz6XSOm/piSP6Kn1vSxjzX1nERskW1FOe7Q5cK7Uv7+g9bviIzACk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733730657; c=relaxed/simple; bh=auazOFGND/yAf5G+6jGRmxDE2uDZn3SMEVPVM7giZbU=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=rQ3DKNZbJV3ZBKW/2DoCRH24li+K5IGS9NTHDky10yJwzRzAOZO7cqGD85kPPdcAvot6NHMApksuNHCihHN6W0vFWQWe033kwB8lA0ewdcnfkPyTU35uE1V2TZPB/ie9DQlGi1P5tJ8KOpHkq/XfwNqhem04HYliRfagv0iX/mc= 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=IhR5s7uF; 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="IhR5s7uF" 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 4B8KeSQc020616; Mon, 9 Dec 2024 07:50:50 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h= cc:content-type:date:from:message-id:mime-version:subject:to; s= qcppdkim1; bh=0VPlfYGdLQ3wfIEV6ZiIRshkflZhmoztvCNqNToLX6M=; b=Ih R5s7uFIsmgpnxr9nbd36ZwJ+Y1HZzKPzy5yIgDMQb4MvQlzUFULh+joTP5gJUlys ueC3/zRAtm47Fv3GyGi36zJ7qVdHyCFJrSyUyqLBRw5fW3MCB0p/DiPsIq6m+ZkH i7Zi4uE74FF7Ati4YRDT69IqaY9kyTdsjDUxlvz/2Md25KcYKtKyVtqc4BuO3meY hPGA/We/casDZg2mZxzWw20TzDbRuvIIyQd4RCpJQ7lYPpKilMTj9iSDQZs70sTs rzcbb0yfJC48AE8QmJW15zGE/oGJeubz20pNUlNg5UbE/g+VtfO6u/rnvOIbdqp1 x5VNbYcgR5QR944FTLUA== Received: from nasanppmta02.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 43cdpgkukp-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Dec 2024 07:50:50 +0000 (GMT) Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA02.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 4B97on5V027936 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 9 Dec 2024 07:50:49 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; Sun, 8 Dec 2024 23:50:46 -0800 From: Jyothi Kumar Seerapu To: Vinod Koul CC: , , , , Subject: [PATCH v5] dmaengine: qcom: gpi: Add GPI immediate DMA support for SPI protocol Date: Mon, 9 Dec 2024 13:20:33 +0530 Message-ID: <20241209075033.16860-1-quic_jseerapu@quicinc.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk X-Mailing-List: linux-arm-msm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) 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-GUID: fOyYx7c7ku0RLEjGLN5iXPozNefUS5cd X-Proofpoint-ORIG-GUID: fOyYx7c7ku0RLEjGLN5iXPozNefUS5cd 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 lowpriorityscore=0 adultscore=0 clxscore=1015 suspectscore=0 mlxscore=0 priorityscore=1501 phishscore=0 mlxlogscore=999 spamscore=0 malwarescore=0 bulkscore=0 impostorscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2412090059 The DMA TRE(Transfer ring element) buffer contains the DMA buffer address. Accessing data from this address can cause significant delays in SPI transfers, which can be mitigated to some extent by utilizing immediate DMA support. QCOM GPI DMA hardware supports an immediate DMA feature for data up to 8 bytes, storing the data directly in the DMA TRE buffer instead of the DMA buffer address. This enhancement enables faster SPI data transfers. This optimization reduces the average transfer time from 25 us to 16 us for a single SPI transfer of 8 bytes length, with a clock frequency of 50 MHz. Signed-off-by: Jyothi Kumar Seerapu Reviewed-by: Dmitry Baryshkov Reviewed-by: Neil Armstrong Tested-by: Neil Armstrong # on SM8550-QRD Tested-by: Neil Armstrong # on SM8650-QRD --- v4 -> v5: - For Immediate DMA, instead of making dma type as 0x10 and then enable 16th bit of dword3, directly updating the dma type as 0x11. Link to v4: https://lore.kernel.org/all/20241205170611.18566-1-quic_jseerapu@quicinc.com/ v3 -> v4: - Instead using extra variable(immediate_dma) for Immediate dma condition check, made it to inlined. - Removed the extra brackets around Immediate dma condition check. Link to v3: https://lore.kernel.org/lkml/20241204122059.24239-1-quic_jseerapu@quicinc.com/ v2 -> v3: - When to enable Immediate DMA support, control is moved to GPI driver from SPI driver. - Optimizations are done in GPI driver related to immediate dma changes. - Removed the immediate dma supported changes in qcom-gpi-dma.h file and handled in GPI driver. Link to v2: https://lore.kernel.org/all/20241128133351.24593-2-quic_jseerapu@quicinc.com/ https://lore.kernel.org/all/20241128133351.24593-3-quic_jseerapu@quicinc.com/ v1 -> v2: - Separated the patches to dmaengine and spi subsystems - Removed the changes which are not required for this feature from qcom-gpi-dma.h file. - Removed the type conversions used in gpi_create_spi_tre. Link to v1: https://lore.kernel.org/lkml/20241121115201.2191-2-quic_jseerapu@quicinc.com/ drivers/dma/qcom/gpi.c | 31 +++++++++++++++++++++++++------ 1 file changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/dma/qcom/gpi.c b/drivers/dma/qcom/gpi.c index 52a7c8f2498f..b1f0001cc99c 100644 --- a/drivers/dma/qcom/gpi.c +++ b/drivers/dma/qcom/gpi.c @@ -18,6 +18,7 @@ #include "../virt-dma.h" #define TRE_TYPE_DMA 0x10 +#define TRE_TYPE_IMMEDIATE_DMA 0x11 #define TRE_TYPE_GO 0x20 #define TRE_TYPE_CONFIG0 0x22 @@ -64,6 +65,7 @@ /* DMA TRE */ #define TRE_DMA_LEN GENMASK(23, 0) +#define TRE_DMA_IMMEDIATE_LEN GENMASK(3, 0) /* Register offsets from gpi-top */ #define GPII_n_CH_k_CNTXT_0_OFFS(n, k) (0x20000 + (0x4000 * (n)) + (0x80 * (k))) @@ -1711,6 +1713,7 @@ static int gpi_create_spi_tre(struct gchan *chan, struct gpi_desc *desc, dma_addr_t address; struct gpi_tre *tre; unsigned int i; + int len; /* first create config tre if applicable */ if (direction == DMA_MEM_TO_DEV && spi->set_config) { @@ -1763,14 +1766,30 @@ static int gpi_create_spi_tre(struct gchan *chan, struct gpi_desc *desc, tre_idx++; address = sg_dma_address(sgl); - tre->dword[0] = lower_32_bits(address); - tre->dword[1] = upper_32_bits(address); + len = sg_dma_len(sgl); - tre->dword[2] = u32_encode_bits(sg_dma_len(sgl), TRE_DMA_LEN); + /* Support Immediate dma for write transfers for data length up to 8 bytes */ + if (direction == DMA_MEM_TO_DEV && len <= 2 * sizeof(tre->dword[0])) { + /* + * For Immediate dma, data length may not always be length of 8 bytes, + * it can be length less than 8, hence initialize both dword's with 0 + */ + tre->dword[0] = 0; + tre->dword[1] = 0; + memcpy(&tre->dword[0], sg_virt(sgl), len); - tre->dword[3] = u32_encode_bits(TRE_TYPE_DMA, TRE_FLAGS_TYPE); - if (direction == DMA_MEM_TO_DEV) - tre->dword[3] |= u32_encode_bits(1, TRE_FLAGS_IEOT); + tre->dword[2] = u32_encode_bits(len, TRE_DMA_IMMEDIATE_LEN); + tre->dword[3] = u32_encode_bits(TRE_TYPE_IMMEDIATE_DMA, TRE_FLAGS_TYPE); + } else { + tre->dword[0] = lower_32_bits(address); + tre->dword[1] = upper_32_bits(address); + + tre->dword[2] = u32_encode_bits(len, TRE_DMA_LEN); + tre->dword[3] = u32_encode_bits(TRE_TYPE_DMA, TRE_FLAGS_TYPE); + } + + tre->dword[3] |= u32_encode_bits(direction == DMA_MEM_TO_DEV, + TRE_FLAGS_IEOT); for (i = 0; i < tre_idx; i++) dev_dbg(dev, "TRE:%d %x:%x:%x:%x\n", i, desc->tre[i].dword[0],