From mboxrd@z Thu Jan 1 00:00:00 1970 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 E8E44E555; Sat, 23 Nov 2024 04:37:16 +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=1732336639; cv=none; b=WRNsnLhA5ROmapTILdUsItb0yofbXssg7Xbg4pXLqRo0eKFL/4/J/dmwngeJZaliCEmCHT2xxwgMjJG/S7WgaV9ejlQeBOOlMsrvaZ2XrQG4FIf9rtKqDSssKmry3rH/ZL57tmHeSmJceHRmFuAqCPXJT9pYF4jLAMxYWpwr2o4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1732336639; c=relaxed/simple; bh=IEfmIuvf4RAZiKcvZ/bEeGLP0YpTuFTW7nzn8ETa25s=; h=Date:From:To:CC:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PrAVE6xrFWuCY2jWhj5FGY6wiHBiFGKNdi4axauK5ZxxDf6zluvYODakGND06oWw8edU/Hy+3rpEmWNQxeXuxqvtfPOKDgvvfybdNFQHinANvzSY4bzkgD9JCXFrN7uVWoJKfozFX/IjttdEk6vGlyapEzhXn3v26yXFE93+dqU= 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=jj+6P33+; 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="jj+6P33+" Received: from pps.filterd (m0279869.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 4AN4Gw1w005848; Sat, 23 Nov 2024 04:37:04 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=c2xEIpSPn21EhzqyOoYBSY89 AGIccID/ZJQJM8/dhek=; b=jj+6P33+PlgqHvQFfhcImgUh4cjOFDqQbVNThrhi Lx3axgsvp9bEde24hcjT+umDuO9x3zYI5PB2Q1JjEW0Ms+sfsvPaswnaQLoiZGpD rRGEsawybkoUt3mDlwpjAOwnTjLh5vAzjIwXxhfRzh9WvTOgQDkRip6iQ0pXVDvz V6RBEWXd3za1SueGSx0/4/JM+1jTFtDt9Ub4mIW5VH4ngzEKH1rqjeVVx2apHFGY MMYcbY/mv2+56KsbtANCqhAF7LtcOth1p9Hwd/6+sOxRluRCDQbgtDJrz4nH+NeY EAuNg6LCU5r44LKnboETVCx9qmxA9EJS1/y1qQAwrM9zQA== Received: from nasanppmta01.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 43362685fe-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 23 Nov 2024 04:37:03 +0000 (GMT) Received: from nasanex01b.na.qualcomm.com (nasanex01b.na.qualcomm.com [10.46.141.250]) by NASANPPMTA01.qualcomm.com (8.18.1.2/8.18.1.2) with ESMTPS id 4AN4b24w021123 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sat, 23 Nov 2024 04:37:02 GMT Received: from hu-varada-blr.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; Fri, 22 Nov 2024 20:36:59 -0800 Date: Sat, 23 Nov 2024 10:06:55 +0530 From: Varadarajan Narayanan To: Md Sadre Alam CC: , , , , , , , , , Subject: Re: [PATCH] dmaengine: qcom: bam_dma: Avoid writing unavailable register Message-ID: References: <20241122071649.2618320-1-quic_mdalam@quicinc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20241122071649.2618320-1-quic_mdalam@quicinc.com> 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: NRZFCp9wre6-FjG--Mb6mOSdEovYI7qI X-Proofpoint-ORIG-GUID: NRZFCp9wre6-FjG--Mb6mOSdEovYI7qI 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 priorityscore=1501 clxscore=1011 phishscore=0 spamscore=0 adultscore=0 impostorscore=0 mlxscore=0 malwarescore=0 suspectscore=0 mlxlogscore=999 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2409260000 definitions=main-2411230034 On Fri, Nov 22, 2024 at 12:46:49PM +0530, Md Sadre Alam wrote: > Avoid writing unavailable register in BAM-Lite mode. > BAM_DESC_CNT_TRSHLD register is unavailable in BAM-Lite > mode. Its only available in BAM-NDP mode. So avoid writing > this register for clients who is using BAM-Lite mode. > > Signed-off-by: Md Sadre Alam > --- > drivers/dma/qcom/bam_dma.c | 22 ++++++++++++++-------- > 1 file changed, 14 insertions(+), 8 deletions(-) > > diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c > index d43a881e43b9..13a08c03746b 100644 > --- a/drivers/dma/qcom/bam_dma.c > +++ b/drivers/dma/qcom/bam_dma.c > @@ -59,6 +59,9 @@ struct bam_desc_hw { > #define DESC_FLAG_NWD BIT(12) > #define DESC_FLAG_CMD BIT(11) > > +#define BAM_LITE 0x13 > +#define BAM_NDP 0x20 > + > struct bam_async_desc { > struct virt_dma_desc vd; > > @@ -398,6 +401,7 @@ struct bam_device { > > /* dma start transaction tasklet */ > struct tasklet_struct task; > + u32 bam_revision; > }; > > /** > @@ -441,8 +445,9 @@ static void bam_reset(struct bam_device *bdev) > writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL)); > > /* set descriptor threshold, start with 4 bytes */ > - writel_relaxed(DEFAULT_CNT_THRSHLD, > - bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); > + if (bdev->bam_revision >= BAM_LITE && bdev->bam_revision < BAM_NDP) > + writel_relaxed(DEFAULT_CNT_THRSHLD, > + bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); > > /* Enable default set of h/w workarounds, ie all except BAM_FULL_PIPE */ > writel_relaxed(BAM_CNFG_BITS_DEFAULT, bam_addr(bdev, 0, BAM_CNFG_BITS)); > @@ -1000,9 +1005,9 @@ static void bam_apply_new_config(struct bam_chan *bchan, > maxburst = bchan->slave.src_maxburst; > else > maxburst = bchan->slave.dst_maxburst; > - > - writel_relaxed(maxburst, > - bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); > + if (bdev->bam_revision >= BAM_LITE && bdev->bam_revision < BAM_NDP) > + writel_relaxed(maxburst, > + bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD)); > } > > bchan->reconfigure = 0; > @@ -1192,10 +1197,11 @@ static int bam_init(struct bam_device *bdev) > u32 val; > > /* read revision and configuration information */ > - if (!bdev->num_ees) { > - val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION)); > + val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION)); > + if (!bdev->num_ees) > bdev->num_ees = (val >> NUM_EES_SHIFT) & NUM_EES_MASK; > - } > + > + bdev->bam_revision = val & 0xff; Use REVISION_MASK instead of 0xff -Varada > /* check that configured EE is within range */ > if (bdev->ee >= bdev->num_ees) > -- > 2.34.1 >