From mboxrd@z Thu Jan 1 00:00:00 1970 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 5E4F0387361 for ; Fri, 26 Jun 2026 15:34:34 +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=1782488075; cv=none; b=O71EDWnE+/u4FA2HJe7PAkMYR1SpEpol6NMC2WhKpoTUvCNeJUv54BneIiFTi+cew8IE0b6BaCgPIdWAdQiVgKFEeXT7Vx1hjSxQYjm6dZFjkhv1nfDdiiOfn21t3WKNiNPMvx/1jDf+qpfeb1drcIL+dzV70m975gSaBaNPGao= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782488075; c=relaxed/simple; bh=uycrAyaNRqPC1wT03GAKc8SD5LIJHNc3+Z03A8sdBHE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fM8WKA2Tga8SIcLYR0tIqD4n6J+66FEEMrVhYJsKWzBt8QKCWgieOhPgMx0/iuHC/464KIUd4EGG1PcjkjF3CpoB2UF3R96QngqAyDD3bRvGzGsbGQ0ABpwgjX8KfXoK5RHUHk/15iHl/NuhPireRh5cDoKAC8tYaGo2EVijN+Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com; spf=pass smtp.mailfrom=oss.qualcomm.com; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b=JdtYaAnt; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=GYI1glJr; arc=none smtp.client-ip=205.220.168.131 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oss.qualcomm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=qualcomm.com header.i=@qualcomm.com header.b="JdtYaAnt"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="GYI1glJr" Received: from pps.filterd (m0279866.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 65QF3g1w1197994 for ; Fri, 26 Jun 2026 15:34:33 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=qualcomm.com; h= cc:content-transfer-encoding:content-type:date:from:in-reply-to :message-id:mime-version:references:subject:to; s=qcppdkim1; bh= CWeBwIab1i2IzhQduB2JbzOKce381YUPIvSMgEmg3JA=; b=JdtYaAnt+IQ2zkHa xbYaoXybk5idkMsh8AJKfDK1H1dgHo78sEDOyWi99zboNChKkNhXOpdhJJPXW4n3 MCEDwJ5dsunN1SebLajsZoa7j5v3/Rig++djXlcL332tu/qE3aOj87Qfd9gACbv8 bVvIMTi2vvCSKblgHaEwfCJQAxizheRh4e8MGTVp3cF9xrLGYFmTlKkqVkLrpkQI TZuqIxMgmPs1yZr+m8b1gD/+qqaN0LWLbCG3OZ9RueP1RtaRCICprKXExt2YXWBr VtVe3hh3H4brlfpcKzZkJ5o9+M3ObQFhrrnlXvIcAGo7MOqPjfsRD1KzRI9mXwSo cgAW1g== Received: from mail-qt1-f199.google.com (mail-qt1-f199.google.com [209.85.160.199]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4f1t0qrjwu-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Fri, 26 Jun 2026 15:34:33 +0000 (GMT) Received: by mail-qt1-f199.google.com with SMTP id d75a77b69052e-51a15cef334so1456001cf.3 for ; Fri, 26 Jun 2026 08:34:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1782488073; x=1783092873; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to :content-type; bh=CWeBwIab1i2IzhQduB2JbzOKce381YUPIvSMgEmg3JA=; b=GYI1glJr/ONXthAWlo01gyiz/CitvfWgR+K3ondbX8ICaO8vU3cUVs2tWk0EuDAM8U KhgVO9bdMwQxZy1MDbuVXWONgdHSE3scb6uoHiG5h7v67PEZJQzEouVg2h9JghSdPpzV V7s4tlZzkKyUjsZcp8IXdgLHkxUY7Wo8mbW23hj3bAvak6MbYA4EKHYwEhPDM1yn+JaD wmBcjnJVHzX6uNJXT5SgwYBh1A8NisY1PVjWtZMUx+wkR/22DO1AtW3l9RmfPHqZ/n5R o4777g9E7s2LnWuTsrHukNpJ+dtNsv80drDkvIxep8ocWetoc/1AI7l5c/A86RW4o2ol SMPw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782488073; x=1783092873; h=content-transfer-encoding:content-type:in-reply-to:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to:content-type; bh=CWeBwIab1i2IzhQduB2JbzOKce381YUPIvSMgEmg3JA=; b=rGfKrMu4sisOh0yKQ0z5uOMnKKNzZ7T9jtCJk7gSzaB0xPsv1qFWYr4mX/CEsVAYPC w9+jpq0rL/XpWMxRN9Hq/F23zvQh1sDqH9DzYIjbuHptWsDd1LuQ68gsnR8iCCRWSyqG dS4jYvp0X4GELfbZKBgL6ccxo9s+DprZqUq4aPA9cGzMp9ZykAIxoBlcNEq0HsdV8iWB jTXEUa0K+WjGgt6L4i7ZwN7TYkex8R+Ll/lgyqfaVJGTCuRAT2JQQg+ip+1R3G3Dhevc Ga4G1y0CoB3d+yOU6gkseL4593xcvLeWOMLUgzCyjcsqMLd831v15aU8HecxwdzijsAS R5fQ== X-Forwarded-Encrypted: i=1; AFNElJ9NrfxN7ugQIhw5e2INI1cC80FKIhb/OQ//rlVZbq3fItDxawQf727FiTmdWa8lPkI3YRcHRT8Y5FBN@vger.kernel.org X-Gm-Message-State: AOJu0YwRT0cyxLuTDX/Xdfd65Zj70WZv4ZbTJRHZQ4lV8WE6H1OX/SLA Sf/7LE6rKrw0as4ZOWa3druKjzyWFQOvT2l+iqHT+iwS4Y5f77xSg0yVwhyFTnkr8v/FAd2CvK8 j9TZRaZT5izvkzIGzajY4G76ceWSzgIqMxZg00tHC2M5lQBwWF32BzcuDOUr1B4C2 X-Gm-Gg: AfdE7ckJrHx7IdClotoyLGlnBT8+mhtMO+eA9kRQtvE/yMhFZmiKhWEv2ErQVHxFnFv ewg6ubJxQ8Ee9rZlXqgfWY99akJeRWpcQhcopY+pSmH7+WYmKB0xn1MhSxDdTsCxxvUE3erKdZc o4jG5HFB9VnYS2BxaO2mlq6u+rnwrNCu28641cxjmF27wf9Kt+dg64OIrKLM+9qat+hwppJDeLY 17UzODNQ4mV/A+X+At6CGuZMaaPsZacySFrnmOgkO3s70sM2wXEgum6M4z3Hp/tm1i5rP3PMHyH gDD+g1zaTnsqjlaOdxaCgz9pnbaDycjwye/3VrpCZ0zJke/SYABqOpcNwKUDKBpb6x2MrkT18oV 1obzBIRGBLt0MoWcMFF5yc3hms7nPntkkqu4= X-Received: by 2002:a05:622a:11d2:b0:509:2a92:8088 with SMTP id d75a77b69052e-51a726e0126mr68689211cf.1.1782488072515; Fri, 26 Jun 2026 08:34:32 -0700 (PDT) X-Received: by 2002:a05:622a:11d2:b0:509:2a92:8088 with SMTP id d75a77b69052e-51a726e0126mr68688601cf.1.1782488071782; Fri, 26 Jun 2026 08:34:31 -0700 (PDT) Received: from [192.168.120.170] ([178.235.128.140]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-c11fbba8b61sm341289566b.4.2026.06.26.08.34.29 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 26 Jun 2026 08:34:31 -0700 (PDT) Message-ID: Date: Fri, 26 Jun 2026 17:34:28 +0200 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 2/2] spi: qcom-geni: Add property to force GSI mode To: Mukesh Savaliya , Pengyu Luo , Dmitry Baryshkov Cc: Mark Brown , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Andy Gross , Bjorn Andersson , linux-arm-msm@vger.kernel.org, linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260614083424.464132-1-mitltlatltl@gmail.com> <20260614083424.464132-2-mitltlatltl@gmail.com> <3451facc-4a2e-43bf-ba13-944488bce437@oss.qualcomm.com> <14491fd8-f785-4404-878b-5764bb8fd593@oss.qualcomm.com> Content-Language: en-US From: Konrad Dybcio In-Reply-To: <14491fd8-f785-4404-878b-5764bb8fd593@oss.qualcomm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Proofpoint-Spam-Info: AW1haW4tMjYwNjI2MDEyOSBTYWx0ZWRfX6yTHmJhNY9CA USqk4LYrp5k4/b0oerAULZQ4s5tl/pQ1aOvzMqfpRNfl7uIg7S3d4Hf0ZpY9dqop4h6xrPcVl3u SYBTYO1/OcTqMC3t1P1Ssf+aM9N1n4w= X-Proofpoint-GUID: f8T8ATeOxtnRXWvmx5SsyCqBX8UwMdrI X-Authority-Analysis: v=2.4 cv=StqgLvO0 c=1 sm=1 tr=0 ts=6a3e9c09 cx=c_pps a=WeENfcodrlLV9YRTxbY/uA==:117 a=PRfkaYvzSr8QmIIGAkY2Sg==:17 a=IkcTkHD0fZMA:10 a=FelO9ux0wxsA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=YMgV9FUhrdKAYTUUvYB2:22 a=EUspDBNiAAAA:8 a=KdbZC8JMYa_JGPUaySMA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=kacYvNCVWA4VmyqE58fU:22 X-Proofpoint-ORIG-GUID: f8T8ATeOxtnRXWvmx5SsyCqBX8UwMdrI X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwNjI2MDEyOSBTYWx0ZWRfX+ZOzLpSraPAU iwKHv4MBCI2OSBnCLlaCCYpVvZwS4EhRDLgw/JvSMfuzTos7FLW6b0FAhr4C1MMDXl6juJh9zhN kbFGuvBBH/LVtH5xAgJR5BLN+s/YuvnYwx0aJcJcF4vxLXKS4blzBkGx1oqorcoS7e+NagD4sDY 1+ePTyMugVLrh/TCyvHvhL4NQO1G0tQSmYJHIpv8M03IkkQZVCjgDUMu6giudpfJVpbrFLZ4xMn CsRwH+Slg/uTs1MHEnDt2NuLZYq7lr7IOb+JO87oePsWIhx2GXg8vZ17bHRnNXhcq4zQq2F37k/ xbE6dfCFLaDEMOZzyA3MjIAdgmIV8gjMESsLDOzyjl86di23FJPDgCCuJz/xYqfZhz9JoSDHkxW /fqKl9jeU/416pjauoLH2xUV1kYoZe7fTAmwIFL4P6wpkP86DRwq8nhGhjhJJ9GkNhHm57Ej1l3 61nXiUYM2/zN7gXnuMg== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.125,FMLib:17.12.100.49 definitions=2026-06-26_03,2026-06-26_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 lowpriorityscore=0 bulkscore=0 adultscore=0 impostorscore=0 spamscore=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 clxscore=1015 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2606260129 On 6/25/26 11:06 AM, Mukesh Savaliya wrote: > Hi Konrad, sorry for late response. > > On 6/15/2026 5:12 PM, Konrad Dybcio wrote: >> On 6/15/26 6:25 AM, Pengyu Luo wrote: >>> On Mon, Jun 15, 2026 at 5:18 AM Dmitry Baryshkov >>> wrote: >>>> >>>> On Sun, Jun 14, 2026 at 04:34:24PM +0800, Pengyu Luo wrote: >>>>> Some devices (such as gaokun3) do not disable FIFO mode, causing the >>>>> driver to fallback to FIFO mode by default. However, these platforms >>>>> also support GSI mode, which is highly preferred for certain >>>>> peripherals like SPI touchscreens to improve performance. >>>>> >>>>> Introduce the "qcom,force-gsi-mode" device property to hint and force >>>>> the controller into GSI mode during initialization. >>>> >>>> Ideally, this should be decided by the SPI controller based on the >>>> requirements. Another option would be to prefer GSI for all transfers if >>>> it is available, ignoring the FIFO even if it is not disabled. >>>> >>> >>> I have read reviews. Can we check if the compatible >>> "qcom,sm6350-gpi-dma" is in DT? If the gpi dma controller is >>> presented, then we enable GSI mode. >> >> >> This hunk is very odd: >> >> /* >>   * in case of failure to get gpi dma channel, we can still do the >>   * FIFO mode, so fallthrough >>   */ >> dev_warn(mas->dev, "FIFO mode disabled, but couldn't get DMA, fall back to FIFO mode\n"); >> >> In my understanding, GSI DMA mode is always preferable. +Mukesh, do >> you have any insights? >> > GSI mode is preferable but if for some reason it fails, we try to continue with the FIFO mode. Just fallback mechanism. So, would making GSI the default and FIFO the fallback option sound good? Konrad