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 58E843822BB for ; Wed, 2 Sep 2026 06:09:18 +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=1788329359; cv=none; b=bv5QSn6fA56XFfMdfcEmeSzg4nScXQruNRM06XXct4116n7TUSBrjLA/MvY7Po1D+pP1ZPVqJjtVpSC8NtM+TlKr4TZTg23kCDXlEMjof4iSGQ2O5mLVNQA4ZXQ1c+WVzQOpjo/j9dt5MHs5fBVMBxAJvBO/agHJf302WhipUiM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788329359; c=relaxed/simple; bh=2O2tLbCSCtHBMYey+e7A3uPt/HONNbOYonSDFLRuS6E=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Q2Mpk2EbC6Hfe4hyPnbgIa0SS3z+trUC43vweDQywE7/Kx5vQ5rkK50T/F+pkg4jW3CV2UIOEURwDVef+zbkw/orDiG6dFa2cxDxUvnHDNNKQp9aMdfpG5j1kVLA/Lbzsb9oCle9zfcpfHJrttmPOFPwQ9px7boYQ7HG0Ae1noA= 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=iY2IK87W; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b=aO2f6a0o; 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="iY2IK87W"; dkim=pass (2048-bit key) header.d=oss.qualcomm.com header.i=@oss.qualcomm.com header.b="aO2f6a0o" Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.18.1.11/8.18.1.11) with ESMTP id 6825YNSF076984 for ; Wed, 2 Sep 2026 06:09:17 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= rekHoOCBWmiKDF8X232OJC4hGvW2Rl9Y34JGuZYLqzg=; b=iY2IK87Wvd1cPHXj BEIzJxzXQgF5YJUqKc+O0//4SjcTUqNeqWB4IZqatIxHAQUhcdkNe2HuxeGqkQDe AS+DXJdRpQDmiqEGLhR/SiAZ7Aa0iGD2nXTcGkSBcY5EEAv37Xg+YmlgItF8227m I2i7Zl0caFKUTYvLEQ3HsiA+xisvHR/1XNAnGzqoqj9wFWgMzDW/29O7s2Js/s8e 3Mq6pKHr+EhWE5WyhB9JDvLKG9mOA13findwrYj8S/figRWE7Fci4zyxyThj9Kod xROgMtRfPZwRJ51q3dUbzh+XdSzSGOtelvkO1/7NQu/LLsI4FnOcRY46bVOzNJOS EBfB5A== Received: from mail-pg1-f200.google.com (mail-pg1-f200.google.com [209.85.215.200]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 4ge1wpawst-1 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NOT) for ; Wed, 02 Sep 2026 06:09:17 +0000 (GMT) Received: by mail-pg1-f200.google.com with SMTP id 41be03b00d2f7-cc1ca15334cso1071323a12.1 for ; Tue, 01 Sep 2026 23:09:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oss.qualcomm.com; s=google; t=1788329357; x=1788934157; 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=rekHoOCBWmiKDF8X232OJC4hGvW2Rl9Y34JGuZYLqzg=; b=aO2f6a0oMeu/5b4v2er9puwoGM4kvphKFpAmoQQliEkf02mhNxFHqs7pRI3gWQyx3+ Hoat+1BAR8tuJTpwh5AypjilVsTEolw+16odcce5nqK9FckNjij9uLaAgxSfpvPVZMVZ zZONqH0OlbFPgf3ET3gsq6xMp+9G7Ldhyg7xrxsH2r4CwjCXnc5MNVExLLYIEEZf8P1o AX7B2kXUqqyl04+jKImHvVGE0H+19mIOb4K1QbgNQoBw4/IkDheF4KupcXO1L7BvHuSI iLREw88Fau8HjGxiWz3YvGgBfhG0wPUf8aGaE6r99l41UrUCq9e1zzCC6df+kIUrXyiK VK2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1788329357; x=1788934157; 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=rekHoOCBWmiKDF8X232OJC4hGvW2Rl9Y34JGuZYLqzg=; b=O0Fijup3sqRVEwBwdHS2VmzFU7uUfKEv63b9oByu887hn9OabT3UuYio6LeOSaRbfm sLnubN8eRp9OO9WrcKkK1Q42yNlOb24mO3/+2KBJuTfi/SgYA14DN8jYPSuGEYR7M4s6 AlGE10lkca8Fiz/DBddZ45wbocVHRtNFyeyFTXT7Wo6soEJwQ1Zvi4bAqVU0zRu8+LTp 71Of5TyeI+344XsvoNOkqBMBvxIi+BffkdepO6wavuiIk89uNiyjnyYOwt2KQ63qtYRa /WxlYz1LHlbHHlKeG/prnGLrvY7dMRol1IabdxWWao8wcdgObICQVR/1RFiTE15La63j 6ajA== X-Forwarded-Encrypted: i=1; AHgh+RrBcuWt3G1HOsuhDHPKLSTcMoAnGkGNylKM8cd+1Y3CVoTr47gdVZEU9js7y3LtjtaqaSzIXOXA8mOZfQ==@vger.kernel.org X-Gm-Message-State: AFuF++kW+MaExtgD8Va1KrgokQJbqHmBOi2rnQcdXJVX16mwbLJgPJCd Qe1dTjPH2lQHcK4vGGKTIqB6uwWmT8rXCOHwmxQJzXdhpAZe7sjL751AyrlAc+GGsnAHDhE+X69 UW6trDyB+k/0NvYuWCBEiLTX7rHKTGr5SwZfvbA9XyPFOl1STWvvN0BtLI2LaXGaqcA== X-Gm-Gg: AR+sD10GaQeun3JmD1qr94hagklkdpMzdr2FqEdfHhuVLHnUUQ1PlKJtq2StyuMPv9h U1HD708+oqOhux+bFV5NDU5W/FO5PZkl+xFvcSn0EF3lXaxvkF6JfLMVlaLQyEcQkWbbpZn15cK Q9b1t5t5oPcHlPdmI4NnKPCaWqSKLpEQ4nMgLrBJ9uHPYZ9Hql9EvXCkLkPRjjVPhU1UH3zW5G6 yjjdFTqEwNTUBWbQFKGflOG3dxzyAMDpE+4xLteqmrvuNpJpM1PFG7ggtz9MaJdNYeQ9fiXqPIu uiPQmnHcPji9ctuWQWp++41td317SQG7bpsi7HevIq6Vq5Ic/SSfaBD0O4VWMpPEGDiNCpob3Va GAKjJBYQMx9VyfCmF6MwJU0kf6lF+ X-Received: by 2002:a05:6a21:7a46:b0:3d0:ba81:79b1 with SMTP id adf61e73a8af0-3d9aa9e2184mr4428626637.0.1788329356444; Tue, 01 Sep 2026 23:09:16 -0700 (PDT) X-Received: by 2002:a05:6a21:7a46:b0:3d0:ba81:79b1 with SMTP id adf61e73a8af0-3d9aa9e2184mr4428538637.0.1788329355930; Tue, 01 Sep 2026 23:09:15 -0700 (PDT) Received: from [10.218.18.193] ([202.46.22.19]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-1430ea31f1esm3257660c88.8.2026.09.01.23.09.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 01 Sep 2026 23:09:15 -0700 (PDT) Message-ID: <942f0a0a-461e-4794-a33a-9c820635eef0@oss.qualcomm.com> Date: Wed, 2 Sep 2026 11:39:09 +0530 Precedence: bulk X-Mailing-List: linux-sound@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/3] ASoC: qcom: q6apm-dai: add VMID-based SCM assignment for mDSP buffers To: Mark Brown Cc: Srinivas Kandagatla , Liam Girdwood , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jaroslav Kysela , Takashi Iwai , linux-sound@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Mohit Sharma References: <20260826-a2a-shikra-vmid-v5-v2-0-c3dc62354eee@oss.qualcomm.com> <20260826-a2a-shikra-vmid-v5-v2-2-c3dc62354eee@oss.qualcomm.com> <948de620-a482-4624-8383-6b65eb28a5e9@sirena.org.uk> Content-Language: en-US From: Ajay Kumar Nandam In-Reply-To: <948de620-a482-4624-8383-6b65eb28a5e9@sirena.org.uk> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Authority-Analysis: v=2.4 cv=F8JnsKhN c=1 sm=1 tr=0 ts=6a97bd8d cx=c_pps a=oF/VQ+ItUULfLr/lQ2/icg==:117 a=fChuTYTh2wq5r3m49p7fHw==:17 a=IkcTkHD0fZMA:10 a=VdqzKS8jKosA:10 a=s4-Qcg_JpJYA:10 a=VkNPw1HP01LnGYTKEx00:22 a=u7WPNUs3qKkmUXheDGA7:22 a=_K5XuSEh1TEqbUxoQ0s3:22 a=bKA_SWDmMBWY0RPQJBEA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=3WC7DwWrALyhR5TkjVHa:22 X-Proofpoint-GUID: sSdZwzJ3ieLmpXkDSspEQp9VxdKjxDL8 X-Proofpoint-Spam-Info: AW1haW4tMjYwOTAyMDA1MyBTYWx0ZWRfXwWE6hzTbpX9h 2+Lt2yxCMsMchRBplCdk8ejPnYPu/82a4+48fczDNqYaNUoUk+Q8RrOOCesniYm7uKjYUn+aE70 n2TnPkC458uZ7t1xzXlUQUpeM7f1ebg= X-Proofpoint-ORIG-GUID: sSdZwzJ3ieLmpXkDSspEQp9VxdKjxDL8 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwOTAyMDA1MyBTYWx0ZWRfX04kEIO6JLAE6 DdxfsFx0IHG7+x7GmqIHI7ussQmbUOw+psc/R6Y7VwvlTCr1jUpwkXFrz1NQR9YEA45gD1AXuMl l/dCY9Jg/DSnUv+y/iE9lgxEBjogn54dXsC0gdZ8rhUHGw87EtYqSK3QGN0ZLloJdmkPK+/3jzD jf/6aaC/be1IzIwiwkwPduX1QwPcDDyIbyv+tpupTM4WHIerd3JyrBZGxBrEkpahM2DizvNk7Ux CoriD3luwMgbqAw3l+Idy/p1yW3t3u9+SMnK3J8G8x7ezgXOXsdrnyUBgjxS0fIDc7WERSMS8Lk CmPbzdCongYsujfTJ4LUTcgGAvRlHw8oxeLLccUXiJ/aX9nFvHd9yH4B7b8osll/+SBKNIFBWb+ vua5Hja5ECMnU7T5o0gIuAHMoOywTj+Hio5H6CAdQ3Xo1FkwBpP93J23HzigzU4cLdTAyutXryt osp9tE6tZZ42kxCHVZw== X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1176,Hydra:6.1.134,FMLib:17.12.100.49 definitions=2026-09-01_06,2026-09-01_03,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 priorityscore=1501 spamscore=0 lowpriorityscore=0 impostorscore=0 adultscore=0 malwarescore=0 suspectscore=0 clxscore=1015 phishscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2606150000 definitions=main-2609020053 On 8/27/2026 4:22 AM, Mark Brown wrote: > On Wed, Aug 26, 2026 at 12:10:13AM +0530, Ajay Kumar Nandam wrote: >> On platforms such as Qualcomm Shikra, audio is served by the modem DSP >> (mDSP) which runs in a stage-2 protected context. Unlike ADSP targets >> where SMMU-mapped system RAM is directly accessible, the mDSP cannot >> reach the PCM buffers unless they are explicitly SCM-assigned to the >> appropriate Virtual Machine IDs (VMIDs). Without this assignment, audio >> does not function on these platforms. > >> - ret = snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV, component->dev, size); >> + if (pdata->has_reserved_mem) >> + ret = snd_pcm_set_managed_buffer_all(pcm, >> + SNDRV_DMA_TYPE_DEV, component->dev, >> + pdata->reserved_buf_size, >> + pdata->reserved_buf_size); > > Does this do the right thing if the ALSA core preallocate_dma module > param is set to 0 for some reason? I'm not clear why you would... Good catch. With preallocate_dma=0 the managed-buffer path defers allocation to stream open, but the reserved-memory carveout is a fixed-size pool that must always be mapped upfront — lazy allocation from the system page allocator would bypass the SCM-assigned region entirely. Will switch back to snd_pcm_set_fixed_buffer_all() for the reserved-memory path in v3; the carveout is fixed by nature and should not be subject to the preallocate knob. Thanks & Regards Ajay Kumar Nandam