From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (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 4950B1E7660 for ; Mon, 14 Sep 2026 01:21:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789348878; cv=none; b=LXwCjjfsPWdsbC6UiEnEahE4Lq+AE3GuhA0LKSgw7s19rgHZMS8jPWsbWejaL/wJJpp9YUuPvIF/jPfwFdpk1RUzejwA9CTzcjIE3jB0xBx7RRvttt2wpazQpBhbHRuG6hOOTFW44ZC+f7Gb3ZtrzqCliqc/Teq+7Kj9cTAwDi8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789348878; c=relaxed/simple; bh=Jo52MSARa8uRGstHX+nkOGEuELufQdjvMtbOTrNMYwo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=lC6SkJ0+k7dFMn2eJ/umKwoOg2LkJEt8GZs0pIWWYws0LQ/KtsXcHWzoTjyF0hOUDQJmaIrDllOPagxjhftHwVwYJzhFBBjv04UJ9zvRMeW2bW6vq4CI0+NoiOZJLkIKMTCcj3pjxtJRPYZjW7rJt5UPAH8rjlcYH3BuKO7nx8Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=YHfXXgW8; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b=chpAJdix; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YHfXXgW8"; dkim=pass (2048-bit key) header.d=redhat.com header.i=@redhat.com header.b="chpAJdix" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1789348876; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=hB6oGUDhB7NpBPwBSAbY4P+UYTTTI5VBvn+Ldw600iI=; b=YHfXXgW8/E69IFzH1P0NsSxa4i4g6gI7J4wBhS/zRbDVyxbr6n2ywlFk4B9erienqNCFAB LbzMxZo1GHrRd82bYXxHw6vVIiEnlZjQ6PB48l+QT+46RuefExJenVD032uElA2AqhGGVq 0mHc99zuIopUk5KCvhnidbmjlzTBtEY= Received: from mail-pj1-f69.google.com (mail-pj1-f69.google.com [209.85.216.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-615-m2n53Mz1Oo2U91vXCWZ3WQ-1; Sun, 13 Sep 2026 21:21:15 -0400 X-MC-Unique: m2n53Mz1Oo2U91vXCWZ3WQ-1 X-Mimecast-MFC-AGG-ID: m2n53Mz1Oo2U91vXCWZ3WQ_1789348874 Received: by mail-pj1-f69.google.com with SMTP id 98e67ed59e1d1-39de1ee0073so463760a91.1 for ; Sun, 13 Sep 2026 18:21:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=google; t=1789348874; x=1789953674; 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=hB6oGUDhB7NpBPwBSAbY4P+UYTTTI5VBvn+Ldw600iI=; b=chpAJdixC4uVrly4nQeYE71H/DbgTHFb/DoLoaynQURaKJMn/7+/ZT9URUcCBNjzsC FVz+G7FSNs6PiaA/fjWPBcGfGjyoui/Z7j3wxv9AQ/gjkcyXWiegx8vp/+Iaad3DLAu/ DxI0b1E8+R7M8HSTZykozNKcNMNjCYIMKVfiK/DCxJNahe8zr7qmKBp/ut85C1rDlQ+l Fu0CIDzaaodNzPz7nhj+qkPqjg7SVDEs9xXqznxmWypnEacCtXCOo4RmQj7JQfY3+c7e DxDFUVu82U8Tp9fY7xUEiH94fB3hH3Zi+AlF6LGTCSzBmjmR8hjwi5+dmNnCG/b745UA yFCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1789348874; x=1789953674; 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=hB6oGUDhB7NpBPwBSAbY4P+UYTTTI5VBvn+Ldw600iI=; b=IwOfyzUN0s+laEjWdhUK5XCrJOzz7c31XzBmCaFKzJGxWaCn4H5nhouEJaz5EFgS56 rfLdMm2hw1NoyvxH9Pnlv897oLujusLzrNjaF9rM3rtj5lPxbW02KCZVa07XRLYHZ0zW lT4wUmLIZuU3EPP2mn+4nS2TPQIpU82FRcaOHfwQ3ZdyMBpMH8gid0WXE5NFbsmauHpf YrxQ/V9A09WulWfRVVZlzAogGdr9RfRr6Un4UvjQPLkmsfNAqS2AucfXaXi8hOLt0ItE g3Hl2u9Ib7Kd1TzBIjQKjXKNJZQUSACHNzlCspcIHMd1CgE3FWudGebRWgXJsV5vvs0Q QOeQ== X-Forwarded-Encrypted: i=1; AKwUvByOuPWXQtn/avu+wjoERpkm1BaAire51GUBNjpn1x582wPDgBfGHr1m0xFvk0OaSUnGgrKZUbUCInliNlI=@vger.kernel.org X-Gm-Message-State: AFuF++lqPW7P83+Fw429Lwpd58HGx6rUrUmzgOy6OOkf+bu2PJm5GOcI WF+FHQGQfoN7hllepQJZaitzBehGNPzOP+nxa2z0mEiYYY5EQoYrb8YZYErZ3E+3I41jFiSlTUm ik7mZQiK5WjdKbzx1dpjXyYcSNCWxaqpirXD0KwIn+fQFSd48XFhCK88Wqw+MqBzCvg== X-Gm-Gg: AYBFou0kcJbDaZ4Vaw8eUcs93xYOAvA/TMP667DtvFVX2llK6pxwOUnR05f4Um7srX9 mrS3aeZhjW3Yf/g1eFdV+rkqma3tku69EdO9bDXNvZREnZBtI3iAxGC8nR+AuB6pnLrT58wNOsQ LbkgHmiVzpnRDEzOwaQJ8ge93MiONc1fJTNfYPHvO8UcKPdUZuMMRjEWtvmaTiy9R8mSESswnWC 2j5IhxlsWPwtpyhEbHmMO67WXp01phq1JDN1vqFUyA+OD6jvBsTBu+vSapYCMnVrf2XQQxvHI8l yLEcAmqaKnK3PrQoDrod+6pDxzhlPDFKkCgllbiWnMnsZGvf3kP3HzxJe20yM1V/OS7srbQeKQu GoExs2JQIdCNrB0bi/jbSNyNhoBLsKgVQ6iEyQHeqjA== X-Received: by 2002:a17:90a:1041:b0:39d:edfc:26a0 with SMTP id 98e67ed59e1d1-39dedfc3adamr55100a91.1.1789348873749; Sun, 13 Sep 2026 18:21:13 -0700 (PDT) X-Received: by 2002:a17:90a:1041:b0:39d:edfc:26a0 with SMTP id 98e67ed59e1d1-39dedfc3adamr55067a91.1.1789348873263; Sun, 13 Sep 2026 18:21:13 -0700 (PDT) Received: from [192.168.68.52] (n175-34-8-244.mrk21.qld.optusnet.com.au. [175.34.8.244]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-39db090dfa5sm4045013a91.4.2026.09.13.18.21.03 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 13 Sep 2026 18:21:12 -0700 (PDT) Message-ID: <6d204c05-1338-4ee5-9ac9-5d9447e329ee@redhat.com> Date: Mon, 14 Sep 2026 11:21:01 +1000 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v18 3/7] firmware: arm_rmm: Configure the RMM with the host's page size To: Suzuki K Poulose , kvm@vger.kernel.org, kvmarm@lists.linux.dev Cc: maz@kernel.org, will@kernel.org, catalin.marinas@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, steven.price@arm.com, aneesh.kumar@kernel.org, oupton@kernel.org, joey.gouly@arm.com, tabba@google.com, yuzenghui@huawei.com, linux-coco@lists.linux.dev, gankulkarni@os.amperecomputing.com, sdonthineni@nvidia.com, alpergun@google.com, fj0570is@fujitsu.com, WeiLin.Chang@arm.com, lpieralisi@kernel.org, enju.kohei@fujitsu.com References: <20260912083611.2513845-1-suzuki.poulose@arm.com> <20260912083611.2513845-4-suzuki.poulose@arm.com> Content-Language: en-US From: Gavin Shan In-Reply-To: <20260912083611.2513845-4-suzuki.poulose@arm.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 9/12/26 6:36 PM, Suzuki K Poulose wrote: > From: Steven Price > > RMM v2.0 brings the ability to set the RMM's granule size. Check the > feature registers and configure the RMM so that it matches the host's > page size. This means that operations can be done with a granularity > equal to PAGE_SIZE. > > Reviewed-by: Suzuki K Poulose > Signed-off-by: Steven Price > Signed-off-by: Suzuki K Poulose > --- > Changes since v17: > * Move rmi_config_set() out of the header file. > * Print the error message for rmi_config_set if it fails > Changes since v15: > * Actually check the feature register for the host's page-size support. > Changes since v14: > * Move the implementation into drivers/firmware/arm_rmm. > Changes since v13: > * Moved out of KVM. > --- > drivers/firmware/arm_rmm/rmi.c | 79 ++++++++++++++++++++++++++++++++++ > 1 file changed, 79 insertions(+) > > diff --git a/drivers/firmware/arm_rmm/rmi.c b/drivers/firmware/arm_rmm/rmi.c > index 2fd538c937dca..5b0e342ce3d58 100644 > --- a/drivers/firmware/arm_rmm/rmi.c > +++ b/drivers/firmware/arm_rmm/rmi.c > @@ -35,6 +35,25 @@ static int rmi_features(unsigned long index, unsigned long *out) > return args.a0; > } > > +/** > + * rmi_rmm_config_set() - Configure the RMM > + * @cfg_ptr: PA of a struct rmm_config > + * > + * Sets configuration options on the RMM. > + * > + * Return: RMI return code > + */ > +static int rmi_rmm_config_set(unsigned long cfg_ptr) > +{ > + struct arm_smccc_1_2_regs regs = { > + SMC_RMI_RMM_CONFIG_SET, cfg_ptr, > + }; > + > + rmi_smccc_invoke(®s); > + > + return regs.a0; > +} > + The comments for rmi_rmm_config_set() can be dropped since its logic is simply enough and the code is self-explainning. Besides, I would move this right before its only caller rmi_configure(). I would suggest drop this function by combining its logics into the only caller rmi_configure(), seeing below for more details. > unsigned long rmi_feat_reg(unsigned long index) > { > if (WARN_ON(index >= RMI_FEAT_REG_COUNT)) > @@ -98,6 +117,62 @@ static int rmi_read_features(void) > return 0; > } > > +static int rmi_configure(void) > +{ > + unsigned long granule_feature; > + unsigned long granule_size; > + int ret = 0; > + struct rmm_config *config; > + > + switch (PAGE_SIZE) { > + case SZ_4K: > + granule_size = RMI_GRANULE_SIZE_4KB; > + granule_feature = RMI_FEATURE_REGISTER_1_RMI_GRAN_SZ_4KB; > + break; > + case SZ_16K: > + granule_size = RMI_GRANULE_SIZE_16KB; > + granule_feature = RMI_FEATURE_REGISTER_1_RMI_GRAN_SZ_16KB; > + break; > + case SZ_64K: > + granule_size = RMI_GRANULE_SIZE_64KB; > + granule_feature = RMI_FEATURE_REGISTER_1_RMI_GRAN_SZ_64KB; > + break; > + default: > + BUILD_BUG(); > + } > + > + if (!(rmi_feat_reg(1) & granule_feature)) { > + pr_err("RMM does not support %luKB granules\n", > + PAGE_SIZE >> 10); > + return -ENXIO; > + } > + > + config = (struct rmm_config *)get_zeroed_page(GFP_KERNEL); > + if (!config) { > + pr_err("Unable to allocate memory for RMM config\n"); > + return -ENOMEM; > + } > + > + config->rmi_granule_size = granule_size; > + > + /* > + * For now we set the tracking_region_size to 0 which is the only option > + * for 4KB PAGE_SIZE (1GB for 4KB PAGE_SIZE, 32MB/512MB for 16KB/64KB). > + * TODO: Support other tracking sizes via Kconfig option for other > + * PAGE_SIZES > + */ > + config->tracking_region_size = 0; > + > + ret = rmi_rmm_config_set(virt_to_phys(config)); > + if (ret) { > + pr_err("RMM config set failed (%d)\n", ret); > + ret = -EINVAL; > + } > + I would suggest to drop rmi_rmm_config_set() by combining its logic to rmi_configure(). struct arm_smccc_1_2_regs args = { SMC_RMI_RMM_CONFIG_SET }; args.a1 = virt_to_phys(config); rmi_smccc_invoke(&args); if (args.a0 != RMI_SUCCESS) { pr_err("RMM config set failed (%ld)\n", args.a0); ret = -EINVAL; } > + free_page((unsigned long)config); > + return ret; > +} > + > static int __init arm64_init_rmi(void) > { > int ret; > @@ -111,6 +186,10 @@ static int __init arm64_init_rmi(void) > if (ret) > return ret; > > + ret = rmi_configure(); > + if (ret) > + return ret; > + > return 0; > } > Thanks, Gavin