From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6556EC3DA4A for ; Fri, 16 Aug 2024 17:40:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=qd+nepfzAVl/w9Hny3aM260SBA3kiMeVt97gGRIgVIY=; b=38WzgAEZorLCfOt/Ep7IrpcIwx fN5H0Oga5ANJCQ0/J1ylJJXz1nLOPqpMvPUr8HgIHKmqEWjeu2UdmV3ht8wR8+SlIPs4dzCuehgZQ W5A1DCqZl3eKdpwh5uwZ0CA95j7fxz7sMq6YrLBhBwrJ3jQYTFiSgHGCB5ZzhnL3a9V7U2MxOJRT4 F8QdXZbmYWonw4AdR0ySq5VCNtcWKbcXynxGGQp+YwU76O4ILy1+RSN3B2lLMUhVYNGlDwA4B1d1Y KnR8hp2Nm35+RwxC5T4Qsc1pFDU/eIXBUJq9Pvkc6h/sEDyfIr6zGc168on1xbpok4rpSsbA1PaeP 09I4aPzg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sf0w8-0000000DjND-0ap8; Fri, 16 Aug 2024 17:40:28 +0000 Received: from mail-oa1-x34.google.com ([2001:4860:4864:20::34]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sf0vS-0000000DjIg-3rsX for linux-arm-kernel@lists.infradead.org; Fri, 16 Aug 2024 17:39:48 +0000 Received: by mail-oa1-x34.google.com with SMTP id 586e51a60fabf-2642cfb2f6aso1704174fac.2 for ; Fri, 16 Aug 2024 10:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; t=1723829985; x=1724434785; darn=lists.infradead.org; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:from:to:cc:subject:date:message-id:reply-to; bh=qd+nepfzAVl/w9Hny3aM260SBA3kiMeVt97gGRIgVIY=; b=OdtbSUPtbcNr6Pjm7MQ4GdGl4HJOPOsFHXUcsgTUWZez+cpG1MpLllo4FIBpmM5IPS M5vNtciTJSn2iQSKBEMVxfm0nSTlfC9b5gY1Zb75eO0dyrRIgA7NQ9o9t+XQuCvBLmi9 vDMe92YepnHK64PMtzgDCK+qQXpANlPemQaEo= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723829985; x=1724434785; h=content-transfer-encoding:in-reply-to:autocrypt:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=qd+nepfzAVl/w9Hny3aM260SBA3kiMeVt97gGRIgVIY=; b=QFLaJ7w/YKNZ/arXF+lb5QzGP3Oz40+f5seysyK1v9w0nyZeb9lX01w3aXCVqaVMhA /bLz8WQvo4S7LHZTL+wUUF9nynMe82bTLJnZ5xKRSDtqO9BUkb3YxRvYOL0d0JbfSZHd aiZN0/Dl5t3g9oe3C/Pg2Koi72D/48lVhPwpAW/lpCMla9qWCQU2imaZSGqTCIlVMM1O iTH1Epvhw3bUz7LuasXhiHwmcZD8vGEk9GcQi+Z1VZKHOab2v/Jkh2/0wASKhLR1n8wb feyeeneUKfg2cBJQHeDCfD/j2EC7fnIRd98s4Knrvk8315xLKdVIBR73S7z5v1qAk9tJ 4ZEA== X-Forwarded-Encrypted: i=1; AJvYcCW+GQs22RO5GnBnU21XJxhGzcGanNQUVgrW4hd0l0apoFYREHvUDJFGR35qraT+lQgCWQdds0gbde5CBnMuVXJtmx5qVdzSuXcZwuE5i5fX7o+R2Rc= X-Gm-Message-State: AOJu0Yw3XjwLz/IkcXxe8WM8KOWrFD9f9Wsx/7Wh5TyxDs30GAGXozMZ 4kwxCLXZi6hnaBfdM8MDp/0nhvgddB10sm1K1kRnBQrQtHMEhLLIzlQ+LpqsTw== X-Google-Smtp-Source: AGHT+IF2ic1q163w/nEDiGmEdTz4MMQVMfCwPMi9rRTKxKvjMahEdZCXO0bmoMzW4Dwi74pqiDuzGw== X-Received: by 2002:a05:6871:3422:b0:270:1d05:1add with SMTP id 586e51a60fabf-2701d05980cmr4298850fac.16.1723829984594; Fri, 16 Aug 2024 10:39:44 -0700 (PDT) Received: from [10.67.48.245] ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id 41be03b00d2f7-7c6b61dc929sm3265530a12.40.2024.08.16.10.39.42 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Aug 2024 10:39:43 -0700 (PDT) Message-ID: <345aca0f-12f0-4a66-a760-3b8524fda7fe@broadcom.com> Date: Fri, 16 Aug 2024 10:39:42 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 2/2] firmware: arm_scmi: Support 'reg-io-width' property for shared memory To: Cristian Marussi Cc: linux-kernel@vger.kernel.org, Rob Herring , Krzysztof Kozlowski , Conor Dooley , Sudeep Holla , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , "open list:SYSTEM CONTROL & POWER/MANAGEMENT INTERFACE" , "moderated list:SYSTEM CONTROL & POWER/MANAGEMENT INTERFACE" , justin.chen@broadcom.com, opendmb@gmail.com, kapil.hali@broadcom.com, bcm-kernel-feedback-list@broadcom.com References: <20240813180747.1439034-1-florian.fainelli@broadcom.com> <20240813180747.1439034-3-florian.fainelli@broadcom.com> Content-Language: en-US From: Florian Fainelli Autocrypt: addr=florian.fainelli@broadcom.com; keydata= xsBNBFPAG8ABCAC3EO02urEwipgbUNJ1r6oI2Vr/+uE389lSEShN2PmL3MVnzhViSAtrYxeT M0Txqn1tOWoIc4QUl6Ggqf5KP6FoRkCrgMMTnUAINsINYXK+3OLe7HjP10h2jDRX4Ajs4Ghs JrZOBru6rH0YrgAhr6O5gG7NE1jhly+EsOa2MpwOiXO4DE/YKZGuVe6Bh87WqmILs9KvnNrQ PcycQnYKTVpqE95d4M824M5cuRB6D1GrYovCsjA9uxo22kPdOoQRAu5gBBn3AdtALFyQj9DQ KQuc39/i/Kt6XLZ/RsBc6qLs+p+JnEuPJngTSfWvzGjpx0nkwCMi4yBb+xk7Hki4kEslABEB AAHNMEZsb3JpYW4gRmFpbmVsbGkgPGZsb3JpYW4uZmFpbmVsbGlAYnJvYWRjb20uY29tPsLB IQQQAQgAywUCZWl41AUJI+Jo+hcKAAG/SMv+fS3xUQWa0NryPuoRGjsA3SAUAAAAAAAWAAFr ZXktdXNhZ2UtbWFza0BwZ3AuY29tjDAUgAAAAAAgAAdwcmVmZXJyZWQtZW1haWwtZW5jb2Rp bmdAcGdwLmNvbXBncG1pbWUICwkIBwMCAQoFF4AAAAAZGGxkYXA6Ly9rZXlzLmJyb2FkY29t Lm5ldAUbAwAAAAMWAgEFHgEAAAAEFQgJChYhBNXZKpfnkVze1+R8aIExtcQpvGagAAoJEIEx tcQpvGagWPEH/2l0DNr9QkTwJUxOoP9wgHfmVhqc0ZlDsBFv91I3BbhGKI5UATbipKNqG13Z TsBrJHcrnCqnTRS+8n9/myOF0ng2A4YT0EJnayzHugXm+hrkO5O9UEPJ8a+0553VqyoFhHqA zjxj8fUu1px5cbb4R9G4UAySqyeLLeqnYLCKb4+GklGSBGsLMYvLmIDNYlkhMdnnzsSUAS61 WJYW6jjnzMwuKJ0ZHv7xZvSHyhIsFRiYiEs44kiYjbUUMcXor/uLEuTIazGrE3MahuGdjpT2 IOjoMiTsbMc0yfhHp6G/2E769oDXMVxCCbMVpA+LUtVIQEA+8Zr6mX0Yk4nDS7OiBlvOwE0E U8AbwQEIAKxr71oqe+0+MYCc7WafWEcpQHFUwvYLcdBoOnmJPxDwDRpvU5LhqSPvk/yJdh9k 4xUDQu3rm1qIW2I9Puk5n/Jz/lZsqGw8T13DKyu8eMcvaA/irm9lX9El27DPHy/0qsxmxVmU pu9y9S+BmaMb2CM9IuyxMWEl9ruWFS2jAWh/R8CrdnL6+zLk60R7XGzmSJqF09vYNlJ6Bdbs MWDXkYWWP5Ub1ZJGNJQ4qT7g8IN0qXxzLQsmz6tbgLMEHYBGx80bBF8AkdThd6SLhreCN7Uh IR/5NXGqotAZao2xlDpJLuOMQtoH9WVNuuxQQZHVd8if+yp6yRJ5DAmIUt5CCPcAEQEAAcLB gQQYAQIBKwUCU8AbwgUbDAAAAMBdIAQZAQgABgUCU8AbwQAKCRCTYAaomC8PVQ0VCACWk3n+ obFABEp5Rg6Qvspi9kWXcwCcfZV41OIYWhXMoc57ssjCand5noZi8bKg0bxw4qsg+9cNgZ3P N/DFWcNKcAT3Z2/4fTnJqdJS//YcEhlr8uGs+ZWFcqAPbteFCM4dGDRruo69IrHfyyQGx16s CcFlrN8vD066RKevFepb/ml7eYEdN5SRALyEdQMKeCSf3mectdoECEqdF/MWpfWIYQ1hEfdm C2Kztm+h3Nkt9ZQLqc3wsPJZmbD9T0c9Rphfypgw/SfTf2/CHoYVkKqwUIzI59itl5Lze+R5 wDByhWHx2Ud2R7SudmT9XK1e0x7W7a5z11Q6vrzuED5nQvkhAAoJEIExtcQpvGagugcIAJd5 EYe6KM6Y6RvI6TvHp+QgbU5dxvjqSiSvam0Ms3QrLidCtantcGT2Wz/2PlbZqkoJxMQc40rb fXa4xQSvJYj0GWpadrDJUvUu3LEsunDCxdWrmbmwGRKqZraV2oG7YEddmDqOe0Xm/NxeSobc MIlnaE6V0U8f5zNHB7Y46yJjjYT/Ds1TJo3pvwevDWPvv6rdBeV07D9s43frUS6xYd1uFxHC 7dZYWJjZmyUf5evr1W1gCgwLXG0PEi9n3qmz1lelQ8lSocmvxBKtMbX/OKhAfuP/iIwnTsww 95A2SaPiQZA51NywV8OFgsN0ITl2PlZ4Tp9hHERDe6nQCsNI/Us= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240816_103947_178741_2AB40593 X-CRM114-Status: GOOD ( 28.66 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 8/16/24 10:02, Cristian Marussi wrote: > On Tue, Aug 13, 2024 at 11:07:47AM -0700, Florian Fainelli wrote: >> Some shared memory areas might only support a certain access width, >> such as 32-bit, which memcpy_{from,to}_io() does not adhere to at least >> on ARM64 by making both 8-bit and 64-bit accesses to such memory. >> >> Update the shmem layer to support reading from and writing to such >> shared memory area using the specified I/O width in the Device Tree. The >> various transport layers making use of the shmem.c code are updated >> accordingly to pass the I/O accessors that they store. >> > > Hi Florian, > > I gave it ago at this on a JUNO regarding the mailbox/shmem transport > without any issue. I'll have a go later on an OPTEE/shmem scenario too. > > This looks fundamentally good to me, since you moved all ops setup at > setup time and you keep the pointers per-channel instead of global... Thanks! > > A few remarks down below. > >> Signed-off-by: Florian Fainelli [snip] > > ... I may be missing a lot here...bear with me...so... > > ... AFAIU, as suggested by Peng, you moved away from iowrite##s and ioread##s > in favour of __raw_write/read##w so as to avoid the implicit barriers on each > loop iteration...(I suppose..) > > ...but should we place some sort of final io barrier (similarly to iowrite) > at the end of the loop ? There is no leading or trailing barrier with the ARM64 memcpy_{to,from}io routines which is why this was carried forward as-is. There is an implicit barrier with the iowrite32() in the tx_prepare(), so I suppose we are somewhat safe on that part. Likewise with the fetch_response()/fetch_notification() we have an implicit barrier within the ioread32() and then there is a data dependency since we ought to be consuming the response/notification. For ARM 32-bit the implementation uses readb()/writeb() which does include barriers. > >> +static inline void shmem_memcpy_toio##s(volatile void __iomem *to, \ >> + const void *from, \ >> + size_t count) \ >> +{ \ >> + while (count) { \ >> + __raw_write##w(*(u##s *)from, to); \ >> + from += amt; \ >> + to += amt; \ >> + count -= amt; \ >> + } \ >> +} > > ...same concern here > >> +static struct scmi_shmem_io_ops shmem_io_ops##s = { \ >> + .fromio = shmem_memcpy_fromio##s, \ >> + .toio = shmem_memcpy_toio##s, \ >> +}; The macro might be a tad too much given that we only support one width, in case we needed to add a specific size in the future we could use a macro again I suppose, for now, just inlined the implementation for the 4-byte / 32-bit size. >> + > > There are a bunch of warn/errs from checkpatch --strict, beside the volatile > here and on the previous typedefs, also about args reuse and trailing semicolon > in these macros... I don't think we can silence the volatile ones, checkpatch --strict did not complain about the typedefs in my case, what did it look like in yours? -- Florian