From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 145D52E2DD4; Thu, 14 Aug 2025 07:48:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755157700; cv=none; b=RzYnW0F2/0xX4ifPvy/P68YKm/oqVLRA8gr5v7+HcbE3vLk0iKCYb6AKoALTMjSm1SX8AmxB7jGYgGfVy5DjBdo43DB4d4ajfFZmx2XBaBaINKCd6siL9U39DGBzWPG8y4Vzih/0spgmsN/RyRf7J/e7qU9ShearZyjVgUchcn8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755157700; c=relaxed/simple; bh=4I2LLiyJ9DPd4hAV9M6f+f6szjy4RI1GEIyPYnnsRJ0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sbzjEuzTr/4X1p29SzjaTGIJW1/7NOS4NadpDWZ2Yfh1WeVp/JyYT0Sr5qq+CuRtr4r7IUuraewYYzHpUNoJnpMuDwt+XeiBGuS/uStI5RZn2UuYvj7zfLuWNjtZo8/2A1YGRU/pHvRZHMO++TUoARAqJLG8wbfsXqto7BFDlUA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=c6a8KH03; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="c6a8KH03" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 21298C4CEEF; Thu, 14 Aug 2025 07:48:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755157697; bh=4I2LLiyJ9DPd4hAV9M6f+f6szjy4RI1GEIyPYnnsRJ0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=c6a8KH035/R1tJ68b8GYHhGdk+3gApxdXHhos1ntBpqbYonicYG5hHoR2CqoCnTV5 CS6UtxDDg9kSJW+ANZ3LCvNpuRWW3GXjhBQnYkJ8x4RNYOoewVS/SyXnqDUoxAKyDm CFjORTPsTGzeDpbC6YfBqVocChKstD3DoxwnCCk7mKTjloqI2H1t3RNBLTTLn563wd aQhsLzPRVNAtQkKXxAU91kyczgNaetcev249Zfy6/XM7nIJeUP8x6QXwO7zuWEMMjS Aosyecpk24gzRfMuVivOd4CyVxE/ChxuRmJ1p+aRuboJ2oiBTvl4d3DwgSt2gRUG7/ B5ML3XIgIOFiw== Message-ID: Date: Thu, 14 Aug 2025 09:48:12 +0200 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: [RFC PATCH 1/4] dt-bindings: mailbox: thead,th1520-mbox: retrofit for other mailboxes To: Icenowy Zheng , Drew Fustini , Guo Ren , Fu Wei , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jassi Brar , Michal Wilczynski Cc: Han Gao , Inochi Amaoto , Yao Zi , linux-riscv@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20250814070757.2267325-1-uwu@icenowy.me> <20250814070757.2267325-2-uwu@icenowy.me> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGVBBMBCgA/AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJoF1BKBQkWlnSaAAoJEBuTQ307 QWKbHukP/3t4tRp/bvDnxJfmNdNVn0gv9ep3L39IntPalBFwRKytqeQkzAju0whYWg+R/rwp +r2I1Fzwt7+PTjsnMFlh1AZxGDmP5MFkzVsMnfX1lGiXhYSOMP97XL6R1QSXxaWOpGNCDaUl ajorB0lJDcC0q3xAdwzRConxYVhlgmTrRiD8oLlSCD5baEAt5Zw17UTNDnDGmZQKR0fqLpWy 786Lm5OScb7DjEgcA2PRm17st4UQ1kF0rQHokVaotxRM74PPDB8bCsunlghJl1DRK9s1aSuN hL1Pv9VD8b4dFNvCo7b4hfAANPU67W40AaaGZ3UAfmw+1MYyo4QuAZGKzaP2ukbdCD/DYnqi tJy88XqWtyb4UQWKNoQqGKzlYXdKsldYqrLHGoMvj1UN9XcRtXHST/IaLn72o7j7/h/Ac5EL 8lSUVIG4TYn59NyxxAXa07Wi6zjVL1U11fTnFmE29ALYQEXKBI3KUO1A3p4sQWzU7uRmbuxn naUmm8RbpMcOfa9JjlXCLmQ5IP7Rr5tYZUCkZz08LIfF8UMXwH7OOEX87Y++EkAB+pzKZNNd hwoXulTAgjSy+OiaLtuCys9VdXLZ3Zy314azaCU3BoWgaMV0eAW/+gprWMXQM1lrlzvwlD/k whyy9wGf0AEPpLssLVt9VVxNjo6BIkt6d1pMg6mHsUEVzsFNBFVDXDQBEADNkrQYSREUL4D3 Gws46JEoZ9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLue MNsWLJBvBaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6ei OMheesVS5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wA GldWsRxbf3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA 6z6lBZn0WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9 YegxWKvXXHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt 91pFzBSOIpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gU BLHFTg2hYnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/ JoFzZ4B0p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu 4vXVFBYIGmpyNPYzRm0QPwARAQABwsF8BBgBCgAmAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtB YpsFAmgXUF8FCRaWWyoACgkQG5NDfTtBYptO0w//dlXJs5/42hAXKsk+PDg3wyEFb4NpyA1v qmx7SfAzk9Hf6lWwU1O6AbqNMbh6PjEwadKUk1m04S7EjdQLsj/MBSgoQtCT3MDmWUUtHZd5 RYIPnPq3WVB47GtuO6/u375tsxhtf7vt95QSYJwCB+ZUgo4T+FV4hquZ4AsRkbgavtIzQisg Dgv76tnEv3YHV8Jn9mi/Bu0FURF+5kpdMfgo1sq6RXNQ//TVf8yFgRtTUdXxW/qHjlYURrm2 H4kutobVEIxiyu6m05q3e9eZB/TaMMNVORx+1kM3j7f0rwtEYUFzY1ygQfpcMDPl7pRYoJjB dSsm0ZuzDaCwaxg2t8hqQJBzJCezTOIkjHUsWAK+tEbU4Z4SnNpCyM3fBqsgYdJxjyC/tWVT AQ18NRLtPw7tK1rdcwCl0GFQHwSwk5pDpz1NH40e6lU+NcXSeiqkDDRkHlftKPV/dV+lQXiu jWt87ecuHlpL3uuQ0ZZNWqHgZoQLXoqC2ZV5KrtKWb/jyiFX/sxSrodALf0zf+tfHv0FZWT2 zHjUqd0t4njD/UOsuIMOQn4Ig0SdivYPfZukb5cdasKJukG1NOpbW7yRNivaCnfZz6dTawXw XRIV/KDsHQiyVxKvN73bThKhONkcX2LWuD928tAR6XMM2G5ovxLe09vuOzzfTWQDsm++9UKF a/A= In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 14/08/2025 09:34, Icenowy Zheng wrote: > 在 2025-08-14星期四的 09:18 +0200，Krzysztof Kozlowski写道： >> On 14/08/2025 09:07, Icenowy Zheng wrote: >>> The current binding of thead,th1520-mbox can only apply to the >>> C910T >>> mailbox (which has an ID of 0). >>> >>> Because of the weird mailbox register mapping practice for world >>> seperation on TH1520, the binding needs some reword, in addition to >>> add >>> a property for mailbox ID, to describe other mailboxes. >>> >>> Update the binding, in order to make it suitable to describe other >> >> But I do not see any new device being added. > > See PATCH 3/4 in this patchset. > > Or do you mean I need to add new compatibles as I said below? I don't know... you say there are some other mailboxes (I understand as mailbox controllers) but I don't see anything being added here. > >> >>> mailboxes. The example is also updated, with an addition of >>> mbox_c910t >>> label to show that the example describes this specfiic mailbox, >>> mailbox >>> ID added and the register window sizes updated to the values from >>> the >>> manual (previously the remote-icu0 register windows is declared to >>> be >>> overly small that it would never work). >>> >>> Signed-off-by: Icenowy Zheng >>> --- >>>  .../bindings/mailbox/thead,th1520-mbox.yaml   | 49 ++++++++++++++- >>> ---- >>>  1 file changed, 36 insertions(+), 13 deletions(-) >>> >>> diff --git >>> a/Documentation/devicetree/bindings/mailbox/thead,th1520-mbox.yaml >>> b/Documentation/devicetree/bindings/mailbox/thead,th1520-mbox.yaml >>> index 0971fb97896ef..5a24d2e8a6a8c 100644 >>> --- a/Documentation/devicetree/bindings/mailbox/thead,th1520- >>> mbox.yaml >>> +++ b/Documentation/devicetree/bindings/mailbox/thead,th1520- >>> mbox.yaml >>> @@ -12,6 +12,17 @@ description: >>>    through mailbox channels. It also allows one core to signal >>> another processor >>>    using interrupts via the Interrupt Controller Unit (ICU). >>>   >>> +  The SoC is divided to two worlds, REE and TEE, although it's >>> currently unknown >>> +  how to enable the seperation between worlds so the seperation >>> does not exist >>> +  yet. However each mailbox is assigned to a certain world, and >>> register windows >>> +  for mailboxes are assigned to different worlds too. In a certain >>> world's >>> +  register windows for mailboxes, only mailboxes assigned to this >>> world will >>> +  have the local ICU part mapped (in addition to the remote ICU >>> part of the >>> +  other same-world mailbox), and mailboxes assigned to the other >>> world have >>> +  only the coressponding remote ICU part mapped to this world. Two >>> mailboxes >>> +  (C910T and E902) are assigned to the TEE world and two mailboxes >>> (C906 and >>> +  C910R) are assigned to the REE world. >>> + >>>  maintainers: >>>    - Michal Wilczynski >>>   >>> @@ -22,9 +33,9 @@ properties: >>>    clocks: >>>      items: >>>        - description: Clock for the local mailbox >>> -      - description: Clock for remote ICU 0 >>> -      - description: Clock for remote ICU 1 >>> -      - description: Clock for remote ICU 2 >>> +      - description: Clock for the other mailbox in the same world >>> +      - description: Clock for the first mailbox in the other >>> world >>> +      - description: Clock for the second mailbox in the other >>> world >>>   >>>    clock-names: >>>      items: >>> @@ -35,10 +46,14 @@ properties: >>>   >>>    reg: >>>      items: >>> -      - description: Mailbox local base address >>> -      - description: Remote ICU 0 base address >>> -      - description: Remote ICU 1 base address >>> -      - description: Remote ICU 2 base address >>> +      - description: Base address of this specific mailbox >>> +      - description: Base address of the other mailbox in the same >>> world >>> +      - description: >>> +          Base address of the register window in this world >>> corresponding to the >>> +          first other-world mailbox. >>> +      - description: >>> +          Base address of the register window in this world >>> corresponding to the >>> +          second other-world mailbox. >> >> This feels like ABI change. >> >>>   >>>    reg-names: >>>      items: >>> @@ -50,10 +65,17 @@ properties: >>>    interrupts: >>>      maxItems: 1 >>>   >>> +  thead,mbox-id: >>> +    $ref: /schemas/types.yaml#/definitions/uint32 >>> +    description: >>> +      The ID of this specific mailbox that this device tree node >>> describes. For >>> +      compatibility with old device trees, if missing, the ID is >>> default to 0, >>> +      the C910T mailbox. >> >> No, you cannot have instance IDs. It's even explicitly documented in >> writing bindings. > > The problem is that the mailbox cannot send to itself, so the "sending > to self" slot is redefined to other meaning. I don't know what is sending to self... > > Or should I assign different compatible strings to all 4 mailboxes > because they have different registers in the "sending to self" slot, > which have different offset because of instance ID? Commit msg is quite vague in describing hardware. It has a lot of text but no answers to questions. What are the differences? What is the hardware? if you have different programming model, then you have different compatibles, usually. Best regards, Krzysztof