From patchwork Tue Dec 21 17:00:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 12690157 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7A270C433EF for ; Tue, 21 Dec 2021 17:01:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240110AbhLURBK (ORCPT ); Tue, 21 Dec 2021 12:01:10 -0500 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:55447 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240103AbhLURBI (ORCPT ); Tue, 21 Dec 2021 12:01:08 -0500 Received: (Authenticated sender: miquel.raynal@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id 91CBB240008; Tue, 21 Dec 2021 17:01:05 +0000 (UTC) From: Miquel Raynal To: Rob Herring , Cc: Michal Simek , Thomas Petazzoni , Mark Brown , , Richard Weinberger , Vignesh Raghavendra , Tudor Ambarus , Pratyush Yadav , Michael Walle , , Miquel Raynal Subject: [PATCH v5 2/3] spi: dt-bindings: Describe stacked/parallel memories modes Date: Tue, 21 Dec 2021 18:00:57 +0100 Message-Id: <20211221170058.18333-3-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20211221170058.18333-1-miquel.raynal@bootlin.com> References: <20211221170058.18333-1-miquel.raynal@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Describe two new memories modes: - A stacked mode when the bus is common but the address space extended with an additinals wires. - A parallel mode with parallel busses accessing parallel flashes where the data is spread. Signed-off-by: Miquel Raynal Acked-by: Pratyush Yadav --- Hello Rob, I know the below does not pass the tests (at least the example patch 3 does not pass) but I believe the issue is probably on the tooling side because the exact same thing with uing32-array instead is accepted. The problem comes from the minItems/maxItems lines. Without them, this is okay. The maxItems btw matches the "good enough value for now" idea. The errors I get are: $ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/spi/spi-controller.yaml LINT Documentation/devicetree/bindings CHKDT Documentation/devicetree/bindings/processed-schema-examples.json SCHEMA Documentation/devicetree/bindings/processed-schema-examples.json DTEX Documentation/devicetree/bindings/spi/spi-controller.example.dts DTC Documentation/devicetree/bindings/spi/spi-controller.example.dt.yaml CHECK Documentation/devicetree/bindings/spi/spi-controller.example.dt.yaml /src/Documentation/devicetree/bindings/spi/spi-controller.example.dt.yaml: spi@80010000: flash@2:stacked-memories: [[268435456, 268435456]] is too short From schema: /src/Documentation/devicetree/bindings/spi/spi-controller.yaml /src/Documentation/devicetree/bindings/spi/spi-controller.example.dt.yaml: spi@80010000: flash@2:stacked-memories: [[268435456, 268435456]] is too short From schema: /src/Documentation/devicetree/bindings/spi/mxs-spi.yaml /src/Documentation/devicetree/bindings/spi/spi-controller.example.dt.yaml: spi@80010000: Unevaluated properties are not allowed ('#address-cells', '#size-cells', 'display@0', 'sensor@1', 'flash@2' were unexpected) From schema: /src/Documentation/devicetree/bindings/spi/mxs-spi.yaml /src/Documentation/devicetree/bindings/spi/spi-controller.example.dt.yaml: flash@2: stacked-memories: [[268435456, 268435456]] is too short From schema: /src/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml .../bindings/spi/spi-peripheral-props.yaml | 25 +++++++++++++++++++ 1 file changed, 25 insertions(+) diff --git a/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml b/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml index 5dd209206e88..fedb7ae98ff6 100644 --- a/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml +++ b/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml @@ -82,6 +82,31 @@ properties: description: Delay, in microseconds, after a write transfer. + stacked-memories: + description: Several SPI memories can be wired in stacked mode. + This basically means that either a device features several chip + selects, or that different devices must be seen as a single + bigger chip. This basically doubles (or more) the total address + space with only a single additional wire, while still needing + to repeat the commands when crossing a chip boundary. The size of + each chip should be provided as members of the array. + $ref: /schemas/types.yaml#/definitions/uint64-array + minItems: 2 + maxItems: 4 + + parallel-memories: + description: Several SPI memories can be wired in parallel mode. + The devices are physically on a different buses but will always + act synchronously as each data word is spread across the + different memories (eg. even bits are stored in one memory, odd + bits in the other). This basically doubles the address space and + the throughput while greatly complexifying the wiring because as + many busses as devices must be wired. The size of each chip should + be provided as members of the array. + $ref: /schemas/types.yaml#/definitions/uint64-array + minItems: 2 + maxItems: 4 + # The controller specific properties go here. allOf: - $ref: cdns,qspi-nor-peripheral-props.yaml#