From patchwork Tue Dec 21 17:00:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 1571792 X-Patchwork-Delegate: tudor.ambarus@gmail.com Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=1CS3no7+; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4JJN6Q1k9Qz9s0r for ; Wed, 22 Dec 2021 04:02:06 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Z4NgDIqRKEo2+dKCgIrbM4bKf0UXvniGNxS0ByjzjbY=; b=1CS3no7+cQq0WU iIf+Lu72+9PzGUVHH/dAz1TUc10LP/p3AmX9qPfRIz1mCWdCIu8qKF0Rk09zcJSiN//IPFxC09zkK 1NB13wmRRoFqy6RsriGOR09BZqFc8Vqwt2FVfbkawxVXnkQ/lFbVp/kk6JiMUuKaPx0d5WoAKPGGQ 7LxCDg74G6/X/99izZqa3ijW6LH7c0HWZswIXq7VdqM0xMzZ6WhcpKVhyuovqrF8aFcaHE5i0CpLb 0SnmIY9bhnOSUxGv5eMNiQALcfjnXvnJ/4iYqHFUyRX8Rja8nYUd3z/gCK5+u+BQOdRaM/hEDQLiF JIDQQ2EB3HOkj8zFJ5Xw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mziVh-007er4-Rc; Tue, 21 Dec 2021 17:01:09 +0000 Received: from relay1-d.mail.gandi.net ([217.70.183.193]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mziVf-007epN-DJ for linux-mtd@lists.infradead.org; Tue, 21 Dec 2021 17:01:09 +0000 Received: (Authenticated sender: miquel.raynal@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id 908D2240003; Tue, 21 Dec 2021 17:01:03 +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 , Rob Herring Subject: [PATCH v5 1/3] dt-bindings: mtd: spi-nor: Allow two CS per device Date: Tue, 21 Dec 2021 18:00:56 +0100 Message-Id: <20211221170058.18333-2-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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211221_090107_617709_B23047F9 X-CRM114-Status: GOOD ( 13.04 ) X-Spam-Score: -0.7 (/) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: The Xilinx QSPI controller has two advanced modes which allow the controller to behave differently and consider two flashes as one single storage. One of these two modes is quite complex to support from a binding point of view and is the dual parallel memories. In this mode, each byte of data is stored in both devices: the even bits in one, the [...] Content analysis details: (-0.7 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at https://www.dnswl.org/, low trust [217.70.183.193 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 RCVD_IN_MSPIKE_H3 RBL: Good reputation (+3) [217.70.183.193 listed in wl.mailspike.net] 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 0.0 RCVD_IN_MSPIKE_WL Mailspike good senders X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-mtd" Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org The Xilinx QSPI controller has two advanced modes which allow the controller to behave differently and consider two flashes as one single storage. One of these two modes is quite complex to support from a binding point of view and is the dual parallel memories. In this mode, each byte of data is stored in both devices: the even bits in one, the odd bits in the other. The split is automatically handled by the QSPI controller and is transparent for the user. The other mode is simpler to support, it is called dual stacked memories. The controller shares the same SPI bus but each of the devices contain half of the data. Once in this mode, the controller does not follow CS requests but instead internally wires the two CS levels with the value of the most significant address bit. Supporting these two modes will involve core changes which include the possibility of providing two CS for a single SPI device Signed-off-by: Miquel Raynal Acked-by: Rob Herring Reviewed-by: Pratyush Yadav --- Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml index 39421f7233e4..4abfb4cfc157 100644 --- a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml +++ b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml @@ -47,7 +47,8 @@ properties: identified by the JEDEC READ ID opcode (0x9F). reg: - maxItems: 1 + minItems: 1 + maxItems: 2 spi-max-frequency: true spi-rx-bus-width: true