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 X-Spam-Level: X-Spam-Status: No, score=-14.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 93176C433C1 for ; Tue, 23 Mar 2021 23:10:04 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 25377619CC for ; Tue, 23 Mar 2021 23:10:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 25377619CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=walle.cc Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Message-ID:References:In-Reply-To:Subject:Cc:To:From :Date:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=QsaExQtMlWKvcJ43Y6HMXkl3KC2+E53pLlcKHdqPnas=; b=hhtnNIlJdHHjdOhyxfK6aM7sJ eRqX0Qp99u/UMna1EElNC8MOdculE6+9wRjcoyzAdsW3oyovoxQNA//VeIOiKbwqVhZmZe/qRuWYb tYYQ4WcdoVpXg6LncRN79QoSigmtGOic4BRbjbql7O60DeRytCqI/PgAcZ8iEAFPEcDi3hld7PolX oe6DqDyudIknRYM2Ymt4AK0fjdhFjM8b8bqdHU7LIXjzcqwedpX6dAt5pf81GwJ1GRHYDXj4WrSpT JybeyUarGjYr2360fqZgd2lLzh4oto/gSwO0wigL0dzvQJ0+ryEsR8PCju97Sf17WnqhyeRW9w43s VaaNYL2nA==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lOq7w-00Fxmp-B4; Tue, 23 Mar 2021 23:07:56 +0000 Received: from ssl.serverraum.org ([2a01:4f8:151:8464::1:2]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lOq7p-00FxmN-2W; Tue, 23 Mar 2021 23:07:52 +0000 Received: from ssl.serverraum.org (web.serverraum.org [172.16.0.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.serverraum.org (Postfix) with ESMTPSA id 4A03B22260; Wed, 24 Mar 2021 00:07:46 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=walle.cc; s=mail2016061301; t=1616540866; 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=C8nXM32KMkKRWhGgs0N1HKDFZiCWuwPI3z2aCDDXFbk=; b=oALP9ZD3prSS6SGNrjoUUBoDtku9bM8urrR9UjVpLpWMvYdYzQlrQxw+rpSp18OjIZHxiD Hc3kdGvzwuhcgZPwbr6iSiFFO3vm1ggyge8oePN6iR+odWSc0ZPJ3YeXzVvmd26GfhJlsp QnMuE/U8E6c8gkN1dT5vk7EA9evzk0Q= MIME-Version: 1.0 Date: Wed, 24 Mar 2021 00:07:46 +0100 From: Michael Walle To: Pratyush Yadav Cc: Nishanth Menon , Tero Kristo , Rob Herring , Tudor Ambarus , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Mark Brown , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org, linux-spi@vger.kernel.org, Lokesh Vutla Subject: Re: [RFC PATCH 1/6] spi: spi-mem: Tell controller when device is ready for calibration In-Reply-To: <20210311191216.7363-2-p.yadav@ti.com> References: <20210311191216.7363-1-p.yadav@ti.com> <20210311191216.7363-2-p.yadav@ti.com> User-Agent: Roundcube Webmail/1.4.11 Message-ID: <934c8c6f7bb71729bfdaefd39c63a262@walle.cc> X-Sender: michael@walle.cc X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210323_230749_325181_35901D1A X-CRM114-Status: GOOD ( 28.44 ) 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: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Pratyush, Am 2021-03-11 20:12, schrieb Pratyush Yadav: > Some controllers like the Cadence OSPI controller need to perform a > calibration sequence to operate at high clock speeds. This calibration > should happen after the flash is fully initialized otherwise the > calibration might happen in a different SPI mode from the one the flash > is finally set to. Add a hook that can be used to tell the controller > when the flash is ready for calibration. Whether calibration is needed > depends on the controller. > > Signed-off-by: Pratyush Yadav > --- > drivers/spi/spi-mem.c | 12 ++++++++++++ > include/linux/spi/spi-mem.h | 8 ++++++++ > 2 files changed, 20 insertions(+) > > diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c > index dc713b0c3c4d..e2f05ad3f4dc 100644 > --- a/drivers/spi/spi-mem.c > +++ b/drivers/spi/spi-mem.c > @@ -464,6 +464,18 @@ int spi_mem_adjust_op_size(struct spi_mem *mem, > struct spi_mem_op *op) > } > EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size); > > +int spi_mem_do_calibration(struct spi_mem *mem, struct spi_mem_op *op) > +{ > + struct spi_controller *ctlr = mem->spi->controller; > + > + if (!ctlr->mem_ops || !ctlr->mem_ops->do_calibration) > + return -EOPNOTSUPP; > + > + ctlr->mem_ops->do_calibration(mem, op); Can't a calibration fail? > + return 0; > +} > +EXPORT_SYMBOL_GPL(spi_mem_do_calibration); > + > static ssize_t spi_mem_no_dirmap_read(struct spi_mem_dirmap_desc > *desc, > u64 offs, size_t len, void *buf) > { > diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h > index 2b65c9edc34e..97a2d280f2d0 100644 > --- a/include/linux/spi/spi-mem.h > +++ b/include/linux/spi/spi-mem.h > @@ -250,6 +250,12 @@ static inline void *spi_mem_get_drvdata(struct > spi_mem *mem) > * the currently mapped area), and the caller of > * spi_mem_dirmap_write() is responsible for calling it again in > * this case. > + * @do_calibration: perform calibration needed for high SPI clock > speed > + * operation. Should be called after the SPI memory device has > + * been completely initialized. The op passed should contain > + * a template for the read operation used for the device so > + * the controller can decide what type of calibration is > + * required for this type of read. > * > * This interface should be implemented by SPI controllers providing > an > * high-level interface to execute SPI memory operation, which is > usually the > @@ -274,6 +280,7 @@ struct spi_controller_mem_ops { > u64 offs, size_t len, void *buf); > ssize_t (*dirmap_write)(struct spi_mem_dirmap_desc *desc, > u64 offs, size_t len, const void *buf); > + void (*do_calibration)(struct spi_mem *mem, struct spi_mem_op *op); > }; > > /** > @@ -346,6 +353,7 @@ bool spi_mem_dtr_supports_op(struct spi_mem *mem, > #endif /* CONFIG_SPI_MEM */ > > int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op > *op); > +int spi_mem_do_calibration(struct spi_mem *mem, struct spi_mem_op > *op); > > bool spi_mem_supports_op(struct spi_mem *mem, > const struct spi_mem_op *op); -- -michael _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel