From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752436AbdHJAFu (ORCPT ); Wed, 9 Aug 2017 20:05:50 -0400 Received: from mail-yw0-f196.google.com ([209.85.161.196]:34412 "EHLO mail-yw0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752176AbdHJAFs (ORCPT ); Wed, 9 Aug 2017 20:05:48 -0400 Date: Wed, 9 Aug 2017 19:05:45 -0500 From: Rob Herring To: Vignesh R Cc: Marek Vasut , Cyrille Pitchen , Santosh Shilimkar , David Woodhouse , Brian Norris , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH 1/7] mtd: spi-nor: cadence-quadspi: add a delay in write sequence Message-ID: <20170810000545.hphnihd5ghugfbof@rob-hp-laptop> References: <20170801045434.8733-1-vigneshr@ti.com> <20170801045434.8733-2-vigneshr@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170801045434.8733-2-vigneshr@ti.com> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 01, 2017 at 10:24:28AM +0530, Vignesh R wrote: > As per 66AK2G02 TRM[1] SPRUHY8F section 11.15.5.3 Indirect Access > Controller programming sequence, a delay equal to couple QSPI master > clock(~5ns) is required after setting CQSPI_REG_INDIRECTWR_START bit and > writing data to the flash. Add a new compatible to handle the couple of > cycles of delay required in the indirect write sequence, since this > delay is specific to TI 66AK2G SoC. > > [1]http://www.ti.com/lit/ug/spruhy8f/spruhy8f.pdf > > Signed-off-by: Vignesh R > --- > Documentation/devicetree/bindings/mtd/cadence-quadspi.txt | 1 + > drivers/mtd/spi-nor/cadence-quadspi.c | 13 +++++++++++++ > 2 files changed, 14 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt b/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt > index f248056da24c..fdd511a83511 100644 > --- a/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt > +++ b/Documentation/devicetree/bindings/mtd/cadence-quadspi.txt > @@ -2,6 +2,7 @@ > > Required properties: > - compatible : Should be "cdns,qspi-nor". > + Should be "ti,k2g-qspi" for TI 66AK2G platform. > - reg : Contains two entries, each of which is a tuple consisting of a > physical address and length. The first entry is the address and > length of the controller register set. The second entry is the > diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c > index 53c7d8e0327a..94571590371d 100644 > --- a/drivers/mtd/spi-nor/cadence-quadspi.c > +++ b/drivers/mtd/spi-nor/cadence-quadspi.c > @@ -76,6 +76,7 @@ struct cqspi_st { > u32 fifo_depth; > u32 fifo_width; > u32 trigger_address; > + u32 wr_delay; > struct cqspi_flash_pdata f_pdata[CQSPI_MAX_CHIPSELECT]; > }; > > @@ -608,6 +609,14 @@ static int cqspi_indirect_write_execute(struct spi_nor *nor, > reinit_completion(&cqspi->transfer_complete); > writel(CQSPI_REG_INDIRECTWR_START_MASK, > reg_base + CQSPI_REG_INDIRECTWR); > + /* > + * As per 66AK2G02 TRM SPRUHY8F section 11.15.5.3 Indirect Access > + * Controller programming sequence, couple of cycles of > + * QSPI_REF_CLK delay is required for the above bit to > + * be internally synchronized by the QSPI module. Provide 5 > + * cycles of delay. > + */ > + ndelay(cqspi->wr_delay); > > while (remaining > 0) { > write_bytes = remaining > page_size ? page_size : remaining; > @@ -1213,6 +1222,9 @@ static int cqspi_probe(struct platform_device *pdev) > } > > cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk); > + if (of_device_is_compatible(dev->of_node, "ti,k2g-qspi")) > + cqspi->wr_delay = 5 * DIV_ROUND_UP(NSEC_PER_SEC, > + cqspi->master_ref_clk_hz); Use the data pointer in the of_device_id table and put the delay value there. > > ret = devm_request_irq(dev, irq, cqspi_irq_handler, 0, > pdev->name, cqspi); > @@ -1285,6 +1297,7 @@ static const struct dev_pm_ops cqspi__dev_pm_ops = { > > static const struct of_device_id cqspi_dt_ids[] = { > {.compatible = "cdns,qspi-nor",}, > + {.compatible = "ti,k2g-qspi",}, > { /* end of table */ } > }; > > -- > 2.13.3 >