From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Mon, 23 Jan 2023 21:31:40 +0100 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1pK3Th-003Vk7-FI for lore@lore.pengutronix.de; Mon, 23 Jan 2023 21:31:40 +0100 Received: from bombadil.infradead.org ([2607:7c80:54:3::133]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1pK3Tf-0002Hz-9Z for lore@pengutronix.de; Mon, 23 Jan 2023 21:31:39 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=TCn5SthlfHUgRhTtLgPa/TS233quwHdlm+Zboxha6rE=; b=zjNpdDW+pLPkeXbZtdqNZw1kRK 3R5cHUk2wCGvAfJNAOdLB+1sg85h0S1sY1w81C2VRMZ1aa8fG2VWM9jqONkZ5yLlvO03hJs++tkpr FkMzceJy5DAt8XaMEqVbJ175XGJYdQdtuRe8qx37ocoe209pxL5SFbmKwN5rDziv3XU/PiMUmdgVt /x83+HHpnqU6E7JT9/myuMoLvXL6zMQPIHxVPbkl5hHSZSwrS5PPdkxV65M5vC7s11D2AJLJHgYqr S//RVxUmnqTLX5mjg8Uqve85G9SGU1Phb2Lt5WGvm2ZUviqJ6pIFCtlOuFWm99JWQvj6KNIkl8MlY h4FK7Jcw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pK3SI-001Ki0-II; Mon, 23 Jan 2023 20:30:14 +0000 Received: from out2.migadu.com ([188.165.223.204]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pK3SD-001KgW-S2 for barebox@lists.infradead.org; Mon, 23 Jan 2023 20:30:11 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jookia.org; s=key1; t=1674505808; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=TCn5SthlfHUgRhTtLgPa/TS233quwHdlm+Zboxha6rE=; b=pidazJLAErH763NmxrjsWHhZWON7qHpQr7rroHFtopvT4Gsl1jJAiJ3t1nUtB+PX5fMxgd wuPZksyw2D59nP1Jmk0V17L8vs4QgZh8hghSG3VAN4Rvw5hz4K6OUo5lxebvIv9J33o9OL D2Xj+IF767c8DMTH8zpNqkqlAwTVixx2zxRInpb8PXF8fohkvwzuTMxRZUqsnSoYg/R56m LrfO+ZXmsnYN13m98XZ+7oulx4Z9GyWcTCWWntoUqTW8w5L6mEOsMY4vbWo+b0lBSGOkRF WXQgjFTiyaDNw/ciqpgay5rmkWge34dOYw6vECUWrrc3V6G0gwUxXxdW6pXGCg== From: John Watts To: barebox@lists.infradead.org Cc: John Watts Date: Tue, 24 Jan 2023 07:18:20 +1100 Message-Id: <20230123201817.1084728-2-contact@jookia.org> In-Reply-To: <20230123201817.1084728-1-contact@jookia.org> References: <20230123201817.1084728-1-contact@jookia.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230123_123010_066552_9FF9E380 X-CRM114-Status: GOOD ( 11.59 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "barebox" X-SA-Exim-Connect-IP: 2607:7c80:54:3::133 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-5.0 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: [PATCH 2/2] imx6-mmdc: Revert calibration configuration on failure X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) When calibration fails it will clobber the existing configuration, even if the configuration was working but not ideal. Reverting calibration from a known bad value to a possibly good value gives a better chance of the memory working. I've tested this on the Novena board and had good success with it. U-Boot implements a similar solution in its write level calibration. Signed-off-by: John Watts --- arch/arm/mach-imx/imx6-mmdc.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/arm/mach-imx/imx6-mmdc.c b/arch/arm/mach-imx/imx6-mmdc.c index 908771626a..0d50b39566 100644 --- a/arch/arm/mach-imx/imx6-mmdc.c +++ b/arch/arm/mach-imx/imx6-mmdc.c @@ -25,11 +25,18 @@ static bool wlcalib_failed(void __iomem *ips) int mmdc_do_write_level_calibration(void) { + u32 ldectrl[4] = {0}; u32 esdmisc_val, zq_val; int errorcount = 0; u32 val; u32 ddr_mr1 = 0x4; + /* Store current calibration data in case of failure */ + ldectrl[0] = readl(P0_IPS + MPWLDECTRL0); + ldectrl[1] = readl(P0_IPS + MPWLDECTRL1); + ldectrl[2] = readl(P1_IPS + MPWLDECTRL0); + ldectrl[3] = readl(P1_IPS + MPWLDECTRL1); + /* disable DDR logic power down timer */ val = readl((P0_IPS + MDPDC)); val &= 0xffff00ff; @@ -69,8 +76,14 @@ int mmdc_do_write_level_calibration(void) while (readl(P0_IPS + MPWLGCR) & 0x00000001); /* check for any errors on both PHYs */ - if (wlcalib_failed(P0_IPS) || wlcalib_failed(P1_IPS)) + if (wlcalib_failed(P0_IPS) || wlcalib_failed(P1_IPS)) { + pr_debug("Calibration failed, rolling back calibration data\n"); + writel(ldectrl[0], P0_IPS + MPWLDECTRL0); + writel(ldectrl[1], P0_IPS + MPWLDECTRL1); + writel(ldectrl[2], P1_IPS + MPWLDECTRL0); + writel(ldectrl[3], P1_IPS + MPWLDECTRL1); errorcount++; + } pr_debug("Write leveling calibration completed\n"); -- 2.39.0