linux-kernel - [PATCH 2/3] spi: spi-nxp-fspi: add extra delay after dll locked

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250922-fspi-fix-v1-2-ff4315359d31@nxp.com>
Date: Mon, 22 Sep 2025 16:47:14 +0800
From: Haibo Chen <haibo.chen@....com>
To: Han Xu <han.xu@....com>, Yogesh Gaur <yogeshgaur.83@...il.com>, 
 Mark Brown <broonie@...nel.org>, Miquel Raynal <miquel.raynal@...tlin.com>, 
 Frank Li <Frank.Li@....com>
Cc: linux-spi@...r.kernel.org, imx@...ts.linux.dev, 
 linux-kernel@...r.kernel.org, Haibo Chen <haibo.chen@....com>
Subject: [PATCH 2/3] spi: spi-nxp-fspi: add extra delay after dll locked

From: Han Xu <han.xu@....com>

Due to the erratum ERR050272, the DLL lock status register STS2
[xREFLOCK, xSLVLOCK] bit may indicate DLL is locked before DLL is
actually locked. Add an extra 4us delay as a workaround.

refer to ERR050272, on Page 20.
https://www.nxp.com/docs/en/errata/IMX8_1N94W.pdf

Fixes: 99d822b3adc4 ("spi: spi-nxp-fspi: use DLL calibration when clock rate > 100MHz")
Signed-off-by: Han Xu <han.xu@....com>
Signed-off-by: Haibo Chen <haibo.chen@....com>
---
 drivers/spi/spi-nxp-fspi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/spi/spi-nxp-fspi.c b/drivers/spi/spi-nxp-fspi.c
index 4e82f9e900acb91c6de46559efd265f07cf4437d..96b3654b45abcaf53266ce9acac8d6578a19458a 100644
--- a/drivers/spi/spi-nxp-fspi.c
+++ b/drivers/spi/spi-nxp-fspi.c
@@ -721,6 +721,12 @@ static void nxp_fspi_dll_calibration(struct nxp_fspi *f)
 				   0, POLL_TOUT, true);
 	if (ret)
 		dev_warn(f->dev, "DLL lock failed, please fix it!\n");
+
+	/*
+	 * For ERR050272, DLL lock status bit is not accurate,
+	 * wait for 4us more as a workaround.
+	 */
+	udelay(4);
 }
 
 /*

-- 
2.34.1