From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hector Palacios Date: Fri, 4 Dec 2015 19:25:50 +0100 Subject: [U-Boot] [PATCH] ARM: imx: fsl_esdhc: fix usage of low 4 bits of sysctl register In-Reply-To: <5661D0C5.10805@nelint.com> References: <1449250332-24052-1-git-send-email-eric@nelint.com> <5661CFA7.9090308@nelint.com> <5661D0C5.10805@nelint.com> Message-ID: <5661DAAE.70106@digi.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Eric, On 12/04/2015 06:43 PM, Eric Nelson wrote: > On 12/04/2015 10:38 AM, Eric Nelson wrote: >> On 12/04/2015 10:32 AM, Eric Nelson wrote: >>> The low four bits of the SYSCTL register are reserved on the USDHC >>> controller on i.MX6 and i.MX7 processors, but are used for clocking >>> operations on earlier models. >>> >>> Guard against their usage by hiding the bit mask macros on those >>> processors. >>> >>> These bits are used to prevent glitches when changing clocks on >>> i.MX35 et al. Use the RSTA bit instead for i.MX6 and i.MX7. >>> >>> From the i.MX6DQ RM: >>> To prevent possible glitch on the card clock, clear the >>> FRC_SDCLK_ON bit when changing clock divisor value(SDCLKFS >>> or DVS in System Control Register) or setting RSTA bit. >>> >>> Signed-off-by: Eric Nelson >> >> I forgot to add an in-reply-to header. >> >> http://lists.denx.de/pipermail/u-boot/2015-December/thread.html#236651 >> >> > > Fabio, I haven't been able to reproduce the "mmc erase/ENGcm03648" > issue (with or without a code change) for a couple of hours now. > > Can you give this a spin? > > It seems unlikely to address the issue unless what we're seeing is a > side effect of a glitch while switching clocks. As Fabio, I can reproduce this 100% of the times. The patch does not fix it, though. -- Hector Palacios