From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan Roese Date: Mon, 22 Jul 2013 10:46:39 +0200 Subject: [U-Boot] [PATCH] usb: ehci-omap: Don't softreset USB High-speed Host (UHH) Module In-Reply-To: <1374480877-20643-1-git-send-email-rogerq@ti.com> References: <1374480877-20643-1-git-send-email-rogerq@ti.com> Message-ID: <51ECF16F.3000008@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 07/22/2013 10:14 AM, Roger Quadros wrote: > Fixes NFS root problems with Beagle (3530 ES1.0) when used with > external USB-ethernet adapter and "USB start" command used within > u-boot. > > Soft resetting the UHH module causes instability issues on > all OMAPs so we just avoid it. > > See OMAP36xx Errata > i571: USB host EHCI may stall when entering smart-standby mode > i660: USBHOST Configured In Smart-Idle Can Lead To a Deadlock > > On OMAP4/5, soft-resetting the UHH module can put it into > Smart-Idle mode and lead to a deadlock. > > On OMAP3 this doesn't seem to be the case but still instabilities > are observed on beagle (3530 ES1.0) if soft-reset is used. > e.g. NFS root failures with Linux kernel. > > Signed-off-by: Roger Quadros Thanks a lot for fixing this. With this patch, beagleboard is able to boot into an NFS root-fs. Even when USB is used previously in U-Boot. Without this patch NFS booting hangs randomly at some time. So: Tested-by: Stefan Roese Note: I think its a bit too late to take this patch into this release. So I suggest to apply it in the next merge-window. Thanks, Stefan