From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Mundt Date: Tue, 12 Mar 2013 15:41:41 +0000 Subject: Re: Serial port RTPM/Suspend issues Message-Id: <20130312154140.GB20355@linux-sh.org> List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-sh@vger.kernel.org On Tue, Mar 12, 2013 at 04:31:57PM +0100, Bastian Hecht wrote: > 2013/3/12 Paul Mundt : > > On Tue, Mar 12, 2013 at 03:50:42PM +0100, Bastian Hecht wrote: > >> To avoid confusion, let me add: Garbage is produced when waking, not > >> in the shutdown process. > > > > I assume this is just data left in the FIFO that hasn't been drained that > > comes back in an undefined state due to losing the clock? > > The port hangs after printing a couple of dozens of characters. The > system itself seems stable - I can log into it using ssh. > Does this fit with your theory? > There are two theories really, residual FIFO data or baud rate generation issues. Your dozens of characters thing seems to support the former, given the FIFO size -- the latter would more likely generate a lot more spew. > By the way I am using a shallow sleep to test it. Just cpu_do_idle(). Can you see how it goes booting with nohlt? We have seen issues between BL bit and sleep interactivity before.