From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: earlycon issues in -next with amba-pl011 updates Date: Thu, 3 Sep 2015 08:52:55 -0700 Message-ID: <20150903155255.GA28336@kroah.com> References: <20150810232312.GB10728@bivouac.eciton.net> <55E81F93.1020104@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <55E81F93.1020104@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Marc Zyngier Cc: Jun Nie , Tyler Baker , linux-arm-kernel@lists.infradead.org, Leif Lindholm , linux-serial@vger.kernel.org List-Id: linux-serial@vger.kernel.org On Thu, Sep 03, 2015 at 11:23:15AM +0100, Marc Zyngier wrote: > On 11/08/15 02:48, Jun Nie wrote: > > 2015-08-11 7:23 GMT+08:00 Leif Lindholm : > >> Hi all, > >> > >> The kernelci.org bot picked up a complete boot failure (no output past > >> UEFI stub) with next-20150806 and Tyler bisected it down to somewhere > >> in > >> 8cd90e5 uart: pl011: Add support to ZTE ZX296702 uart > >> 09dcc7d uart: pl011: Improve LCRH register access decision > >> 2c096a9 uart: pl011: Introduce register look up table > >> 7b753f3 uart: pl011: Introduce register accessor > >> > >> The issue only appears with earlycon on command line, for pl011 > >> consoles. > >> > >> Some investigation shows that the cause lies with > >> commit 7b753f318d14 ("uart: pl011: Introduce register accessor") > >> and > >> commit 2c096a9eedc6 ("uart: pl011: Introduce register look up table") > >> > >> Specifically, the changes to pl011_putc() are incorrect: > >> The new pl011_ accessors take a (struct uart_amba_port *) input, but > >> pl011_putc() directly uses the incoming (struct uart_port *) for this. > >> > >> Apart from ending up with an unintended/incorrect UART base address, > >> the introduction of the lookup table for register offsets also means > >> the accessors try to dereference (struct uart_amba_port *)->reg_lut. > >> > >> The below is a hack that shows/resolves the issue, but some > >> refactoring of the original patches might be in order. > >> > >> / > >> Leif > > > > Leif, > > > > Sorry for the inconvenience. I do not have idea of early console till > > now and I always have debug console for early panic debug. Learned > > more from this issue. > > > > Suppose Peter's patch will resolve your issue. > > [+ Greg KH] > > So -next has now been broken for a while on a number of ARM platforms > because of this (they simply cannot boot), and no progress has been made > towards resolving this problem. > > Can we please drop this series (at least commits 7b753f3 and following) > from -next until is has been reworked and reviewed? I don't have any patches in my -next tree, everything is in Linus's tree now. So if I've missed something, or need to revert something, please let me know specifcally what to do. thanks, greg k-h