From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33181) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aRDms-0005Hl-Cb for qemu-devel@nongnu.org; Thu, 04 Feb 2016 01:53:07 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aRDmp-0008B5-3N for qemu-devel@nongnu.org; Thu, 04 Feb 2016 01:53:06 -0500 Message-ID: <56B2F4E3.6010807@huawei.com> Date: Thu, 4 Feb 2016 14:51:15 +0800 From: Shannon Zhao MIME-Version: 1.0 References: <1454005340-15682-1-git-send-email-wei@redhat.com> <56B1A90E.3000506@msgid.tls.msk.ru> <56B22469.7040308@redhat.com> <56B2AD13.6030504@huawei.com> <56B2EB3E.2000908@redhat.com> In-Reply-To: <56B2EB3E.2000908@redhat.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 1/1] arm: virt: change GPIO trigger interrupt to pulse List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Wei Huang , Peter Maydell , Michael Tokarev Cc: QEMU Trivial , QEMU Developers , Shannon Zhao On 2016/2/4 14:10, Wei Huang wrote: > > On 02/03/2016 07:44 PM, Shannon Zhao wrote: >> > >> > >> > On 2016/2/4 0:01, Wei Huang wrote: >>> >> >>> >> On 2/3/16 04:46, Peter Maydell wrote: >>>>> >>>> On 3 February 2016 at 07:15, Michael Tokarev wrote: >>>>>>> >>>>>> 28.01.2016 21:22, Wei Huang wrote: >>>>>>>>> >>>>>>>> When QEMU is hook'ed up with libvirt/virsh, the first ACPI reboot >>>>>>>>> >>>>>>>> request will succeed; but the following shutdown/reboot requests >>>>>>>>> >>>>>>>> fail to trigger VMs to react. Notice that in mach-virt machine >>>>>>>>> >>>>>>>> model GPIO is defined as edge-triggered and active-high in ACPI. >>>>>>>>> >>>>>>>> This patch changes the behavior of powerdown notifier from PULLUP >>>>>>>>> >>>>>>>> to PULSE. It solves the problem described above (i.e. reboot >>>>>>>>> >>>>>>>> continues to work). >>>>>>> >>>>>> >>>>>>> >>>>>> So, what's the outcome of this? :) >>>>> >>>> >>>>> >>>> This patch is definitely wrong. The patch to fix up the >>>>> >>>> gpio reset stuff is definitely the right idea. Whether it >>>>> >>>> fixes the reported failure or some further change is also >>>>> >>>> needed is currently unclear. >>> >> I will NAK this one for now. Please see V2 patch, which is necessary. In >>> >> the meanwhile, I think there is a problem with pulling-up only in >>> >> current implementation. Let me debug Shannon's DT problem first. >>> >> >> > Hi Wei, >> > >> > The reason of DT problem is that when we use qemu_irq_pulse(i.e >> > qemu_set_irq(qdev_get_gpio_in(pl061_dev, 3), 1); >> > qemu_set_irq(qdev_get_gpio_in(pl061_dev, 3), 0);), it will inject the >> > GPIO interrupt until it executes >> > qemu_set_irq(qdev_get_gpio_in(pl061_dev, 3), 0) because the qemu main >> > thread is serialized and then guest will get the button value as zero, >> > so it's failed to report the input event. >> > >> > See gpio_keys_gpio_report_event >> > in drivers/input/keyboard/gpio_keys.c >> > int state = gpio_get_value_cansleep(button->gpio); >> > >> > The state is always zero. > I reversed the order of edge pulling. The state is 1 according to printk > inside gpio_keys driver. However the reboot still failed with two > reboots (1 very early, 1 later). > Because to make the input work, it should call input_event twice I think. input_event(input, type, button->code, 1) means the button pressed input_event(input, type, button->code, 0) means the button released But We only see guest entering gpio_keys_gpio_report_event once. My original purpose is like below: call qemu_set_irq(qdev_get_gpio_in(pl061_dev, 3), 1) to make guest execute input_event(input, type, button->code, 1) call qemu_set_irq(qdev_get_gpio_in(pl061_dev, 3), 0) to make guest execute input_event(input, type, button->code, 0). But even though it calls qemu_set_irq twice, it only calls pl061_update once in qemu. -- Shannon