From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Stabellini Subject: Re: [PATCH 12/13] arm/xen: Get event-channel irq through HVM_PARAM when booting with ACPI Date: Fri, 20 Nov 2015 17:11:52 +0000 Message-ID: References: <1447754231-7772-1-git-send-email-shannon.zhao@linaro.org> <1447754231-7772-13-git-send-email-shannon.zhao@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Return-path: In-Reply-To: <1447754231-7772-13-git-send-email-shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org Cc: ian.campbell-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org, stefano.stabellini-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org, catalin.marinas-5wv7dgnIgG8@public.gmane.org, will.deacon-5wv7dgnIgG8@public.gmane.org, julien.grall-Sxgqhf6Nn4DQT0dZR+AlfA@public.gmane.org, ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, xen-devel-GuqFBffKawuEi8DpZVb4nw@public.gmane.org, christoffer.dall-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, peter.huangpeng-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, zhaoshenglong-hv44wF8Li93QT0dZR+AlfA@public.gmane.org, hangaohuai-hv44wF8Li93QT0dZR+AlfA@public.gmane.org List-Id: devicetree@vger.kernel.org On Tue, 17 Nov 2015, shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org wrote: > From: Shannon Zhao > > When booting with ACPI, it could get the event-channel irq through > HVM_PARAM_CALLBACK_IRQ. > > Signed-off-by: Shannon Zhao > --- > arch/arm/xen/enlighten.c | 23 +++++++++++++++++++---- > 1 file changed, 19 insertions(+), 4 deletions(-) > > diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c > index 1373d6d..b8e9db8 100644 > --- a/arch/arm/xen/enlighten.c > +++ b/arch/arm/xen/enlighten.c > @@ -25,6 +25,7 @@ > #include > #include > #include > +#include > > #include > > @@ -190,10 +191,24 @@ static int __init xen_guest_init(void) > if (!xen_domain()) > return 0; > > - xen_events_irq = irq_of_parse_and_map(xen_node, 0); > - if (!xen_events_irq) { > - pr_err("Xen event channel interrupt not found\n"); > - return -ENODEV; > + if (!acpi_disabled) { > + struct xen_hvm_param a; > + > + a.domid = DOMID_SELF; > + a.index = HVM_PARAM_CALLBACK_IRQ; > + if (HYPERVISOR_hvm_op(HVMOP_get_param, &a)) { If HYPERVISOR_hvm_op returns an error (ret != 0), I wouldn't bother checking for the returned value and simply return error. On the other hand, if HYPERVISOR_hvm_op is successful (ret == 0), then it might make sense to check for (a.value >> 56) == 3. > + if ((a.value >> 56) != 3) { > + pr_err("Can't get Xen event-channel irq\n"); > + return -ENODEV; > + } > + } > + xen_events_irq = a.value & 0xff; > + } else { > + xen_events_irq = irq_of_parse_and_map(xen_node, 0); > + if (!xen_events_irq) { > + pr_err("Xen event channel interrupt not found\n"); > + return -ENODEV; Please make the error message common and move it out of the if/else. > + } > } > > shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL); > -- > 2.1.0 >