Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933328AbbGVJdU (ORCPT ); Wed, 22 Jul 2015 05:33:20 -0400 Received: from mail-pd0-f182.google.com ([209.85.192.182]:33720 "EHLO mail-pd0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756349AbbGVJdR (ORCPT ); Wed, 22 Jul 2015 05:33:17 -0400 Message-ID: <55AF6353.1080204@linaro.org> Date: Wed, 22 Jul 2015 17:33:07 +0800 From: Hanjun Guo User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Marc Zyngier , Lorenzo Pieralisi CC: Thomas Gleixner , Jiang Liu , Jason Cooper , "linux-acpi@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Tomasz Nowicki , "Rafael J. Wysocki" , "suravee.suthikulpanit@amd.com" Subject: Re: [PATCH 5/5] irqchip: GIC: Switch ACPI support to stacked domains References: <1437473280-11431-1-git-send-email-marc.zyngier@arm.com> <1437473280-11431-6-git-send-email-marc.zyngier@arm.com> <20150721180542.GB32187@red-moon> <55AE8B8D.8050002@arm.com> <55AF55C2.4060807@linaro.org> <55AF5A10.5000106@arm.com> In-Reply-To: <55AF5A10.5000106@arm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5196 Lines: 125 On 07/22/2015 04:53 PM, Marc Zyngier wrote: > On 22/07/15 09:35, Hanjun Guo wrote: >> On 07/22/2015 02:12 AM, Marc Zyngier wrote: >>> On 21/07/15 19:05, Lorenzo Pieralisi wrote: >>>> On Tue, Jul 21, 2015 at 11:08:00AM +0100, Marc Zyngier wrote: >>>>> Now that the basic ACPI GSI code is irq domain aware, make sure >>>>> that the ACPI support in the GIC doesn't pointlessly deviate from >>>>> the DT path. >>>>> >>>>> Signed-off-by: Marc Zyngier >>>>> --- >>>>> drivers/irqchip/irq-gic.c | 17 ++++++----------- >>>>> include/linux/irqchip/arm-gic.h | 2 +- >>>>> 2 files changed, 7 insertions(+), 12 deletions(-) >>>>> >>>>> diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c >>>>> index b41ccf5..f5d365d 100644 >>>>> --- a/drivers/irqchip/irq-gic.c >>>>> +++ b/drivers/irqchip/irq-gic.c >>>>> @@ -813,8 +813,6 @@ static int gic_irq_domain_xlate(struct irq_domain *d, >>>>> { >>>>> unsigned long ret = 0; >>>>> >>>>> - if (irq_domain_get_of_node(d) != controller) >>>>> - return -EINVAL; >>>>> if (intsize < 3) >>>>> return -EINVAL; >>>>> >>>>> @@ -887,7 +885,7 @@ void gic_set_irqchip_flags(unsigned long flags) >>>>> >>>>> void __init gic_init_bases(unsigned int gic_nr, int irq_start, >>>>> void __iomem *dist_base, void __iomem *cpu_base, >>>>> - u32 percpu_offset, struct device_node *node) >>>>> + u32 percpu_offset, void *domain_token) >>>>> { >>>>> irq_hw_number_t hwirq_base; >>>>> struct gic_chip_data *gic; >>>>> @@ -946,8 +944,8 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start, >>>>> gic_irqs = 1020; >>>>> gic->gic_irqs = gic_irqs; >>>>> >>>>> - if (node) { /* DT case */ >>>>> - gic->domain = irq_domain_add_linear(node, gic_irqs, >>>>> + if (domain_token) { /* DT/ACPI case */ >>>>> + gic->domain = irq_domain_add_linear(domain_token, gic_irqs, >>>>> &gic_irq_domain_hierarchy_ops, >>>>> gic); >>>>> } else { /* Non-DT case */ >>>>> @@ -973,7 +971,7 @@ void __init gic_init_bases(unsigned int gic_nr, int irq_start, >>>>> irq_base = irq_start; >>>>> } >>>>> >>>>> - gic->domain = irq_domain_add_legacy(node, gic_irqs, irq_base, >>>>> + gic->domain = irq_domain_add_legacy(NULL, gic_irqs, irq_base, >>>>> hwirq_base, &gic_irq_domain_ops, gic); >>>>> } >>>>> >>>>> @@ -1132,12 +1130,9 @@ gic_v2_acpi_init(struct acpi_table_header *table) >>>>> } >>>>> >>>>> /* >>>>> - * Initialize zero GIC instance (no multi-GIC support). Also, set GIC >>>>> - * as default IRQ domain to allow for GSI registration and GSI to IRQ >>>>> - * number translation (see acpi_register_gsi() and acpi_gsi_to_irq()). >>>>> + * Initialize zero GIC instance (no multi-GIC support). >>>>> */ >>>>> - gic_init_bases(0, -1, dist_base, cpu_base, 0, NULL); >>>>> - irq_set_default_host(gic_data[0].domain); >>>>> + gic_init_bases(0, -1, dist_base, cpu_base, 0, (void *)ACPI_IRQ_MODEL_GIC); >>>> >>>> Nit: the acpi_irq_model_id enum starts from 0, I do not think we will >>>> use the IRQ domain look-up for the ACPI_IRQ_MODEL_PIC but we have >>>> to be careful anyway. >>> >>> Yeah, I noticed that one too, but couldn't imagine the PIC being >>> migrated to that model just yet. It looks like it would be pretty >>> harmless to set ACPI_IRQ_MODEL_PIC to 1, and introduce >>> ACPI_IRQ_MODEL_ILLEGAL as zero. >> >> I think this will be a problem, because acpi_irq_model_id enum actually >> is defined by the ACPI spec, and the value is used to report to BIOS >> the current interrupt model used by OS, see section 5.8.1 _PIC Method >> in ACPI 6.0: >> >> 0 ? PIC mode >> 1 ? APIC mode >> 2 ? SAPIC mode >> Other values ?Reserved > > Ah, right. > >> so we can't set ACPI_IRQ_MODEL_PIC to 1 as it may break the firmware, >> also _PIC method actually is not needed for ARM platform at all, we >> don't need to report to firmware the interrupt model used by OS on >> ARM, it only used by legacy IA platforms, actually I'm planning to >> remove acpi_irq_model_id on ARM64. > > Remove? I don't get it. Either ACPI_IRQ_MODEL_GIC is a leval value, and > you can't remove it, or it is not, and I wonder how it ended up here the > first place. The best solution is that we don't call _PIC method on ARM at all (acpi_irq_model is used for _PIC method), but we can live with it since there is no harm if ARM firmware don't care about the value or ARM firmware don't define _PIC method in DSDT. > >> So to me acpi_irq_model_id is suitable for the token, can we use > is *not* ? >> another one as the token? how about the GIC ID in the MADT table? >> and this also can be used for x86 (IOAPIC IDs) too. > > You can use whatever you want, just not a pointer. I'll add a token > parameter to the acpi_set_irq_model function that I mentioned in my > reply to Lorenzo. Thank you, I will wait for the v2 to rebase my ACPI GICv3 patches. Thanks Hanjun -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/