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From: Marc Zyngier <maz@kernel.org>
To: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>,
	linux-mips@vger.kernel.org, Huacai Chen <chenhc@lemote.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Jason Cooper <jason@lakedaemon.net>,
	Rob Herring <robh+dt@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Mauro Carvalho Chehab <mchehab+samsung@kernel.org>,
	"David S. Miller" <davem@davemloft.net>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Allison Randal <allison@lohutok.net>,
	linux-kernel@vger.kernel.org, devicetree@vger.kernel.org
Subject: Re: [PATCH v8 06/11] irqchip: mips-cpu: Convert to simple domain
Date: Wed, 25 Mar 2020 13:00:01 +0000	[thread overview]
Message-ID: <a69f727d37daac6e20ac08de022245b1@kernel.org> (raw)
In-Reply-To: <20200325123742.GA9911@alpha.franken.de>

On 2020-03-25 12:37, Thomas Bogendoerfer wrote:
> On Wed, Mar 25, 2020 at 11:54:59AM +0800, Jiaxun Yang wrote:
>> The old code is using legacy domain to setup irq_domain for CPU 
>> interrupts
>> which requires irq_desc to be preallocated.
>> 
>> However, when MIPS_CPU_IRQ_BASE >= 16, irq_desc for CPU IRQs may end 
>> up
>> unallocated and lead to incorrect behavior.
>> 
>> Thus we convert the legacy domain to simple domain which can allocate
>> irq_desc during initialization.
>> 
>> Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
>> Co-developed-by: Huacai Chen <chenhc@lemote.com>
>> Signed-off-by: Huacai Chen <chenhc@lemote.com>
>> Reviewed-by: Marc Zyngier <maz@kernel.org>
>> ---
>>  drivers/irqchip/irq-mips-cpu.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>> 
>> diff --git a/drivers/irqchip/irq-mips-cpu.c 
>> b/drivers/irqchip/irq-mips-cpu.c
>> index 95d4fd8f7a96..c3cf7fa76424 100644
>> --- a/drivers/irqchip/irq-mips-cpu.c
>> +++ b/drivers/irqchip/irq-mips-cpu.c
>> @@ -251,7 +251,7 @@ static void __init __mips_cpu_irq_init(struct 
>> device_node *of_node)
>>  	clear_c0_status(ST0_IM);
>>  	clear_c0_cause(CAUSEF_IP);
>> 
>> -	irq_domain = irq_domain_add_legacy(of_node, 8, MIPS_CPU_IRQ_BASE, 0,
>> +	irq_domain = irq_domain_add_simple(of_node, 8, MIPS_CPU_IRQ_BASE,
>>  					   &mips_cpu_intc_irq_domain_ops,
>>  					   NULL);
> 
> this breaks at least IP30 and guess it will break every platform where
> MIPS_CPU_IRQ_BASE == 0. add_legacy will always do 
> irq_domain_associate_many(),
> while add_simple doesn't do it, if first_irq == 0.
> 
> Marc, what is the reason not doing it all the time ? What's the correct
> way here to work with irq_domain_add_simple() in this case ?

On a fully DT-ified platform, using non-legacy irqdomains, virtual 
interrupts
are allocated as a "random" number, depending on the order of 
allocation,
and on demand.

The first_irq hack in irq_domain_add_simple() is just a way to still 
allocate
descriptors upfront (and I wish we could drop it...).

If you have legacy code that "knows" about the relationship between 
Linux's
virtual interrupt and the hwirq (that is only meaningful to the 
interrupt
controller), you're screwed, and need to stick to the legacy irqdomain.

It feels like the MIPS code is squarely in the latter case, so I guess 
this
patch is probably the wrong thing to do for this architecture.

Thanks,

         M.
-- 
Jazz is not dead. It just smells funny...

  parent reply	other threads:[~2020-03-25 13:00 UTC|newest]

Thread overview: 175+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-27  8:52 [PATCH 00/13] Modernize Loongson64 Machine Jiaxun Yang
2019-08-27  8:52 ` [PATCH 01/13] MIPS: Loongson64: Rename CPU TYPES Jiaxun Yang
2019-08-27  8:52 ` [PATCH 02/13] MIPS: Loongson64: Sepreate loongson2ef/loongson64 code Jiaxun Yang
2019-08-27 22:05   ` Aaro Koskinen
2019-08-28  0:37     ` Jiaxun Yang
2019-09-02 17:51       ` Aaro Koskinen
2019-08-27  8:52 ` [PATCH 03/13] MAINTAINERS: Fix entries for new loongson64 path Jiaxun Yang
2019-08-27  8:52 ` [PATCH 04/13] irqchip: Add driver for Loongson-3 I/O interrupt controller Jiaxun Yang
2019-08-27 16:45   ` Marc Zyngier
2019-08-28  0:27     ` Jiaxun Yang
2019-08-28  6:59       ` Marc Zyngier
2019-08-28 15:31         ` Jiaxun Yang
2019-08-28 16:02           ` Marc Zyngier
2019-08-27  8:52 ` [PATCH 05/13] dt-bindings: interrupt-controller: Add Loongson-3 IOINTC Jiaxun Yang
2019-08-27 13:08   ` Rob Herring
2019-08-27  8:52 ` [PATCH 06/13] irqchip: Add driver for Loongson-3 HyperTransport interrupt controller Jiaxun Yang
2019-08-27 12:53   ` Marc Zyngier
2019-08-27  8:52 ` [PATCH 07/13] dt-bindings: interrupt-controller: Add Loongson-3 HTINTC Jiaxun Yang
2019-08-27 12:49   ` Rob Herring
2019-08-27 14:08     ` Jiaxun Yang
2019-08-27  8:52 ` [PATCH 08/13] irqchip: i8259: Add plat-poll support Jiaxun Yang
2019-08-27  8:52 ` [PATCH 09/13] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2019-08-27  8:52 ` [PATCH 10/13] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2019-08-27  8:53 ` [PATCH 11/13] dt-bindings: mips: Add loongson cpus & boards Jiaxun Yang
2019-08-27 12:45   ` Rob Herring
2019-08-27 14:18     ` Jiaxun Yang
2019-08-27 20:41       ` Paul Burton
2019-08-28  0:15         ` Jiaxun Yang
2019-09-02 14:50         ` Rob Herring
2019-09-03  9:07           ` Paul Burton
2019-09-04  3:33             ` Huacai Chen
2019-08-27  8:53 ` [PATCH 12/13] MIPS: Loongson64: Add generic dts Jiaxun Yang
2019-08-27  8:53 ` [PATCH 13/13] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2019-08-27 13:25 ` Re:[PATCH 00/13] Modernize Loongson64 Machine 陈华才
2019-08-27 14:39   ` [PATCH " Jiaxun Yang
2019-08-30  4:25 ` [PATCH v1 00/18] " Jiaxun Yang
2019-08-30  4:25   ` [PATCH v1 01/18] MIPS: Loongson64: Rename CPU TYPES Jiaxun Yang
2019-08-30  4:25   ` [PATCH v1 02/18] MIPS: Loongson64: separate loongson2ef/loongson64 code Jiaxun Yang
2019-08-30  4:25   ` [PATCH v1 03/18] MAINTAINERS: Fix entries for new loongson64 path Jiaxun Yang
2019-08-30  4:25   ` [PATCH v1 04/18] irqchip: Export generic chip domain map/unmap functions Jiaxun Yang
2019-08-30  4:25   ` [PATCH v1 05/18] irqchip: Add driver for Loongson-3 I/O interrupt controller Jiaxun Yang
2019-08-30  4:25   ` [PATCH v1 06/18] dt-bindings: interrupt-controller: Add Loongson-3 IOINTC Jiaxun Yang
2019-09-05 14:42 ` [PATCH v2 00/19] Modernize Loongson64 Machine Jiaxun Yang
2019-09-05 14:42   ` [PATCH v2 01/19] MIPS: Loongson64: Rename CPU TYPES Jiaxun Yang
2019-09-05 14:42   ` [PATCH v2 02/19] MIPS: Loongson64: separate loongson2ef/loongson64 code Jiaxun Yang
2019-09-10  0:12     ` Paul Burton
2019-09-16  2:23       ` Huacai Chen
2019-09-18  0:38       ` Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 03/19] MAINTAINERS: Fix entries for new loongson64 path Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 04/19] irqchip: Export generic chip domain map/unmap functions Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 05/19] irqchip: Add driver for Loongson-3 I/O interrupt controller Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 06/19] dt-bindings: interrupt-controller: Add Loongson-3 IOINTC Jiaxun Yang
2019-09-17 21:26     ` Rob Herring
2019-09-05 14:43   ` [PATCH v2 07/19] irqchip: Add driver for Loongson-3 HyperTransport interrupt controller Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 08/19] dt-bindings: interrupt-controller: Add Loongson-3 HTINTC Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 09/19] irqchip: i8259: Add plat-poll support Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 10/19] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 11/19] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 12/19] dt-bindings: mips: Add loongson boards Jiaxun Yang
2019-09-30 13:23     ` Rob Herring
2019-09-05 14:43   ` [PATCH v2 13/19] dt-bindings: Document loongson vendor-prefix Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 14/19] MIPS: Loongson64: Add generic dts Jiaxun Yang
2019-09-07  2:53     ` Huacai Chen
2019-09-07  3:14       ` Jiaxun Yang
2019-09-30 13:20     ` Rob Herring
2019-09-05 14:43   ` [PATCH v2 15/19] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 16/19] GPIO: loongson: Drop Loongson-3A/3B support Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 17/19] MIPS: Loongson: Regenerate defconfigs Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 18/19] MAINTAINERS: Add new pathes to LOONGSON64 ARCHITECTURE Jiaxun Yang
2019-09-05 14:43   ` [PATCH v2 19/19] MAINTAINERS: Add myself as maintainer of LOONGSON64 Jiaxun Yang
2019-09-07  3:13   ` [PATCH v2 00/19] Modernize Loongson64 Machine Huacai Chen
2019-09-12  6:30 ` [PATCH 00/13] " Matt Turner
2019-09-18  0:33   ` Jiaxun Yang
2020-01-12  8:14 ` [PATCH v3 00/10] " Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 01/10] dt-bindings: Document loongson vendor-prefix Jiaxun Yang
2020-01-15 18:59     ` Paul Burton
2020-01-12  8:14   ` [PATCH v3 02/10] irqchip: Add driver for Loongson I/O interrupt controller Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 03/10] dt-bindings: interrupt-controller: Add Loongson IOINTC Jiaxun Yang
2020-01-13  3:44     ` Huacai Chen
2020-01-13  3:40       ` Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 04/10] irqchip: Add driver for Loongson-3 HyperTransport PIC controller Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 05/10] dt-bindings: interrupt-controller: Add Loongson-3 HTPIC Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 06/10] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 07/10] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 08/10] dt-bindings: mips: Add loongson boards Jiaxun Yang
2020-01-13  3:39     ` Huacai Chen
2020-01-12  8:14   ` [PATCH v3 09/10] MIPS: Loongson64: Add generic dts Jiaxun Yang
2020-01-12  8:14   ` [PATCH v3 10/10] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2020-01-13  3:38   ` [PATCH v3 00/10] Modernize Loongson64 Machine Huacai Chen
2020-02-21  5:09 ` [PATCH v4 00/10] Modernize Loongson64 Machine v4 Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 01/10] irqchip: Add driver for Loongson I/O Local Interrupt Controller Jiaxun Yang
2020-02-29  2:30     ` 回复:[PATCH " Jiaxun Yang
2020-03-07 14:50     ` [PATCH " Marc Zyngier
2020-02-21  5:09   ` [PATCH v4 02/10] dt-bindings: interrupt-controller: Add Loongson LIOINTC Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 03/10] irqchip: Add driver for Loongson-3 HyperTransport PIC controller Jiaxun Yang
2020-03-07 15:01     ` Marc Zyngier
2020-02-21  5:09   ` [PATCH v4 04/10] dt-bindings: interrupt-controller: Add Loongson-3 HTPIC Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 05/10] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 06/10] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 07/10] dt-bindings: mips: Add loongson boards Jiaxun Yang
2020-02-26 16:52     ` Rob Herring
2020-02-29  2:28       ` Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 08/10] MIPS: Loongson64: Add generic dts Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 09/10] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2020-02-21  5:09   ` [PATCH v4 10/10] MIPS: Loongson64: Move MIPS_CPU_IRQ_BASE Jiaxun Yang
2020-03-18  6:20 ` [PATCH v5 00/11] Modernize Loongson64 Machine v5 Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 01/11] irqchip: Add driver for Loongson I/O Local Interrupt Controller Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 02/11] irqchip: loongson-liointc: Workaround LPC IRQ Errata Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 03/11] dt-bindings: interrupt-controller: Add Loongson LIOINTC Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 04/11] irqchip: Add driver for Loongson-3 HyperTransport PIC controller Jiaxun Yang
2020-03-21 14:14     ` Marc Zyngier
2020-03-18  6:20   ` [PATCH v5 05/11] dt-bindings: interrupt-controller: Add Loongson-3 HTPIC Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 06/11] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 07/11] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 08/11] dt-bindings: mips: Add loongson boards Jiaxun Yang
2020-03-20 22:36     ` Rob Herring
2020-03-22  5:33     ` Zhou Yanjie
2020-03-18  6:20   ` [PATCH v5 09/11] MIPS: Loongson64: Add generic dts Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 10/11] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2020-03-18  6:20   ` [PATCH v5 11/11] MIPS: Loongson64: Move MIPS_CPU_IRQ_BASE Jiaxun Yang
2020-03-24 15:35 ` [PATCH v6 00/11] Modernize Loongson64 Machine v6 Jiaxun Yang
2020-03-24 15:35   ` [PATCH v6 01/11] irqchip: Add driver for Loongson I/O Local Interrupt Controller Jiaxun Yang
2020-03-24 15:35   ` [PATCH v6 02/11] irqchip: loongson-liointc: Workaround LPC IRQ Errata Jiaxun Yang
2020-03-25  1:52     ` Huacai Chen
2020-03-25  2:31       ` Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 03/11] dt-bindings: interrupt-controller: Add Loongson LIOINTC Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 04/11] irqchip: Add driver for Loongson-3 HyperTransport PIC controller Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 05/11] dt-bindings: interrupt-controller: Add Loongson-3 HTPIC Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 06/11] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 07/11] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 08/11] dt-bindings: mips: Add loongson boards Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 09/11] MIPS: Loongson64: Add generic dts Jiaxun Yang
2020-03-25  2:11     ` Huacai Chen
2020-03-25  2:08       ` Jiaxun Yang
2020-03-25  2:49         ` Huacai Chen
2020-03-24 15:36   ` [PATCH v6 10/11] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2020-03-24 15:36   ` [PATCH v6 11/11] MIPS: Loongson64: Move MIPS_CPU_IRQ_BASE Jiaxun Yang
2020-03-24 15:47   ` [PATCH v6 00/11] Modernize Loongson64 Machine v6 Marc Zyngier
2020-03-24 15:51     ` Jiaxun Yang
2020-03-24 18:07       ` Thomas Bogendoerfer
2020-03-25  2:28 ` [PATCH v7 00/12] " Jiaxun Yang
2020-03-25  2:28   ` [PATCH v7 01/12] irqchip: Add driver for Loongson I/O Local Interrupt Controller Jiaxun Yang
2020-03-25 11:25     ` Paul Cercueil
2020-03-25 11:35       ` Marc Zyngier
2020-03-25  2:28   ` [PATCH v7 01/12] MIPS: Loongson: Do not initialise statics to 0 Jiaxun Yang
2020-03-25  2:28   ` [PATCH v7 02/12] irqchip: loongson-liointc: Workaround LPC IRQ Errata Jiaxun Yang
2020-03-25  2:28   ` [PATCH v7 02/12] MIPS: DTS: CI20: add DT node for IR sensor Jiaxun Yang
2020-03-25  2:28   ` [PATCH v7 03/12] dt-bindings: interrupt-controller: Add Loongson LIOINTC Jiaxun Yang
2020-03-25  3:54 ` [PATCH v8 00/11] Modernize Loongson64 Machine v8 Jiaxun Yang
2020-03-25  3:54   ` [PATCH v8 01/11] irqchip: Add driver for Loongson I/O Local Interrupt Controller Jiaxun Yang
2020-03-25  3:54   ` [PATCH v8 02/11] irqchip: loongson-liointc: Workaround LPC IRQ Errata Jiaxun Yang
2020-03-25  3:54   ` [PATCH v8 03/11] dt-bindings: interrupt-controller: Add Loongson LIOINTC Jiaxun Yang
2020-03-25  3:54   ` [PATCH v8 04/11] irqchip: Add driver for Loongson-3 HyperTransport PIC controller Jiaxun Yang
2020-03-25  3:54   ` [PATCH v8 05/11] dt-bindings: interrupt-controller: Add Loongson-3 HTPIC Jiaxun Yang
2020-03-25  3:54   ` [PATCH v8 06/11] irqchip: mips-cpu: Convert to simple domain Jiaxun Yang
2020-03-25 12:37     ` Thomas Bogendoerfer
2020-03-25 12:48       ` Jiaxun Yang
2020-03-25 13:00       ` Marc Zyngier [this message]
2020-03-25 13:07         ` Jiaxun Yang
2020-03-25 13:57           ` Marc Zyngier
2020-03-25 13:59             ` Jiaxun Yang
2020-03-25 14:15               ` Marc Zyngier
2020-03-25 14:31                 ` Jiaxun Yang
2020-03-25 15:02                   ` Marc Zyngier
2020-03-25 15:04                   ` Thomas Bogendoerfer
2020-03-25 15:09                     ` Jiaxun Yang
2020-03-25 15:46                       ` Thomas Bogendoerfer
2020-03-25 16:02                         ` Jiaxun Yang
2020-03-25 16:31                           ` Thomas Bogendoerfer
2020-03-25  3:55   ` [PATCH v8 07/11] MIPS: Loongson64: Drop legacy IRQ code Jiaxun Yang
2020-03-25  3:55   ` [PATCH v8 08/11] dt-bindings: mips: Add loongson boards Jiaxun Yang
2020-03-25  3:55   ` [PATCH v8 09/11] MIPS: Loongson64: Add generic dts Jiaxun Yang
2020-03-25  3:55   ` [PATCH v8 10/11] MIPS: Loongson64: Load built-in dtbs Jiaxun Yang
2020-03-25  3:55   ` [PATCH v8 11/11] MAINTAINERS: Update Loongson64 entry Jiaxun Yang
2020-03-25 17:33   ` [PATCH v8 00/11] Modernize Loongson64 Machine v8 Thomas Bogendoerfer

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