From: r.sricharan@ti•com (Sricharan R)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH V3 16/16] irqchip: crossbar: allow for quirky hardware with direct hardwiring of GIC
Date: Mon, 23 Jun 2014 12:52:44 +0530 [thread overview]
Message-ID: <53A7D5C4.6090201@ti.com> (raw)
In-Reply-To: <20140621025723.GF21711@titan.lakedaemon.net>
Hi Jason,
On Saturday 21 June 2014 08:27 AM, Jason Cooper wrote:
> On Mon, Jun 16, 2014 at 04:53:16PM +0530, Sricharan R wrote:
>> From: Nishanth Menon <nm@ti•com>
>>
>> On certain platforms such as DRA7, SPIs 0, 1, 2, 3, 5, 6, 10, 131,
>> 132, 133 are direct wired to hardware blocks bypassing crossbar.
>> This quirky implementation is *NOT* supposed to be the expectation
>> of crossbar hardware usage. However, these are already marked in our
>> description of the hardware with SKIP and RESERVED where appropriate.
>>
>> Unfortunately, we need to be able to refer to these hardwired IRQs.
>> So, to request these, crossbar driver can use the existing information
>> from it's table that these SKIP/RESERVED maps are direct wired sources
>> and generic allocation/programming of crossbar should be avoided.
>>
>> Signed-off-by: Nishanth Menon <nm@ti•com>
>> Signed-off-by: Sricharan R <r.sricharan@ti•com>
>> ---
>> .../devicetree/bindings/arm/omap/crossbar.txt | 12 ++++++++++--
>> drivers/irqchip/irq-crossbar.c | 20 ++++++++++++++++++--
>> 2 files changed, 28 insertions(+), 4 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/omap/crossbar.txt b/Documentation/devicetree/bindings/arm/omap/crossbar.txt
>> index 8210ea4..438ccab 100644
>> --- a/Documentation/devicetree/bindings/arm/omap/crossbar.txt
>> +++ b/Documentation/devicetree/bindings/arm/omap/crossbar.txt
>> @@ -42,8 +42,10 @@ Documentation/devicetree/bindings/arm/gic.txt for further details.
>>
>> An interrupt consumer on an SoC using crossbar will use:
>> interrupts = <GIC_SPI request_number interrupt_level>
>> -request number shall be between 0 to that described by
>> -"ti,max-crossbar-sources"
>> +When the request number is between 0 to that described by
>> +"ti,max-crossbar-sources", it is assumed to be a crossbar mapping. If the
>> +request_number is greater than "ti,max-crossbar-sources", then it is mapped as a
>> +quirky hardware mapping direct to GIC.
>>
>> Example:
>> device_x at 0x4a023000 {
>> @@ -51,3 +53,9 @@ Example:
>> interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
>> ...
>> };
>> +
>> + device_y at 0x4a033000 {
>> + /* Direct mapped GIC SPI 1 used */
>> + interrupts = <GIC_SPI 401 IRQ_TYPE_LEVEL_HIGH>;
>
> Ideally, I'd like to see a macro here so that it's clear that we crossed
> a magic threshold. eg:
>
> #define MAX_SOURCES 400
> #define DIRECT_IRQ(irq) (MAX_SOURCES + irq)
> ...
> interrupts = <GIC_SPI DIRECT_IRQ(1) IRQ_TYPE_LEVEL_HIGH>;
>
> and, then:
>
> ti,max-crossbar-sources = <MAX_SOURCES>;
>
Ok, thats more good for readability. Will add that macro then.
Regards,
Sricharan
next prev parent reply other threads:[~2014-06-23 7:22 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-16 11:23 [PATCH V3 00/16] irqchip: crossbar: driver fixes Sricharan R
2014-06-16 11:23 ` [PATCH V3 01/16] irqchip: crossbar: dont use '0' to mark reserved interrupts Sricharan R
2014-06-16 11:23 ` [PATCH V3 02/16] irqchip: crossbar: check for premapped crossbar before allocating Sricharan R
2014-06-16 11:23 ` [PATCH V3 03/16] irqchip: crossbar: introduce ti,irqs-skip to skip Sricharan R
2014-06-21 2:33 ` Jason Cooper
2014-06-23 7:20 ` Sricharan R
2014-06-16 11:23 ` [PATCH V3 04/16] irqchip: crossbar: initialise the crossbar with a safe value Sricharan R
2014-06-16 11:23 ` [PATCH V3 05/16] irqchip: crossbar: change allocation logic by reversing search for free irqs Sricharan R
2014-06-16 11:23 ` [PATCH V3 06/16] irqchip: crossbar: remove IS_ERR_VALUE check Sricharan R
2014-06-16 11:23 ` [PATCH V3 07/16] irqchip: crossbar: fix sparse and checkpatch warnings Sricharan R
2014-06-16 11:23 ` [PATCH V3 08/16] irqchip: crossbar: fix kerneldoc warning Sricharan R
2014-06-16 11:23 ` [PATCH V3 09/16] irqchip: crossbar: return proper error value Sricharan R
2014-06-16 11:23 ` [PATCH V3 10/16] irqchip: crossbar: change the goto naming Sricharan R
2014-06-16 11:23 ` [PATCH V3 11/16] irqchip: crossbar: set cb pointer to null in case of error Sricharan R
2014-06-16 11:23 ` [PATCH V3 12/16] irqchip: crossbar: add kerneldoc for crossbar_domain_unmap callback Sricharan R
2014-06-16 11:23 ` [PATCH V3 13/16] irqchip: crossbar: introduce ti, max-crossbar-sources to identify valid crossbar mapping Sricharan R
2014-06-16 11:23 ` [PATCH V3 14/16] irqchip: crossbar: introduce centralized check for crossbar write Sricharan R
2014-06-16 11:23 ` [PATCH V3 15/16] documentation: dt: omap: crossbar: add description for interrupt consumer Sricharan R
2014-06-16 11:23 ` [PATCH V3 16/16] irqchip: crossbar: allow for quirky hardware with direct hardwiring of GIC Sricharan R
2014-06-21 2:57 ` Jason Cooper
2014-06-23 7:22 ` Sricharan R [this message]
2014-06-16 14:04 ` [PATCH V3 00/16] irqchip: crossbar: driver fixes Santosh Shilimkar
2014-06-17 8:54 ` Sricharan R
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