From mboxrd@z Thu Jan  1 00:00:00 1970
From: zhaoshenglong@huawei.com (Shannon Zhao)
Date: Wed, 18 Nov 2015 10:37:13 +0800
Subject: [PATCH v3 24/62] arm: Introduce a generic way to use a device
 from acpi
In-Reply-To: <564B38F6.9070101@citrix.com>
References: <1447753261-7552-1-git-send-email-shannon.zhao@linaro.org>
 <1447753261-7552-25-git-send-email-shannon.zhao@linaro.org>
 <564B2023.8010801@citrix.com> <564B29EA.3060107@huawei.com>
 <564B38F6.9070101@citrix.com>
Message-ID: <564BE459.6000006@huawei.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org



On 2015/11/17 22:25, Julien Grall wrote:
> On 17/11/15 13:21, Shannon Zhao wrote:
>>> AFAICT, it does only works for SPCR table used for UART device. For the
>>> GIC you've hardcoded the value and I can't find any version number in
>>> the table.
>>>
>> No, I didn't hardcode the GIC version. Since ACPI 6.0 introduces GIC
>> version in generic distributor table, it could get the version from
>> that. Please see [PATCH v3 28/62].
> 
> +    if ( dist->version == ACPI_MADT_GIC_VERSION_V2 )
> +        rc = acpi_device_init(DEVICE_GIC, NULL, GIC_V2);
> +    else if ( dist->version == ACPI_MADT_GIC_VERSION_V3 )
> +        rc = acpi_device_init(DEVICE_GIC, NULL, GIC_V3);
> 
> Every single time a new GIC version will be added, we will had to add
> another else if. I'm sorry but it's what I call hardcoding.
> 

Oh, I see. If it uses the enum acpi_madt_gic_version for ACPI GIC not
the enum gic_version, it could match 1:1. Something like below:

It uses ACPI_MADT_GIC_VERSION_V2 for GICv2.

ACPI_DEVICE_START(agicv2, "GICv2", DEVICE_GIC)
        .class_type = ACPI_MADT_GIC_VERSION_V2,
        .init = acpi_gicv2_preinit,
ACPI_DEVICE_END

Then get the GIC version from MADT table and call

acpi_device_init(DEVICE_GIC, NULL, dist->version);

How about this way?

Thanks,
-- 
Shannon