Re: [PATCH 1/1] gma500_gfx: Avoid inserting gma500_gfx module for certain devices

[Alejandro Hernandez <alejandro.hernandez@linux.intel.com>]

On 05/10/15 03:26, Richard Purdie wrote:
> On Thu, 2015-10-01 at 20:23 +0000, Alejandro Hernandez wrote:
>> The gma500_gfx driver will match certain devices on which it causes incorrect functionality,
>> we want to avoid inserting this module, basicallly blacklist it for specific hardware,
>> but still allow it to work on other hardware by default; usually when we have an already working system,
>> using udev rules would do the job, but since we are building it, it is impossible to blacklist
>> a driver when a certain udev rule matches, since rootfs isn't writeable at this point during boot time,
>> the solution is to use modprobe install, which runs a certain command instead of inserting a matching module,
>> this command needs to insert the module manually afterwards and have a flag --ignore-install
>> so it doesnt create an infinite loop executing itself everytime it wants to insert the module,
>> busybox's modprobe doesn't provide this functionality, so a small hack had to be used to avoid
>> the infite loop instead.
>>
>> Signed-off-by: Alejandro Hernandez <alejandro.hernandez@linux.intel.com>
>> ---
>>   meta-yocto-bsp/conf/machine/genericx86.conf            |  2 ++
>>   .../gma500-gfx-check/gma500-gfx-check.conf             |  2 ++
>>   .../gma500-gfx-check/gma500-gfx-check.sh               | 11 +++++++++++
>>   .../gma500-gfx-check/gma500-gfx-check_1.0.bb           | 18 ++++++++++++++++++
>>   4 files changed, 33 insertions(+)
>>   create mode 100644 meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.conf
>>   create mode 100644 meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.sh
>>   create mode 100644 meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check_1.0.bb
>>
>> diff --git a/meta-yocto-bsp/conf/machine/genericx86.conf b/meta-yocto-bsp/conf/machine/genericx86.conf
>> index 2642cab..798b62ec 100644
>> --- a/meta-yocto-bsp/conf/machine/genericx86.conf
>> +++ b/meta-yocto-bsp/conf/machine/genericx86.conf
>> @@ -6,3 +6,5 @@
>>   DEFAULTTUNE ?= "core2-32"
>>   require conf/machine/include/tune-core2.inc
>>   require conf/machine/include/genericx86-common.inc
>> +
>> +MACHINE_ESSENTIAL_EXTRA_RRECOMMENDS += "gma500-gfx-check"
>> diff --git a/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.conf b/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.conf
>> new file mode 100644
>> index 0000000..69f109e
>> --- /dev/null
>> +++ b/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.conf
>> @@ -0,0 +1,2 @@
>> +# Mimic modprobe's install funcitonality with busybox's modprobe
>> +install gma500_gfx lsmod | grep gma || { gma500_gfx_check.sh || modprobe gma500_gfx; }
>> diff --git a/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.sh b/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.sh
>> new file mode 100644
>> index 0000000..0c7b3aa
>> --- /dev/null
>> +++ b/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check/gma500-gfx-check.sh
>> @@ -0,0 +1,11 @@
>> +#!/bin/sh
>> +
>> +# Check for devices we wish to avoid gma500_gfx for
>> +DEVICES="0x8119 0x4108"
>> +for DEVICE in $DEVICES; do
>> +    if udevadm trigger --subsystem-match=pci --verbose --attr-match=device=$DEVICE | grep "pci" >> /dev/null ; then
>> +        echo "Found $DEVICE, avoiding gma500_gfx module" >> /dev/kmsg;
>> +        exit 0
>> +    fi
>> +done
>> +exit 1
>> diff --git a/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check_1.0.bb b/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check_1.0.bb
>> new file mode 100644
>> index 0000000..c68dd7b
>> --- /dev/null
>> +++ b/meta-yocto-bsp/recipes-bsp/gma500-gfx-check/gma500-gfx-check_1.0.bb
>> @@ -0,0 +1,18 @@
>> +SUMMARY = "Intel gma500_gfx fix for certain hardware"
>> +DESCRIPTION = "Avoid inserting gma500_gfx module for certain hardware devices."
>> +LICENSE="GPLv2"
>> +LIC_FILES_CHKSUM = "file://${COREBASE}/meta/files/common-licenses/GPL-2.0;md5=801f80980d171dd6425610833a22dbe6"
>> +
>> +SRC_URI = "file://gma500-gfx-check.conf \
>> +	file://gma500-gfx-check.sh "
>> +
>> +do_install(){
>> +    install -d ${D}${sysconfdir}/modprobe.d/
>> +    install -m 755 ${WORKDIR}/gma500-gfx-check.sh ${D}${sysconfdir}/modprobe.d/gma500-gfx-check.sh
>> +    install -m 644 ${WORKDIR}/gma500-gfx-check.conf ${D}${sysconfdir}/modprobe.d/gma500-gfx-check.conf
>> +}
>> +
>> +FILES_${PN}="${sysconfdir}/modprobe.d/gma500-gfx-check.conf \
>> +             ${sysconfdir}/modprobe.d/gma500-gfx-check.sh"
>> +
>> +COMPATIBLE_MACHINE_genericx86 = "genericx86"
> This patch needs to go to the poky mailing list as its against
> meta-yocto. I think this should also be:
>
> COMPATIBLE_MACHINE = "genericx86"
>
> the other syntax is used to avoid certain issues in recipes like
> linux-yocto but there is no default COMPATIBLE_MACHINE here so using
> that override syntax isn't correct.
>
> Cheers,
>
> Richard
My mistake, I will fix this and send a v2