[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[Fathi Boudra]

vexpress_defconfig is known broken on some use-cases. This serie of
patches allow to boot test Versatile Express using a regular filesystem
on SD card.

Fathi Boudra (3):
  ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem
  ARM: vexpress_defconfig: Enable voltage regulator support
  ARM: vexpress_defconfig: Enable ext4 filesystem

 arch/arm/configs/vexpress_defconfig | 5 +++++
 1 file changed, 5 insertions(+)

-- 
1.8.1.2

[PATCH 1/3] ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem

[Fathi Boudra]

udev no longer creates device nodes under /dev and it has to be managed
by the kernel devtmpfs filesystem.

This means that a kernel built with the current config will not boot on
a system with a recent udev:

mount: mounting udev on /dev failed: No such device
W: devtmpfs not available, falling back to tmpfs for /dev

Also, it is good to have /dev automatically mounted since some
non-initramfs based setups assumes this and don't manually mount it.

Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
---
 arch/arm/configs/vexpress_defconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
index f2de51f..3f970f1 100644
--- a/arch/arm/configs/vexpress_defconfig
+++ b/arch/arm/configs/vexpress_defconfig
@@ -45,6 +45,8 @@ CONFIG_IP_PNP_BOOTP=y
 # CONFIG_IPV6 is not set
 # CONFIG_WIRELESS is not set
 CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
+CONFIG_DEVTMPFS=y
+CONFIG_DEVTMPFS_MOUNT=y
 CONFIG_MTD=y
 CONFIG_MTD_CONCAT=y
 CONFIG_MTD_PARTITIONS=y
-- 
1.8.1.2

[PATCH 1/3] ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem

[Pawel Moll]

On Tue, 2013-08-20 at 22:02 +0100, Fathi Boudra wrote:
> udev no longer creates device nodes under /dev and it has to be managed
> by the kernel devtmpfs filesystem.
> 
> This means that a kernel built with the current config will not boot on
> a system with a recent udev:
> 
> mount: mounting udev on /dev failed: No such device
> W: devtmpfs not available, falling back to tmpfs for /dev
> 
> Also, it is good to have /dev automatically mounted since some
> non-initramfs based setups assumes this and don't manually mount it.
> 
> Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
> ---
>  arch/arm/configs/vexpress_defconfig | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
> index f2de51f..3f970f1 100644
> --- a/arch/arm/configs/vexpress_defconfig
> +++ b/arch/arm/configs/vexpress_defconfig
> @@ -45,6 +45,8 @@ CONFIG_IP_PNP_BOOTP=y
>  # CONFIG_IPV6 is not set
>  # CONFIG_WIRELESS is not set
>  CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
> +CONFIG_DEVTMPFS=y

This makes sense...

> +CONFIG_DEVTMPFS_MOUNT=y

... but I'm not so sure about this one. Normally it's up to the boot
scripts to decide when to mount the devtmpfs. And yes - I know it's
required to boot Ubuntu-based rootfs without initramfs, but that's
Ubuntu's problem, really.

>  CONFIG_MTD=y
>  CONFIG_MTD_CONCAT=y
>  CONFIG_MTD_PARTITIONS=y

[PATCH 1/3] ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem

[Fathi Boudra]

On 21 August 2013 13:46, Pawel Moll <pawel.moll@arm.com> wrote:
> On Tue, 2013-08-20 at 22:02 +0100, Fathi Boudra wrote:
>> udev no longer creates device nodes under /dev and it has to be managed
>> by the kernel devtmpfs filesystem.
>>
>> This means that a kernel built with the current config will not boot on
>> a system with a recent udev:
>>
>> mount: mounting udev on /dev failed: No such device
>> W: devtmpfs not available, falling back to tmpfs for /dev
>>
>> Also, it is good to have /dev automatically mounted since some
>> non-initramfs based setups assumes this and don't manually mount it.
>>
>> Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
>> ---
>>  arch/arm/configs/vexpress_defconfig | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
>> index f2de51f..3f970f1 100644
>> --- a/arch/arm/configs/vexpress_defconfig
>> +++ b/arch/arm/configs/vexpress_defconfig
>> @@ -45,6 +45,8 @@ CONFIG_IP_PNP_BOOTP=y
>>  # CONFIG_IPV6 is not set
>>  # CONFIG_WIRELESS is not set
>>  CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
>> +CONFIG_DEVTMPFS=y
>
> This makes sense...
>
>> +CONFIG_DEVTMPFS_MOUNT=y
>
> ... but I'm not so sure about this one. Normally it's up to the boot
> scripts to decide when to mount the devtmpfs. And yes - I know it's
> required to boot Ubuntu-based rootfs without initramfs, but that's
> Ubuntu's problem, really.

Sure, I can workaround in my build system but why is it an issue to enable it?
Obviously, it resolves my use case to boot test vexpress with Linaro
images and doesn't introduce a particular problem afaics.

>>  CONFIG_MTD=y
>>  CONFIG_MTD_CONCAT=y
>>  CONFIG_MTD_PARTITIONS=y

[PATCH 2/3] ARM: vexpress_defconfig: Enable voltage regulator support

[Fathi Boudra]

It is needed for the MMC controller and allows to use the SD card:

mmc0: host doesn't support card's voltages
mmc0: error -22 whilst initialising SD card

Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
---
 arch/arm/configs/vexpress_defconfig | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
index 3f970f1..c2f7ca1 100644
--- a/arch/arm/configs/vexpress_defconfig
+++ b/arch/arm/configs/vexpress_defconfig
@@ -77,6 +77,8 @@ CONFIG_SERIAL_AMBA_PL011_CONSOLE=y
 CONFIG_LEGACY_PTY_COUNT=16
 # CONFIG_HW_RANDOM is not set
 # CONFIG_HWMON is not set
+CONFIG_REGULATOR=y
+CONFIG_REGULATOR_VEXPRESS=y
 CONFIG_FB=y
 CONFIG_FB_ARMCLCD=y
 CONFIG_FRAMEBUFFER_CONSOLE=y
-- 
1.8.1.2

[PATCH 2/3] ARM: vexpress_defconfig: Enable voltage regulator support

[Pawel Moll]

On Tue, 2013-08-20 at 22:02 +0100, Fathi Boudra wrote:
> It is needed for the MMC controller and allows to use the SD card:
> 
> mmc0: host doesn't support card's voltages
> mmc0: error -22 whilst initialising SD card
> 
> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
> Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
> ---
>  arch/arm/configs/vexpress_defconfig | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
> index 3f970f1..c2f7ca1 100644
> --- a/arch/arm/configs/vexpress_defconfig
> +++ b/arch/arm/configs/vexpress_defconfig
> @@ -77,6 +77,8 @@ CONFIG_SERIAL_AMBA_PL011_CONSOLE=y
>  CONFIG_LEGACY_PTY_COUNT=16
>  # CONFIG_HW_RANDOM is not set
>  # CONFIG_HWMON is not set
> +CONFIG_REGULATOR=y
> +CONFIG_REGULATOR_VEXPRESS=y

The REGULATOR_VEXPRESS is not necessary to "fix" the MMC issue.
REGULATOR=y will make the REGULATOR_FIXED_VOLTAGE being selected, which
is enough.

Pawe?

[PATCH 3/3] ARM: vexpress_defconfig: Enable ext4 filesystem

[Fathi Boudra]

An ext4 partition could be used to store the root file system.
The kernel need to have built-in support for ext4 to be able to mount
the VFS root on boot.

Signed-off-by: Fathi Boudra <fathi.boudra@linaro.org>
---
 arch/arm/configs/vexpress_defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/configs/vexpress_defconfig b/arch/arm/configs/vexpress_defconfig
index c2f7ca1..e9ab454 100644
--- a/arch/arm/configs/vexpress_defconfig
+++ b/arch/arm/configs/vexpress_defconfig
@@ -119,6 +119,7 @@ CONFIG_EXT2_FS=y
 CONFIG_EXT3_FS=y
 # CONFIG_EXT3_DEFAULTS_TO_ORDERED is not set
 # CONFIG_EXT3_FS_XATTR is not set
+CONFIG_EXT4_FS=y
 CONFIG_VFAT_FS=y
 CONFIG_TMPFS=y
 CONFIG_JFFS2_FS=y
-- 
1.8.1.2

[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[Jon Medhurst (Tixy)]

On Wed, 2013-08-21 at 00:02 +0300, Fathi Boudra wrote:
> vexpress_defconfig is known broken on some use-cases. This serie of
> patches allow to boot test Versatile Express using a regular filesystem
> on SD card.
> 
> Fathi Boudra (3):
>   ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem
>   ARM: vexpress_defconfig: Enable voltage regulator support
>   ARM: vexpress_defconfig: Enable ext4 filesystem
> 
>  arch/arm/configs/vexpress_defconfig | 5 +++++
>  1 file changed, 5 insertions(+)

One good question is who do you have to convince to get these changes
accepted (or rejected)?

The original config was added by Linus Walleij through Russell's tree
(who is the maintainer according to get_maintainer.pl), and as of late,
Pawel Moll seems to have been acting a vexpress maintainer. I've added
those names to the CC list.

I suspect that nobody really cases that much, but it would be good to
get some feedback or if there is silence, just ask the armsoc people to
take the changes?

-- 
Tixy

[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[Pawel Moll]

On Wed, 2013-08-21 at 10:05 +0100, Jon Medhurst (Tixy) wrote:
> On Wed, 2013-08-21 at 00:02 +0300, Fathi Boudra wrote:
> > vexpress_defconfig is known broken on some use-cases. This serie of
> > patches allow to boot test Versatile Express using a regular filesystem
> > on SD card.
> > 
> > Fathi Boudra (3):
> >   ARM: vexpress_defconfig: Enable and automount devtmpfs filesystem
> >   ARM: vexpress_defconfig: Enable voltage regulator support
> >   ARM: vexpress_defconfig: Enable ext4 filesystem
> > 
> >  arch/arm/configs/vexpress_defconfig | 5 +++++
> >  1 file changed, 5 insertions(+)
> 
> One good question is who do you have to convince to get these changes
> accepted (or rejected)?

This gets down to the question do we actually want the
vexpress_defconfig at all? I was considering removing it completely as
multi_v7_defconfig should do the job (potentially subject to an extra
config option or two), but if there really is a need for vexpress-only
one, I can take the changes and queue it for the next-next merge window.

Pawe?

[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[Russell King - ARM Linux]

On Wed, Aug 21, 2013 at 11:51:53AM +0100, Pawel Moll wrote:
> This gets down to the question do we actually want the
> vexpress_defconfig at all? I was considering removing it completely as
> multi_v7_defconfig should do the job (potentially subject to an extra
> config option or two), but if there really is a need for vexpress-only
> one, I can take the changes and queue it for the next-next merge window.

The removal of that configuration will break two of the nightly builds
I run.

[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[Linus Walleij]

On Wed, Aug 21, 2013 at 12:51 PM, Pawel Moll <pawel.moll@arm.com> wrote:

> This gets down to the question do we actually want the
> vexpress_defconfig at all?

I added it because people were complaining that I was not
testing code against Vexpress and there was no way to
conveniently do that without a defconfig.

It is also used in Rothwells kisskb:
http://kisskb.ellerman.id.au/kisskb/branch/9/

Yours,
Linus Walleij

[PATCH 0/3] ARM: vexpress_defconfig: Allow to boot using a regular filesystem on SD card

[Christoffer Dall]

On 21 August 2013 15:57, Linus Walleij <linus.walleij@linaro.org> wrote:
> On Wed, Aug 21, 2013 at 12:51 PM, Pawel Moll <pawel.moll@arm.com> wrote:
>
>> This gets down to the question do we actually want the
>> vexpress_defconfig at all?
>
> I added it because people were complaining that I was not
> testing code against Vexpress and there was no way to
> conveniently do that without a defconfig.
>
> It is also used in Rothwells kisskb:
> http://kisskb.ellerman.id.au/kisskb/branch/9/
>
And it's mentioned in a wide variety of guides concerning building
QEMU/KVM guest images - I think it would be premature to remove it.

-Christoffer