[PATCH] of: property: Disable fw_devlink DT support for X86

[PATCH] of: property: Disable fw_devlink DT support for X86

[Saravana Kannan]

Andre reported fw_devlink=on breaking OLPC XO-1.5 [1].

OLPC XO-1.5 is an X86 system that uses a mix of ACPI and OF to populate
devices. The root cause seems to be ISA devices not setting their fwnode
field. But trying to figure out how to fix that doesn't seem worth the
trouble because the OLPC devicetree is very sparse/limited and fw_devlink
only adds the links causing this issue. Considering that there aren't many
users of OF in an X86 system, simply fw_devlink DT support for X86.

[1] - https://lore.kernel.org/lkml/3c1f2473-92ad-bfc4-258e-a5a08ad73dd0@web.de/
Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
Signed-off-by: Saravana Kannan <saravanak@google.com>
Cc: Andre Muller <andre.muller@web.de>
---
 drivers/of/property.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/of/property.c b/drivers/of/property.c
index 0c0dc2e369c0..3fd74bb34819 100644
--- a/drivers/of/property.c
+++ b/drivers/of/property.c
@@ -1444,6 +1444,9 @@ static int of_fwnode_add_links(struct fwnode_handle *fwnode)
 	struct property *p;
 	struct device_node *con_np = to_of_node(fwnode);
 
+	if (IS_ENABLED(CONFIG_X86))
+		return 0;
+
 	if (!con_np)
 		return -EINVAL;
 
-- 
2.33.0.309.g3052b89438-goog

Re: [PATCH] of: property: Disable fw_devlink DT support for X86

[Greg Kroah-Hartman]

On Thu, Sep 09, 2021 at 06:14:45PM -0700, Saravana Kannan wrote:
> Andre reported fw_devlink=on breaking OLPC XO-1.5 [1].
> 
> OLPC XO-1.5 is an X86 system that uses a mix of ACPI and OF to populate
> devices. The root cause seems to be ISA devices not setting their fwnode
> field. But trying to figure out how to fix that doesn't seem worth the
> trouble because the OLPC devicetree is very sparse/limited and fw_devlink
> only adds the links causing this issue. Considering that there aren't many
> users of OF in an X86 system, simply fw_devlink DT support for X86.
> 
> [1] - https://lore.kernel.org/lkml/3c1f2473-92ad-bfc4-258e-a5a08ad73dd0@web.de/
> Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> Cc: Andre Muller <andre.muller@web.de>
> ---
>  drivers/of/property.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/of/property.c b/drivers/of/property.c
> index 0c0dc2e369c0..3fd74bb34819 100644
> --- a/drivers/of/property.c
> +++ b/drivers/of/property.c
> @@ -1444,6 +1444,9 @@ static int of_fwnode_add_links(struct fwnode_handle *fwnode)
>  	struct property *p;
>  	struct device_node *con_np = to_of_node(fwnode);
>  
> +	if (IS_ENABLED(CONFIG_X86))
> +		return 0;

I love it :)

Anyway, getting a "Tested-by:" would be great to have here.  Andre, can
you verify this solves your issue?

thanks,

greg k-h

Re: [PATCH] of: property: Disable fw_devlink DT support for X86

[Andre Muller]

On 10/09/2021 08.15, Greg Kroah-Hartman wrote:
> On Thu, Sep 09, 2021 at 06:14:45PM -0700, Saravana Kannan wrote:
>> Andre reported fw_devlink=on breaking OLPC XO-1.5 [1].
>>
>> OLPC XO-1.5 is an X86 system that uses a mix of ACPI and OF to populate
>> devices. The root cause seems to be ISA devices not setting their fwnode
>> field. But trying to figure out how to fix that doesn't seem worth the
>> trouble because the OLPC devicetree is very sparse/limited and fw_devlink
>> only adds the links causing this issue. Considering that there aren't many
>> users of OF in an X86 system, simply fw_devlink DT support for X86.
>>
>> [1] - https://lore.kernel.org/lkml/3c1f2473-92ad-bfc4-258e-a5a08ad73dd0@web.de/
>> Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
>> Signed-off-by: Saravana Kannan <saravanak@google.com>
>> Cc: Andre Muller <andre.muller@web.de>
>> ---
>>   drivers/of/property.c | 3 +++
>>   1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/of/property.c b/drivers/of/property.c
>> index 0c0dc2e369c0..3fd74bb34819 100644
>> --- a/drivers/of/property.c
>> +++ b/drivers/of/property.c
>> @@ -1444,6 +1444,9 @@ static int of_fwnode_add_links(struct fwnode_handle *fwnode)
>>   	struct property *p;
>>   	struct device_node *con_np = to_of_node(fwnode);
>>
>> +	if (IS_ENABLED(CONFIG_X86))
>> +		return 0;
>
> I love it :)
>
> Anyway, getting a "Tested-by:" would be great to have here.  Andre, can
> you verify this solves your issue?

Yes, this patch fixes the issue, the drives work fine.
Tested-by: Andre Müller <andre.muller@web.de>

Thanks all,
Andre

>
> thanks,
>
> greg k-h
>

Re: [PATCH] of: property: Disable fw_devlink DT support for X86

[Greg Kroah-Hartman]

On Fri, Sep 10, 2021 at 12:37:01PM +0200, Andre Muller wrote:
> On 10/09/2021 08.15, Greg Kroah-Hartman wrote:
> > On Thu, Sep 09, 2021 at 06:14:45PM -0700, Saravana Kannan wrote:
> > > Andre reported fw_devlink=on breaking OLPC XO-1.5 [1].
> > > 
> > > OLPC XO-1.5 is an X86 system that uses a mix of ACPI and OF to populate
> > > devices. The root cause seems to be ISA devices not setting their fwnode
> > > field. But trying to figure out how to fix that doesn't seem worth the
> > > trouble because the OLPC devicetree is very sparse/limited and fw_devlink
> > > only adds the links causing this issue. Considering that there aren't many
> > > users of OF in an X86 system, simply fw_devlink DT support for X86.
> > > 
> > > [1] - https://lore.kernel.org/lkml/3c1f2473-92ad-bfc4-258e-a5a08ad73dd0@web.de/
> > > Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
> > > Signed-off-by: Saravana Kannan <saravanak@google.com>
> > > Cc: Andre Muller <andre.muller@web.de>
> > > ---
> > >   drivers/of/property.c | 3 +++
> > >   1 file changed, 3 insertions(+)
> > > 
> > > diff --git a/drivers/of/property.c b/drivers/of/property.c
> > > index 0c0dc2e369c0..3fd74bb34819 100644
> > > --- a/drivers/of/property.c
> > > +++ b/drivers/of/property.c
> > > @@ -1444,6 +1444,9 @@ static int of_fwnode_add_links(struct fwnode_handle *fwnode)
> > >   	struct property *p;
> > >   	struct device_node *con_np = to_of_node(fwnode);
> > > 
> > > +	if (IS_ENABLED(CONFIG_X86))
> > > +		return 0;
> > 
> > I love it :)
> > 
> > Anyway, getting a "Tested-by:" would be great to have here.  Andre, can
> > you verify this solves your issue?
> 
> Yes, this patch fixes the issue, the drives work fine.
> Tested-by: Andre Müller <andre.muller@web.de>

Wonderful!

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Or Rob, want me to take this through my tree?

thanks,

greg k-h

Re: [PATCH] of: property: Disable fw_devlink DT support for X86

[Rob Herring]

On Thu, 09 Sep 2021 18:14:45 -0700, Saravana Kannan wrote:
> Andre reported fw_devlink=on breaking OLPC XO-1.5 [1].
> 
> OLPC XO-1.5 is an X86 system that uses a mix of ACPI and OF to populate
> devices. The root cause seems to be ISA devices not setting their fwnode
> field. But trying to figure out how to fix that doesn't seem worth the
> trouble because the OLPC devicetree is very sparse/limited and fw_devlink
> only adds the links causing this issue. Considering that there aren't many
> users of OF in an X86 system, simply fw_devlink DT support for X86.
> 
> [1] - https://lore.kernel.org/lkml/3c1f2473-92ad-bfc4-258e-a5a08ad73dd0@web.de/
> Fixes: ea718c699055 ("Revert "Revert "driver core: Set fw_devlink=on by default""")
> Signed-off-by: Saravana Kannan <saravanak@google.com>
> Cc: Andre Muller <andre.muller@web.de>
> ---
>  drivers/of/property.c | 3 +++
>  1 file changed, 3 insertions(+)
> 

Applied, thanks!