diff mbox series

[01/10] dm: fdt: scan for devices under /firmware too

Message ID 20180813155347.13844-2-jens.wiklander@linaro.org
State Superseded
Headers show
Series AVB using OP-TEE | expand

Commit Message

Jens Wiklander Aug. 13, 2018, 3:53 p.m. UTC
Just as /chosen may contain devices /firmware may contain devices, scan
for devices under /firmware too.

Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

---
 drivers/core/root.c | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

-- 
2.17.1

Comments

Tom Rini Aug. 15, 2018, 2:17 p.m. UTC | #1
On Mon, Aug 13, 2018 at 05:53:38PM +0200, Jens Wiklander wrote:

> Just as /chosen may contain devices /firmware may contain devices, scan

> for devices under /firmware too.

> 

> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

> ---

>  drivers/core/root.c | 15 ++++++++++-----

>  1 file changed, 10 insertions(+), 5 deletions(-)

> 

> diff --git a/drivers/core/root.c b/drivers/core/root.c

> index 72bcc7d7f2a3..0dca507e1187 100644

> --- a/drivers/core/root.c

> +++ b/drivers/core/root.c

> @@ -265,9 +265,15 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,

>  	for (offset = fdt_first_subnode(blob, offset);

>  	     offset > 0;

>  	     offset = fdt_next_subnode(blob, offset)) {

> -		/* "chosen" node isn't a device itself but may contain some: */

> -		if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {

> -			pr_debug("parsing subnodes of \"chosen\"\n");

> +		const char *node_name = fdt_get_name(blob, offset, NULL);

> +

> +		/*

> +		 * The "chosen" and "firmware" nodes aren't devices

> +		 * themselves but may contain some:

> +		 */

> +		if (!strcmp(node_name, "chosen") ||

> +		    !strcmp(node_name, "firmware")) {

> +			pr_debug("parsing subnodes of \"%s\"\n", node_name);

>  

>  			err = dm_scan_fdt_node(parent, blob, offset,

>  					       pre_reloc_only);


So, the /firmware node seems special.  Have you talked with the
devicetree folks to get it listed in the spec?  That would seem rather
valuable for something used by many parties.  Thanks!

-- 
Tom
Michal Simek Aug. 15, 2018, 2:30 p.m. UTC | #2
On 15.8.2018 16:17, Tom Rini wrote:
> On Mon, Aug 13, 2018 at 05:53:38PM +0200, Jens Wiklander wrote:
> 
>> Just as /chosen may contain devices /firmware may contain devices, scan
>> for devices under /firmware too.
>>
>> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
>> ---
>>  drivers/core/root.c | 15 ++++++++++-----
>>  1 file changed, 10 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/core/root.c b/drivers/core/root.c
>> index 72bcc7d7f2a3..0dca507e1187 100644
>> --- a/drivers/core/root.c
>> +++ b/drivers/core/root.c
>> @@ -265,9 +265,15 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,
>>  	for (offset = fdt_first_subnode(blob, offset);
>>  	     offset > 0;
>>  	     offset = fdt_next_subnode(blob, offset)) {
>> -		/* "chosen" node isn't a device itself but may contain some: */
>> -		if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {
>> -			pr_debug("parsing subnodes of \"chosen\"\n");
>> +		const char *node_name = fdt_get_name(blob, offset, NULL);
>> +
>> +		/*
>> +		 * The "chosen" and "firmware" nodes aren't devices
>> +		 * themselves but may contain some:
>> +		 */
>> +		if (!strcmp(node_name, "chosen") ||
>> +		    !strcmp(node_name, "firmware")) {
>> +			pr_debug("parsing subnodes of \"%s\"\n", node_name);
>>  
>>  			err = dm_scan_fdt_node(parent, blob, offset,
>>  					       pre_reloc_only);
> 
> So, the /firmware node seems special.  Have you talked with the
> devicetree folks to get it listed in the spec?  That would seem rather
> valuable for something used by many parties.  Thanks!
> 

some days ago we have sent a patch for this too.
https://lists.denx.de/pipermail/u-boot/2018-August/338049.html

It is using different way but it should do the same thing.

Thanks,
Michal
Tom Rini Aug. 15, 2018, 2:34 p.m. UTC | #3
On Wed, Aug 15, 2018 at 04:30:15PM +0200, Michal Simek wrote:
> On 15.8.2018 16:17, Tom Rini wrote:

> > On Mon, Aug 13, 2018 at 05:53:38PM +0200, Jens Wiklander wrote:

> > 

> >> Just as /chosen may contain devices /firmware may contain devices, scan

> >> for devices under /firmware too.

> >>

> >> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

> >> ---

> >>  drivers/core/root.c | 15 ++++++++++-----

> >>  1 file changed, 10 insertions(+), 5 deletions(-)

> >>

> >> diff --git a/drivers/core/root.c b/drivers/core/root.c

> >> index 72bcc7d7f2a3..0dca507e1187 100644

> >> --- a/drivers/core/root.c

> >> +++ b/drivers/core/root.c

> >> @@ -265,9 +265,15 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,

> >>  	for (offset = fdt_first_subnode(blob, offset);

> >>  	     offset > 0;

> >>  	     offset = fdt_next_subnode(blob, offset)) {

> >> -		/* "chosen" node isn't a device itself but may contain some: */

> >> -		if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {

> >> -			pr_debug("parsing subnodes of \"chosen\"\n");

> >> +		const char *node_name = fdt_get_name(blob, offset, NULL);

> >> +

> >> +		/*

> >> +		 * The "chosen" and "firmware" nodes aren't devices

> >> +		 * themselves but may contain some:

> >> +		 */

> >> +		if (!strcmp(node_name, "chosen") ||

> >> +		    !strcmp(node_name, "firmware")) {

> >> +			pr_debug("parsing subnodes of \"%s\"\n", node_name);

> >>  

> >>  			err = dm_scan_fdt_node(parent, blob, offset,

> >>  					       pre_reloc_only);

> > 

> > So, the /firmware node seems special.  Have you talked with the

> > devicetree folks to get it listed in the spec?  That would seem rather

> > valuable for something used by many parties.  Thanks!

> > 

> 

> some days ago we have sent a patch for this too.

> https://lists.denx.de/pipermail/u-boot/2018-August/338049.html

> 

> It is using different way but it should do the same thing.


OK, so it sounds like in terms of code clean-ups, we need something like
what you reference and then some further clean-ups on top of that
perhaps for other places to call dm_scan_fdt_ofnode_path() for special
cases.  And in terms of formalized specification bits, I do think
/firmware should perhaps get kicked up to the spec itself so that it's
very clear to all consumers.

-- 
Tom
Michal Simek Aug. 15, 2018, 2:50 p.m. UTC | #4
Hi Rob,

On 15.8.2018 16:34, Tom Rini wrote:
> On Wed, Aug 15, 2018 at 04:30:15PM +0200, Michal Simek wrote:
>> On 15.8.2018 16:17, Tom Rini wrote:
>>> On Mon, Aug 13, 2018 at 05:53:38PM +0200, Jens Wiklander wrote:
>>>
>>>> Just as /chosen may contain devices /firmware may contain devices, scan
>>>> for devices under /firmware too.
>>>>
>>>> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
>>>> ---
>>>>  drivers/core/root.c | 15 ++++++++++-----
>>>>  1 file changed, 10 insertions(+), 5 deletions(-)
>>>>
>>>> diff --git a/drivers/core/root.c b/drivers/core/root.c
>>>> index 72bcc7d7f2a3..0dca507e1187 100644
>>>> --- a/drivers/core/root.c
>>>> +++ b/drivers/core/root.c
>>>> @@ -265,9 +265,15 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,
>>>>  	for (offset = fdt_first_subnode(blob, offset);
>>>>  	     offset > 0;
>>>>  	     offset = fdt_next_subnode(blob, offset)) {
>>>> -		/* "chosen" node isn't a device itself but may contain some: */
>>>> -		if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {
>>>> -			pr_debug("parsing subnodes of \"chosen\"\n");
>>>> +		const char *node_name = fdt_get_name(blob, offset, NULL);
>>>> +
>>>> +		/*
>>>> +		 * The "chosen" and "firmware" nodes aren't devices
>>>> +		 * themselves but may contain some:
>>>> +		 */
>>>> +		if (!strcmp(node_name, "chosen") ||
>>>> +		    !strcmp(node_name, "firmware")) {
>>>> +			pr_debug("parsing subnodes of \"%s\"\n", node_name);
>>>>  
>>>>  			err = dm_scan_fdt_node(parent, blob, offset,
>>>>  					       pre_reloc_only);
>>>
>>> So, the /firmware node seems special.  Have you talked with the
>>> devicetree folks to get it listed in the spec?  That would seem rather
>>> valuable for something used by many parties.  Thanks!
>>>
>>
>> some days ago we have sent a patch for this too.
>> https://lists.denx.de/pipermail/u-boot/2018-August/338049.html
>>
>> It is using different way but it should do the same thing.
> 
> OK, so it sounds like in terms of code clean-ups, we need something like
> what you reference and then some further clean-ups on top of that
> perhaps for other places to call dm_scan_fdt_ofnode_path() for special
> cases.  And in terms of formalized specification bits, I do think
> /firmware should perhaps get kicked up to the spec itself so that it's
> very clear to all consumers.

I was also checking latest devicetree spec and there is no record about
/firmware node and how it is supposed to be used.

Thanks,
Michal
Rob Herring (Arm) Aug. 15, 2018, 3:31 p.m. UTC | #5
On Wed, Aug 15, 2018 at 8:51 AM Michal Simek <michal.simek@xilinx.com> wrote:
>
> Hi Rob,
>
> On 15.8.2018 16:34, Tom Rini wrote:
> > On Wed, Aug 15, 2018 at 04:30:15PM +0200, Michal Simek wrote:
> >> On 15.8.2018 16:17, Tom Rini wrote:
> >>> On Mon, Aug 13, 2018 at 05:53:38PM +0200, Jens Wiklander wrote:
> >>>
> >>>> Just as /chosen may contain devices /firmware may contain devices, scan
> >>>> for devices under /firmware too.
> >>>>
> >>>> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
> >>>> ---
> >>>>  drivers/core/root.c | 15 ++++++++++-----
> >>>>  1 file changed, 10 insertions(+), 5 deletions(-)
> >>>>
> >>>> diff --git a/drivers/core/root.c b/drivers/core/root.c
> >>>> index 72bcc7d7f2a3..0dca507e1187 100644
> >>>> --- a/drivers/core/root.c
> >>>> +++ b/drivers/core/root.c
> >>>> @@ -265,9 +265,15 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,
> >>>>    for (offset = fdt_first_subnode(blob, offset);
> >>>>         offset > 0;
> >>>>         offset = fdt_next_subnode(blob, offset)) {
> >>>> -          /* "chosen" node isn't a device itself but may contain some: */
> >>>> -          if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {
> >>>> -                  pr_debug("parsing subnodes of \"chosen\"\n");
> >>>> +          const char *node_name = fdt_get_name(blob, offset, NULL);
> >>>> +
> >>>> +          /*
> >>>> +           * The "chosen" and "firmware" nodes aren't devices
> >>>> +           * themselves but may contain some:
> >>>> +           */
> >>>> +          if (!strcmp(node_name, "chosen") ||
> >>>> +              !strcmp(node_name, "firmware")) {
> >>>> +                  pr_debug("parsing subnodes of \"%s\"\n", node_name);
> >>>>
> >>>>                    err = dm_scan_fdt_node(parent, blob, offset,
> >>>>                                           pre_reloc_only);
> >>>
> >>> So, the /firmware node seems special.  Have you talked with the
> >>> devicetree folks to get it listed in the spec?  That would seem rather
> >>> valuable for something used by many parties.  Thanks!
> >>>
> >>
> >> some days ago we have sent a patch for this too.
> >> https://lists.denx.de/pipermail/u-boot/2018-August/338049.html
> >>
> >> It is using different way but it should do the same thing.
> >
> > OK, so it sounds like in terms of code clean-ups, we need something like
> > what you reference and then some further clean-ups on top of that
> > perhaps for other places to call dm_scan_fdt_ofnode_path() for special
> > cases.  And in terms of formalized specification bits, I do think
> > /firmware should perhaps get kicked up to the spec itself so that it's
> > very clear to all consumers.
>
> I was also checking latest devicetree spec and there is no record about
> /firmware node and how it is supposed to be used.

Patches welcome. :)

It's really only a container to define non-discoverable firmware
interfaces. Typically accessed thru a secure call (for ARM) or a
mailbox. It is primarily just convention rather than a strict
requirement. We have to support firmware nodes at the top-level too
anyways.

Rob
Tom Rini Aug. 15, 2018, 3:43 p.m. UTC | #6
On Wed, Aug 15, 2018 at 09:31:30AM -0600, Rob Herring wrote:
> On Wed, Aug 15, 2018 at 8:51 AM Michal Simek <michal.simek@xilinx.com> wrote:

> >

> > Hi Rob,

> >

> > On 15.8.2018 16:34, Tom Rini wrote:

> > > On Wed, Aug 15, 2018 at 04:30:15PM +0200, Michal Simek wrote:

> > >> On 15.8.2018 16:17, Tom Rini wrote:

> > >>> On Mon, Aug 13, 2018 at 05:53:38PM +0200, Jens Wiklander wrote:

> > >>>

> > >>>> Just as /chosen may contain devices /firmware may contain devices, scan

> > >>>> for devices under /firmware too.

> > >>>>

> > >>>> Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

> > >>>> ---

> > >>>>  drivers/core/root.c | 15 ++++++++++-----

> > >>>>  1 file changed, 10 insertions(+), 5 deletions(-)

> > >>>>

> > >>>> diff --git a/drivers/core/root.c b/drivers/core/root.c

> > >>>> index 72bcc7d7f2a3..0dca507e1187 100644

> > >>>> --- a/drivers/core/root.c

> > >>>> +++ b/drivers/core/root.c

> > >>>> @@ -265,9 +265,15 @@ static int dm_scan_fdt_node(struct udevice *parent, const void *blob,

> > >>>>    for (offset = fdt_first_subnode(blob, offset);

> > >>>>         offset > 0;

> > >>>>         offset = fdt_next_subnode(blob, offset)) {

> > >>>> -          /* "chosen" node isn't a device itself but may contain some: */

> > >>>> -          if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {

> > >>>> -                  pr_debug("parsing subnodes of \"chosen\"\n");

> > >>>> +          const char *node_name = fdt_get_name(blob, offset, NULL);

> > >>>> +

> > >>>> +          /*

> > >>>> +           * The "chosen" and "firmware" nodes aren't devices

> > >>>> +           * themselves but may contain some:

> > >>>> +           */

> > >>>> +          if (!strcmp(node_name, "chosen") ||

> > >>>> +              !strcmp(node_name, "firmware")) {

> > >>>> +                  pr_debug("parsing subnodes of \"%s\"\n", node_name);

> > >>>>

> > >>>>                    err = dm_scan_fdt_node(parent, blob, offset,

> > >>>>                                           pre_reloc_only);

> > >>>

> > >>> So, the /firmware node seems special.  Have you talked with the

> > >>> devicetree folks to get it listed in the spec?  That would seem rather

> > >>> valuable for something used by many parties.  Thanks!

> > >>>

> > >>

> > >> some days ago we have sent a patch for this too.

> > >> https://lists.denx.de/pipermail/u-boot/2018-August/338049.html

> > >>

> > >> It is using different way but it should do the same thing.

> > >

> > > OK, so it sounds like in terms of code clean-ups, we need something like

> > > what you reference and then some further clean-ups on top of that

> > > perhaps for other places to call dm_scan_fdt_ofnode_path() for special

> > > cases.  And in terms of formalized specification bits, I do think

> > > /firmware should perhaps get kicked up to the spec itself so that it's

> > > very clear to all consumers.

> >

> > I was also checking latest devicetree spec and there is no record about

> > /firmware node and how it is supposed to be used.

> 

> Patches welcome. :)

> 

> It's really only a container to define non-discoverable firmware

> interfaces. Typically accessed thru a secure call (for ARM) or a

> mailbox. It is primarily just convention rather than a strict

> requirement. We have to support firmware nodes at the top-level too

> anyways.


Right.  To be clear, I'm suggesting that someone (I was thinking Jens)
pop over to the devicetree-spec list and ask about adding _something_
there as "firmware" isn't even on the list of generic names and may even
warrant something in section 3 under base device node types.

-- 
Tom
diff mbox series

Patch

diff --git a/drivers/core/root.c b/drivers/core/root.c
index 72bcc7d7f2a3..0dca507e1187 100644
--- a/drivers/core/root.c
+++ b/drivers/core/root.c
@@ -265,9 +265,15 @@  static int dm_scan_fdt_node(struct udevice *parent, const void *blob,
 	for (offset = fdt_first_subnode(blob, offset);
 	     offset > 0;
 	     offset = fdt_next_subnode(blob, offset)) {
-		/* "chosen" node isn't a device itself but may contain some: */
-		if (!strcmp(fdt_get_name(blob, offset, NULL), "chosen")) {
-			pr_debug("parsing subnodes of \"chosen\"\n");
+		const char *node_name = fdt_get_name(blob, offset, NULL);
+
+		/*
+		 * The "chosen" and "firmware" nodes aren't devices
+		 * themselves but may contain some:
+		 */
+		if (!strcmp(node_name, "chosen") ||
+		    !strcmp(node_name, "firmware")) {
+			pr_debug("parsing subnodes of \"%s\"\n", node_name);
 
 			err = dm_scan_fdt_node(parent, blob, offset,
 					       pre_reloc_only);
@@ -286,8 +292,7 @@  static int dm_scan_fdt_node(struct udevice *parent, const void *blob,
 		err = lists_bind_fdt(parent, offset_to_ofnode(offset), NULL);
 		if (err && !ret) {
 			ret = err;
-			debug("%s: ret=%d\n", fdt_get_name(blob, offset, NULL),
-			      ret);
+			debug("%s: ret=%d\n", node_name, ret);
 		}
 	}