If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
From: Rob Herring <hidden> Date: 2012-08-07 15:19:48
On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote:
quoted hunk
If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
On Tue, Aug 07, 2012 at 20:49:48, Rob Herring wrote:
On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote:
quoted
If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
Adding an additional clkdev lookup accomplishes the same thing and is a
cleaner solution.
That is also required and I have submitted patch for the same -
http://www.spinics.net/lists/arm-kernel/msg187998.html
With DT support, I am getting dev_id as -
- Without "reg" property: d_can.16 and d_can.17,
(I believe it changes dynamically here)
- With "reg" property: 481cc000.d_can and 481d0000.d_can
Which is not so intuitive, I would like to see them as per Spec/TRM, so
doesn't this patch make sense?
Similar thing has already been done for other platforms too.
Thanks,
Vaibhav
Op 7 aug. 2012, om 17:53 heeft "Hiremath, Vaibhav" [off-list ref] het volgende geschreven:
On Tue, Aug 07, 2012 at 20:49:48, Rob Herring wrote:
quoted
On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote:
quoted
If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
{ }
};
+/*
+ * Lookup table for attaching a specific name and platform_data pointer to
+ * devices as they get created by of_platform_populate(). Ideally this table
+ * would not exist, but the current clock implementation depends on some devices
+ * having a specific name OR to satisfy NULL con_id requirement from driver.
+ */
+static const struct of_dev_auxdata am33xx_auxdata_lookup[] __initconst = {
+ OF_DEV_AUXDATA("bosch,d_can", 0x481cc000, "d_can.0", NULL),
+ OF_DEV_AUXDATA("bosch,d_can", 0x481d0000, "d_can.1", NULL),
+ { },
+};
Adding an additional clkdev lookup accomplishes the same thing and is a
cleaner solution.
That is also required and I have submitted patch for the same -
http://www.spinics.net/lists/arm-kernel/msg187998.html
With DT support, I am getting dev_id as -
- Without "reg" property: d_can.16 and d_can.17,
(I believe it changes dynamically here)
- With "reg" property: 481cc000.d_can and 481d0000.d_can
Which is not so intuitive, I would like to see them as per Spec/TRM, so
doesn't this patch make sense?
Similar thing has already been done for other platforms too.
From: Rob Herring <hidden> Date: 2012-08-08 02:08:01
On 08/07/2012 10:53 AM, Hiremath, Vaibhav wrote:
On Tue, Aug 07, 2012 at 20:49:48, Rob Herring wrote:
quoted
On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote:
quoted
If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
That only adds the non-DT name. What I'm saying is you can have 2 lookup
names for the same clock.
With DT support, I am getting dev_id as -
- Without "reg" property: d_can.16 and d_can.17,
(I believe it changes dynamically here)
- With "reg" property: 481cc000.d_can and 481d0000.d_can
Which is not so intuitive, I would like to see them as per Spec/TRM, so
doesn't this patch make sense?
The spec doesn't have a base address for the module? This name is going
to get used in sysfs anyway, and the old name should be going away.
Similar thing has already been done for other platforms too.
On Wed, Aug 08, 2012 at 07:38:01, Rob Herring wrote:
On 08/07/2012 10:53 AM, Hiremath, Vaibhav wrote:
quoted
On Tue, Aug 07, 2012 at 20:49:48, Rob Herring wrote:
quoted
On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote:
quoted
If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
That only adds the non-DT name. What I'm saying is you can have 2 lookup
names for the same clock.
quoted
With DT support, I am getting dev_id as -
- Without "reg" property: d_can.16 and d_can.17,
(I believe it changes dynamically here)
- With "reg" property: 481cc000.d_can and 481d0000.d_can
Which is not so intuitive, I would like to see them as per Spec/TRM, so
doesn't this patch make sense?
The spec doesn't have a base address for the module? This name is going
to get used in sysfs anyway, and the old name should be going away.
This is certainly going to change user interface change, and I thought we
should not change the user interface irrespective of whether it is DT or
non-DT.
Few points, which I do care about, are,
1. request_irq():
For the driver if I am using dev_name(dev) as for the 3rd argument, which
will now different with DT support - brings change in user interface.
Non-DT:
#cat /proc/interrupts
CPU0
52: 0 INTC xxx0
55: 0 INTC xxx1
DT:
#cat /proc/interrupts
CPU0
52: 0 INTC 481cc000.xxx
55: 0 INTC 481d0000.xxx
2. SYSFS:
For example,
Without auxdata:
/sys/devices/481cc000.xxx/
/sys/devices/481d0000.xxx/
With auxdata:
/sys/devices/xxx.0/
/sys/devices/xxx.1/
From user perspective, I still would not want to change the existing
naming convention.
3. Certainly I don't want user to go back to spec everytime to find out
which address is mapped to which instance of module.
Also, in addition to that, in case of SoC's like AM33xx (for that matter,
any embedded SoC) we have different domains and modules are placed in
different domains as per use-cases.
For example, in this case, can0 is places in wakeup domain and can1 is
placed in per-domain. Some boards might use only one instance or some
board might use both of them.
I still would like to keep instance number wherever user interface comes
into picture and populate base address as an additional info to user.
I may be missing something, may be I am not able to see the bigger picture
here.
Grant/Benoit, May be you can conform and put your opinion on this.
Thanks,
Vaibhav
On Wed, Aug 08, 2012 at 07:38:01, Rob Herring wrote:
quoted
On 08/07/2012 10:53 AM, Hiremath, Vaibhav wrote:
quoted
On Tue, Aug 07, 2012 at 20:49:48, Rob Herring wrote:
quoted
On 08/07/2012 08:37 AM, Vaibhav Hiremath wrote:
quoted
If the module requires only one clocksource to function, then
driver can very well call clk_get() api with "con_id = NULL",
clk = clk_get(dev, NULL);
And platform code should respect this and return valid clk handle.
That means, now the clk_get() api would rely on dev_id, and platform
code should either have clk node with matching dev_id (with con_id=NULL)
or return dummy clk node.
With DT support, we can fix the dev_id for particular module
using "struct of_dev_auxdata" to satisfy above clk framework requirement.
In case of AM33XX, we required this for the DCAN module, so this
patch adds "of_dev_auxdata" for both DCAN_0/1 instances.
Signed-off-by: Vaibhav Hiremath <redacted>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Benoit Cousson <redacted>
Cc: Grant Likely <redacted>
---
This patch is boot tested on BeagleBone platform, and checked for
clk_get() return value in d_can module driver.
arch/arm/mach-omap2/board-generic.c | 18 +++++++++++++++++-
1 files changed, 17 insertions(+), 1 deletions(-)
That only adds the non-DT name. What I'm saying is you can have 2 lookup
names for the same clock.
quoted
With DT support, I am getting dev_id as -
- Without "reg" property: d_can.16 and d_can.17,
(I believe it changes dynamically here)
- With "reg" property: 481cc000.d_can and 481d0000.d_can
Which is not so intuitive, I would like to see them as per Spec/TRM, so
doesn't this patch make sense?
The spec doesn't have a base address for the module? This name is going
to get used in sysfs anyway, and the old name should be going away.
This is certainly going to change user interface change, and I thought we
should not change the user interface irrespective of whether it is DT or
non-DT.
Few points, which I do care about, are,
1. request_irq():
For the driver if I am using dev_name(dev) as for the 3rd argument, which
will now different with DT support - brings change in user interface.
Non-DT:
#cat /proc/interrupts
CPU0
52: 0 INTC xxx0
55: 0 INTC xxx1
DT:
#cat /proc/interrupts
CPU0
52: 0 INTC 481cc000.xxx
55: 0 INTC 481d0000.xxx
2. SYSFS:
For example,
Without auxdata:
/sys/devices/481cc000.xxx/
/sys/devices/481d0000.xxx/
With auxdata:
/sys/devices/xxx.0/
/sys/devices/xxx.1/
From user perspective, I still would not want to change the existing
naming convention.
3. Certainly I don't want user to go back to spec everytime to find out
which address is mapped to which instance of module.
Also, in addition to that, in case of SoC's like AM33xx (for that matter,
any embedded SoC) we have different domains and modules are placed in
different domains as per use-cases.
For example, in this case, can0 is places in wakeup domain and can1 is
placed in per-domain. Some boards might use only one instance or some
board might use both of them.
I still would like to keep instance number wherever user interface comes
into picture and populate base address as an additional info to user.
I may be missing something, may be I am not able to see the bigger picture
here.
Grant/Benoit, May be you can conform and put your opinion on this.
Rob,
I think we do not have any conclusion on this, so here should I assume
that I should just simply add another clk node entry in clock-tree, like
below -
CLK("481cc000.d_can", NULL, &dcan0_fck, CK_AM33XX),
CLK("481d0000.d_can", NULL, &dcan1_fck, CK_AM33XX),
Thanks,
Vaibhav