* [RFC RESEND 0/4] ARM: OMAP3+: Add device-tree support for timers
@ 2012-07-13 22:26 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: linux-arm-kernel
This series adds device-tree support for the timers on OMAP3/4 devices. Once
everyone is happy with the implementation I can add support for OMAP2/5 devices
too.
Testing:
- I have tested the all the timers (not used by the kernel as sys-timers) on
both OMAP3430 Beagle and OMAP4460 Panda with/without device-tree with this
series.
- The testing includes
- Configuring, starting a timer and checking the counter value is
incrementing.
- Testing timer overflow interrupt when timer expires.
- Using different clock sources to operate the timer with.
- Using DT to provide resource information for IRQ and memory by
removing Benoit's intention "HACK" in commit a4f6cdb0 (ARM: OMAP:
omap_device: Add omap_device_[alloc|delete] for DT integration)
Jon Hunter (4):
arm/dts: OMAP: Add timer nodes
ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
ARM: OMAP4: Add timer clock aliases for device-tree
ARM: OMAP: Add DT support for timer driver
.../devicetree/bindings/arm/omap/timer.txt | 34 +++++++
arch/arm/boot/dts/omap3.dtsi | 104 ++++++++++++++++++++
arch/arm/boot/dts/omap4.dtsi | 93 +++++++++++++++++
arch/arm/mach-omap2/board-generic.c | 1 +
arch/arm/mach-omap2/clock44xx_data.c | 12 +++
arch/arm/mach-omap2/common.h | 1 +
arch/arm/mach-omap2/timer.c | 40 ++++++++
arch/arm/plat-omap/dmtimer.c | 32 ++++--
8 files changed, 311 insertions(+), 6 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/omap/timer.txt
--
1.7.9.5
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-13 22:26 ` Jon Hunter
@ 2012-07-13 22:26 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley
Cc: Benoit Cousson, linux-omap, linux-arm, device-tree, Jon Hunter
Add the 12 GP timers nodes present in OMAP3.
Add the 11 GP timers nodes present in OMAP4.
Add documentation for timer properties specific to OMAP.
For each timer an alias is being added. The purpose for doing this is because
the OMAP dmtimer driver uses an ID to distinguish between the different timer
instances. For example, a timer can be requested by its ID. By adding an alias
for each timer we can then use the function of_alias_get_id() to extract the
ID for each timer from the alias name. The same method is used for the TTY
serial devices. If it is preferred that such an alias is not added and there
is a better way to pass an ID from device-tree let me know.
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
.../devicetree/bindings/arm/omap/timer.txt | 34 +++++++
arch/arm/boot/dts/omap3.dtsi | 104 ++++++++++++++++++++
arch/arm/boot/dts/omap4.dtsi | 93 +++++++++++++++++
3 files changed, 231 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/omap/timer.txt
diff --git a/Documentation/devicetree/bindings/arm/omap/timer.txt b/Documentation/devicetree/bindings/arm/omap/timer.txt
new file mode 100644
index 0000000..dcbb451
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/omap/timer.txt
@@ -0,0 +1,34 @@
+OMAP Timer controller bindings
+
+Required properties:
+- compatible:
+ - "ti,omap3-timer" for OMAP3+ controllers
+- reg: Contains timer register address range (base address and length)
+- interrupts: Contains the interrupt information for the timer. The format is
+ being dependent on which interrupt controller the OMAP device uses.
+
+OMAP specific properties:
+- ti,hwmods: Name of the hwmod associated to the timer:
+ "timer<X>", <X> being the 1-based instance number from the HW spec
+- ti,timer-alwon: Indicates the timer is in an alway-on power domain.
+- ti,timer-pwm: Indicates the timer supports can generate PWM output.
+- ti,timer-secure: Indicates the timer is reserved on a secure OMAP device and
+ therefore cannot be used by the kernel.
+
+Note: Each timer should have an alias correctly numbered in "aliases" node. The
+ alias is used to identify the timer instance in the driver.
+
+Example:
+
+aliases {
+ timer12 = &timer12;
+};
+
+timer12: timer@48304000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48304000 0xfff>;
+ interrupts = <95>;
+ ti,hwmods = "timer12"
+ ti,timer-alwon;
+ ti,timer-secure;
+};
diff --git a/arch/arm/boot/dts/omap3.dtsi b/arch/arm/boot/dts/omap3.dtsi
index 8109471..f309f2a 100644
--- a/arch/arm/boot/dts/omap3.dtsi
+++ b/arch/arm/boot/dts/omap3.dtsi
@@ -12,12 +12,25 @@
/ {
compatible = "ti,omap3430", "ti,omap3";
+ interrupt-parent = <&intc>;
aliases {
serial0 = &uart1;
serial1 = &uart2;
serial2 = &uart3;
serial3 = &uart4;
+ timer1 = &timer1;
+ timer2 = &timer2;
+ timer3 = &timer3;
+ timer4 = &timer4;
+ timer5 = &timer5;
+ timer6 = &timer6;
+ timer7 = &timer7;
+ timer8 = &timer8;
+ timer9 = &timer9;
+ timer10 = &timer10;
+ timer11 = &timer11;
+ timer12 = &timer12;
};
cpus {
@@ -220,5 +233,96 @@
compatible = "ti,omap3-wdt";
ti,hwmods = "wd_timer2";
};
+
+ timer1: timer@48318000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48318000 0xfff>;
+ interrupts = <37>;
+ ti,hwmods = "timer1";
+ ti,timer-alwon;
+ };
+
+ timer2: timer@49032000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49032000 0xfff>;
+ interrupts = <38>;
+ ti,hwmods = "timer2";
+ };
+
+ timer3: timer@49034000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49034000 0xfff>;
+ interrupts = <39>;
+ ti,hwmods = "timer3";
+ };
+
+ timer4: timer@49036000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49036000 0xfff>;
+ interrupts = <40>;
+ ti,hwmods = "timer4";
+ };
+
+ timer5: timer@49038000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49038000 0xfff>;
+ interrupts = <41>;
+ ti,hwmods = "timer5";
+ };
+
+ timer6: timer@4903a000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903a000 0xfff>;
+ interrupts = <42>;
+ ti,hwmods = "timer6";
+ };
+
+ timer7: timer@4903c000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903c000 0xfff>;
+ interrupts = <43>;
+ ti,hwmods = "timer7";
+ };
+
+ timer8: timer@4903e000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903e000 0xfff>;
+ interrupts = <44>;
+ ti,hwmods = "timer8";
+ ti,timer-pwm;
+ };
+
+ timer9: timer@49040000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49040000 0xfff>;
+ interrupts = <45>;
+ ti,hwmods = "timer9";
+ ti,timer-pwm;
+ };
+
+ timer10: timer@48086000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48086000 0xfff>;
+ interrupts = <46>;
+ ti,hwmods = "timer10";
+ ti,timer-pwm;
+ };
+
+ timer11: timer@48088000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48088000 0xfff>;
+ interrupts = <47>;
+ ti,hwmods = "timer11";
+ ti,timer-pwm;
+ };
+
+ timer12: timer@48304000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48304000 0xfff>;
+ interrupts = <95>;
+ ti,hwmods = "timer12";
+ ti,timer-alwon;
+ ti,timer-secure;
+ };
};
};
diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
index 04cbbcb..39716c5 100644
--- a/arch/arm/boot/dts/omap4.dtsi
+++ b/arch/arm/boot/dts/omap4.dtsi
@@ -25,6 +25,17 @@
serial1 = &uart2;
serial2 = &uart3;
serial3 = &uart4;
+ timer1 = &timer1;
+ timer2 = &timer2;
+ timer3 = &timer3;
+ timer4 = &timer4;
+ timer5 = &timer5;
+ timer6 = &timer6;
+ timer7 = &timer7;
+ timer8 = &timer8;
+ timer9 = &timer9;
+ timer10 = &timer10;
+ timer11 = &timer11;
};
cpus {
@@ -295,5 +306,87 @@
interrupt-parent = <&gic>;
ti,hwmods = "dmic";
};
+
+ timer1: timer@4a318000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4a318000 0x7f>;
+ interrupts = <0 37 0x4>;
+ ti,hwmods = "timer1";
+ ti,timer-alwon;
+ };
+
+ timer2: timer@48032000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48032000 0x7f>;
+ interrupts = <0 38 0x4>;
+ ti,hwmods = "timer2";
+ };
+
+ timer3: timer@48034000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48034000 0x7f>;
+ interrupts = <0 39 0x4>;
+ ti,hwmods = "timer3";
+ };
+
+ timer4: timer@48036000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48036000 0x7f>;
+ interrupts = <0 40 0x4>;
+ ti,hwmods = "timer4";
+ };
+
+ timer5: timer@49038000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49038000 0x7f>;
+ interrupts = <0 41 0x4>;
+ ti,hwmods = "timer5";
+ };
+
+ timer6: timer@4903a000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903a000 0x7f>;
+ interrupts = <0 42 0x4>;
+ ti,hwmods = "timer6";
+ };
+
+ timer7: timer@4903c000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903c000 0x7f>;
+ interrupts = <0 43 0x4>;
+ ti,hwmods = "timer7";
+ };
+
+ timer8: timer@4903e000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903e000 0x7f>;
+ interrupts = <0 44 0x4>;
+ ti,hwmods = "timer8";
+ ti,timer-pwm;
+ };
+
+ timer9: timer@4803e000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4803e000 0x7f>;
+ interrupts = <0 45 0x4>;
+ ti,hwmods = "timer9";
+ ti,timer-pwm;
+ };
+
+ timer10: timer@48086000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48086000 0x7f>;
+ interrupts = <0 46 0x4>;
+ ti,hwmods = "timer10";
+ ti,timer-pwm;
+ };
+
+ timer11: timer@48088000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48088000 0x7f>;
+ interrupts = <0 47 0x4>;
+ ti,hwmods = "timer11";
+ ti,timer-pwm;
+ };
};
};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-13 22:26 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: linux-arm-kernel
Add the 12 GP timers nodes present in OMAP3.
Add the 11 GP timers nodes present in OMAP4.
Add documentation for timer properties specific to OMAP.
For each timer an alias is being added. The purpose for doing this is because
the OMAP dmtimer driver uses an ID to distinguish between the different timer
instances. For example, a timer can be requested by its ID. By adding an alias
for each timer we can then use the function of_alias_get_id() to extract the
ID for each timer from the alias name. The same method is used for the TTY
serial devices. If it is preferred that such an alias is not added and there
is a better way to pass an ID from device-tree let me know.
Cc: Benoit Cousson <b-cousson@ti.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
.../devicetree/bindings/arm/omap/timer.txt | 34 +++++++
arch/arm/boot/dts/omap3.dtsi | 104 ++++++++++++++++++++
arch/arm/boot/dts/omap4.dtsi | 93 +++++++++++++++++
3 files changed, 231 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/omap/timer.txt
diff --git a/Documentation/devicetree/bindings/arm/omap/timer.txt b/Documentation/devicetree/bindings/arm/omap/timer.txt
new file mode 100644
index 0000000..dcbb451
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/omap/timer.txt
@@ -0,0 +1,34 @@
+OMAP Timer controller bindings
+
+Required properties:
+- compatible:
+ - "ti,omap3-timer" for OMAP3+ controllers
+- reg: Contains timer register address range (base address and length)
+- interrupts: Contains the interrupt information for the timer. The format is
+ being dependent on which interrupt controller the OMAP device uses.
+
+OMAP specific properties:
+- ti,hwmods: Name of the hwmod associated to the timer:
+ "timer<X>", <X> being the 1-based instance number from the HW spec
+- ti,timer-alwon: Indicates the timer is in an alway-on power domain.
+- ti,timer-pwm: Indicates the timer supports can generate PWM output.
+- ti,timer-secure: Indicates the timer is reserved on a secure OMAP device and
+ therefore cannot be used by the kernel.
+
+Note: Each timer should have an alias correctly numbered in "aliases" node. The
+ alias is used to identify the timer instance in the driver.
+
+Example:
+
+aliases {
+ timer12 = &timer12;
+};
+
+timer12: timer at 48304000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48304000 0xfff>;
+ interrupts = <95>;
+ ti,hwmods = "timer12"
+ ti,timer-alwon;
+ ti,timer-secure;
+};
diff --git a/arch/arm/boot/dts/omap3.dtsi b/arch/arm/boot/dts/omap3.dtsi
index 8109471..f309f2a 100644
--- a/arch/arm/boot/dts/omap3.dtsi
+++ b/arch/arm/boot/dts/omap3.dtsi
@@ -12,12 +12,25 @@
/ {
compatible = "ti,omap3430", "ti,omap3";
+ interrupt-parent = <&intc>;
aliases {
serial0 = &uart1;
serial1 = &uart2;
serial2 = &uart3;
serial3 = &uart4;
+ timer1 = &timer1;
+ timer2 = &timer2;
+ timer3 = &timer3;
+ timer4 = &timer4;
+ timer5 = &timer5;
+ timer6 = &timer6;
+ timer7 = &timer7;
+ timer8 = &timer8;
+ timer9 = &timer9;
+ timer10 = &timer10;
+ timer11 = &timer11;
+ timer12 = &timer12;
};
cpus {
@@ -220,5 +233,96 @@
compatible = "ti,omap3-wdt";
ti,hwmods = "wd_timer2";
};
+
+ timer1: timer at 48318000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48318000 0xfff>;
+ interrupts = <37>;
+ ti,hwmods = "timer1";
+ ti,timer-alwon;
+ };
+
+ timer2: timer at 49032000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49032000 0xfff>;
+ interrupts = <38>;
+ ti,hwmods = "timer2";
+ };
+
+ timer3: timer at 49034000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49034000 0xfff>;
+ interrupts = <39>;
+ ti,hwmods = "timer3";
+ };
+
+ timer4: timer at 49036000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49036000 0xfff>;
+ interrupts = <40>;
+ ti,hwmods = "timer4";
+ };
+
+ timer5: timer at 49038000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49038000 0xfff>;
+ interrupts = <41>;
+ ti,hwmods = "timer5";
+ };
+
+ timer6: timer at 4903a000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903a000 0xfff>;
+ interrupts = <42>;
+ ti,hwmods = "timer6";
+ };
+
+ timer7: timer at 4903c000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903c000 0xfff>;
+ interrupts = <43>;
+ ti,hwmods = "timer7";
+ };
+
+ timer8: timer at 4903e000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903e000 0xfff>;
+ interrupts = <44>;
+ ti,hwmods = "timer8";
+ ti,timer-pwm;
+ };
+
+ timer9: timer at 49040000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49040000 0xfff>;
+ interrupts = <45>;
+ ti,hwmods = "timer9";
+ ti,timer-pwm;
+ };
+
+ timer10: timer at 48086000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48086000 0xfff>;
+ interrupts = <46>;
+ ti,hwmods = "timer10";
+ ti,timer-pwm;
+ };
+
+ timer11: timer at 48088000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48088000 0xfff>;
+ interrupts = <47>;
+ ti,hwmods = "timer11";
+ ti,timer-pwm;
+ };
+
+ timer12: timer at 48304000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48304000 0xfff>;
+ interrupts = <95>;
+ ti,hwmods = "timer12";
+ ti,timer-alwon;
+ ti,timer-secure;
+ };
};
};
diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
index 04cbbcb..39716c5 100644
--- a/arch/arm/boot/dts/omap4.dtsi
+++ b/arch/arm/boot/dts/omap4.dtsi
@@ -25,6 +25,17 @@
serial1 = &uart2;
serial2 = &uart3;
serial3 = &uart4;
+ timer1 = &timer1;
+ timer2 = &timer2;
+ timer3 = &timer3;
+ timer4 = &timer4;
+ timer5 = &timer5;
+ timer6 = &timer6;
+ timer7 = &timer7;
+ timer8 = &timer8;
+ timer9 = &timer9;
+ timer10 = &timer10;
+ timer11 = &timer11;
};
cpus {
@@ -295,5 +306,87 @@
interrupt-parent = <&gic>;
ti,hwmods = "dmic";
};
+
+ timer1: timer at 4a318000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4a318000 0x7f>;
+ interrupts = <0 37 0x4>;
+ ti,hwmods = "timer1";
+ ti,timer-alwon;
+ };
+
+ timer2: timer at 48032000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48032000 0x7f>;
+ interrupts = <0 38 0x4>;
+ ti,hwmods = "timer2";
+ };
+
+ timer3: timer at 48034000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48034000 0x7f>;
+ interrupts = <0 39 0x4>;
+ ti,hwmods = "timer3";
+ };
+
+ timer4: timer at 48036000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48036000 0x7f>;
+ interrupts = <0 40 0x4>;
+ ti,hwmods = "timer4";
+ };
+
+ timer5: timer at 49038000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x49038000 0x7f>;
+ interrupts = <0 41 0x4>;
+ ti,hwmods = "timer5";
+ };
+
+ timer6: timer at 4903a000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903a000 0x7f>;
+ interrupts = <0 42 0x4>;
+ ti,hwmods = "timer6";
+ };
+
+ timer7: timer at 4903c000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903c000 0x7f>;
+ interrupts = <0 43 0x4>;
+ ti,hwmods = "timer7";
+ };
+
+ timer8: timer at 4903e000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4903e000 0x7f>;
+ interrupts = <0 44 0x4>;
+ ti,hwmods = "timer8";
+ ti,timer-pwm;
+ };
+
+ timer9: timer at 4803e000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x4803e000 0x7f>;
+ interrupts = <0 45 0x4>;
+ ti,hwmods = "timer9";
+ ti,timer-pwm;
+ };
+
+ timer10: timer at 48086000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48086000 0x7f>;
+ interrupts = <0 46 0x4>;
+ ti,hwmods = "timer10";
+ ti,timer-pwm;
+ };
+
+ timer11: timer at 48088000 {
+ compatible = "ti,omap3-timer";
+ reg = <0x48088000 0x7f>;
+ interrupts = <0 47 0x4>;
+ ti,hwmods = "timer11";
+ ti,timer-pwm;
+ };
};
};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-13 22:26 ` Jon Hunter
@ 2012-07-14 2:15 ` Rob Herring
-1 siblings, 0 replies; 65+ messages in thread
From: Rob Herring @ 2012-07-14 2:15 UTC (permalink / raw)
To: Jon Hunter
Cc: Tarun Kanti DebBarma, Tony Lindgren, Grant Likely, Paul Walmsley,
Benoit Cousson, linux-omap, linux-arm, device-tree
On 07/13/2012 05:26 PM, Jon Hunter wrote:
> Add the 12 GP timers nodes present in OMAP3.
> Add the 11 GP timers nodes present in OMAP4.
>
> Add documentation for timer properties specific to OMAP.
>
> For each timer an alias is being added. The purpose for doing this is because
> the OMAP dmtimer driver uses an ID to distinguish between the different timer
> instances. For example, a timer can be requested by its ID. By adding an alias
> for each timer we can then use the function of_alias_get_id() to extract the
> ID for each timer from the alias name. The same method is used for the TTY
> serial devices. If it is preferred that such an alias is not added and there
> is a better way to pass an ID from device-tree let me know.
I'm not sure this is really a good use of aliases. UARTs use aliases
because it is important that the UART number to tty number is known and
fixed. IIUC, as an example you are picking timer1 because it has
properties X, Y and Z. If so, then you should describe those h/w
properties within the timer nodes so you can pick which timer to use
based on it's h/w properties.
Rob
>
> Cc: Benoit Cousson <b-cousson@ti.com>
> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> ---
> .../devicetree/bindings/arm/omap/timer.txt | 34 +++++++
> arch/arm/boot/dts/omap3.dtsi | 104 ++++++++++++++++++++
> arch/arm/boot/dts/omap4.dtsi | 93 +++++++++++++++++
> 3 files changed, 231 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/arm/omap/timer.txt
>
> diff --git a/Documentation/devicetree/bindings/arm/omap/timer.txt b/Documentation/devicetree/bindings/arm/omap/timer.txt
> new file mode 100644
> index 0000000..dcbb451
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/omap/timer.txt
> @@ -0,0 +1,34 @@
> +OMAP Timer controller bindings
> +
> +Required properties:
> +- compatible:
> + - "ti,omap3-timer" for OMAP3+ controllers
> +- reg: Contains timer register address range (base address and length)
> +- interrupts: Contains the interrupt information for the timer. The format is
> + being dependent on which interrupt controller the OMAP device uses.
> +
> +OMAP specific properties:
> +- ti,hwmods: Name of the hwmod associated to the timer:
> + "timer<X>", <X> being the 1-based instance number from the HW spec
> +- ti,timer-alwon: Indicates the timer is in an alway-on power domain.
> +- ti,timer-pwm: Indicates the timer supports can generate PWM output.
> +- ti,timer-secure: Indicates the timer is reserved on a secure OMAP device and
> + therefore cannot be used by the kernel.
> +
> +Note: Each timer should have an alias correctly numbered in "aliases" node. The
> + alias is used to identify the timer instance in the driver.
> +
> +Example:
> +
> +aliases {
> + timer12 = &timer12;
> +};
> +
> +timer12: timer@48304000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48304000 0xfff>;
> + interrupts = <95>;
> + ti,hwmods = "timer12"
> + ti,timer-alwon;
> + ti,timer-secure;
> +};
> diff --git a/arch/arm/boot/dts/omap3.dtsi b/arch/arm/boot/dts/omap3.dtsi
> index 8109471..f309f2a 100644
> --- a/arch/arm/boot/dts/omap3.dtsi
> +++ b/arch/arm/boot/dts/omap3.dtsi
> @@ -12,12 +12,25 @@
>
> / {
> compatible = "ti,omap3430", "ti,omap3";
> + interrupt-parent = <&intc>;
>
> aliases {
> serial0 = &uart1;
> serial1 = &uart2;
> serial2 = &uart3;
> serial3 = &uart4;
> + timer1 = &timer1;
> + timer2 = &timer2;
> + timer3 = &timer3;
> + timer4 = &timer4;
> + timer5 = &timer5;
> + timer6 = &timer6;
> + timer7 = &timer7;
> + timer8 = &timer8;
> + timer9 = &timer9;
> + timer10 = &timer10;
> + timer11 = &timer11;
> + timer12 = &timer12;
> };
>
> cpus {
> @@ -220,5 +233,96 @@
> compatible = "ti,omap3-wdt";
> ti,hwmods = "wd_timer2";
> };
> +
> + timer1: timer@48318000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48318000 0xfff>;
> + interrupts = <37>;
> + ti,hwmods = "timer1";
> + ti,timer-alwon;
> + };
> +
> + timer2: timer@49032000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49032000 0xfff>;
> + interrupts = <38>;
> + ti,hwmods = "timer2";
> + };
> +
> + timer3: timer@49034000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49034000 0xfff>;
> + interrupts = <39>;
> + ti,hwmods = "timer3";
> + };
> +
> + timer4: timer@49036000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49036000 0xfff>;
> + interrupts = <40>;
> + ti,hwmods = "timer4";
> + };
> +
> + timer5: timer@49038000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49038000 0xfff>;
> + interrupts = <41>;
> + ti,hwmods = "timer5";
> + };
> +
> + timer6: timer@4903a000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903a000 0xfff>;
> + interrupts = <42>;
> + ti,hwmods = "timer6";
> + };
> +
> + timer7: timer@4903c000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903c000 0xfff>;
> + interrupts = <43>;
> + ti,hwmods = "timer7";
> + };
> +
> + timer8: timer@4903e000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903e000 0xfff>;
> + interrupts = <44>;
> + ti,hwmods = "timer8";
> + ti,timer-pwm;
> + };
> +
> + timer9: timer@49040000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49040000 0xfff>;
> + interrupts = <45>;
> + ti,hwmods = "timer9";
> + ti,timer-pwm;
> + };
> +
> + timer10: timer@48086000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48086000 0xfff>;
> + interrupts = <46>;
> + ti,hwmods = "timer10";
> + ti,timer-pwm;
> + };
> +
> + timer11: timer@48088000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48088000 0xfff>;
> + interrupts = <47>;
> + ti,hwmods = "timer11";
> + ti,timer-pwm;
> + };
> +
> + timer12: timer@48304000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48304000 0xfff>;
> + interrupts = <95>;
> + ti,hwmods = "timer12";
> + ti,timer-alwon;
> + ti,timer-secure;
> + };
> };
> };
> diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
> index 04cbbcb..39716c5 100644
> --- a/arch/arm/boot/dts/omap4.dtsi
> +++ b/arch/arm/boot/dts/omap4.dtsi
> @@ -25,6 +25,17 @@
> serial1 = &uart2;
> serial2 = &uart3;
> serial3 = &uart4;
> + timer1 = &timer1;
> + timer2 = &timer2;
> + timer3 = &timer3;
> + timer4 = &timer4;
> + timer5 = &timer5;
> + timer6 = &timer6;
> + timer7 = &timer7;
> + timer8 = &timer8;
> + timer9 = &timer9;
> + timer10 = &timer10;
> + timer11 = &timer11;
> };
>
> cpus {
> @@ -295,5 +306,87 @@
> interrupt-parent = <&gic>;
> ti,hwmods = "dmic";
> };
> +
> + timer1: timer@4a318000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4a318000 0x7f>;
> + interrupts = <0 37 0x4>;
> + ti,hwmods = "timer1";
> + ti,timer-alwon;
> + };
> +
> + timer2: timer@48032000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48032000 0x7f>;
> + interrupts = <0 38 0x4>;
> + ti,hwmods = "timer2";
> + };
> +
> + timer3: timer@48034000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48034000 0x7f>;
> + interrupts = <0 39 0x4>;
> + ti,hwmods = "timer3";
> + };
> +
> + timer4: timer@48036000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48036000 0x7f>;
> + interrupts = <0 40 0x4>;
> + ti,hwmods = "timer4";
> + };
> +
> + timer5: timer@49038000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49038000 0x7f>;
> + interrupts = <0 41 0x4>;
> + ti,hwmods = "timer5";
> + };
> +
> + timer6: timer@4903a000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903a000 0x7f>;
> + interrupts = <0 42 0x4>;
> + ti,hwmods = "timer6";
> + };
> +
> + timer7: timer@4903c000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903c000 0x7f>;
> + interrupts = <0 43 0x4>;
> + ti,hwmods = "timer7";
> + };
> +
> + timer8: timer@4903e000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903e000 0x7f>;
> + interrupts = <0 44 0x4>;
> + ti,hwmods = "timer8";
> + ti,timer-pwm;
> + };
> +
> + timer9: timer@4803e000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4803e000 0x7f>;
> + interrupts = <0 45 0x4>;
> + ti,hwmods = "timer9";
> + ti,timer-pwm;
> + };
> +
> + timer10: timer@48086000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48086000 0x7f>;
> + interrupts = <0 46 0x4>;
> + ti,hwmods = "timer10";
> + ti,timer-pwm;
> + };
> +
> + timer11: timer@48088000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48088000 0x7f>;
> + interrupts = <0 47 0x4>;
> + ti,hwmods = "timer11";
> + ti,timer-pwm;
> + };
> };
> };
>
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-14 2:15 ` Rob Herring
0 siblings, 0 replies; 65+ messages in thread
From: Rob Herring @ 2012-07-14 2:15 UTC (permalink / raw)
To: linux-arm-kernel
On 07/13/2012 05:26 PM, Jon Hunter wrote:
> Add the 12 GP timers nodes present in OMAP3.
> Add the 11 GP timers nodes present in OMAP4.
>
> Add documentation for timer properties specific to OMAP.
>
> For each timer an alias is being added. The purpose for doing this is because
> the OMAP dmtimer driver uses an ID to distinguish between the different timer
> instances. For example, a timer can be requested by its ID. By adding an alias
> for each timer we can then use the function of_alias_get_id() to extract the
> ID for each timer from the alias name. The same method is used for the TTY
> serial devices. If it is preferred that such an alias is not added and there
> is a better way to pass an ID from device-tree let me know.
I'm not sure this is really a good use of aliases. UARTs use aliases
because it is important that the UART number to tty number is known and
fixed. IIUC, as an example you are picking timer1 because it has
properties X, Y and Z. If so, then you should describe those h/w
properties within the timer nodes so you can pick which timer to use
based on it's h/w properties.
Rob
>
> Cc: Benoit Cousson <b-cousson@ti.com>
> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> ---
> .../devicetree/bindings/arm/omap/timer.txt | 34 +++++++
> arch/arm/boot/dts/omap3.dtsi | 104 ++++++++++++++++++++
> arch/arm/boot/dts/omap4.dtsi | 93 +++++++++++++++++
> 3 files changed, 231 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/arm/omap/timer.txt
>
> diff --git a/Documentation/devicetree/bindings/arm/omap/timer.txt b/Documentation/devicetree/bindings/arm/omap/timer.txt
> new file mode 100644
> index 0000000..dcbb451
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/omap/timer.txt
> @@ -0,0 +1,34 @@
> +OMAP Timer controller bindings
> +
> +Required properties:
> +- compatible:
> + - "ti,omap3-timer" for OMAP3+ controllers
> +- reg: Contains timer register address range (base address and length)
> +- interrupts: Contains the interrupt information for the timer. The format is
> + being dependent on which interrupt controller the OMAP device uses.
> +
> +OMAP specific properties:
> +- ti,hwmods: Name of the hwmod associated to the timer:
> + "timer<X>", <X> being the 1-based instance number from the HW spec
> +- ti,timer-alwon: Indicates the timer is in an alway-on power domain.
> +- ti,timer-pwm: Indicates the timer supports can generate PWM output.
> +- ti,timer-secure: Indicates the timer is reserved on a secure OMAP device and
> + therefore cannot be used by the kernel.
> +
> +Note: Each timer should have an alias correctly numbered in "aliases" node. The
> + alias is used to identify the timer instance in the driver.
> +
> +Example:
> +
> +aliases {
> + timer12 = &timer12;
> +};
> +
> +timer12: timer at 48304000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48304000 0xfff>;
> + interrupts = <95>;
> + ti,hwmods = "timer12"
> + ti,timer-alwon;
> + ti,timer-secure;
> +};
> diff --git a/arch/arm/boot/dts/omap3.dtsi b/arch/arm/boot/dts/omap3.dtsi
> index 8109471..f309f2a 100644
> --- a/arch/arm/boot/dts/omap3.dtsi
> +++ b/arch/arm/boot/dts/omap3.dtsi
> @@ -12,12 +12,25 @@
>
> / {
> compatible = "ti,omap3430", "ti,omap3";
> + interrupt-parent = <&intc>;
>
> aliases {
> serial0 = &uart1;
> serial1 = &uart2;
> serial2 = &uart3;
> serial3 = &uart4;
> + timer1 = &timer1;
> + timer2 = &timer2;
> + timer3 = &timer3;
> + timer4 = &timer4;
> + timer5 = &timer5;
> + timer6 = &timer6;
> + timer7 = &timer7;
> + timer8 = &timer8;
> + timer9 = &timer9;
> + timer10 = &timer10;
> + timer11 = &timer11;
> + timer12 = &timer12;
> };
>
> cpus {
> @@ -220,5 +233,96 @@
> compatible = "ti,omap3-wdt";
> ti,hwmods = "wd_timer2";
> };
> +
> + timer1: timer at 48318000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48318000 0xfff>;
> + interrupts = <37>;
> + ti,hwmods = "timer1";
> + ti,timer-alwon;
> + };
> +
> + timer2: timer at 49032000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49032000 0xfff>;
> + interrupts = <38>;
> + ti,hwmods = "timer2";
> + };
> +
> + timer3: timer at 49034000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49034000 0xfff>;
> + interrupts = <39>;
> + ti,hwmods = "timer3";
> + };
> +
> + timer4: timer at 49036000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49036000 0xfff>;
> + interrupts = <40>;
> + ti,hwmods = "timer4";
> + };
> +
> + timer5: timer at 49038000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49038000 0xfff>;
> + interrupts = <41>;
> + ti,hwmods = "timer5";
> + };
> +
> + timer6: timer at 4903a000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903a000 0xfff>;
> + interrupts = <42>;
> + ti,hwmods = "timer6";
> + };
> +
> + timer7: timer at 4903c000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903c000 0xfff>;
> + interrupts = <43>;
> + ti,hwmods = "timer7";
> + };
> +
> + timer8: timer at 4903e000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903e000 0xfff>;
> + interrupts = <44>;
> + ti,hwmods = "timer8";
> + ti,timer-pwm;
> + };
> +
> + timer9: timer at 49040000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49040000 0xfff>;
> + interrupts = <45>;
> + ti,hwmods = "timer9";
> + ti,timer-pwm;
> + };
> +
> + timer10: timer at 48086000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48086000 0xfff>;
> + interrupts = <46>;
> + ti,hwmods = "timer10";
> + ti,timer-pwm;
> + };
> +
> + timer11: timer at 48088000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48088000 0xfff>;
> + interrupts = <47>;
> + ti,hwmods = "timer11";
> + ti,timer-pwm;
> + };
> +
> + timer12: timer at 48304000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48304000 0xfff>;
> + interrupts = <95>;
> + ti,hwmods = "timer12";
> + ti,timer-alwon;
> + ti,timer-secure;
> + };
> };
> };
> diff --git a/arch/arm/boot/dts/omap4.dtsi b/arch/arm/boot/dts/omap4.dtsi
> index 04cbbcb..39716c5 100644
> --- a/arch/arm/boot/dts/omap4.dtsi
> +++ b/arch/arm/boot/dts/omap4.dtsi
> @@ -25,6 +25,17 @@
> serial1 = &uart2;
> serial2 = &uart3;
> serial3 = &uart4;
> + timer1 = &timer1;
> + timer2 = &timer2;
> + timer3 = &timer3;
> + timer4 = &timer4;
> + timer5 = &timer5;
> + timer6 = &timer6;
> + timer7 = &timer7;
> + timer8 = &timer8;
> + timer9 = &timer9;
> + timer10 = &timer10;
> + timer11 = &timer11;
> };
>
> cpus {
> @@ -295,5 +306,87 @@
> interrupt-parent = <&gic>;
> ti,hwmods = "dmic";
> };
> +
> + timer1: timer at 4a318000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4a318000 0x7f>;
> + interrupts = <0 37 0x4>;
> + ti,hwmods = "timer1";
> + ti,timer-alwon;
> + };
> +
> + timer2: timer at 48032000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48032000 0x7f>;
> + interrupts = <0 38 0x4>;
> + ti,hwmods = "timer2";
> + };
> +
> + timer3: timer at 48034000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48034000 0x7f>;
> + interrupts = <0 39 0x4>;
> + ti,hwmods = "timer3";
> + };
> +
> + timer4: timer at 48036000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48036000 0x7f>;
> + interrupts = <0 40 0x4>;
> + ti,hwmods = "timer4";
> + };
> +
> + timer5: timer at 49038000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x49038000 0x7f>;
> + interrupts = <0 41 0x4>;
> + ti,hwmods = "timer5";
> + };
> +
> + timer6: timer at 4903a000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903a000 0x7f>;
> + interrupts = <0 42 0x4>;
> + ti,hwmods = "timer6";
> + };
> +
> + timer7: timer at 4903c000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903c000 0x7f>;
> + interrupts = <0 43 0x4>;
> + ti,hwmods = "timer7";
> + };
> +
> + timer8: timer at 4903e000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4903e000 0x7f>;
> + interrupts = <0 44 0x4>;
> + ti,hwmods = "timer8";
> + ti,timer-pwm;
> + };
> +
> + timer9: timer at 4803e000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x4803e000 0x7f>;
> + interrupts = <0 45 0x4>;
> + ti,hwmods = "timer9";
> + ti,timer-pwm;
> + };
> +
> + timer10: timer at 48086000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48086000 0x7f>;
> + interrupts = <0 46 0x4>;
> + ti,hwmods = "timer10";
> + ti,timer-pwm;
> + };
> +
> + timer11: timer at 48088000 {
> + compatible = "ti,omap3-timer";
> + reg = <0x48088000 0x7f>;
> + interrupts = <0 47 0x4>;
> + ti,hwmods = "timer11";
> + ti,timer-pwm;
> + };
> };
> };
>
^ permalink raw reply [flat|nested] 65+ messages in thread[parent not found: <5000D647.4090200-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]
* Mis?use of aliases
[not found] ` <5000D647.4090200-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
@ 2012-07-14 5:30 ` Mitch Bradley
[not found] ` <50010402.3050502-D5eQfiDGL7eakBO8gow8eQ@public.gmane.org>
2012-07-14 6:56 ` Paul Walmsley
1 sibling, 1 reply; 65+ messages in thread
From: Mitch Bradley @ 2012-07-14 5:30 UTC (permalink / raw)
To: Rob Herring; +Cc: device-tree, linux-omap, linux-arm, Tarun Kanti DebBarma
> I'm not sure this is really a good use of aliases. UARTs use aliases
> because it is important that the UART number to tty number is known and
> fixed.
This brings up an issue that I've been meaning to comment on.
The use of phandle-valued properties in the aliases node causes real OFW
implementations some amount of heartburn. The Open Firmware standard
says that the properties in /aliases are string-valued. That's
important, because aliases are shorthand for fragments of full device
specifiers (pathnames that can include arguments to nodes). Phandles
can point to nodes, but can't be relative, and can't encode
per-node-component arguments.
For binding a Linux unit number to a device node, I would prefer to
decorate the node with a property like "linux,unit#", instead of
breaking the standard semantics of /aliases.
Mitch
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-14 2:15 ` Rob Herring
@ 2012-07-14 6:56 ` Paul Walmsley
-1 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-14 6:56 UTC (permalink / raw)
To: Rob Herring; +Cc: device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
Hi
On Fri, 13 Jul 2012, Rob Herring wrote:
> I'm not sure this is really a good use of aliases. UARTs use aliases
> because it is important that the UART number to tty number is known and
> fixed. IIUC, as an example you are picking timer1 because it has
> properties X, Y and Z. If so, then you should describe those h/w
> properties within the timer nodes so you can pick which timer to use
> based on it's h/w properties.
Some GPTIMER blocks have input and output signals that can be routed to
external package balls. So it's possible that some application may need
to request a specific timer ID, since that timer would be connected to a
specific off-chip device.
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-14 6:56 ` Paul Walmsley
0 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-14 6:56 UTC (permalink / raw)
To: linux-arm-kernel
Hi
On Fri, 13 Jul 2012, Rob Herring wrote:
> I'm not sure this is really a good use of aliases. UARTs use aliases
> because it is important that the UART number to tty number is known and
> fixed. IIUC, as an example you are picking timer1 because it has
> properties X, Y and Z. If so, then you should describe those h/w
> properties within the timer nodes so you can pick which timer to use
> based on it's h/w properties.
Some GPTIMER blocks have input and output signals that can be routed to
external package balls. So it's possible that some application may need
to request a specific timer ID, since that timer would be connected to a
specific off-chip device.
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-14 6:56 ` Paul Walmsley
@ 2012-07-14 14:01 ` Rob Herring
-1 siblings, 0 replies; 65+ messages in thread
From: Rob Herring @ 2012-07-14 14:01 UTC (permalink / raw)
To: Paul Walmsley
Cc: Jon Hunter, Tarun Kanti DebBarma, Tony Lindgren, Grant Likely,
Benoit Cousson, linux-omap, linux-arm, device-tree
On 07/14/2012 01:56 AM, Paul Walmsley wrote:
> Hi
>
> On Fri, 13 Jul 2012, Rob Herring wrote:
>
>> I'm not sure this is really a good use of aliases. UARTs use aliases
>> because it is important that the UART number to tty number is known and
>> fixed. IIUC, as an example you are picking timer1 because it has
>> properties X, Y and Z. If so, then you should describe those h/w
>> properties within the timer nodes so you can pick which timer to use
>> based on it's h/w properties.
>
> Some GPTIMER blocks have input and output signals that can be routed to
> external package balls. So it's possible that some application may need
> to request a specific timer ID, since that timer would be connected to a
> specific off-chip device.
Yes, I understand that. So you should be describing which ones have i/o
and what they are connected to. The PWM binding is probably a starting
point.
Rob
>
>
> - Paul
>
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-14 14:01 ` Rob Herring
0 siblings, 0 replies; 65+ messages in thread
From: Rob Herring @ 2012-07-14 14:01 UTC (permalink / raw)
To: linux-arm-kernel
On 07/14/2012 01:56 AM, Paul Walmsley wrote:
> Hi
>
> On Fri, 13 Jul 2012, Rob Herring wrote:
>
>> I'm not sure this is really a good use of aliases. UARTs use aliases
>> because it is important that the UART number to tty number is known and
>> fixed. IIUC, as an example you are picking timer1 because it has
>> properties X, Y and Z. If so, then you should describe those h/w
>> properties within the timer nodes so you can pick which timer to use
>> based on it's h/w properties.
>
> Some GPTIMER blocks have input and output signals that can be routed to
> external package balls. So it's possible that some application may need
> to request a specific timer ID, since that timer would be connected to a
> specific off-chip device.
Yes, I understand that. So you should be describing which ones have i/o
and what they are connected to. The PWM binding is probably a starting
point.
Rob
>
>
> - Paul
>
^ permalink raw reply [flat|nested] 65+ messages in thread
[parent not found: <50017BB1.8010702-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-14 14:01 ` Rob Herring
@ 2012-07-14 17:42 ` Paul Walmsley
-1 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-14 17:42 UTC (permalink / raw)
To: Rob Herring; +Cc: device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
Hi Rob,
thanks for your response.
On Sat, 14 Jul 2012, Rob Herring wrote:
> On 07/14/2012 01:56 AM, Paul Walmsley wrote:
> > On Fri, 13 Jul 2012, Rob Herring wrote:
> >
> >> I'm not sure this is really a good use of aliases. UARTs use aliases
> >> because it is important that the UART number to tty number is known and
> >> fixed. IIUC, as an example you are picking timer1 because it has
> >> properties X, Y and Z. If so, then you should describe those h/w
> >> properties within the timer nodes so you can pick which timer to use
> >> based on it's h/w properties.
> >
> > Some GPTIMER blocks have input and output signals that can be routed to
> > external package balls. So it's possible that some application may need
> > to request a specific timer ID, since that timer would be connected to a
> > specific off-chip device.
>
> Yes, I understand that. So you
(just to clarify, these are Jon's patches)
> should be describing which ones have i/o and what they are connected to.
Right, agreed.
> The PWM binding is probably a starting point.
My point, perhaps unclear, was about the aliases. Do you have a different
approach in mind that applications should use, other than requesting a
specific timer by ID?
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-14 17:42 ` Paul Walmsley
0 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-14 17:42 UTC (permalink / raw)
To: linux-arm-kernel
Hi Rob,
thanks for your response.
On Sat, 14 Jul 2012, Rob Herring wrote:
> On 07/14/2012 01:56 AM, Paul Walmsley wrote:
> > On Fri, 13 Jul 2012, Rob Herring wrote:
> >
> >> I'm not sure this is really a good use of aliases. UARTs use aliases
> >> because it is important that the UART number to tty number is known and
> >> fixed. IIUC, as an example you are picking timer1 because it has
> >> properties X, Y and Z. If so, then you should describe those h/w
> >> properties within the timer nodes so you can pick which timer to use
> >> based on it's h/w properties.
> >
> > Some GPTIMER blocks have input and output signals that can be routed to
> > external package balls. So it's possible that some application may need
> > to request a specific timer ID, since that timer would be connected to a
> > specific off-chip device.
>
> Yes, I understand that. So you
(just to clarify, these are Jon's patches)
> should be describing which ones have i/o and what they are connected to.
Right, agreed.
> The PWM binding is probably a starting point.
My point, perhaps unclear, was about the aliases. Do you have a different
approach in mind that applications should use, other than requesting a
specific timer by ID?
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-14 17:42 ` Paul Walmsley
@ 2012-07-16 17:48 ` Paul Walmsley
-1 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-16 17:48 UTC (permalink / raw)
To: Rob Herring
Cc: Jon Hunter, Tarun Kanti DebBarma, Tony Lindgren, Grant Likely,
Benoit Cousson, linux-omap, linux-arm, device-tree
Hi Rob,
On Sat, 14 Jul 2012, Paul Walmsley wrote:
> My point, perhaps unclear, was about the aliases. Do you have a different
> approach in mind that applications should use, other than requesting a
> specific timer by ID?
Please disregard this question, I think I'm misunderstanding something
from a previous mail...
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-16 17:48 ` Paul Walmsley
0 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-16 17:48 UTC (permalink / raw)
To: linux-arm-kernel
Hi Rob,
On Sat, 14 Jul 2012, Paul Walmsley wrote:
> My point, perhaps unclear, was about the aliases. Do you have a different
> approach in mind that applications should use, other than requesting a
> specific timer by ID?
Please disregard this question, I think I'm misunderstanding something
from a previous mail...
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-14 2:15 ` Rob Herring
@ 2012-07-16 15:56 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-16 15:56 UTC (permalink / raw)
To: Rob Herring
Cc: Tarun Kanti DebBarma, Tony Lindgren, Grant Likely, Paul Walmsley,
Benoit Cousson, linux-omap, linux-arm, device-tree
Hi Rob,
On 07/13/2012 09:15 PM, Rob Herring wrote:
> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>> Add the 12 GP timers nodes present in OMAP3.
>> Add the 11 GP timers nodes present in OMAP4.
>>
>> Add documentation for timer properties specific to OMAP.
>>
>> For each timer an alias is being added. The purpose for doing this is because
>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>> instances. For example, a timer can be requested by its ID. By adding an alias
>> for each timer we can then use the function of_alias_get_id() to extract the
>> ID for each timer from the alias name. The same method is used for the TTY
>> serial devices. If it is preferred that such an alias is not added and there
>> is a better way to pass an ID from device-tree let me know.
>
> I'm not sure this is really a good use of aliases. UARTs use aliases
> because it is important that the UART number to tty number is known and
> fixed. IIUC, as an example you are picking timer1 because it has
> properties X, Y and Z. If so, then you should describe those h/w
> properties within the timer nodes so you can pick which timer to use
> based on it's h/w properties.
Thanks for the feedback. What you suggest could definitely work for most
timers. The only item that I would need to resolve here is the handling
of system timers (ie. those used for clockevents and clocksource). These
system timers (for OMAP) are reserved during early boot based upon the
timer ID today and so this is before the actual main timer driver has
been probed and all the attributes of the timers has been read for
device-tree.
One thought would be to move the reservation of the system timers out of
the kernel and into device-tree itself. Then we query device tree on
start-up to see which we should use. I am wondering if this could be a
better use of alias? For example, say I want to use timer1 as my
clockevent timer and so I could have an alias of ...
alias {
clockevent_timer = &timer1;
}
However, I am not sure if this is even correct, because there does not
appear to be an API to search the aliases by name and return the
phandle, just of_alias_get_id(). Alternatively, I could add another
property called "ti,timer-clockevent" that is populated for the timer
used as the clockevent timer.
Tony, Tarun,
How would you feel on replacing omap_dmtimer_request_specific(int id)
with say omap_dm_timer_request_by_cap(int cap)?
I was thinking of changing the name so that it is clear that the API has
changed. The "int cap" passed to the above function would be an OR of
the appropriate the capabilities flags we have in dmtimer.h ...
/* timer capabilities used in hwmod database */
#define OMAP_TIMER_SECURE 0x80000000
#define OMAP_TIMER_ALWON 0x40000000
#define OMAP_TIMER_HAS_PWM 0x20000000
...
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-16 15:56 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-16 15:56 UTC (permalink / raw)
To: linux-arm-kernel
Hi Rob,
On 07/13/2012 09:15 PM, Rob Herring wrote:
> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>> Add the 12 GP timers nodes present in OMAP3.
>> Add the 11 GP timers nodes present in OMAP4.
>>
>> Add documentation for timer properties specific to OMAP.
>>
>> For each timer an alias is being added. The purpose for doing this is because
>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>> instances. For example, a timer can be requested by its ID. By adding an alias
>> for each timer we can then use the function of_alias_get_id() to extract the
>> ID for each timer from the alias name. The same method is used for the TTY
>> serial devices. If it is preferred that such an alias is not added and there
>> is a better way to pass an ID from device-tree let me know.
>
> I'm not sure this is really a good use of aliases. UARTs use aliases
> because it is important that the UART number to tty number is known and
> fixed. IIUC, as an example you are picking timer1 because it has
> properties X, Y and Z. If so, then you should describe those h/w
> properties within the timer nodes so you can pick which timer to use
> based on it's h/w properties.
Thanks for the feedback. What you suggest could definitely work for most
timers. The only item that I would need to resolve here is the handling
of system timers (ie. those used for clockevents and clocksource). These
system timers (for OMAP) are reserved during early boot based upon the
timer ID today and so this is before the actual main timer driver has
been probed and all the attributes of the timers has been read for
device-tree.
One thought would be to move the reservation of the system timers out of
the kernel and into device-tree itself. Then we query device tree on
start-up to see which we should use. I am wondering if this could be a
better use of alias? For example, say I want to use timer1 as my
clockevent timer and so I could have an alias of ...
alias {
clockevent_timer = &timer1;
}
However, I am not sure if this is even correct, because there does not
appear to be an API to search the aliases by name and return the
phandle, just of_alias_get_id(). Alternatively, I could add another
property called "ti,timer-clockevent" that is populated for the timer
used as the clockevent timer.
Tony, Tarun,
How would you feel on replacing omap_dmtimer_request_specific(int id)
with say omap_dm_timer_request_by_cap(int cap)?
I was thinking of changing the name so that it is clear that the API has
changed. The "int cap" passed to the above function would be an OR of
the appropriate the capabilities flags we have in dmtimer.h ...
/* timer capabilities used in hwmod database */
#define OMAP_TIMER_SECURE 0x80000000
#define OMAP_TIMER_ALWON 0x40000000
#define OMAP_TIMER_HAS_PWM 0x20000000
...
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-16 15:56 ` Jon Hunter
@ 2012-07-18 7:19 ` Tony Lindgren
-1 siblings, 0 replies; 65+ messages in thread
From: Tony Lindgren @ 2012-07-18 7:19 UTC (permalink / raw)
To: Jon Hunter
Cc: Rob Herring, Tarun Kanti DebBarma, Grant Likely, Paul Walmsley,
Benoit Cousson, linux-omap, linux-arm, device-tree
* Jon Hunter <jon-hunter@ti.com> [120716 09:01]:
> On 07/13/2012 09:15 PM, Rob Herring wrote:
>
> Tony, Tarun,
>
> How would you feel on replacing omap_dmtimer_request_specific(int id)
> with say omap_dm_timer_request_by_cap(int cap)?
>
> I was thinking of changing the name so that it is clear that the API has
> changed. The "int cap" passed to the above function would be an OR of
> the appropriate the capabilities flags we have in dmtimer.h ...
>
> /* timer capabilities used in hwmod database */
> #define OMAP_TIMER_SECURE 0x80000000
> #define OMAP_TIMER_ALWON 0x40000000
> #define OMAP_TIMER_HAS_PWM 0x20000000
> ...
That may break coprocessors where the firmware may expect a hardcoded
specific timer.. So at least that should be checked before the change.
If the specific timer is still needed for some firmware, it's best to
add a separate function for the capabilities.
Also, I believe it's up to the firmware running in secure mode to
select the secure timers. So unless there's some way to query which
timers are claimed by the secure mode, that too needs to be passed
via DT.
Regards,
Tony
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-18 7:19 ` Tony Lindgren
0 siblings, 0 replies; 65+ messages in thread
From: Tony Lindgren @ 2012-07-18 7:19 UTC (permalink / raw)
To: linux-arm-kernel
* Jon Hunter <jon-hunter@ti.com> [120716 09:01]:
> On 07/13/2012 09:15 PM, Rob Herring wrote:
>
> Tony, Tarun,
>
> How would you feel on replacing omap_dmtimer_request_specific(int id)
> with say omap_dm_timer_request_by_cap(int cap)?
>
> I was thinking of changing the name so that it is clear that the API has
> changed. The "int cap" passed to the above function would be an OR of
> the appropriate the capabilities flags we have in dmtimer.h ...
>
> /* timer capabilities used in hwmod database */
> #define OMAP_TIMER_SECURE 0x80000000
> #define OMAP_TIMER_ALWON 0x40000000
> #define OMAP_TIMER_HAS_PWM 0x20000000
> ...
That may break coprocessors where the firmware may expect a hardcoded
specific timer.. So at least that should be checked before the change.
If the specific timer is still needed for some firmware, it's best to
add a separate function for the capabilities.
Also, I believe it's up to the firmware running in secure mode to
select the secure timers. So unless there's some way to query which
timers are claimed by the secure mode, that too needs to be passed
via DT.
Regards,
Tony
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-18 7:19 ` Tony Lindgren
@ 2012-07-18 15:11 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-18 15:11 UTC (permalink / raw)
To: Tony Lindgren
Cc: Rob Herring, Tarun Kanti DebBarma, Grant Likely, Paul Walmsley,
Benoit Cousson, linux-omap, linux-arm, device-tree
Hi Tony,
On 07/18/2012 02:19 AM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@ti.com> [120716 09:01]:
>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>
>> Tony, Tarun,
>>
>> How would you feel on replacing omap_dmtimer_request_specific(int id)
>> with say omap_dm_timer_request_by_cap(int cap)?
>>
>> I was thinking of changing the name so that it is clear that the API has
>> changed. The "int cap" passed to the above function would be an OR of
>> the appropriate the capabilities flags we have in dmtimer.h ...
>>
>> /* timer capabilities used in hwmod database */
>> #define OMAP_TIMER_SECURE 0x80000000
>> #define OMAP_TIMER_ALWON 0x40000000
>> #define OMAP_TIMER_HAS_PWM 0x20000000
>> ...
>
> That may break coprocessors where the firmware may expect a hardcoded
> specific timer.. So at least that should be checked before the change.
> If the specific timer is still needed for some firmware, it's best to
> add a separate function for the capabilities.
I have seen that timers are used by the GPU and Ducati. Maybe I can
check with the authors to see if we can get them to request by
capability instead. If we can't then I need to figure out a way to
resolve the timer ID when using DT. Per Rob's comments using alias is
not the intended use. An alternative would be to extract the ID from the
hwmod name, but was not sure if that would be appropriate either :-(
> Also, I believe it's up to the firmware running in secure mode to
> select the secure timers. So unless there's some way to query which
> timers are claimed by the secure mode, that too needs to be passed
> via DT.
Yes, that is handled by patch 2/4. If we are on a secure device, then
will not register any timers marked with the "ti,timer-secure" property.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-18 15:11 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-18 15:11 UTC (permalink / raw)
To: linux-arm-kernel
Hi Tony,
On 07/18/2012 02:19 AM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@ti.com> [120716 09:01]:
>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>
>> Tony, Tarun,
>>
>> How would you feel on replacing omap_dmtimer_request_specific(int id)
>> with say omap_dm_timer_request_by_cap(int cap)?
>>
>> I was thinking of changing the name so that it is clear that the API has
>> changed. The "int cap" passed to the above function would be an OR of
>> the appropriate the capabilities flags we have in dmtimer.h ...
>>
>> /* timer capabilities used in hwmod database */
>> #define OMAP_TIMER_SECURE 0x80000000
>> #define OMAP_TIMER_ALWON 0x40000000
>> #define OMAP_TIMER_HAS_PWM 0x20000000
>> ...
>
> That may break coprocessors where the firmware may expect a hardcoded
> specific timer.. So at least that should be checked before the change.
> If the specific timer is still needed for some firmware, it's best to
> add a separate function for the capabilities.
I have seen that timers are used by the GPU and Ducati. Maybe I can
check with the authors to see if we can get them to request by
capability instead. If we can't then I need to figure out a way to
resolve the timer ID when using DT. Per Rob's comments using alias is
not the intended use. An alternative would be to extract the ID from the
hwmod name, but was not sure if that would be appropriate either :-(
> Also, I believe it's up to the firmware running in secure mode to
> select the secure timers. So unless there's some way to query which
> timers are claimed by the secure mode, that too needs to be passed
> via DT.
Yes, that is handled by patch 2/4. If we are on a secure device, then
will not register any timers marked with the "ti,timer-secure" property.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-16 15:56 ` Jon Hunter
@ 2012-07-23 15:24 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-23 15:24 UTC (permalink / raw)
To: Rob Herring; +Cc: device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
Hi Rob,
On 07/16/2012 10:56 AM, Jon Hunter wrote:
> Hi Rob,
>
> On 07/13/2012 09:15 PM, Rob Herring wrote:
>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>> Add the 12 GP timers nodes present in OMAP3.
>>> Add the 11 GP timers nodes present in OMAP4.
>>>
>>> Add documentation for timer properties specific to OMAP.
>>>
>>> For each timer an alias is being added. The purpose for doing this is because
>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>> for each timer we can then use the function of_alias_get_id() to extract the
>>> ID for each timer from the alias name. The same method is used for the TTY
>>> serial devices. If it is preferred that such an alias is not added and there
>>> is a better way to pass an ID from device-tree let me know.
>>
>> I'm not sure this is really a good use of aliases. UARTs use aliases
>> because it is important that the UART number to tty number is known and
>> fixed. IIUC, as an example you are picking timer1 because it has
>> properties X, Y and Z. If so, then you should describe those h/w
>> properties within the timer nodes so you can pick which timer to use
>> based on it's h/w properties.
>
> Thanks for the feedback. What you suggest could definitely work for most
> timers. The only item that I would need to resolve here is the handling
> of system timers (ie. those used for clockevents and clocksource). These
> system timers (for OMAP) are reserved during early boot based upon the
> timer ID today and so this is before the actual main timer driver has
> been probed and all the attributes of the timers has been read for
> device-tree.
>
> One thought would be to move the reservation of the system timers out of
> the kernel and into device-tree itself. Then we query device tree on
> start-up to see which we should use. I am wondering if this could be a
> better use of alias? For example, say I want to use timer1 as my
> clockevent timer and so I could have an alias of ...
>
> alias {
> clockevent_timer = &timer1;
> }
>
> However, I am not sure if this is even correct, because there does not
> appear to be an API to search the aliases by name and return the
> phandle, just of_alias_get_id(). Alternatively, I could add another
> property called "ti,timer-clockevent" that is populated for the timer
> used as the clockevent timer.
Do you have any inputs on the above? Does it make sense to reserve timer
resources for kernel system timers in device-tree?
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-07-23 15:24 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-23 15:24 UTC (permalink / raw)
To: linux-arm-kernel
Hi Rob,
On 07/16/2012 10:56 AM, Jon Hunter wrote:
> Hi Rob,
>
> On 07/13/2012 09:15 PM, Rob Herring wrote:
>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>> Add the 12 GP timers nodes present in OMAP3.
>>> Add the 11 GP timers nodes present in OMAP4.
>>>
>>> Add documentation for timer properties specific to OMAP.
>>>
>>> For each timer an alias is being added. The purpose for doing this is because
>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>> for each timer we can then use the function of_alias_get_id() to extract the
>>> ID for each timer from the alias name. The same method is used for the TTY
>>> serial devices. If it is preferred that such an alias is not added and there
>>> is a better way to pass an ID from device-tree let me know.
>>
>> I'm not sure this is really a good use of aliases. UARTs use aliases
>> because it is important that the UART number to tty number is known and
>> fixed. IIUC, as an example you are picking timer1 because it has
>> properties X, Y and Z. If so, then you should describe those h/w
>> properties within the timer nodes so you can pick which timer to use
>> based on it's h/w properties.
>
> Thanks for the feedback. What you suggest could definitely work for most
> timers. The only item that I would need to resolve here is the handling
> of system timers (ie. those used for clockevents and clocksource). These
> system timers (for OMAP) are reserved during early boot based upon the
> timer ID today and so this is before the actual main timer driver has
> been probed and all the attributes of the timers has been read for
> device-tree.
>
> One thought would be to move the reservation of the system timers out of
> the kernel and into device-tree itself. Then we query device tree on
> start-up to see which we should use. I am wondering if this could be a
> better use of alias? For example, say I want to use timer1 as my
> clockevent timer and so I could have an alias of ...
>
> alias {
> clockevent_timer = &timer1;
> }
>
> However, I am not sure if this is even correct, because there does not
> appear to be an API to search the aliases by name and return the
> phandle, just of_alias_get_id(). Alternatively, I could add another
> property called "ti,timer-clockevent" that is populated for the timer
> used as the clockevent timer.
Do you have any inputs on the above? Does it make sense to reserve timer
resources for kernel system timers in device-tree?
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-23 15:24 ` Jon Hunter
@ 2012-08-15 9:11 ` Vaibhav Hiremath
-1 siblings, 0 replies; 65+ messages in thread
From: Vaibhav Hiremath @ 2012-08-15 9:11 UTC (permalink / raw)
To: Jon Hunter
Cc: Rob Herring, device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
On 7/23/2012 8:54 PM, Jon Hunter wrote:
> Hi Rob,
>
> On 07/16/2012 10:56 AM, Jon Hunter wrote:
>> Hi Rob,
>>
>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>>> Add the 12 GP timers nodes present in OMAP3.
>>>> Add the 11 GP timers nodes present in OMAP4.
>>>>
>>>> Add documentation for timer properties specific to OMAP.
>>>>
>>>> For each timer an alias is being added. The purpose for doing this is because
>>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>>> for each timer we can then use the function of_alias_get_id() to extract the
>>>> ID for each timer from the alias name. The same method is used for the TTY
>>>> serial devices. If it is preferred that such an alias is not added and there
>>>> is a better way to pass an ID from device-tree let me know.
>>>
>>> I'm not sure this is really a good use of aliases. UARTs use aliases
>>> because it is important that the UART number to tty number is known and
>>> fixed. IIUC, as an example you are picking timer1 because it has
>>> properties X, Y and Z. If so, then you should describe those h/w
>>> properties within the timer nodes so you can pick which timer to use
>>> based on it's h/w properties.
>>
>> Thanks for the feedback. What you suggest could definitely work for most
>> timers. The only item that I would need to resolve here is the handling
>> of system timers (ie. those used for clockevents and clocksource). These
>> system timers (for OMAP) are reserved during early boot based upon the
>> timer ID today and so this is before the actual main timer driver has
>> been probed and all the attributes of the timers has been read for
>> device-tree.
>>
>> One thought would be to move the reservation of the system timers out of
>> the kernel and into device-tree itself. Then we query device tree on
>> start-up to see which we should use. I am wondering if this could be a
>> better use of alias? For example, say I want to use timer1 as my
>> clockevent timer and so I could have an alias of ...
>>
>> alias {
>> clockevent_timer = &timer1;
>> }
>>
>> However, I am not sure if this is even correct, because there does not
>> appear to be an API to search the aliases by name and return the
>> phandle, just of_alias_get_id(). Alternatively, I could add another
>> property called "ti,timer-clockevent" that is populated for the timer
>> used as the clockevent timer.
>
> Do you have any inputs on the above? Does it make sense to reserve timer
> resources for kernel system timers in device-tree?
>
Hey Jon,
Did we get conclude on this? I haven't got anything further on this
thread, this may block baseport support for the new devices in omap2
family, like AM33xx and OMAP5.
Thanks,
Vaibhav
> Cheers
> Jon
> _______________________________________________
> devicetree-discuss mailing list
> devicetree-discuss@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/devicetree-discuss
>
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-08-15 9:11 ` Vaibhav Hiremath
0 siblings, 0 replies; 65+ messages in thread
From: Vaibhav Hiremath @ 2012-08-15 9:11 UTC (permalink / raw)
To: linux-arm-kernel
On 7/23/2012 8:54 PM, Jon Hunter wrote:
> Hi Rob,
>
> On 07/16/2012 10:56 AM, Jon Hunter wrote:
>> Hi Rob,
>>
>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>>> Add the 12 GP timers nodes present in OMAP3.
>>>> Add the 11 GP timers nodes present in OMAP4.
>>>>
>>>> Add documentation for timer properties specific to OMAP.
>>>>
>>>> For each timer an alias is being added. The purpose for doing this is because
>>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>>> for each timer we can then use the function of_alias_get_id() to extract the
>>>> ID for each timer from the alias name. The same method is used for the TTY
>>>> serial devices. If it is preferred that such an alias is not added and there
>>>> is a better way to pass an ID from device-tree let me know.
>>>
>>> I'm not sure this is really a good use of aliases. UARTs use aliases
>>> because it is important that the UART number to tty number is known and
>>> fixed. IIUC, as an example you are picking timer1 because it has
>>> properties X, Y and Z. If so, then you should describe those h/w
>>> properties within the timer nodes so you can pick which timer to use
>>> based on it's h/w properties.
>>
>> Thanks for the feedback. What you suggest could definitely work for most
>> timers. The only item that I would need to resolve here is the handling
>> of system timers (ie. those used for clockevents and clocksource). These
>> system timers (for OMAP) are reserved during early boot based upon the
>> timer ID today and so this is before the actual main timer driver has
>> been probed and all the attributes of the timers has been read for
>> device-tree.
>>
>> One thought would be to move the reservation of the system timers out of
>> the kernel and into device-tree itself. Then we query device tree on
>> start-up to see which we should use. I am wondering if this could be a
>> better use of alias? For example, say I want to use timer1 as my
>> clockevent timer and so I could have an alias of ...
>>
>> alias {
>> clockevent_timer = &timer1;
>> }
>>
>> However, I am not sure if this is even correct, because there does not
>> appear to be an API to search the aliases by name and return the
>> phandle, just of_alias_get_id(). Alternatively, I could add another
>> property called "ti,timer-clockevent" that is populated for the timer
>> used as the clockevent timer.
>
> Do you have any inputs on the above? Does it make sense to reserve timer
> resources for kernel system timers in device-tree?
>
Hey Jon,
Did we get conclude on this? I haven't got anything further on this
thread, this may block baseport support for the new devices in omap2
family, like AM33xx and OMAP5.
Thanks,
Vaibhav
> Cheers
> Jon
> _______________________________________________
> devicetree-discuss mailing list
> devicetree-discuss at lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/devicetree-discuss
>
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-08-15 9:11 ` Vaibhav Hiremath
@ 2012-08-16 15:04 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-08-16 15:04 UTC (permalink / raw)
To: Vaibhav Hiremath
Cc: Rob Herring, device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
Hi Vaibhav,
On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
>
>
> On 7/23/2012 8:54 PM, Jon Hunter wrote:
>> Hi Rob,
>>
>> On 07/16/2012 10:56 AM, Jon Hunter wrote:
>>> Hi Rob,
>>>
>>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>>>> Add the 12 GP timers nodes present in OMAP3.
>>>>> Add the 11 GP timers nodes present in OMAP4.
>>>>>
>>>>> Add documentation for timer properties specific to OMAP.
>>>>>
>>>>> For each timer an alias is being added. The purpose for doing this is because
>>>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>>>> for each timer we can then use the function of_alias_get_id() to extract the
>>>>> ID for each timer from the alias name. The same method is used for the TTY
>>>>> serial devices. If it is preferred that such an alias is not added and there
>>>>> is a better way to pass an ID from device-tree let me know.
>>>>
>>>> I'm not sure this is really a good use of aliases. UARTs use aliases
>>>> because it is important that the UART number to tty number is known and
>>>> fixed. IIUC, as an example you are picking timer1 because it has
>>>> properties X, Y and Z. If so, then you should describe those h/w
>>>> properties within the timer nodes so you can pick which timer to use
>>>> based on it's h/w properties.
>>>
>>> Thanks for the feedback. What you suggest could definitely work for most
>>> timers. The only item that I would need to resolve here is the handling
>>> of system timers (ie. those used for clockevents and clocksource). These
>>> system timers (for OMAP) are reserved during early boot based upon the
>>> timer ID today and so this is before the actual main timer driver has
>>> been probed and all the attributes of the timers has been read for
>>> device-tree.
>>>
>>> One thought would be to move the reservation of the system timers out of
>>> the kernel and into device-tree itself. Then we query device tree on
>>> start-up to see which we should use. I am wondering if this could be a
>>> better use of alias? For example, say I want to use timer1 as my
>>> clockevent timer and so I could have an alias of ...
>>>
>>> alias {
>>> clockevent_timer = &timer1;
>>> }
>>>
>>> However, I am not sure if this is even correct, because there does not
>>> appear to be an API to search the aliases by name and return the
>>> phandle, just of_alias_get_id(). Alternatively, I could add another
>>> property called "ti,timer-clockevent" that is populated for the timer
>>> used as the clockevent timer.
>>
>> Do you have any inputs on the above? Does it make sense to reserve timer
>> resources for kernel system timers in device-tree?
>>
>
> Hey Jon,
>
> Did we get conclude on this? I haven't got anything further on this
> thread, this may block baseport support for the new devices in omap2
> family, like AM33xx and OMAP5.
Sorry I have been out of the office. However, no update on this so far.
I need to check with Tony if he has any preference for handling this. I
will follow-up with him and keep you posted.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-08-16 15:04 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-08-16 15:04 UTC (permalink / raw)
To: linux-arm-kernel
Hi Vaibhav,
On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
>
>
> On 7/23/2012 8:54 PM, Jon Hunter wrote:
>> Hi Rob,
>>
>> On 07/16/2012 10:56 AM, Jon Hunter wrote:
>>> Hi Rob,
>>>
>>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>>>> Add the 12 GP timers nodes present in OMAP3.
>>>>> Add the 11 GP timers nodes present in OMAP4.
>>>>>
>>>>> Add documentation for timer properties specific to OMAP.
>>>>>
>>>>> For each timer an alias is being added. The purpose for doing this is because
>>>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>>>> for each timer we can then use the function of_alias_get_id() to extract the
>>>>> ID for each timer from the alias name. The same method is used for the TTY
>>>>> serial devices. If it is preferred that such an alias is not added and there
>>>>> is a better way to pass an ID from device-tree let me know.
>>>>
>>>> I'm not sure this is really a good use of aliases. UARTs use aliases
>>>> because it is important that the UART number to tty number is known and
>>>> fixed. IIUC, as an example you are picking timer1 because it has
>>>> properties X, Y and Z. If so, then you should describe those h/w
>>>> properties within the timer nodes so you can pick which timer to use
>>>> based on it's h/w properties.
>>>
>>> Thanks for the feedback. What you suggest could definitely work for most
>>> timers. The only item that I would need to resolve here is the handling
>>> of system timers (ie. those used for clockevents and clocksource). These
>>> system timers (for OMAP) are reserved during early boot based upon the
>>> timer ID today and so this is before the actual main timer driver has
>>> been probed and all the attributes of the timers has been read for
>>> device-tree.
>>>
>>> One thought would be to move the reservation of the system timers out of
>>> the kernel and into device-tree itself. Then we query device tree on
>>> start-up to see which we should use. I am wondering if this could be a
>>> better use of alias? For example, say I want to use timer1 as my
>>> clockevent timer and so I could have an alias of ...
>>>
>>> alias {
>>> clockevent_timer = &timer1;
>>> }
>>>
>>> However, I am not sure if this is even correct, because there does not
>>> appear to be an API to search the aliases by name and return the
>>> phandle, just of_alias_get_id(). Alternatively, I could add another
>>> property called "ti,timer-clockevent" that is populated for the timer
>>> used as the clockevent timer.
>>
>> Do you have any inputs on the above? Does it make sense to reserve timer
>> resources for kernel system timers in device-tree?
>>
>
> Hey Jon,
>
> Did we get conclude on this? I haven't got anything further on this
> thread, this may block baseport support for the new devices in omap2
> family, like AM33xx and OMAP5.
Sorry I have been out of the office. However, no update on this so far.
I need to check with Tony if he has any preference for handling this. I
will follow-up with him and keep you posted.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-08-16 15:04 ` Jon Hunter
@ 2012-08-30 20:14 ` Tony Lindgren
-1 siblings, 0 replies; 65+ messages in thread
From: Tony Lindgren @ 2012-08-30 20:14 UTC (permalink / raw)
To: Jon Hunter
Cc: Vaibhav Hiremath, Rob Herring, device-tree, linux-omap,
Tarun Kanti DebBarma, linux-arm
* Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
> >
> > Did we get conclude on this? I haven't got anything further on this
> > thread, this may block baseport support for the new devices in omap2
> > family, like AM33xx and OMAP5.
>
> Sorry I have been out of the office. However, no update on this so far.
> I need to check with Tony if he has any preference for handling this. I
> will follow-up with him and keep you posted.
Jon please repost these without the RFC in the subject line
assuming the pending comments have been addressed so people
can ack them.
Regards,
Tony
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-08-30 20:14 ` Tony Lindgren
0 siblings, 0 replies; 65+ messages in thread
From: Tony Lindgren @ 2012-08-30 20:14 UTC (permalink / raw)
To: linux-arm-kernel
* Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
> >
> > Did we get conclude on this? I haven't got anything further on this
> > thread, this may block baseport support for the new devices in omap2
> > family, like AM33xx and OMAP5.
>
> Sorry I have been out of the office. However, no update on this so far.
> I need to check with Tony if he has any preference for handling this. I
> will follow-up with him and keep you posted.
Jon please repost these without the RFC in the subject line
assuming the pending comments have been addressed so people
can ack them.
Regards,
Tony
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-08-30 20:14 ` Tony Lindgren
@ 2012-09-07 20:26 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-09-07 20:26 UTC (permalink / raw)
To: Tony Lindgren
Cc: Vaibhav Hiremath, Rob Herring, device-tree, linux-omap,
Tarun Kanti DebBarma, linux-arm
Hi Tony,
On 08/30/2012 03:14 PM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
>> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
>>>
>>> Did we get conclude on this? I haven't got anything further on this
>>> thread, this may block baseport support for the new devices in omap2
>>> family, like AM33xx and OMAP5.
>>
>> Sorry I have been out of the office. However, no update on this so far.
>> I need to check with Tony if he has any preference for handling this. I
>> will follow-up with him and keep you posted.
>
> Jon please repost these without the RFC in the subject line
> assuming the pending comments have been addressed so people
> can ack them.
I have been working on updating this series to request timer by their
capabilities and avoid using a device ID altogether. In the updated
series using device IDs to request a timer will still work as it does
today, but not when you boot with DT. I have something working now that
is booting fine on omap4 with and without DT [1]. However, I need to do
more thorough testing of the timers in general, probably next week.
Once I have completed my testing I would like to post for review.
However, since posting the original series I have been working on some
needed timer fixes/clean-up which I posted this week [2] for review.
Ideally I should rebase my DT timer work on my timer fixes series but
wanted to see what you thought first.
Cheers
Jon
[1] https://github.com/jonhunter/linux/tree/dev-dt-timer
[2] http://marc.info/?l=linux-omap&m=134687188921835&w=2
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-09-07 20:26 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-09-07 20:26 UTC (permalink / raw)
To: linux-arm-kernel
Hi Tony,
On 08/30/2012 03:14 PM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
>> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
>>>
>>> Did we get conclude on this? I haven't got anything further on this
>>> thread, this may block baseport support for the new devices in omap2
>>> family, like AM33xx and OMAP5.
>>
>> Sorry I have been out of the office. However, no update on this so far.
>> I need to check with Tony if he has any preference for handling this. I
>> will follow-up with him and keep you posted.
>
> Jon please repost these without the RFC in the subject line
> assuming the pending comments have been addressed so people
> can ack them.
I have been working on updating this series to request timer by their
capabilities and avoid using a device ID altogether. In the updated
series using device IDs to request a timer will still work as it does
today, but not when you boot with DT. I have something working now that
is booting fine on omap4 with and without DT [1]. However, I need to do
more thorough testing of the timers in general, probably next week.
Once I have completed my testing I would like to post for review.
However, since posting the original series I have been working on some
needed timer fixes/clean-up which I posted this week [2] for review.
Ideally I should rebase my DT timer work on my timer fixes series but
wanted to see what you thought first.
Cheers
Jon
[1] https://github.com/jonhunter/linux/tree/dev-dt-timer
[2] http://marc.info/?l=linux-omap&m=134687188921835&w=2
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-09-07 20:26 ` Jon Hunter
@ 2012-09-07 20:56 ` Tony Lindgren
-1 siblings, 0 replies; 65+ messages in thread
From: Tony Lindgren @ 2012-09-07 20:56 UTC (permalink / raw)
To: Jon Hunter
Cc: Vaibhav Hiremath, Rob Herring, device-tree, linux-omap,
Tarun Kanti DebBarma, linux-arm
* Jon Hunter <jon-hunter@ti.com> [120907 13:27]:
> Hi Tony,
>
> On 08/30/2012 03:14 PM, Tony Lindgren wrote:
> > * Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
> >> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
> >>>
> >>> Did we get conclude on this? I haven't got anything further on this
> >>> thread, this may block baseport support for the new devices in omap2
> >>> family, like AM33xx and OMAP5.
> >>
> >> Sorry I have been out of the office. However, no update on this so far.
> >> I need to check with Tony if he has any preference for handling this. I
> >> will follow-up with him and keep you posted.
> >
> > Jon please repost these without the RFC in the subject line
> > assuming the pending comments have been addressed so people
> > can ack them.
>
> I have been working on updating this series to request timer by their
> capabilities and avoid using a device ID altogether. In the updated
> series using device IDs to request a timer will still work as it does
> today, but not when you boot with DT. I have something working now that
> is booting fine on omap4 with and without DT [1]. However, I need to do
> more thorough testing of the timers in general, probably next week.
>
> Once I have completed my testing I would like to post for review.
> However, since posting the original series I have been working on some
> needed timer fixes/clean-up which I posted this week [2] for review.
> Ideally I should rebase my DT timer work on my timer fixes series but
> wanted to see what you thought first.
Yeah those all look good to me. Want to do a git branch against
v3.6-rc4 for those once the comments are dealt with so I can pull
it in for testing to start with?
Regards,
Tony
> Cheers
> Jon
>
> [1] https://github.com/jonhunter/linux/tree/dev-dt-timer
> [2] http://marc.info/?l=linux-omap&m=134687188921835&w=2
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-09-07 20:56 ` Tony Lindgren
0 siblings, 0 replies; 65+ messages in thread
From: Tony Lindgren @ 2012-09-07 20:56 UTC (permalink / raw)
To: linux-arm-kernel
* Jon Hunter <jon-hunter@ti.com> [120907 13:27]:
> Hi Tony,
>
> On 08/30/2012 03:14 PM, Tony Lindgren wrote:
> > * Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
> >> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
> >>>
> >>> Did we get conclude on this? I haven't got anything further on this
> >>> thread, this may block baseport support for the new devices in omap2
> >>> family, like AM33xx and OMAP5.
> >>
> >> Sorry I have been out of the office. However, no update on this so far.
> >> I need to check with Tony if he has any preference for handling this. I
> >> will follow-up with him and keep you posted.
> >
> > Jon please repost these without the RFC in the subject line
> > assuming the pending comments have been addressed so people
> > can ack them.
>
> I have been working on updating this series to request timer by their
> capabilities and avoid using a device ID altogether. In the updated
> series using device IDs to request a timer will still work as it does
> today, but not when you boot with DT. I have something working now that
> is booting fine on omap4 with and without DT [1]. However, I need to do
> more thorough testing of the timers in general, probably next week.
>
> Once I have completed my testing I would like to post for review.
> However, since posting the original series I have been working on some
> needed timer fixes/clean-up which I posted this week [2] for review.
> Ideally I should rebase my DT timer work on my timer fixes series but
> wanted to see what you thought first.
Yeah those all look good to me. Want to do a git branch against
v3.6-rc4 for those once the comments are dealt with so I can pull
it in for testing to start with?
Regards,
Tony
> Cheers
> Jon
>
> [1] https://github.com/jonhunter/linux/tree/dev-dt-timer
> [2] http://marc.info/?l=linux-omap&m=134687188921835&w=2
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-09-07 20:56 ` Tony Lindgren
@ 2012-09-07 21:16 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-09-07 21:16 UTC (permalink / raw)
To: Tony Lindgren
Cc: Vaibhav Hiremath, Rob Herring, device-tree, linux-omap,
Tarun Kanti DebBarma, linux-arm
On 09/07/2012 03:56 PM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@ti.com> [120907 13:27]:
>> Hi Tony,
>>
>> On 08/30/2012 03:14 PM, Tony Lindgren wrote:
>>> * Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
>>>> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
>>>>>
>>>>> Did we get conclude on this? I haven't got anything further on this
>>>>> thread, this may block baseport support for the new devices in omap2
>>>>> family, like AM33xx and OMAP5.
>>>>
>>>> Sorry I have been out of the office. However, no update on this so far.
>>>> I need to check with Tony if he has any preference for handling this. I
>>>> will follow-up with him and keep you posted.
>>>
>>> Jon please repost these without the RFC in the subject line
>>> assuming the pending comments have been addressed so people
>>> can ack them.
>>
>> I have been working on updating this series to request timer by their
>> capabilities and avoid using a device ID altogether. In the updated
>> series using device IDs to request a timer will still work as it does
>> today, but not when you boot with DT. I have something working now that
>> is booting fine on omap4 with and without DT [1]. However, I need to do
>> more thorough testing of the timers in general, probably next week.
>>
>> Once I have completed my testing I would like to post for review.
>> However, since posting the original series I have been working on some
>> needed timer fixes/clean-up which I posted this week [2] for review.
>> Ideally I should rebase my DT timer work on my timer fixes series but
>> wanted to see what you thought first.
>
> Yeah those all look good to me. Want to do a git branch against
> v3.6-rc4 for those once the comments are dealt with so I can pull
> it in for testing to start with?
The fixes series should already be based on top of 3.6-rc4 but will
update based upon comments. The only outstanding comment on those were
the implementation of the __omap_dm_timer_populate_errata() function.
Not sure if you have any comments. Vaibhav and myself are not completely
happy with it. I proposed something else but no feedback on that yet.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-09-07 21:16 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-09-07 21:16 UTC (permalink / raw)
To: linux-arm-kernel
On 09/07/2012 03:56 PM, Tony Lindgren wrote:
> * Jon Hunter <jon-hunter@ti.com> [120907 13:27]:
>> Hi Tony,
>>
>> On 08/30/2012 03:14 PM, Tony Lindgren wrote:
>>> * Jon Hunter <jon-hunter@ti.com> [120816 08:05]:
>>>> On 08/15/2012 04:11 AM, Vaibhav Hiremath wrote:
>>>>>
>>>>> Did we get conclude on this? I haven't got anything further on this
>>>>> thread, this may block baseport support for the new devices in omap2
>>>>> family, like AM33xx and OMAP5.
>>>>
>>>> Sorry I have been out of the office. However, no update on this so far.
>>>> I need to check with Tony if he has any preference for handling this. I
>>>> will follow-up with him and keep you posted.
>>>
>>> Jon please repost these without the RFC in the subject line
>>> assuming the pending comments have been addressed so people
>>> can ack them.
>>
>> I have been working on updating this series to request timer by their
>> capabilities and avoid using a device ID altogether. In the updated
>> series using device IDs to request a timer will still work as it does
>> today, but not when you boot with DT. I have something working now that
>> is booting fine on omap4 with and without DT [1]. However, I need to do
>> more thorough testing of the timers in general, probably next week.
>>
>> Once I have completed my testing I would like to post for review.
>> However, since posting the original series I have been working on some
>> needed timer fixes/clean-up which I posted this week [2] for review.
>> Ideally I should rebase my DT timer work on my timer fixes series but
>> wanted to see what you thought first.
>
> Yeah those all look good to me. Want to do a git branch against
> v3.6-rc4 for those once the comments are dealt with so I can pull
> it in for testing to start with?
The fixes series should already be based on top of 3.6-rc4 but will
update based upon comments. The only outstanding comment on those were
the implementation of the __omap_dm_timer_populate_errata() function.
Not sure if you have any comments. Vaibhav and myself are not completely
happy with it. I proposed something else but no feedback on that yet.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-07-23 15:24 ` Jon Hunter
@ 2012-09-06 13:45 ` Rob Herring
-1 siblings, 0 replies; 65+ messages in thread
From: Rob Herring @ 2012-09-06 13:45 UTC (permalink / raw)
To: Jon Hunter; +Cc: device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
On 07/23/2012 10:24 AM, Jon Hunter wrote:
> Hi Rob,
>
> On 07/16/2012 10:56 AM, Jon Hunter wrote:
>> Hi Rob,
>>
>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>>> Add the 12 GP timers nodes present in OMAP3.
>>>> Add the 11 GP timers nodes present in OMAP4.
>>>>
>>>> Add documentation for timer properties specific to OMAP.
>>>>
>>>> For each timer an alias is being added. The purpose for doing this is because
>>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>>> for each timer we can then use the function of_alias_get_id() to extract the
>>>> ID for each timer from the alias name. The same method is used for the TTY
>>>> serial devices. If it is preferred that such an alias is not added and there
>>>> is a better way to pass an ID from device-tree let me know.
>>>
>>> I'm not sure this is really a good use of aliases. UARTs use aliases
>>> because it is important that the UART number to tty number is known and
>>> fixed. IIUC, as an example you are picking timer1 because it has
>>> properties X, Y and Z. If so, then you should describe those h/w
>>> properties within the timer nodes so you can pick which timer to use
>>> based on it's h/w properties.
>>
>> Thanks for the feedback. What you suggest could definitely work for most
>> timers. The only item that I would need to resolve here is the handling
>> of system timers (ie. those used for clockevents and clocksource). These
>> system timers (for OMAP) are reserved during early boot based upon the
>> timer ID today and so this is before the actual main timer driver has
>> been probed and all the attributes of the timers has been read for
>> device-tree.
>>
>> One thought would be to move the reservation of the system timers out of
>> the kernel and into device-tree itself. Then we query device tree on
>> start-up to see which we should use. I am wondering if this could be a
>> better use of alias? For example, say I want to use timer1 as my
>> clockevent timer and so I could have an alias of ...
>>
>> alias {
>> clockevent_timer = &timer1;
>> }
>>
>> However, I am not sure if this is even correct, because there does not
>> appear to be an API to search the aliases by name and return the
>> phandle, just of_alias_get_id(). Alternatively, I could add another
>> property called "ti,timer-clockevent" that is populated for the timer
>> used as the clockevent timer.
>
> Do you have any inputs on the above? Does it make sense to reserve timer
> resources for kernel system timers in device-tree?
This issue is not unique to omap. So if we do specify clockevent and
clocksource in dts, then it should be in a common way. I think using
"linux,clockevent" either as an alias name or property within the timer
node would work. I don't have a strong preference, but I tend to lean
toward an alias. Primarily this is because we are already using aliases
for similar purposes.
However, I still think this could be done by looking at properties.
There's not really any reason you can't check properties at timer init
stage. The FDT has already been un-flattened. What are the features or
lack of features you care about to determine which timer to use?
Rob
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-09-06 13:45 ` Rob Herring
0 siblings, 0 replies; 65+ messages in thread
From: Rob Herring @ 2012-09-06 13:45 UTC (permalink / raw)
To: linux-arm-kernel
On 07/23/2012 10:24 AM, Jon Hunter wrote:
> Hi Rob,
>
> On 07/16/2012 10:56 AM, Jon Hunter wrote:
>> Hi Rob,
>>
>> On 07/13/2012 09:15 PM, Rob Herring wrote:
>>> On 07/13/2012 05:26 PM, Jon Hunter wrote:
>>>> Add the 12 GP timers nodes present in OMAP3.
>>>> Add the 11 GP timers nodes present in OMAP4.
>>>>
>>>> Add documentation for timer properties specific to OMAP.
>>>>
>>>> For each timer an alias is being added. The purpose for doing this is because
>>>> the OMAP dmtimer driver uses an ID to distinguish between the different timer
>>>> instances. For example, a timer can be requested by its ID. By adding an alias
>>>> for each timer we can then use the function of_alias_get_id() to extract the
>>>> ID for each timer from the alias name. The same method is used for the TTY
>>>> serial devices. If it is preferred that such an alias is not added and there
>>>> is a better way to pass an ID from device-tree let me know.
>>>
>>> I'm not sure this is really a good use of aliases. UARTs use aliases
>>> because it is important that the UART number to tty number is known and
>>> fixed. IIUC, as an example you are picking timer1 because it has
>>> properties X, Y and Z. If so, then you should describe those h/w
>>> properties within the timer nodes so you can pick which timer to use
>>> based on it's h/w properties.
>>
>> Thanks for the feedback. What you suggest could definitely work for most
>> timers. The only item that I would need to resolve here is the handling
>> of system timers (ie. those used for clockevents and clocksource). These
>> system timers (for OMAP) are reserved during early boot based upon the
>> timer ID today and so this is before the actual main timer driver has
>> been probed and all the attributes of the timers has been read for
>> device-tree.
>>
>> One thought would be to move the reservation of the system timers out of
>> the kernel and into device-tree itself. Then we query device tree on
>> start-up to see which we should use. I am wondering if this could be a
>> better use of alias? For example, say I want to use timer1 as my
>> clockevent timer and so I could have an alias of ...
>>
>> alias {
>> clockevent_timer = &timer1;
>> }
>>
>> However, I am not sure if this is even correct, because there does not
>> appear to be an API to search the aliases by name and return the
>> phandle, just of_alias_get_id(). Alternatively, I could add another
>> property called "ti,timer-clockevent" that is populated for the timer
>> used as the clockevent timer.
>
> Do you have any inputs on the above? Does it make sense to reserve timer
> resources for kernel system timers in device-tree?
This issue is not unique to omap. So if we do specify clockevent and
clocksource in dts, then it should be in a common way. I think using
"linux,clockevent" either as an alias name or property within the timer
node would work. I don't have a strong preference, but I tend to lean
toward an alias. Primarily this is because we are already using aliases
for similar purposes.
However, I still think this could be done by looking at properties.
There's not really any reason you can't check properties at timer init
stage. The FDT has already been un-flattened. What are the features or
lack of features you care about to determine which timer to use?
Rob
^ permalink raw reply [flat|nested] 65+ messages in thread[parent not found: <5048A8F6.6080108-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]
* Re: [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
2012-09-06 13:45 ` Rob Herring
@ 2012-09-07 2:09 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-09-07 2:09 UTC (permalink / raw)
To: Rob Herring; +Cc: device-tree, linux-omap, Tarun Kanti DebBarma, linux-arm
On 09/06/2012 08:45 AM, Rob Herring wrote:
> On 07/23/2012 10:24 AM, Jon Hunter wrote:
[snip]
>> Do you have any inputs on the above? Does it make sense to reserve timer
>> resources for kernel system timers in device-tree?
>
> This issue is not unique to omap. So if we do specify clockevent and
> clocksource in dts, then it should be in a common way. I think using
> "linux,clockevent" either as an alias name or property within the timer
> node would work. I don't have a strong preference, but I tend to lean
> toward an alias. Primarily this is because we are already using aliases
> for similar purposes.
>
> However, I still think this could be done by looking at properties.
> There's not really any reason you can't check properties at timer init
> stage. The FDT has already been un-flattened. What are the features or
> lack of features you care about to determine which timer to use?
I agree. Currently, I am looking into implementing something that will
use timer properties to select the system timers for the kernel and not
require us to select them in the device-tree. Once I have something
working I will send out for review.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 1/4] arm/dts: OMAP: Add timer nodes
@ 2012-09-07 2:09 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-09-07 2:09 UTC (permalink / raw)
To: linux-arm-kernel
On 09/06/2012 08:45 AM, Rob Herring wrote:
> On 07/23/2012 10:24 AM, Jon Hunter wrote:
[snip]
>> Do you have any inputs on the above? Does it make sense to reserve timer
>> resources for kernel system timers in device-tree?
>
> This issue is not unique to omap. So if we do specify clockevent and
> clocksource in dts, then it should be in a common way. I think using
> "linux,clockevent" either as an alias name or property within the timer
> node would work. I don't have a strong preference, but I tend to lean
> toward an alias. Primarily this is because we are already using aliases
> for similar purposes.
>
> However, I still think this could be done by looking at properties.
> There's not really any reason you can't check properties at timer init
> stage. The FDT has already been un-flattened. What are the features or
> lack of features you care about to determine which timer to use?
I agree. Currently, I am looking into implementing something that will
use timer properties to select the system timers for the kernel and not
require us to select them in the device-tree. Once I have something
working I will send out for review.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
2012-07-13 22:26 ` Jon Hunter
@ 2012-07-13 22:26 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley
Cc: Benoit Cousson, linux-omap, linux-arm, device-tree, Jon Hunter
OMAP3 devices may or may not have security features enabled. Security enabled
devices are known as high-secure (HS) and devices without security are known as
general purpose (GP).
For OMAP3 devices there are 12 general purpose timers available. On secure
devices the 12th timer is reserved for secure usage and so cannot be used by
the kernel, where as for a GP device it is available. We can detect the OMAP
device type, secure or GP, at runtime via an on-chip register. Today, when not
using DT, we do not register the 12th timer as a linux device if the device is
secure.
When using device tree, device tree is going to register all the timer devices
it finds in the device tree blob. To prevent device tree from registering 12th
timer on a secure OMAP3 device we can add a status property to the timer
binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
device has a property "ti,timer-secure" to indicate that it will not be
available on a secure device and so for secure OMAP3 devices, we search for
timers with this property and then disable them. Using the prom_add_property()
function to dynamically add a property was a recommended approach suggested by
Rob Herring [1].
I have tested this on an OMAP3 GP device and faking it to pretend to be a
secure device to ensure that any timers marked with "ti,timer-secure" are not
registered on boot. I have also made sure that all timers are registered as
expected on a GP device by default.
[1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
arch/arm/mach-omap2/board-generic.c | 1 +
arch/arm/mach-omap2/common.h | 1 +
arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
3 files changed, 38 insertions(+)
diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
index 6f93a20..20124d7 100644
--- a/arch/arm/mach-omap2/board-generic.c
+++ b/arch/arm/mach-omap2/board-generic.c
@@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
static void __init omap_generic_init(void)
{
omap_sdrc_init(NULL, NULL);
+ omap_dmtimer_init();
of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
}
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
index 1f65b18..d6a4875 100644
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
struct omap_sdrc_params *sdrc_cs1);
struct omap2_hsmmc_info;
extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
+extern void omap_dmtimer_init(void);
#endif /* __ASSEMBLER__ */
#endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 13d20c8..e3b9931 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -36,6 +36,7 @@
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <asm/mach/time.h>
#include <plat/dmtimer.h>
@@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
}
arch_initcall(omap2_dm_timer_init);
+static struct property timer_disabled = {
+ .name = "status",
+ .length = sizeof("disabled"),
+ .value = "disabled",
+};
+
+static struct of_device_id omap3_timer_match[] __initdata = {
+ { .compatible = "ti,omap3-timer", },
+ { }
+};
+
+/**
+ * omap_dmtimer_init - initialisation function when device tree is used
+ *
+ * For secure OMAP3 devices, timers with device type "timer-secure" cannot
+ * be used by the kernel as they are reserved. Therefore, to prevent the
+ * kernel registering these devices remove them dynamically from the device
+ * tree on boot.
+ */
+void __init omap_dmtimer_init(void)
+{
+ struct device_node *np;
+
+ if (!cpu_is_omap34xx())
+ return;
+
+ /* If we are a secure device, remove any secure timer nodes */
+ if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
+ for_each_matching_node(np, omap3_timer_match) {
+ if (of_get_property(np, "ti,timer-secure", NULL))
+ prom_add_property(np, &timer_disabled);
+ }
+ }
+}
+
/**
* omap2_override_clocksource - clocksource override with user configuration
*
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
@ 2012-07-13 22:26 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: linux-arm-kernel
OMAP3 devices may or may not have security features enabled. Security enabled
devices are known as high-secure (HS) and devices without security are known as
general purpose (GP).
For OMAP3 devices there are 12 general purpose timers available. On secure
devices the 12th timer is reserved for secure usage and so cannot be used by
the kernel, where as for a GP device it is available. We can detect the OMAP
device type, secure or GP, at runtime via an on-chip register. Today, when not
using DT, we do not register the 12th timer as a linux device if the device is
secure.
When using device tree, device tree is going to register all the timer devices
it finds in the device tree blob. To prevent device tree from registering 12th
timer on a secure OMAP3 device we can add a status property to the timer
binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
device has a property "ti,timer-secure" to indicate that it will not be
available on a secure device and so for secure OMAP3 devices, we search for
timers with this property and then disable them. Using the prom_add_property()
function to dynamically add a property was a recommended approach suggested by
Rob Herring [1].
I have tested this on an OMAP3 GP device and faking it to pretend to be a
secure device to ensure that any timers marked with "ti,timer-secure" are not
registered on boot. I have also made sure that all timers are registered as
expected on a GP device by default.
[1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
arch/arm/mach-omap2/board-generic.c | 1 +
arch/arm/mach-omap2/common.h | 1 +
arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
3 files changed, 38 insertions(+)
diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
index 6f93a20..20124d7 100644
--- a/arch/arm/mach-omap2/board-generic.c
+++ b/arch/arm/mach-omap2/board-generic.c
@@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
static void __init omap_generic_init(void)
{
omap_sdrc_init(NULL, NULL);
+ omap_dmtimer_init();
of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
}
diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
index 1f65b18..d6a4875 100644
--- a/arch/arm/mach-omap2/common.h
+++ b/arch/arm/mach-omap2/common.h
@@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
struct omap_sdrc_params *sdrc_cs1);
struct omap2_hsmmc_info;
extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
+extern void omap_dmtimer_init(void);
#endif /* __ASSEMBLER__ */
#endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index 13d20c8..e3b9931 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -36,6 +36,7 @@
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <asm/mach/time.h>
#include <plat/dmtimer.h>
@@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
}
arch_initcall(omap2_dm_timer_init);
+static struct property timer_disabled = {
+ .name = "status",
+ .length = sizeof("disabled"),
+ .value = "disabled",
+};
+
+static struct of_device_id omap3_timer_match[] __initdata = {
+ { .compatible = "ti,omap3-timer", },
+ { }
+};
+
+/**
+ * omap_dmtimer_init - initialisation function when device tree is used
+ *
+ * For secure OMAP3 devices, timers with device type "timer-secure" cannot
+ * be used by the kernel as they are reserved. Therefore, to prevent the
+ * kernel registering these devices remove them dynamically from the device
+ * tree on boot.
+ */
+void __init omap_dmtimer_init(void)
+{
+ struct device_node *np;
+
+ if (!cpu_is_omap34xx())
+ return;
+
+ /* If we are a secure device, remove any secure timer nodes */
+ if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
+ for_each_matching_node(np, omap3_timer_match) {
+ if (of_get_property(np, "ti,timer-secure", NULL))
+ prom_add_property(np, &timer_disabled);
+ }
+ }
+}
+
/**
* omap2_override_clocksource - clocksource override with user configuration
*
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* Re: [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
2012-07-13 22:26 ` Jon Hunter
@ 2012-08-15 9:13 ` Vaibhav Hiremath
-1 siblings, 0 replies; 65+ messages in thread
From: Vaibhav Hiremath @ 2012-08-15 9:13 UTC (permalink / raw)
To: Jon Hunter
Cc: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley, device-tree, linux-omap, linux-arm
On 7/14/2012 3:56 AM, Jon Hunter wrote:
> OMAP3 devices may or may not have security features enabled. Security enabled
> devices are known as high-secure (HS) and devices without security are known as
> general purpose (GP).
>
> For OMAP3 devices there are 12 general purpose timers available. On secure
> devices the 12th timer is reserved for secure usage and so cannot be used by
> the kernel, where as for a GP device it is available. We can detect the OMAP
> device type, secure or GP, at runtime via an on-chip register. Today, when not
> using DT, we do not register the 12th timer as a linux device if the device is
> secure.
>
> When using device tree, device tree is going to register all the timer devices
> it finds in the device tree blob. To prevent device tree from registering 12th
> timer on a secure OMAP3 device we can add a status property to the timer
> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
> device has a property "ti,timer-secure" to indicate that it will not be
> available on a secure device and so for secure OMAP3 devices, we search for
> timers with this property and then disable them. Using the prom_add_property()
> function to dynamically add a property was a recommended approach suggested by
> Rob Herring [1].
>
> I have tested this on an OMAP3 GP device and faking it to pretend to be a
> secure device to ensure that any timers marked with "ti,timer-secure" are not
> registered on boot. I have also made sure that all timers are registered as
> expected on a GP device by default.
>
> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
>
> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> ---
> arch/arm/mach-omap2/board-generic.c | 1 +
> arch/arm/mach-omap2/common.h | 1 +
> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
> 3 files changed, 38 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> index 6f93a20..20124d7 100644
> --- a/arch/arm/mach-omap2/board-generic.c
> +++ b/arch/arm/mach-omap2/board-generic.c
> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
> static void __init omap_generic_init(void)
> {
> omap_sdrc_init(NULL, NULL);
> + omap_dmtimer_init();
>
> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
> }
> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
> index 1f65b18..d6a4875 100644
> --- a/arch/arm/mach-omap2/common.h
> +++ b/arch/arm/mach-omap2/common.h
> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
> struct omap_sdrc_params *sdrc_cs1);
> struct omap2_hsmmc_info;
> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
> +extern void omap_dmtimer_init(void);
>
> #endif /* __ASSEMBLER__ */
> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> index 13d20c8..e3b9931 100644
> --- a/arch/arm/mach-omap2/timer.c
> +++ b/arch/arm/mach-omap2/timer.c
> @@ -36,6 +36,7 @@
> #include <linux/clocksource.h>
> #include <linux/clockchips.h>
> #include <linux/slab.h>
> +#include <linux/of.h>
>
> #include <asm/mach/time.h>
> #include <plat/dmtimer.h>
> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
> }
> arch_initcall(omap2_dm_timer_init);
>
> +static struct property timer_disabled = {
> + .name = "status",
> + .length = sizeof("disabled"),
> + .value = "disabled",
> +};
> +
> +static struct of_device_id omap3_timer_match[] __initdata = {
> + { .compatible = "ti,omap3-timer", },
> + { }
> +};
> +
> +/**
> + * omap_dmtimer_init - initialisation function when device tree is used
> + *
> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
> + * be used by the kernel as they are reserved. Therefore, to prevent the
> + * kernel registering these devices remove them dynamically from the device
> + * tree on boot.
> + */
> +void __init omap_dmtimer_init(void)
> +{
> + struct device_node *np;
> +
> + if (!cpu_is_omap34xx())
> + return;
> +
Sorry for responding so late, but why only omap34xx check here?
Isn't this applicable to all omap & non-omap devices?
Thanks,
Vaibhav
> + /* If we are a secure device, remove any secure timer nodes */
> + if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
> + for_each_matching_node(np, omap3_timer_match) {
> + if (of_get_property(np, "ti,timer-secure", NULL))
> + prom_add_property(np, &timer_disabled);
> + }
> + }
> +}
> +
> /**
> * omap2_override_clocksource - clocksource override with user configuration
> *
>
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
@ 2012-08-15 9:13 ` Vaibhav Hiremath
0 siblings, 0 replies; 65+ messages in thread
From: Vaibhav Hiremath @ 2012-08-15 9:13 UTC (permalink / raw)
To: linux-arm-kernel
On 7/14/2012 3:56 AM, Jon Hunter wrote:
> OMAP3 devices may or may not have security features enabled. Security enabled
> devices are known as high-secure (HS) and devices without security are known as
> general purpose (GP).
>
> For OMAP3 devices there are 12 general purpose timers available. On secure
> devices the 12th timer is reserved for secure usage and so cannot be used by
> the kernel, where as for a GP device it is available. We can detect the OMAP
> device type, secure or GP, at runtime via an on-chip register. Today, when not
> using DT, we do not register the 12th timer as a linux device if the device is
> secure.
>
> When using device tree, device tree is going to register all the timer devices
> it finds in the device tree blob. To prevent device tree from registering 12th
> timer on a secure OMAP3 device we can add a status property to the timer
> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
> device has a property "ti,timer-secure" to indicate that it will not be
> available on a secure device and so for secure OMAP3 devices, we search for
> timers with this property and then disable them. Using the prom_add_property()
> function to dynamically add a property was a recommended approach suggested by
> Rob Herring [1].
>
> I have tested this on an OMAP3 GP device and faking it to pretend to be a
> secure device to ensure that any timers marked with "ti,timer-secure" are not
> registered on boot. I have also made sure that all timers are registered as
> expected on a GP device by default.
>
> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
>
> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> ---
> arch/arm/mach-omap2/board-generic.c | 1 +
> arch/arm/mach-omap2/common.h | 1 +
> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
> 3 files changed, 38 insertions(+)
>
> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> index 6f93a20..20124d7 100644
> --- a/arch/arm/mach-omap2/board-generic.c
> +++ b/arch/arm/mach-omap2/board-generic.c
> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
> static void __init omap_generic_init(void)
> {
> omap_sdrc_init(NULL, NULL);
> + omap_dmtimer_init();
>
> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
> }
> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
> index 1f65b18..d6a4875 100644
> --- a/arch/arm/mach-omap2/common.h
> +++ b/arch/arm/mach-omap2/common.h
> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
> struct omap_sdrc_params *sdrc_cs1);
> struct omap2_hsmmc_info;
> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
> +extern void omap_dmtimer_init(void);
>
> #endif /* __ASSEMBLER__ */
> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> index 13d20c8..e3b9931 100644
> --- a/arch/arm/mach-omap2/timer.c
> +++ b/arch/arm/mach-omap2/timer.c
> @@ -36,6 +36,7 @@
> #include <linux/clocksource.h>
> #include <linux/clockchips.h>
> #include <linux/slab.h>
> +#include <linux/of.h>
>
> #include <asm/mach/time.h>
> #include <plat/dmtimer.h>
> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
> }
> arch_initcall(omap2_dm_timer_init);
>
> +static struct property timer_disabled = {
> + .name = "status",
> + .length = sizeof("disabled"),
> + .value = "disabled",
> +};
> +
> +static struct of_device_id omap3_timer_match[] __initdata = {
> + { .compatible = "ti,omap3-timer", },
> + { }
> +};
> +
> +/**
> + * omap_dmtimer_init - initialisation function when device tree is used
> + *
> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
> + * be used by the kernel as they are reserved. Therefore, to prevent the
> + * kernel registering these devices remove them dynamically from the device
> + * tree on boot.
> + */
> +void __init omap_dmtimer_init(void)
> +{
> + struct device_node *np;
> +
> + if (!cpu_is_omap34xx())
> + return;
> +
Sorry for responding so late, but why only omap34xx check here?
Isn't this applicable to all omap & non-omap devices?
Thanks,
Vaibhav
> + /* If we are a secure device, remove any secure timer nodes */
> + if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
> + for_each_matching_node(np, omap3_timer_match) {
> + if (of_get_property(np, "ti,timer-secure", NULL))
> + prom_add_property(np, &timer_disabled);
> + }
> + }
> +}
> +
> /**
> * omap2_override_clocksource - clocksource override with user configuration
> *
>
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
2012-08-15 9:13 ` Vaibhav Hiremath
@ 2012-08-16 16:57 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-08-16 16:57 UTC (permalink / raw)
To: Vaibhav Hiremath
Cc: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley, device-tree, linux-omap, linux-arm
On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
>
>
> On 7/14/2012 3:56 AM, Jon Hunter wrote:
>> OMAP3 devices may or may not have security features enabled. Security enabled
>> devices are known as high-secure (HS) and devices without security are known as
>> general purpose (GP).
>>
>> For OMAP3 devices there are 12 general purpose timers available. On secure
>> devices the 12th timer is reserved for secure usage and so cannot be used by
>> the kernel, where as for a GP device it is available. We can detect the OMAP
>> device type, secure or GP, at runtime via an on-chip register. Today, when not
>> using DT, we do not register the 12th timer as a linux device if the device is
>> secure.
>>
>> When using device tree, device tree is going to register all the timer devices
>> it finds in the device tree blob. To prevent device tree from registering 12th
>> timer on a secure OMAP3 device we can add a status property to the timer
>> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
>> device has a property "ti,timer-secure" to indicate that it will not be
>> available on a secure device and so for secure OMAP3 devices, we search for
>> timers with this property and then disable them. Using the prom_add_property()
>> function to dynamically add a property was a recommended approach suggested by
>> Rob Herring [1].
>>
>> I have tested this on an OMAP3 GP device and faking it to pretend to be a
>> secure device to ensure that any timers marked with "ti,timer-secure" are not
>> registered on boot. I have also made sure that all timers are registered as
>> expected on a GP device by default.
>>
>> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
>>
>> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
>> ---
>> arch/arm/mach-omap2/board-generic.c | 1 +
>> arch/arm/mach-omap2/common.h | 1 +
>> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
>> 3 files changed, 38 insertions(+)
>>
>> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
>> index 6f93a20..20124d7 100644
>> --- a/arch/arm/mach-omap2/board-generic.c
>> +++ b/arch/arm/mach-omap2/board-generic.c
>> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
>> static void __init omap_generic_init(void)
>> {
>> omap_sdrc_init(NULL, NULL);
>> + omap_dmtimer_init();
>>
>> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
>> }
>> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
>> index 1f65b18..d6a4875 100644
>> --- a/arch/arm/mach-omap2/common.h
>> +++ b/arch/arm/mach-omap2/common.h
>> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
>> struct omap_sdrc_params *sdrc_cs1);
>> struct omap2_hsmmc_info;
>> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
>> +extern void omap_dmtimer_init(void);
>>
>> #endif /* __ASSEMBLER__ */
>> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
>> index 13d20c8..e3b9931 100644
>> --- a/arch/arm/mach-omap2/timer.c
>> +++ b/arch/arm/mach-omap2/timer.c
>> @@ -36,6 +36,7 @@
>> #include <linux/clocksource.h>
>> #include <linux/clockchips.h>
>> #include <linux/slab.h>
>> +#include <linux/of.h>
>>
>> #include <asm/mach/time.h>
>> #include <plat/dmtimer.h>
>> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
>> }
>> arch_initcall(omap2_dm_timer_init);
>>
>> +static struct property timer_disabled = {
>> + .name = "status",
>> + .length = sizeof("disabled"),
>> + .value = "disabled",
>> +};
>> +
>> +static struct of_device_id omap3_timer_match[] __initdata = {
>> + { .compatible = "ti,omap3-timer", },
>> + { }
>> +};
>> +
>> +/**
>> + * omap_dmtimer_init - initialisation function when device tree is used
>> + *
>> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
>> + * be used by the kernel as they are reserved. Therefore, to prevent the
>> + * kernel registering these devices remove them dynamically from the device
>> + * tree on boot.
>> + */
>> +void __init omap_dmtimer_init(void)
>> +{
>> + struct device_node *np;
>> +
>> + if (!cpu_is_omap34xx())
>> + return;
>> +
>
> Sorry for responding so late, but why only omap34xx check here?
> Isn't this applicable to all omap & non-omap devices?
It is only applicable to omap3 devices as far as omap is concerned.
By non-omap, you are referring to the AMxxx stuff?
Do AMxxx devices even support security (ie. secure boot and have secure
peripherals)? If not then this will work for AMxxx devices too.
Let me know if the changelog is not clear why this is needed for an
omap3 device.
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
@ 2012-08-16 16:57 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-08-16 16:57 UTC (permalink / raw)
To: linux-arm-kernel
On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
>
>
> On 7/14/2012 3:56 AM, Jon Hunter wrote:
>> OMAP3 devices may or may not have security features enabled. Security enabled
>> devices are known as high-secure (HS) and devices without security are known as
>> general purpose (GP).
>>
>> For OMAP3 devices there are 12 general purpose timers available. On secure
>> devices the 12th timer is reserved for secure usage and so cannot be used by
>> the kernel, where as for a GP device it is available. We can detect the OMAP
>> device type, secure or GP, at runtime via an on-chip register. Today, when not
>> using DT, we do not register the 12th timer as a linux device if the device is
>> secure.
>>
>> When using device tree, device tree is going to register all the timer devices
>> it finds in the device tree blob. To prevent device tree from registering 12th
>> timer on a secure OMAP3 device we can add a status property to the timer
>> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
>> device has a property "ti,timer-secure" to indicate that it will not be
>> available on a secure device and so for secure OMAP3 devices, we search for
>> timers with this property and then disable them. Using the prom_add_property()
>> function to dynamically add a property was a recommended approach suggested by
>> Rob Herring [1].
>>
>> I have tested this on an OMAP3 GP device and faking it to pretend to be a
>> secure device to ensure that any timers marked with "ti,timer-secure" are not
>> registered on boot. I have also made sure that all timers are registered as
>> expected on a GP device by default.
>>
>> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
>>
>> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
>> ---
>> arch/arm/mach-omap2/board-generic.c | 1 +
>> arch/arm/mach-omap2/common.h | 1 +
>> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
>> 3 files changed, 38 insertions(+)
>>
>> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
>> index 6f93a20..20124d7 100644
>> --- a/arch/arm/mach-omap2/board-generic.c
>> +++ b/arch/arm/mach-omap2/board-generic.c
>> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
>> static void __init omap_generic_init(void)
>> {
>> omap_sdrc_init(NULL, NULL);
>> + omap_dmtimer_init();
>>
>> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
>> }
>> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
>> index 1f65b18..d6a4875 100644
>> --- a/arch/arm/mach-omap2/common.h
>> +++ b/arch/arm/mach-omap2/common.h
>> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
>> struct omap_sdrc_params *sdrc_cs1);
>> struct omap2_hsmmc_info;
>> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
>> +extern void omap_dmtimer_init(void);
>>
>> #endif /* __ASSEMBLER__ */
>> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
>> index 13d20c8..e3b9931 100644
>> --- a/arch/arm/mach-omap2/timer.c
>> +++ b/arch/arm/mach-omap2/timer.c
>> @@ -36,6 +36,7 @@
>> #include <linux/clocksource.h>
>> #include <linux/clockchips.h>
>> #include <linux/slab.h>
>> +#include <linux/of.h>
>>
>> #include <asm/mach/time.h>
>> #include <plat/dmtimer.h>
>> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
>> }
>> arch_initcall(omap2_dm_timer_init);
>>
>> +static struct property timer_disabled = {
>> + .name = "status",
>> + .length = sizeof("disabled"),
>> + .value = "disabled",
>> +};
>> +
>> +static struct of_device_id omap3_timer_match[] __initdata = {
>> + { .compatible = "ti,omap3-timer", },
>> + { }
>> +};
>> +
>> +/**
>> + * omap_dmtimer_init - initialisation function when device tree is used
>> + *
>> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
>> + * be used by the kernel as they are reserved. Therefore, to prevent the
>> + * kernel registering these devices remove them dynamically from the device
>> + * tree on boot.
>> + */
>> +void __init omap_dmtimer_init(void)
>> +{
>> + struct device_node *np;
>> +
>> + if (!cpu_is_omap34xx())
>> + return;
>> +
>
> Sorry for responding so late, but why only omap34xx check here?
> Isn't this applicable to all omap & non-omap devices?
It is only applicable to omap3 devices as far as omap is concerned.
By non-omap, you are referring to the AMxxx stuff?
Do AMxxx devices even support security (ie. secure boot and have secure
peripherals)? If not then this will work for AMxxx devices too.
Let me know if the changelog is not clear why this is needed for an
omap3 device.
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread[parent not found: <502D2686.4090107-l0cyMroinI0@public.gmane.org>]
* RE: [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
2012-08-16 16:57 ` Jon Hunter
@ 2012-08-17 5:32 ` Hiremath, Vaibhav
-1 siblings, 0 replies; 65+ messages in thread
From: Hiremath, Vaibhav @ 2012-08-17 5:32 UTC (permalink / raw)
To: Hunter, Jon
Cc: device-tree, Rob Herring, linux-omap, DebBarma, Tarun Kanti, linux-arm
On Thu, Aug 16, 2012 at 22:27:42, Hunter, Jon wrote:
>
> On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
> >
> >
> > On 7/14/2012 3:56 AM, Jon Hunter wrote:
> >> OMAP3 devices may or may not have security features enabled. Security enabled
> >> devices are known as high-secure (HS) and devices without security are known as
> >> general purpose (GP).
> >>
> >> For OMAP3 devices there are 12 general purpose timers available. On secure
> >> devices the 12th timer is reserved for secure usage and so cannot be used by
> >> the kernel, where as for a GP device it is available. We can detect the OMAP
> >> device type, secure or GP, at runtime via an on-chip register. Today, when not
> >> using DT, we do not register the 12th timer as a linux device if the device is
> >> secure.
> >>
> >> When using device tree, device tree is going to register all the timer devices
> >> it finds in the device tree blob. To prevent device tree from registering 12th
> >> timer on a secure OMAP3 device we can add a status property to the timer
> >> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
> >> device has a property "ti,timer-secure" to indicate that it will not be
> >> available on a secure device and so for secure OMAP3 devices, we search for
> >> timers with this property and then disable them. Using the prom_add_property()
> >> function to dynamically add a property was a recommended approach suggested by
> >> Rob Herring [1].
> >>
> >> I have tested this on an OMAP3 GP device and faking it to pretend to be a
> >> secure device to ensure that any timers marked with "ti,timer-secure" are not
> >> registered on boot. I have also made sure that all timers are registered as
> >> expected on a GP device by default.
> >>
> >> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
> >>
> >> Signed-off-by: Jon Hunter <jon-hunter-l0cyMroinI0@public.gmane.org>
> >> ---
> >> arch/arm/mach-omap2/board-generic.c | 1 +
> >> arch/arm/mach-omap2/common.h | 1 +
> >> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
> >> 3 files changed, 38 insertions(+)
> >>
> >> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> >> index 6f93a20..20124d7 100644
> >> --- a/arch/arm/mach-omap2/board-generic.c
> >> +++ b/arch/arm/mach-omap2/board-generic.c
> >> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
> >> static void __init omap_generic_init(void)
> >> {
> >> omap_sdrc_init(NULL, NULL);
> >> + omap_dmtimer_init();
> >>
> >> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
> >> }
> >> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
> >> index 1f65b18..d6a4875 100644
> >> --- a/arch/arm/mach-omap2/common.h
> >> +++ b/arch/arm/mach-omap2/common.h
> >> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
> >> struct omap_sdrc_params *sdrc_cs1);
> >> struct omap2_hsmmc_info;
> >> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
> >> +extern void omap_dmtimer_init(void);
> >>
> >> #endif /* __ASSEMBLER__ */
> >> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
> >> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> >> index 13d20c8..e3b9931 100644
> >> --- a/arch/arm/mach-omap2/timer.c
> >> +++ b/arch/arm/mach-omap2/timer.c
> >> @@ -36,6 +36,7 @@
> >> #include <linux/clocksource.h>
> >> #include <linux/clockchips.h>
> >> #include <linux/slab.h>
> >> +#include <linux/of.h>
> >>
> >> #include <asm/mach/time.h>
> >> #include <plat/dmtimer.h>
> >> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
> >> }
> >> arch_initcall(omap2_dm_timer_init);
> >>
> >> +static struct property timer_disabled = {
> >> + .name = "status",
> >> + .length = sizeof("disabled"),
> >> + .value = "disabled",
> >> +};
> >> +
> >> +static struct of_device_id omap3_timer_match[] __initdata = {
> >> + { .compatible = "ti,omap3-timer", },
> >> + { }
> >> +};
> >> +
> >> +/**
> >> + * omap_dmtimer_init - initialisation function when device tree is used
> >> + *
> >> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
> >> + * be used by the kernel as they are reserved. Therefore, to prevent the
> >> + * kernel registering these devices remove them dynamically from the device
> >> + * tree on boot.
> >> + */
> >> +void __init omap_dmtimer_init(void)
> >> +{
> >> + struct device_node *np;
> >> +
> >> + if (!cpu_is_omap34xx())
> >> + return;
> >> +
> >
> > Sorry for responding so late, but why only omap34xx check here?
> > Isn't this applicable to all omap & non-omap devices?
>
> It is only applicable to omap3 devices as far as omap is concerned.
>
> By non-omap, you are referring to the AMxxx stuff?
>
> Do AMxxx devices even support security (ie. secure boot and have secure
> peripherals)? If not then this will work for AMxxx devices too.
>
Yes it does.
AM33xx has 8 timers and Timer-0 is a secure timer. As in case of OMAP3, we
do not even register timer-0 to kernel.
> Let me know if the changelog is not clear why this is needed for an
> omap3 device.
>
The changelog description is clear, but it is not only restricted to OMAP3.
Thanks,
Vaibhav
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
@ 2012-08-17 5:32 ` Hiremath, Vaibhav
0 siblings, 0 replies; 65+ messages in thread
From: Hiremath, Vaibhav @ 2012-08-17 5:32 UTC (permalink / raw)
To: linux-arm-kernel
On Thu, Aug 16, 2012 at 22:27:42, Hunter, Jon wrote:
>
> On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
> >
> >
> > On 7/14/2012 3:56 AM, Jon Hunter wrote:
> >> OMAP3 devices may or may not have security features enabled. Security enabled
> >> devices are known as high-secure (HS) and devices without security are known as
> >> general purpose (GP).
> >>
> >> For OMAP3 devices there are 12 general purpose timers available. On secure
> >> devices the 12th timer is reserved for secure usage and so cannot be used by
> >> the kernel, where as for a GP device it is available. We can detect the OMAP
> >> device type, secure or GP, at runtime via an on-chip register. Today, when not
> >> using DT, we do not register the 12th timer as a linux device if the device is
> >> secure.
> >>
> >> When using device tree, device tree is going to register all the timer devices
> >> it finds in the device tree blob. To prevent device tree from registering 12th
> >> timer on a secure OMAP3 device we can add a status property to the timer
> >> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
> >> device has a property "ti,timer-secure" to indicate that it will not be
> >> available on a secure device and so for secure OMAP3 devices, we search for
> >> timers with this property and then disable them. Using the prom_add_property()
> >> function to dynamically add a property was a recommended approach suggested by
> >> Rob Herring [1].
> >>
> >> I have tested this on an OMAP3 GP device and faking it to pretend to be a
> >> secure device to ensure that any timers marked with "ti,timer-secure" are not
> >> registered on boot. I have also made sure that all timers are registered as
> >> expected on a GP device by default.
> >>
> >> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
> >>
> >> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> >> ---
> >> arch/arm/mach-omap2/board-generic.c | 1 +
> >> arch/arm/mach-omap2/common.h | 1 +
> >> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
> >> 3 files changed, 38 insertions(+)
> >>
> >> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> >> index 6f93a20..20124d7 100644
> >> --- a/arch/arm/mach-omap2/board-generic.c
> >> +++ b/arch/arm/mach-omap2/board-generic.c
> >> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
> >> static void __init omap_generic_init(void)
> >> {
> >> omap_sdrc_init(NULL, NULL);
> >> + omap_dmtimer_init();
> >>
> >> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
> >> }
> >> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
> >> index 1f65b18..d6a4875 100644
> >> --- a/arch/arm/mach-omap2/common.h
> >> +++ b/arch/arm/mach-omap2/common.h
> >> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
> >> struct omap_sdrc_params *sdrc_cs1);
> >> struct omap2_hsmmc_info;
> >> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
> >> +extern void omap_dmtimer_init(void);
> >>
> >> #endif /* __ASSEMBLER__ */
> >> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
> >> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> >> index 13d20c8..e3b9931 100644
> >> --- a/arch/arm/mach-omap2/timer.c
> >> +++ b/arch/arm/mach-omap2/timer.c
> >> @@ -36,6 +36,7 @@
> >> #include <linux/clocksource.h>
> >> #include <linux/clockchips.h>
> >> #include <linux/slab.h>
> >> +#include <linux/of.h>
> >>
> >> #include <asm/mach/time.h>
> >> #include <plat/dmtimer.h>
> >> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
> >> }
> >> arch_initcall(omap2_dm_timer_init);
> >>
> >> +static struct property timer_disabled = {
> >> + .name = "status",
> >> + .length = sizeof("disabled"),
> >> + .value = "disabled",
> >> +};
> >> +
> >> +static struct of_device_id omap3_timer_match[] __initdata = {
> >> + { .compatible = "ti,omap3-timer", },
> >> + { }
> >> +};
> >> +
> >> +/**
> >> + * omap_dmtimer_init - initialisation function when device tree is used
> >> + *
> >> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
> >> + * be used by the kernel as they are reserved. Therefore, to prevent the
> >> + * kernel registering these devices remove them dynamically from the device
> >> + * tree on boot.
> >> + */
> >> +void __init omap_dmtimer_init(void)
> >> +{
> >> + struct device_node *np;
> >> +
> >> + if (!cpu_is_omap34xx())
> >> + return;
> >> +
> >
> > Sorry for responding so late, but why only omap34xx check here?
> > Isn't this applicable to all omap & non-omap devices?
>
> It is only applicable to omap3 devices as far as omap is concerned.
>
> By non-omap, you are referring to the AMxxx stuff?
>
> Do AMxxx devices even support security (ie. secure boot and have secure
> peripherals)? If not then this will work for AMxxx devices too.
>
Yes it does.
AM33xx has 8 timers and Timer-0 is a secure timer. As in case of OMAP3, we
do not even register timer-0 to kernel.
> Let me know if the changelog is not clear why this is needed for an
> omap3 device.
>
The changelog description is clear, but it is not only restricted to OMAP3.
Thanks,
Vaibhav
^ permalink raw reply [flat|nested] 65+ messages in thread* Re: [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
2012-08-17 5:32 ` Hiremath, Vaibhav
@ 2012-08-17 12:24 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-08-17 12:24 UTC (permalink / raw)
To: Hiremath, Vaibhav
Cc: DebBarma, Tarun Kanti, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley, device-tree, linux-omap, linux-arm
On 08/17/2012 12:32 AM, Hiremath, Vaibhav wrote:
> On Thu, Aug 16, 2012 at 22:27:42, Hunter, Jon wrote:
>>
>> On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
>>>
>>>
>>> On 7/14/2012 3:56 AM, Jon Hunter wrote:
>>>> OMAP3 devices may or may not have security features enabled. Security enabled
>>>> devices are known as high-secure (HS) and devices without security are known as
>>>> general purpose (GP).
>>>>
>>>> For OMAP3 devices there are 12 general purpose timers available. On secure
>>>> devices the 12th timer is reserved for secure usage and so cannot be used by
>>>> the kernel, where as for a GP device it is available. We can detect the OMAP
>>>> device type, secure or GP, at runtime via an on-chip register. Today, when not
>>>> using DT, we do not register the 12th timer as a linux device if the device is
>>>> secure.
>>>>
>>>> When using device tree, device tree is going to register all the timer devices
>>>> it finds in the device tree blob. To prevent device tree from registering 12th
>>>> timer on a secure OMAP3 device we can add a status property to the timer
>>>> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
>>>> device has a property "ti,timer-secure" to indicate that it will not be
>>>> available on a secure device and so for secure OMAP3 devices, we search for
>>>> timers with this property and then disable them. Using the prom_add_property()
>>>> function to dynamically add a property was a recommended approach suggested by
>>>> Rob Herring [1].
>>>>
>>>> I have tested this on an OMAP3 GP device and faking it to pretend to be a
>>>> secure device to ensure that any timers marked with "ti,timer-secure" are not
>>>> registered on boot. I have also made sure that all timers are registered as
>>>> expected on a GP device by default.
>>>>
>>>> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
>>>>
>>>> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
>>>> ---
>>>> arch/arm/mach-omap2/board-generic.c | 1 +
>>>> arch/arm/mach-omap2/common.h | 1 +
>>>> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
>>>> 3 files changed, 38 insertions(+)
>>>>
>>>> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
>>>> index 6f93a20..20124d7 100644
>>>> --- a/arch/arm/mach-omap2/board-generic.c
>>>> +++ b/arch/arm/mach-omap2/board-generic.c
>>>> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
>>>> static void __init omap_generic_init(void)
>>>> {
>>>> omap_sdrc_init(NULL, NULL);
>>>> + omap_dmtimer_init();
>>>>
>>>> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
>>>> }
>>>> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
>>>> index 1f65b18..d6a4875 100644
>>>> --- a/arch/arm/mach-omap2/common.h
>>>> +++ b/arch/arm/mach-omap2/common.h
>>>> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
>>>> struct omap_sdrc_params *sdrc_cs1);
>>>> struct omap2_hsmmc_info;
>>>> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
>>>> +extern void omap_dmtimer_init(void);
>>>>
>>>> #endif /* __ASSEMBLER__ */
>>>> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
>>>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
>>>> index 13d20c8..e3b9931 100644
>>>> --- a/arch/arm/mach-omap2/timer.c
>>>> +++ b/arch/arm/mach-omap2/timer.c
>>>> @@ -36,6 +36,7 @@
>>>> #include <linux/clocksource.h>
>>>> #include <linux/clockchips.h>
>>>> #include <linux/slab.h>
>>>> +#include <linux/of.h>
>>>>
>>>> #include <asm/mach/time.h>
>>>> #include <plat/dmtimer.h>
>>>> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
>>>> }
>>>> arch_initcall(omap2_dm_timer_init);
>>>>
>>>> +static struct property timer_disabled = {
>>>> + .name = "status",
>>>> + .length = sizeof("disabled"),
>>>> + .value = "disabled",
>>>> +};
>>>> +
>>>> +static struct of_device_id omap3_timer_match[] __initdata = {
>>>> + { .compatible = "ti,omap3-timer", },
>>>> + { }
>>>> +};
>>>> +
>>>> +/**
>>>> + * omap_dmtimer_init - initialisation function when device tree is used
>>>> + *
>>>> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
>>>> + * be used by the kernel as they are reserved. Therefore, to prevent the
>>>> + * kernel registering these devices remove them dynamically from the device
>>>> + * tree on boot.
>>>> + */
>>>> +void __init omap_dmtimer_init(void)
>>>> +{
>>>> + struct device_node *np;
>>>> +
>>>> + if (!cpu_is_omap34xx())
>>>> + return;
>>>> +
>>>
>>> Sorry for responding so late, but why only omap34xx check here?
>>> Isn't this applicable to all omap & non-omap devices?
>>
>> It is only applicable to omap3 devices as far as omap is concerned.
>>
>> By non-omap, you are referring to the AMxxx stuff?
>>
>> Do AMxxx devices even support security (ie. secure boot and have secure
>> peripherals)? If not then this will work for AMxxx devices too.
>>
>
> Yes it does.
>
> AM33xx has 8 timers and Timer-0 is a secure timer. As in case of OMAP3, we
> do not even register timer-0 to kernel.
Ok, however, please note that the omap3 timer 12 is a special case,
because on a non-secure device it is available for general purpose use
and only reserved for secure use on a secure device.
For omap4/5 timer 12 is always a secure timer and so we never register
it for any device (secure or non-secure) by using the "ti,timer-secure"
property in DT.
So, for AM33xx, is timer0 always reserved for secure used on non-secure
and secure devices? If so, then timer0 just needs to add the
"ti,timer-secure" property in device-tree file and it will not be
registered and no change is needed in the above code.
>> Let me know if the changelog is not clear why this is needed for an
>> omap3 device.
>>
>
> The changelog description is clear, but it is not only restricted to OMAP3.
Not exactly, per the above it depends on whether the timer is always
secure for all device types or not.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
@ 2012-08-17 12:24 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-08-17 12:24 UTC (permalink / raw)
To: linux-arm-kernel
On 08/17/2012 12:32 AM, Hiremath, Vaibhav wrote:
> On Thu, Aug 16, 2012 at 22:27:42, Hunter, Jon wrote:
>>
>> On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
>>>
>>>
>>> On 7/14/2012 3:56 AM, Jon Hunter wrote:
>>>> OMAP3 devices may or may not have security features enabled. Security enabled
>>>> devices are known as high-secure (HS) and devices without security are known as
>>>> general purpose (GP).
>>>>
>>>> For OMAP3 devices there are 12 general purpose timers available. On secure
>>>> devices the 12th timer is reserved for secure usage and so cannot be used by
>>>> the kernel, where as for a GP device it is available. We can detect the OMAP
>>>> device type, secure or GP, at runtime via an on-chip register. Today, when not
>>>> using DT, we do not register the 12th timer as a linux device if the device is
>>>> secure.
>>>>
>>>> When using device tree, device tree is going to register all the timer devices
>>>> it finds in the device tree blob. To prevent device tree from registering 12th
>>>> timer on a secure OMAP3 device we can add a status property to the timer
>>>> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
>>>> device has a property "ti,timer-secure" to indicate that it will not be
>>>> available on a secure device and so for secure OMAP3 devices, we search for
>>>> timers with this property and then disable them. Using the prom_add_property()
>>>> function to dynamically add a property was a recommended approach suggested by
>>>> Rob Herring [1].
>>>>
>>>> I have tested this on an OMAP3 GP device and faking it to pretend to be a
>>>> secure device to ensure that any timers marked with "ti,timer-secure" are not
>>>> registered on boot. I have also made sure that all timers are registered as
>>>> expected on a GP device by default.
>>>>
>>>> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
>>>>
>>>> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
>>>> ---
>>>> arch/arm/mach-omap2/board-generic.c | 1 +
>>>> arch/arm/mach-omap2/common.h | 1 +
>>>> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
>>>> 3 files changed, 38 insertions(+)
>>>>
>>>> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
>>>> index 6f93a20..20124d7 100644
>>>> --- a/arch/arm/mach-omap2/board-generic.c
>>>> +++ b/arch/arm/mach-omap2/board-generic.c
>>>> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
>>>> static void __init omap_generic_init(void)
>>>> {
>>>> omap_sdrc_init(NULL, NULL);
>>>> + omap_dmtimer_init();
>>>>
>>>> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
>>>> }
>>>> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
>>>> index 1f65b18..d6a4875 100644
>>>> --- a/arch/arm/mach-omap2/common.h
>>>> +++ b/arch/arm/mach-omap2/common.h
>>>> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
>>>> struct omap_sdrc_params *sdrc_cs1);
>>>> struct omap2_hsmmc_info;
>>>> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
>>>> +extern void omap_dmtimer_init(void);
>>>>
>>>> #endif /* __ASSEMBLER__ */
>>>> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
>>>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
>>>> index 13d20c8..e3b9931 100644
>>>> --- a/arch/arm/mach-omap2/timer.c
>>>> +++ b/arch/arm/mach-omap2/timer.c
>>>> @@ -36,6 +36,7 @@
>>>> #include <linux/clocksource.h>
>>>> #include <linux/clockchips.h>
>>>> #include <linux/slab.h>
>>>> +#include <linux/of.h>
>>>>
>>>> #include <asm/mach/time.h>
>>>> #include <plat/dmtimer.h>
>>>> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
>>>> }
>>>> arch_initcall(omap2_dm_timer_init);
>>>>
>>>> +static struct property timer_disabled = {
>>>> + .name = "status",
>>>> + .length = sizeof("disabled"),
>>>> + .value = "disabled",
>>>> +};
>>>> +
>>>> +static struct of_device_id omap3_timer_match[] __initdata = {
>>>> + { .compatible = "ti,omap3-timer", },
>>>> + { }
>>>> +};
>>>> +
>>>> +/**
>>>> + * omap_dmtimer_init - initialisation function when device tree is used
>>>> + *
>>>> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
>>>> + * be used by the kernel as they are reserved. Therefore, to prevent the
>>>> + * kernel registering these devices remove them dynamically from the device
>>>> + * tree on boot.
>>>> + */
>>>> +void __init omap_dmtimer_init(void)
>>>> +{
>>>> + struct device_node *np;
>>>> +
>>>> + if (!cpu_is_omap34xx())
>>>> + return;
>>>> +
>>>
>>> Sorry for responding so late, but why only omap34xx check here?
>>> Isn't this applicable to all omap & non-omap devices?
>>
>> It is only applicable to omap3 devices as far as omap is concerned.
>>
>> By non-omap, you are referring to the AMxxx stuff?
>>
>> Do AMxxx devices even support security (ie. secure boot and have secure
>> peripherals)? If not then this will work for AMxxx devices too.
>>
>
> Yes it does.
>
> AM33xx has 8 timers and Timer-0 is a secure timer. As in case of OMAP3, we
> do not even register timer-0 to kernel.
Ok, however, please note that the omap3 timer 12 is a special case,
because on a non-secure device it is available for general purpose use
and only reserved for secure use on a secure device.
For omap4/5 timer 12 is always a secure timer and so we never register
it for any device (secure or non-secure) by using the "ti,timer-secure"
property in DT.
So, for AM33xx, is timer0 always reserved for secure used on non-secure
and secure devices? If so, then timer0 just needs to add the
"ti,timer-secure" property in device-tree file and it will not be
registered and no change is needed in the above code.
>> Let me know if the changelog is not clear why this is needed for an
>> omap3 device.
>>
>
> The changelog description is clear, but it is not only restricted to OMAP3.
Not exactly, per the above it depends on whether the timer is always
secure for all device types or not.
Cheers
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread* RE: [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
2012-08-17 12:24 ` Jon Hunter
@ 2012-08-24 15:56 ` Hiremath, Vaibhav
-1 siblings, 0 replies; 65+ messages in thread
From: Hiremath, Vaibhav @ 2012-08-24 15:56 UTC (permalink / raw)
To: Hunter, Jon
Cc: DebBarma, Tarun Kanti, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley, device-tree, linux-omap, linux-arm
On Fri, Aug 17, 2012 at 17:54:09, Hunter, Jon wrote:
>
> On 08/17/2012 12:32 AM, Hiremath, Vaibhav wrote:
> > On Thu, Aug 16, 2012 at 22:27:42, Hunter, Jon wrote:
> >>
> >> On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
> >>>
> >>>
> >>> On 7/14/2012 3:56 AM, Jon Hunter wrote:
> >>>> OMAP3 devices may or may not have security features enabled. Security enabled
> >>>> devices are known as high-secure (HS) and devices without security are known as
> >>>> general purpose (GP).
> >>>>
> >>>> For OMAP3 devices there are 12 general purpose timers available. On secure
> >>>> devices the 12th timer is reserved for secure usage and so cannot be used by
> >>>> the kernel, where as for a GP device it is available. We can detect the OMAP
> >>>> device type, secure or GP, at runtime via an on-chip register. Today, when not
> >>>> using DT, we do not register the 12th timer as a linux device if the device is
> >>>> secure.
> >>>>
> >>>> When using device tree, device tree is going to register all the timer devices
> >>>> it finds in the device tree blob. To prevent device tree from registering 12th
> >>>> timer on a secure OMAP3 device we can add a status property to the timer
> >>>> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
> >>>> device has a property "ti,timer-secure" to indicate that it will not be
> >>>> available on a secure device and so for secure OMAP3 devices, we search for
> >>>> timers with this property and then disable them. Using the prom_add_property()
> >>>> function to dynamically add a property was a recommended approach suggested by
> >>>> Rob Herring [1].
> >>>>
> >>>> I have tested this on an OMAP3 GP device and faking it to pretend to be a
> >>>> secure device to ensure that any timers marked with "ti,timer-secure" are not
> >>>> registered on boot. I have also made sure that all timers are registered as
> >>>> expected on a GP device by default.
> >>>>
> >>>> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
> >>>>
> >>>> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> >>>> ---
> >>>> arch/arm/mach-omap2/board-generic.c | 1 +
> >>>> arch/arm/mach-omap2/common.h | 1 +
> >>>> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
> >>>> 3 files changed, 38 insertions(+)
> >>>>
> >>>> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> >>>> index 6f93a20..20124d7 100644
> >>>> --- a/arch/arm/mach-omap2/board-generic.c
> >>>> +++ b/arch/arm/mach-omap2/board-generic.c
> >>>> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
> >>>> static void __init omap_generic_init(void)
> >>>> {
> >>>> omap_sdrc_init(NULL, NULL);
> >>>> + omap_dmtimer_init();
> >>>>
> >>>> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
> >>>> }
> >>>> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
> >>>> index 1f65b18..d6a4875 100644
> >>>> --- a/arch/arm/mach-omap2/common.h
> >>>> +++ b/arch/arm/mach-omap2/common.h
> >>>> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
> >>>> struct omap_sdrc_params *sdrc_cs1);
> >>>> struct omap2_hsmmc_info;
> >>>> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
> >>>> +extern void omap_dmtimer_init(void);
> >>>>
> >>>> #endif /* __ASSEMBLER__ */
> >>>> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
> >>>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> >>>> index 13d20c8..e3b9931 100644
> >>>> --- a/arch/arm/mach-omap2/timer.c
> >>>> +++ b/arch/arm/mach-omap2/timer.c
> >>>> @@ -36,6 +36,7 @@
> >>>> #include <linux/clocksource.h>
> >>>> #include <linux/clockchips.h>
> >>>> #include <linux/slab.h>
> >>>> +#include <linux/of.h>
> >>>>
> >>>> #include <asm/mach/time.h>
> >>>> #include <plat/dmtimer.h>
> >>>> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
> >>>> }
> >>>> arch_initcall(omap2_dm_timer_init);
> >>>>
> >>>> +static struct property timer_disabled = {
> >>>> + .name = "status",
> >>>> + .length = sizeof("disabled"),
> >>>> + .value = "disabled",
> >>>> +};
> >>>> +
> >>>> +static struct of_device_id omap3_timer_match[] __initdata = {
> >>>> + { .compatible = "ti,omap3-timer", },
> >>>> + { }
> >>>> +};
> >>>> +
> >>>> +/**
> >>>> + * omap_dmtimer_init - initialisation function when device tree is used
> >>>> + *
> >>>> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
> >>>> + * be used by the kernel as they are reserved. Therefore, to prevent the
> >>>> + * kernel registering these devices remove them dynamically from the device
> >>>> + * tree on boot.
> >>>> + */
> >>>> +void __init omap_dmtimer_init(void)
> >>>> +{
> >>>> + struct device_node *np;
> >>>> +
> >>>> + if (!cpu_is_omap34xx())
> >>>> + return;
> >>>> +
> >>>
> >>> Sorry for responding so late, but why only omap34xx check here?
> >>> Isn't this applicable to all omap & non-omap devices?
> >>
> >> It is only applicable to omap3 devices as far as omap is concerned.
> >>
> >> By non-omap, you are referring to the AMxxx stuff?
> >>
> >> Do AMxxx devices even support security (ie. secure boot and have secure
> >> peripherals)? If not then this will work for AMxxx devices too.
> >>
> >
> > Yes it does.
> >
> > AM33xx has 8 timers and Timer-0 is a secure timer. As in case of OMAP3, we
> > do not even register timer-0 to kernel.
>
> Ok, however, please note that the omap3 timer 12 is a special case,
> because on a non-secure device it is available for general purpose use
> and only reserved for secure use on a secure device.
>
> For omap4/5 timer 12 is always a secure timer and so we never register
> it for any device (secure or non-secure) by using the "ti,timer-secure"
> property in DT.
>
> So, for AM33xx, is timer0 always reserved for secure used on non-secure
> and secure devices? If so, then timer0 just needs to add the
> "ti,timer-secure" property in device-tree file and it will not be
> registered and no change is needed in the above code.
>
I think you may be right here, AM33XX secure timer is similar to omap4, so
Just "ti,timer-secure" property should be enough.
Thanks,
Vaibhav
^ permalink raw reply [flat|nested] 65+ messages in thread* [RFC RESEND 2/4] ARM: OMAP3: Dynamically disable secure timer nodes for secure devices
@ 2012-08-24 15:56 ` Hiremath, Vaibhav
0 siblings, 0 replies; 65+ messages in thread
From: Hiremath, Vaibhav @ 2012-08-24 15:56 UTC (permalink / raw)
To: linux-arm-kernel
On Fri, Aug 17, 2012 at 17:54:09, Hunter, Jon wrote:
>
> On 08/17/2012 12:32 AM, Hiremath, Vaibhav wrote:
> > On Thu, Aug 16, 2012 at 22:27:42, Hunter, Jon wrote:
> >>
> >> On 08/15/2012 04:13 AM, Vaibhav Hiremath wrote:
> >>>
> >>>
> >>> On 7/14/2012 3:56 AM, Jon Hunter wrote:
> >>>> OMAP3 devices may or may not have security features enabled. Security enabled
> >>>> devices are known as high-secure (HS) and devices without security are known as
> >>>> general purpose (GP).
> >>>>
> >>>> For OMAP3 devices there are 12 general purpose timers available. On secure
> >>>> devices the 12th timer is reserved for secure usage and so cannot be used by
> >>>> the kernel, where as for a GP device it is available. We can detect the OMAP
> >>>> device type, secure or GP, at runtime via an on-chip register. Today, when not
> >>>> using DT, we do not register the 12th timer as a linux device if the device is
> >>>> secure.
> >>>>
> >>>> When using device tree, device tree is going to register all the timer devices
> >>>> it finds in the device tree blob. To prevent device tree from registering 12th
> >>>> timer on a secure OMAP3 device we can add a status property to the timer
> >>>> binding with the value "disabled" at boot time. Note that timer 12 on a OMAP3
> >>>> device has a property "ti,timer-secure" to indicate that it will not be
> >>>> available on a secure device and so for secure OMAP3 devices, we search for
> >>>> timers with this property and then disable them. Using the prom_add_property()
> >>>> function to dynamically add a property was a recommended approach suggested by
> >>>> Rob Herring [1].
> >>>>
> >>>> I have tested this on an OMAP3 GP device and faking it to pretend to be a
> >>>> secure device to ensure that any timers marked with "ti,timer-secure" are not
> >>>> registered on boot. I have also made sure that all timers are registered as
> >>>> expected on a GP device by default.
> >>>>
> >>>> [1] http://comments.gmane.org/gmane.linux.ports.arm.omap/79203
> >>>>
> >>>> Signed-off-by: Jon Hunter <jon-hunter@ti.com>
> >>>> ---
> >>>> arch/arm/mach-omap2/board-generic.c | 1 +
> >>>> arch/arm/mach-omap2/common.h | 1 +
> >>>> arch/arm/mach-omap2/timer.c | 36 +++++++++++++++++++++++++++++++++++
> >>>> 3 files changed, 38 insertions(+)
> >>>>
> >>>> diff --git a/arch/arm/mach-omap2/board-generic.c b/arch/arm/mach-omap2/board-generic.c
> >>>> index 6f93a20..20124d7 100644
> >>>> --- a/arch/arm/mach-omap2/board-generic.c
> >>>> +++ b/arch/arm/mach-omap2/board-generic.c
> >>>> @@ -40,6 +40,7 @@ static struct of_device_id omap_dt_match_table[] __initdata = {
> >>>> static void __init omap_generic_init(void)
> >>>> {
> >>>> omap_sdrc_init(NULL, NULL);
> >>>> + omap_dmtimer_init();
> >>>>
> >>>> of_platform_populate(NULL, omap_dt_match_table, NULL, NULL);
> >>>> }
> >>>> diff --git a/arch/arm/mach-omap2/common.h b/arch/arm/mach-omap2/common.h
> >>>> index 1f65b18..d6a4875 100644
> >>>> --- a/arch/arm/mach-omap2/common.h
> >>>> +++ b/arch/arm/mach-omap2/common.h
> >>>> @@ -326,6 +326,7 @@ extern void omap_sdrc_init(struct omap_sdrc_params *sdrc_cs0,
> >>>> struct omap_sdrc_params *sdrc_cs1);
> >>>> struct omap2_hsmmc_info;
> >>>> extern int omap4_twl6030_hsmmc_init(struct omap2_hsmmc_info *controllers);
> >>>> +extern void omap_dmtimer_init(void);
> >>>>
> >>>> #endif /* __ASSEMBLER__ */
> >>>> #endif /* __ARCH_ARM_MACH_OMAP2PLUS_COMMON_H */
> >>>> diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
> >>>> index 13d20c8..e3b9931 100644
> >>>> --- a/arch/arm/mach-omap2/timer.c
> >>>> +++ b/arch/arm/mach-omap2/timer.c
> >>>> @@ -36,6 +36,7 @@
> >>>> #include <linux/clocksource.h>
> >>>> #include <linux/clockchips.h>
> >>>> #include <linux/slab.h>
> >>>> +#include <linux/of.h>
> >>>>
> >>>> #include <asm/mach/time.h>
> >>>> #include <plat/dmtimer.h>
> >>>> @@ -482,6 +483,41 @@ static int __init omap2_dm_timer_init(void)
> >>>> }
> >>>> arch_initcall(omap2_dm_timer_init);
> >>>>
> >>>> +static struct property timer_disabled = {
> >>>> + .name = "status",
> >>>> + .length = sizeof("disabled"),
> >>>> + .value = "disabled",
> >>>> +};
> >>>> +
> >>>> +static struct of_device_id omap3_timer_match[] __initdata = {
> >>>> + { .compatible = "ti,omap3-timer", },
> >>>> + { }
> >>>> +};
> >>>> +
> >>>> +/**
> >>>> + * omap_dmtimer_init - initialisation function when device tree is used
> >>>> + *
> >>>> + * For secure OMAP3 devices, timers with device type "timer-secure" cannot
> >>>> + * be used by the kernel as they are reserved. Therefore, to prevent the
> >>>> + * kernel registering these devices remove them dynamically from the device
> >>>> + * tree on boot.
> >>>> + */
> >>>> +void __init omap_dmtimer_init(void)
> >>>> +{
> >>>> + struct device_node *np;
> >>>> +
> >>>> + if (!cpu_is_omap34xx())
> >>>> + return;
> >>>> +
> >>>
> >>> Sorry for responding so late, but why only omap34xx check here?
> >>> Isn't this applicable to all omap & non-omap devices?
> >>
> >> It is only applicable to omap3 devices as far as omap is concerned.
> >>
> >> By non-omap, you are referring to the AMxxx stuff?
> >>
> >> Do AMxxx devices even support security (ie. secure boot and have secure
> >> peripherals)? If not then this will work for AMxxx devices too.
> >>
> >
> > Yes it does.
> >
> > AM33xx has 8 timers and Timer-0 is a secure timer. As in case of OMAP3, we
> > do not even register timer-0 to kernel.
>
> Ok, however, please note that the omap3 timer 12 is a special case,
> because on a non-secure device it is available for general purpose use
> and only reserved for secure use on a secure device.
>
> For omap4/5 timer 12 is always a secure timer and so we never register
> it for any device (secure or non-secure) by using the "ti,timer-secure"
> property in DT.
>
> So, for AM33xx, is timer0 always reserved for secure used on non-secure
> and secure devices? If so, then timer0 just needs to add the
> "ti,timer-secure" property in device-tree file and it will not be
> registered and no change is needed in the above code.
>
I think you may be right here, AM33XX secure timer is similar to omap4, so
Just "ti,timer-secure" property should be enough.
Thanks,
Vaibhav
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 3/4] ARM: OMAP4: Add timer clock aliases for device-tree
2012-07-13 22:26 ` Jon Hunter
@ 2012-07-13 22:26 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley
Cc: Benoit Cousson, linux-omap, linux-arm, device-tree, Jon Hunter
For OMAP4, the dmtimers are located in the Wake-up, ABE and Peripheral (PER)
power domains. Hence, when the dmtimer is configured to use the "timer_sys_ck"
as its functional clock the actual clock used is different depending on whether
the clock is in the Wake-up, ABE or PER domain. So when we look-up the dmtimer's
"timer_sys_ck" we need to specify the timer device name as well as clock alias
to find the right clock.
Currently, the device names for the timers have the format "omap_timer.X" where
X is the timer instance number. When using to device tree, the format of the
device name created by device-tree is different and has the format
"<reg-address>.<device-name>" (this is assuming that the device-tree "reg"
property is specified). This causes the look-up for the OMAP4 "timer_sys_ck" to
fail. To fix this add new timer clock alias for using device-tree.
Please note that adding a 2nd set of clock aliases for the same clocks to only
temporary until device-tree migration is complete. Then we can remove the legacy
aliases. Hence, I have marked the legacy aliases with a "TODO" to remove them.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
arch/arm/mach-omap2/clock44xx_data.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/arch/arm/mach-omap2/clock44xx_data.c b/arch/arm/mach-omap2/clock44xx_data.c
index d7f55e4..7dfeaf0 100644
--- a/arch/arm/mach-omap2/clock44xx_data.c
+++ b/arch/arm/mach-omap2/clock44xx_data.c
@@ -3314,6 +3314,7 @@ static struct omap_clk omap44xx_clks[] = {
CLK("usbhs_omap", "usbtll_fck", &dummy_ck, CK_443X),
CLK("omap_wdt", "ick", &dummy_ck, CK_443X),
CLK(NULL, "timer_32k_ck", &sys_32k_ck, CK_443X),
+ /* TODO: Remove "omap_timer.X" aliases once DT migration is complete */
CLK("omap_timer.1", "timer_sys_ck", &sys_clkin_ck, CK_443X),
CLK("omap_timer.2", "timer_sys_ck", &sys_clkin_ck, CK_443X),
CLK("omap_timer.3", "timer_sys_ck", &sys_clkin_ck, CK_443X),
@@ -3325,6 +3326,17 @@ static struct omap_clk omap44xx_clks[] = {
CLK("omap_timer.6", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
CLK("omap_timer.7", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
CLK("omap_timer.8", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4a318000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48032000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48034000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48036000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("4803e000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48086000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48088000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("49038000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4903a000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4903c000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4903e000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
};
int __init omap4xxx_clk_init(void)
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* [RFC RESEND 3/4] ARM: OMAP4: Add timer clock aliases for device-tree
@ 2012-07-13 22:26 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: linux-arm-kernel
For OMAP4, the dmtimers are located in the Wake-up, ABE and Peripheral (PER)
power domains. Hence, when the dmtimer is configured to use the "timer_sys_ck"
as its functional clock the actual clock used is different depending on whether
the clock is in the Wake-up, ABE or PER domain. So when we look-up the dmtimer's
"timer_sys_ck" we need to specify the timer device name as well as clock alias
to find the right clock.
Currently, the device names for the timers have the format "omap_timer.X" where
X is the timer instance number. When using to device tree, the format of the
device name created by device-tree is different and has the format
"<reg-address>.<device-name>" (this is assuming that the device-tree "reg"
property is specified). This causes the look-up for the OMAP4 "timer_sys_ck" to
fail. To fix this add new timer clock alias for using device-tree.
Please note that adding a 2nd set of clock aliases for the same clocks to only
temporary until device-tree migration is complete. Then we can remove the legacy
aliases. Hence, I have marked the legacy aliases with a "TODO" to remove them.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
arch/arm/mach-omap2/clock44xx_data.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/arch/arm/mach-omap2/clock44xx_data.c b/arch/arm/mach-omap2/clock44xx_data.c
index d7f55e4..7dfeaf0 100644
--- a/arch/arm/mach-omap2/clock44xx_data.c
+++ b/arch/arm/mach-omap2/clock44xx_data.c
@@ -3314,6 +3314,7 @@ static struct omap_clk omap44xx_clks[] = {
CLK("usbhs_omap", "usbtll_fck", &dummy_ck, CK_443X),
CLK("omap_wdt", "ick", &dummy_ck, CK_443X),
CLK(NULL, "timer_32k_ck", &sys_32k_ck, CK_443X),
+ /* TODO: Remove "omap_timer.X" aliases once DT migration is complete */
CLK("omap_timer.1", "timer_sys_ck", &sys_clkin_ck, CK_443X),
CLK("omap_timer.2", "timer_sys_ck", &sys_clkin_ck, CK_443X),
CLK("omap_timer.3", "timer_sys_ck", &sys_clkin_ck, CK_443X),
@@ -3325,6 +3326,17 @@ static struct omap_clk omap44xx_clks[] = {
CLK("omap_timer.6", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
CLK("omap_timer.7", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
CLK("omap_timer.8", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4a318000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48032000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48034000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48036000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("4803e000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48086000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("48088000.timer", "timer_sys_ck", &sys_clkin_ck, CK_443X),
+ CLK("49038000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4903a000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4903c000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
+ CLK("4903e000.timer", "timer_sys_ck", &syc_clk_div_ck, CK_443X),
};
int __init omap4xxx_clk_init(void)
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread
* [RFC RESEND 4/4] ARM: OMAP: Add DT support for timer driver
2012-07-13 22:26 ` Jon Hunter
@ 2012-07-13 22:26 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Paul Walmsley
Cc: Benoit Cousson, linux-omap, linux-arm, device-tree, Jon Hunter
In order to add device-tree support to the timer driver the following changes
were made ...
1. If DT blob is present, then let HWMOD create the timer devices dynamically.
2. When device-tree is present the "id" field in the platform_device structure
(pdev->id) is initialised to -1 and the timer instance is looked-up using the
device tree alias mechanism. Therefore, avoid using "pdev-id" in the driver
and use "timer->id" which will be initialised correctly regardless of whether
device tree is present.
3. When device-tree is present the platform_data structure will be NULL and so
check for this.
4. The OMAP timer device tree binding optional parameters ...
a. ti,timer-alwon --> Timer is in an always-on power domain
b. ti,timer-pwn --> Timer can generate a PWM output
Search for the above parameters and set the appropriate timer attribute
flags.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
arch/arm/mach-omap2/timer.c | 4 ++++
arch/arm/plat-omap/dmtimer.c | 32 ++++++++++++++++++++++++++------
2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index e3b9931..ad5b29a 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -473,6 +473,10 @@ static int __init omap2_dm_timer_init(void)
{
int ret;
+ /* If dtb is there, the devices will be created dynamically */
+ if (of_have_populated_dt())
+ return -ENODEV;
+
ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL);
if (unlikely(ret)) {
pr_err("%s: device registration failed.\n", __func__);
diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 626ad8c..5a51b67 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -40,6 +40,8 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <plat/dmtimer.h>
#include <plat/omap-pm.h>
@@ -123,7 +125,7 @@ static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
static void omap_dm_timer_reset(struct omap_dm_timer *timer)
{
omap_dm_timer_enable(timer);
- if (timer->pdev->id != 1) {
+ if (timer->id != 1) {
omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
omap_dm_timer_wait_for_reset(timer);
}
@@ -214,7 +216,7 @@ struct omap_dm_timer *omap_dm_timer_request_specific(int id)
spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(t, &omap_timer_list, node) {
- if (t->pdev->id == id && !t->reserved) {
+ if (t->id == id && !t->reserved) {
timer = t;
timer->reserved = 1;
break;
@@ -414,7 +416,7 @@ int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
* use the clock framework to set the parent clock. To be removed
* once OMAP1 migrated to using clock framework for dmtimers
*/
- if (pdata->set_timer_src)
+ if (pdata && pdata->set_timer_src)
return pdata->set_timer_src(timer->pdev, source);
fclk = clk_get(&timer->pdev->dev, "fck");
@@ -695,7 +697,7 @@ static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
- if (!pdata) {
+ if (!pdata && !dev->of_node) {
dev_err(dev, "%s: no platform data.\n", __func__);
return -ENODEV;
}
@@ -724,11 +726,21 @@ static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
return -ENOMEM;
}
- timer->id = pdev->id;
+ if (dev->of_node) {
+ timer->id = of_alias_get_id(dev->of_node, "timer");
+
+ if (of_find_property(dev->of_node, "ti,timer-alwon", NULL))
+ timer->capability |= OMAP_TIMER_ALWON;
+ if (of_find_property(dev->of_node, "ti,timer-pwm", NULL))
+ timer->capability |= OMAP_TIMER_HAS_PWM;
+ } else {
+ timer->id = pdev->id;
+ timer->capability = pdata->timer_capability;
+ }
+
timer->irq = irq->start;
timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
timer->pdev = pdev;
- timer->capability = pdata->timer_capability;
/* Skip pm_runtime_enable for OMAP1 */
if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
@@ -778,11 +790,19 @@ static int __devexit omap_dm_timer_remove(struct platform_device *pdev)
return ret;
}
+static const struct of_device_id omap_timer_match[] = {
+ { .compatible = "ti,omap3-timer", },
+ { .compatible = "ti,omap2-timer", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, omap_timer_match);
+
static struct platform_driver omap_dm_timer_driver = {
.probe = omap_dm_timer_probe,
.remove = __devexit_p(omap_dm_timer_remove),
.driver = {
.name = "omap_timer",
+ .of_match_table = of_match_ptr(omap_timer_match),
},
};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* [RFC RESEND 4/4] ARM: OMAP: Add DT support for timer driver
@ 2012-07-13 22:26 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-13 22:26 UTC (permalink / raw)
To: linux-arm-kernel
In order to add device-tree support to the timer driver the following changes
were made ...
1. If DT blob is present, then let HWMOD create the timer devices dynamically.
2. When device-tree is present the "id" field in the platform_device structure
(pdev->id) is initialised to -1 and the timer instance is looked-up using the
device tree alias mechanism. Therefore, avoid using "pdev-id" in the driver
and use "timer->id" which will be initialised correctly regardless of whether
device tree is present.
3. When device-tree is present the platform_data structure will be NULL and so
check for this.
4. The OMAP timer device tree binding optional parameters ...
a. ti,timer-alwon --> Timer is in an always-on power domain
b. ti,timer-pwn --> Timer can generate a PWM output
Search for the above parameters and set the appropriate timer attribute
flags.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
---
arch/arm/mach-omap2/timer.c | 4 ++++
arch/arm/plat-omap/dmtimer.c | 32 ++++++++++++++++++++++++++------
2 files changed, 30 insertions(+), 6 deletions(-)
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
index e3b9931..ad5b29a 100644
--- a/arch/arm/mach-omap2/timer.c
+++ b/arch/arm/mach-omap2/timer.c
@@ -473,6 +473,10 @@ static int __init omap2_dm_timer_init(void)
{
int ret;
+ /* If dtb is there, the devices will be created dynamically */
+ if (of_have_populated_dt())
+ return -ENODEV;
+
ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL);
if (unlikely(ret)) {
pr_err("%s: device registration failed.\n", __func__);
diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 626ad8c..5a51b67 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -40,6 +40,8 @@
#include <linux/device.h>
#include <linux/err.h>
#include <linux/pm_runtime.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
#include <plat/dmtimer.h>
#include <plat/omap-pm.h>
@@ -123,7 +125,7 @@ static void omap_dm_timer_wait_for_reset(struct omap_dm_timer *timer)
static void omap_dm_timer_reset(struct omap_dm_timer *timer)
{
omap_dm_timer_enable(timer);
- if (timer->pdev->id != 1) {
+ if (timer->id != 1) {
omap_dm_timer_write_reg(timer, OMAP_TIMER_IF_CTRL_REG, 0x06);
omap_dm_timer_wait_for_reset(timer);
}
@@ -214,7 +216,7 @@ struct omap_dm_timer *omap_dm_timer_request_specific(int id)
spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(t, &omap_timer_list, node) {
- if (t->pdev->id == id && !t->reserved) {
+ if (t->id == id && !t->reserved) {
timer = t;
timer->reserved = 1;
break;
@@ -414,7 +416,7 @@ int omap_dm_timer_set_source(struct omap_dm_timer *timer, int source)
* use the clock framework to set the parent clock. To be removed
* once OMAP1 migrated to using clock framework for dmtimers
*/
- if (pdata->set_timer_src)
+ if (pdata && pdata->set_timer_src)
return pdata->set_timer_src(timer->pdev, source);
fclk = clk_get(&timer->pdev->dev, "fck");
@@ -695,7 +697,7 @@ static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
- if (!pdata) {
+ if (!pdata && !dev->of_node) {
dev_err(dev, "%s: no platform data.\n", __func__);
return -ENODEV;
}
@@ -724,11 +726,21 @@ static int __devinit omap_dm_timer_probe(struct platform_device *pdev)
return -ENOMEM;
}
- timer->id = pdev->id;
+ if (dev->of_node) {
+ timer->id = of_alias_get_id(dev->of_node, "timer");
+
+ if (of_find_property(dev->of_node, "ti,timer-alwon", NULL))
+ timer->capability |= OMAP_TIMER_ALWON;
+ if (of_find_property(dev->of_node, "ti,timer-pwm", NULL))
+ timer->capability |= OMAP_TIMER_HAS_PWM;
+ } else {
+ timer->id = pdev->id;
+ timer->capability = pdata->timer_capability;
+ }
+
timer->irq = irq->start;
timer->reserved = omap_dm_timer_reserved_systimer(timer->id);
timer->pdev = pdev;
- timer->capability = pdata->timer_capability;
/* Skip pm_runtime_enable for OMAP1 */
if (!(timer->capability & OMAP_TIMER_NEEDS_RESET)) {
@@ -778,11 +790,19 @@ static int __devexit omap_dm_timer_remove(struct platform_device *pdev)
return ret;
}
+static const struct of_device_id omap_timer_match[] = {
+ { .compatible = "ti,omap3-timer", },
+ { .compatible = "ti,omap2-timer", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, omap_timer_match);
+
static struct platform_driver omap_dm_timer_driver = {
.probe = omap_dm_timer_probe,
.remove = __devexit_p(omap_dm_timer_remove),
.driver = {
.name = "omap_timer",
+ .of_match_table = of_match_ptr(omap_timer_match),
},
};
--
1.7.9.5
^ permalink raw reply related [flat|nested] 65+ messages in thread* Re: [RFC RESEND 4/4] ARM: OMAP: Add DT support for timer driver
2012-07-13 22:26 ` Jon Hunter
@ 2012-07-13 23:41 ` Paul Walmsley
-1 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-13 23:41 UTC (permalink / raw)
To: Jon Hunter
Cc: Tarun Kanti DebBarma, Tony Lindgren, Rob Herring, Grant Likely,
Benoit Cousson, linux-omap, linux-arm, device-tree
Hi
On Fri, 13 Jul 2012, Jon Hunter wrote:
> 1. If DT blob is present, then let HWMOD create the timer devices dynamically.
This probably should read "is _not_ present", yes?
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 4/4] ARM: OMAP: Add DT support for timer driver
@ 2012-07-13 23:41 ` Paul Walmsley
0 siblings, 0 replies; 65+ messages in thread
From: Paul Walmsley @ 2012-07-13 23:41 UTC (permalink / raw)
To: linux-arm-kernel
Hi
On Fri, 13 Jul 2012, Jon Hunter wrote:
> 1. If DT blob is present, then let HWMOD create the timer devices dynamically.
This probably should read "is _not_ present", yes?
- Paul
^ permalink raw reply [flat|nested] 65+ messages in thread
[parent not found: <alpine.DEB.2.00.1207131740460.25585-rwI8Ez+7Ko+d5PgPZx9QOdBPR1lH4CV8@public.gmane.org>]
* Re: [RFC RESEND 4/4] ARM: OMAP: Add DT support for timer driver
2012-07-13 23:41 ` Paul Walmsley
@ 2012-07-14 0:57 ` Jon Hunter
-1 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-14 0:57 UTC (permalink / raw)
To: Paul Walmsley
Cc: device-tree, Rob Herring, linux-omap, Tarun Kanti DebBarma, linux-arm
On 07/13/2012 06:41 PM, Paul Walmsley wrote:
> Hi
>
> On Fri, 13 Jul 2012, Jon Hunter wrote:
>
>> 1. If DT blob is present, then let HWMOD create the timer devices dynamically.
>
> This probably should read "is _not_ present", yes?
Yes, you are right. What a balls-up ...
Thanks
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread
* [RFC RESEND 4/4] ARM: OMAP: Add DT support for timer driver
@ 2012-07-14 0:57 ` Jon Hunter
0 siblings, 0 replies; 65+ messages in thread
From: Jon Hunter @ 2012-07-14 0:57 UTC (permalink / raw)
To: linux-arm-kernel
On 07/13/2012 06:41 PM, Paul Walmsley wrote:
> Hi
>
> On Fri, 13 Jul 2012, Jon Hunter wrote:
>
>> 1. If DT blob is present, then let HWMOD create the timer devices dynamically.
>
> This probably should read "is _not_ present", yes?
Yes, you are right. What a balls-up ...
Thanks
Jon
^ permalink raw reply [flat|nested] 65+ messages in thread