Re: [PATCH 1/6] dt-bindings: timer: add Tegra210 timer
From: Joseph Lo <hidden>
Date: 2019-01-28 03:09:42
Also in:
linux-devicetree, linux-tegra, lkml
On 1/25/19 8:01 PM, Jon Hunter wrote:
On 25/01/2019 03:23, Joseph Lo wrote:quoted
Hi Jon, Thanks for reviewing. On 1/24/19 6:30 PM, Jon Hunter wrote:quoted
On 07/01/2019 03:28, Joseph Lo wrote:quoted
The Tegra210 timer provides fourteen 29-bit timer counters and one 32-bit timestamp counter. The TMRs run at either a fixed 1 MHz clock rate derived from the oscillator clock (TMR0-TMR9) or directly at the oscillator clock (TMR10-TMR13). Each TMR can be programmed to generate one-shot periodic, or watchdog interrupts. Cc: Daniel Lezcano <redacted> Cc: Thomas Gleixner <redacted> Cc: linux-kernel@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Joseph Lo <redacted> --- .../bindings/timer/nvidia,tegra210-timer.txt | 25 +++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 Documentation/devicetree/bindings/timer/nvidia,tegra210-timer.txt diff --git a/Documentation/devicetree/bindings/timer/nvidia,tegra210-timer.txt b/Documentation/devicetree/bindings/timer/nvidia,tegra210-timer.txt new file mode 100644 index 000000000000..ba511220a669--- /dev/null +++ b/Documentation/devicetree/bindings/timer/nvidia,tegra210-timer.txt@@ -0,0 +1,25 @@ +NVIDIA Tegra210 timer + +The Tegra210 timer provides fourteen 29-bit timer counters and one32-bit +timestamp counter. The TMRs run at either a fixed 1 MHz clock rate derived +from the oscillator clock (TMR0-TMR9) or directly at the oscillator clock +(TMR10-TMR13). Each TMR can be programmed to generate one-shot, periodic, +or watchdog interrupts. + +Required properties: +- compatible : "nvidia,tegra210-timer". +- reg : Specifies base physical address and size of the registers. +- interrupts : A list of 4 interrupts; one per each of TMR10 through TMR13.
[snip]
quoted
And notice that only TMR10-TMR13 are running at the oscillator clock (clk_m). With the Tegra210 timer driver, we introduce in this series, which only replace the clock event device function that was originally owned by the arch timer (armv8 timer) and it also running at the oscillator clock. The sched_timer still owns by the arch timer. So the timer resolution will be the same. That's why we choose TMR10-TMR13 as the timer for Tegra210.That maybe fine, but DT should describe the hardware and so I don't see why we would not list all the interrupts. We can still only use TMR10-13 in the driver.
Okay, will list all the interrupts for each timer channel. Thanks, Joseph _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel