On Thu, Sep 3, 2020 at 4:23 PM Sean Anderson seanga2@gmail.com wrote:
On 9/3/20 1:01 AM, Anup Patel wrote:
On Thu, Sep 3, 2020 at 8:19 AM Bin Meng bmeng.cn@gmail.com wrote:
Hi Anup,
On Thu, Sep 3, 2020 at 10:46 AM Anup Patel anup@brainfault.org wrote:
On Thu, Sep 3, 2020 at 7:32 AM Bin Meng bmeng.cn@gmail.com wrote:
Hi Anup,
On Tue, Aug 18, 2020 at 6:03 PM Sean Anderson seanga2@gmail.com wrote:
On 8/18/20 5:22 AM, Bin Meng wrote: > +Anup Patel > > On Wed, Jul 29, 2020 at 5:57 PM Sean Anderson seanga2@gmail.com wrote: >> >> We may need to add a clock-frequency binding like for the K210. >> >> Signed-off-by: Sean Anderson seanga2@gmail.com >> --- >> This patch builds but has NOT been tested. >> >> Changes in v2: >> - Fix SiFive CLINT not getting tick-rate from rtcclk >> >> arch/riscv/dts/fu540-c000-u-boot.dtsi | 8 ++++++-- >> arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi | 4 ++++ >> 2 files changed, 10 insertions(+), 2 deletions(-) >> >> diff --git a/arch/riscv/dts/fu540-c000-u-boot.dtsi b/arch/riscv/dts/fu540-c000-u-boot.dtsi >> index afdb4f4402..f126d3e0b3 100644 >> --- a/arch/riscv/dts/fu540-c000-u-boot.dtsi >> +++ b/arch/riscv/dts/fu540-c000-u-boot.dtsi >> @@ -53,9 +53,13 @@ >> reg = <0x0 0x10070000 0x0 0x1000>; >> fuse-count = <0x1000>; >> }; >> - clint@2000000 { >> + clint: clint@2000000 { >> compatible = "riscv,clint0"; >> - interrupts-extended = <&cpu0_intc 3 &cpu0_intc 7 &cpu1_intc 3 &cpu1_intc 7 &cpu2_intc 3 &cpu2_intc 7 &cpu3_intc 3 &cpu3_intc 7 &cpu4_intc 3 &cpu4_intc 7>; >> + interrupts-extended = <&cpu0_intc 3 &cpu0_intc 7 >> + &cpu1_intc 3 &cpu1_intc 7 >> + &cpu2_intc 3 &cpu2_intc 7 >> + &cpu3_intc 3 &cpu3_intc 7 >> + &cpu4_intc 3 &cpu4_intc 7>; >> reg = <0x0 0x2000000 0x0 0xc0000>; >> u-boot,dm-spl; >> }; >> diff --git a/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi b/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi >> index e037150520..3275bb1f12 100644 >> --- a/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi >> +++ b/arch/riscv/dts/hifive-unleashed-a00-u-boot.dtsi >> @@ -26,6 +26,10 @@ >> >> }; >> >> +&clint { >> + clocks = <&rtcclk>; >> +}; > > Can we consider making this property a standard property by the kernel > upstream? How does the kernel CLINT timer driver determine its running > frequency?
Currently it gets it from /cpus/timebase-frequency.
What's your comment on this? I think this should go upstream to the standard bindings.
My apologies for delay. Too many mailing list to track.
I think "clocks" should be an optional DT property for CLINT driver (both Linux and U-Boot). If "clocks" is not available then we should fallback to "/cpus/timebase-frequency"
Agreed. The question is whether this should be mentioned in the DT bindings doc in the kernel tree?
Yes, the "clocks" DT property should be updated in kernel DT bindings doc and kernel CLINT driver should also prefer "clocks" DT property when available.
Regards, Anup
Should clock-frequency be used as well, or should that be left for timebase-frequency?
Not sure about clock-frequency DT property. I think very few linux clocksource drivers use "clock-frequency" DT property.
Probably it's fine to first check for "clocks" and "clock-frequency" before falling back to "timebase-frequency".
Regards, Anup
--Sean