Re: [PATCH v3 1/1] dt-bindings: timer: Add new OST support for the upcoming new driver.

[Rob Herring <robh@kernel.org>]

On Mon, 26 Oct 2020 23:58:42 +0800, 周琰杰 (Zhou Yanjie) wrote:
> The new OST has one global timer and two or four percpu timers, so there
> will be three combinations in the upcoming new OST driver: the original
> GLOBAL_TIMER + PERCPU_TIMER, the new GLOBAL_TIMER + PERCPU_TIMER0/1 and
> GLOBAL_TIMER + PERCPU_TIMER0/1/2/3, For this, add the macro definition
> about OST_CLK_PERCPU_TIMER0/1/2/3. And in order to ensure that all the
> combinations work normally, the original ABI values of OST_CLK_PERCPU_TIMER
> and OST_CLK_GLOBAL_TIMER need to be exchanged to ensure that in any
> combinations, the clock can be registered (by calling clk_hw_register())
> from index 0.
> 
> Before this patch, OST_CLK_PERCPU_TIMER and OST_CLK_GLOBAL_TIMER are only
> used in two places, one is when using "assigned-clocks" to configure the
> clocks in the DTS file; the other is when registering the clocks in the
> sysost driver. When the values of these two ABIs are exchanged, the ABI
> value used by sysost driver when registering the clock, and the ABI value
> used by DTS when configuring the clock using "assigned-clocks" will also
> change accordingly. Therefore, there is no situation that causes the wrong
> clock to the configured. Therefore, exchanging ABI values will not cause
> errors in the existing codes when registering and configuring the clocks.
> 
> Currently, in the mainline, only X1000 and X1830 are using sysost driver,
> and the upcoming X2000 will also use sysost driver. This patch has been
> tested on all three SoCs and all works fine.
> 
> Tested-by: 周正 (Zhou Zheng) <sernia.zhou@foxmail.com>
> Signed-off-by: 周琰杰 (Zhou Yanjie) <zhouyanjie@wanyeetech.com>
> ---
> 
> Notes:
>     v1->v2:
>     Rewrite the commit message so that each line is less than 80 characters.
> 
>     v2->v3:
>     Add the description of why the exchange of ABI values will not affect
>     the existing driver into the commit message.
> 
>  include/dt-bindings/clock/ingenic,sysost.h | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 

Reviewed-by: Rob Herring <robh@kernel.org>