Re: [PATCH 02/13] dt-bindings: clock: google,gs101-clock: add PERIC0 clock management unit

From: Tudor Ambarus
Date: Thu Dec 28 2023 - 02:50:07 EST




On 12/28/23 07:30, Krzysztof Kozlowski wrote:
> On 27/12/2023 13:38, Tudor Ambarus wrote:
>> Hi, Rob,
>>
>> On 12/21/23 07:20, Tudor Ambarus wrote:
>>>
>>>
>>> On 12/20/23 15:07, Rob Herring wrote:
>>>> On Thu, Dec 14, 2023 at 10:52:32AM +0000, Tudor Ambarus wrote:
>>>>> Add dt-schema documentation for the Connectivity Peripheral 0 (PERIC0)
>>>>> clock management unit.
>>>>>
>>>>> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
>>>>> ---
>>>>> .../bindings/clock/google,gs101-clock.yaml | 25 +++++-
>>>>> include/dt-bindings/clock/google,gs101.h | 86 +++++++++++++++++++
>>>>> 2 files changed, 109 insertions(+), 2 deletions(-)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml b/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
>>>>> index 3eebc03a309b..ba54c13c55bc 100644
>>>>> --- a/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
>>>>> +++ b/Documentation/devicetree/bindings/clock/google,gs101-clock.yaml
>>>>> @@ -30,14 +30,15 @@ properties:
>>>>> - google,gs101-cmu-top
>>>>> - google,gs101-cmu-apm
>>>>> - google,gs101-cmu-misc
>>>>> + - google,gs101-cmu-peric0
>>>>>
>>>>> clocks:
>>>>> minItems: 1
>>>>> - maxItems: 2
>>>>> + maxItems: 3
>>>>>
>>>>> clock-names:
>>>>> minItems: 1
>>>>> - maxItems: 2
>>>>> + maxItems: 3
>>>>>
>>>>> "#clock-cells":
>>>>> const: 1
>>>>> @@ -88,6 +89,26 @@ allOf:
>>>>> - const: dout_cmu_misc_bus
>>>>> - const: dout_cmu_misc_sss
>>>>>
>>>>> + - if:
>>>>> + properties:
>>>>> + compatible:
>>>>> + contains:
>>>>> + const: google,gs101-cmu-peric0
>>>>> +
>>>>> + then:
>>>>> + properties:
>>>>> + clocks:
>>>>> + items:
>>>>> + - description: External reference clock (24.576 MHz)
>>>>> + - description: Connectivity Peripheral 0 bus clock (from CMU_TOP)
>>>>> + - description: Connectivity Peripheral 0 IP clock (from CMU_TOP)
>>>>> +
>>>>> + clock-names:
>>>>> + items:
>>>>> + - const: oscclk
>>>>> + - const: dout_cmu_peric0_bus
>>>>> + - const: dout_cmu_peric0_ip
>>>>
>>>> 'bus' and 'ip' are sufficient because naming is local to the module. The
>>>> same is true on 'dout_cmu_misc_bus'. As that has not made a release,
>>>> please fix all of them.
>>>>
>>>
>>> Ok, will fix them shortly. Thanks, Rob!
>>
>> I tried your suggestion at
>> https://lore.kernel.org/linux-arm-kernel/c6cc6e74-6c3d-439b-8dc1-bc50a88a3d8f@xxxxxxxxxx/
>>
>> and we noticed that we'd have to update the clock driver as well.
>> These CMUs set the DT clock-name of the parent clock in the driver in
>> struct samsung_cmu_info::clk_name[]. The driver then tries to enable the
>> parent clock based on the clock-name in exynos_arm64_register_cmu().
>>
>> In order to enable the parent clock of the CMU the following would be
>> needed in the driver:
>>
>> diff --git a/drivers/clk/samsung/clk-gs101.c
>> b/drivers/clk/samsung/clk-gs101.c
>> index 68a27b78b00b..e91836ea3a98 100644
>> --- a/drivers/clk/samsung/clk-gs101.c
>> +++ b/drivers/clk/samsung/clk-gs101.c
>> @@ -2476,7 +2476,7 @@ static const struct samsung_cmu_info misc_cmu_info
>> __initconst = {
>> .nr_clk_ids = CLKS_NR_MISC,
>> .clk_regs = misc_clk_regs,
>> .nr_clk_regs = ARRAY_SIZE(misc_clk_regs),
>> - .clk_name = "dout_cmu_misc_bus",
>> + .clk_name = "bus",
>
> Yes, obviously, the names are used...
>
> The entire point was that a week ago Rob said:
> "As that has not made a release, please fix all of them."
> but if you keep waiting, like 8 days for this simple patch, his
> statement is not true anymore.
>

I saw the problem at the end of Thursday, reported it, and after that I
entered vacation.

> The only point was to send a fix *the next day*, so I would apply it and
> send further. You kind of solved that problem by waiting entire week for
> a simple driver and DTS change.
>
Why can't we queue the name fix as a patch for v6.8-rc1? Of course if
you consider that the change is worth it. As I said, I lean towards not
changing it.

Thanks,
ta