[PATCH 2/4] clk: renesas: r8a73a4: Implement ZT/ZTR trace clock on R-Mobile APE6

Marek Vasut marek.vasut at mailbox.org
Wed May 13 06:37:10 PDT 2026


On 5/13/26 3:15 PM, Geert Uytterhoeven wrote:

Hello Geert,

> On Sat, 2 May 2026 at 20:56, Marek Vasut
> <marek.vasut+renesas at mailbox.org> wrote:
>> Implement ZT trace bus and ZTR trace clock on the R-Mobile APE6.
>>
>> Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
> 
> Thanks for your patch!
> 
> /sys/kernel/debug/clk/clk_summary looks a bit off to me:
> 
>      zt                         0       0        0        208000000
>      ztr                        0       0        0        277333334
> 
>> --- a/drivers/clk/renesas/clk-r8a73a4.c
>> +++ b/drivers/clk/renesas/clk-r8a73a4.c
>> @@ -43,6 +43,8 @@ static struct div4_clk div4_clks[] = {
>>          { "m1", CPG_FRQCRA,  4 },
>>          { "m2", CPG_FRQCRA,  0 },
>>          { "zx", CPG_FRQCRB, 12 },
>> +       { "ztr", CPG_FRQCRB, 16 },
> 
> 20?
> 
>> +       { "zt", CPG_FRQCRB, 12 },
> 
> 16? (12 is zx, cfr. above).
> 
> I.e. the same shifts as on R-Mobile A1.
> 
>>          { "zs", CPG_FRQCRB,  8 },
>>          { "hp", CPG_FRQCRB,  4 },
>>          { NULL, 0, 0 },
> 
> After fixing the shifts, I get:
> 
>      zt                         0       0        0        277333334
>      ztr                        0       0        0        277333334
> 
> which looks much better. If you agree, I can fix this while applying.

Yes please. I can confirm in APE6 RM v0.7 that the ZTFC is at bit offset 
16 and ZTRFC at bit offset 20 . Thank you for spotting this.

-- 
Best regards,
Marek Vasut



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