Re: [PATCHv4 1/4] arm64: dts: qcom: sdm845: Add Coresight support

[Suzuki K Poulose <suzuki.poulose@arm.com>]

Hi Sai,

On 23/01/2019 12:11, Sai Prakash Ranjan wrote:
> Hi Suzuki,
> 
> On 1/23/2019 1:42 AM, Suzuki K Poulose wrote:
>> Hi Sai,
>>
>> On 01/22/2019 04:48 PM, Sai Prakash Ranjan wrote:
>>> Hi Suzuki,
>>>
> [..]
>>>
>>> SDM845 has 4 Kryo 385 Gold (ARM A75) + 4 Kryo 385 Silver (ARM A55),
>>> so the PID values should be same for 4 ETMs atleast. But here one
>>> pid value(001bb803) is same for 6 ETMs and other one for 2
>>> ETMs(001bb802) which seems odd and hence the doubt if these pids
>>> are even valid ones.
>>
>> Have you checked other SoCs with A55 for the ETM PID ? The drivers
>> usually only care about PID0[7-0], PID1[7-0], PID2[3-0] and ignores
>> the other fields that may change over revisions of the core. So, in your
>> case the ETM ID could be treated as 0xbb802 and 0xbb803.
>>
> 
> Very sorry to have mislead you here. I checked again today on SDM845 and
> as you said 4 ETMs based on A75 has 0xbb803 and other 4 ETMs based on
> A55 has 0Xbb803. I wrongly mentioned it as 6 and 2.
> 
> [    6.688809] resname=etm@7040000 pid = 0x1bb803
> [    6.694957]
> [    6.694957] resname=etm@7140000 pid = 0x1bb803
> [    6.701135]
> [    6.701135] resname=etm@7240000 pid = 0x1bb803
> [    6.707256]
> [    6.707256] resname=etm@7340000 pid = 0x1bb803
> [    6.713454]
> [    6.713454] resname=etm@7440000 pid = 0x1bb802
> [    6.719621]
> [    6.719621] resname=etm@7540000 pid = 0x1bb802
> [    6.725814]
> [    6.725814] resname=etm@7640000 pid = 0x1bb802
> [    6.731971]
> [    6.731971] resname=etm@7740000 pid = 0x1bb802
> 
> So is it ok to add these to table as below in etm4x driver with the
> following comment since these do not exactly match A75 and A55 PIDs
> which you provided? Or any other way you prefer?
> 
> @@ -1079,6 +1079,10 @@ static const struct amba_id etm4_ids[] = {
>           ETM4x_AMBA_ID(0x000bb95a),              /* Cortex-A72 */
>           ETM4x_AMBA_ID(0x000bb959),              /* Cortex-A73 */
>           ETM4x_AMBA_ID(0x000bb9da),              /* Cortex-A35 */
> +       ETM4x_AMBA_ID(0x000f0211),              /* Qualcomm Kryo */
> +       ETM4x_AMBA_ID(0x000f0205),              /* Qualcomm Kryo */
> +       ETM4x_AMBA_ID(0x000bb803),              /* Qualcomm Kryo 385
> Cortex-A75 */
> +       ETM4x_AMBA_ID(0x000bb802),              /* Qualcomm Kryo 385
> Cortex-A55 */
>           {},

That looks fine with me. But as Mathieu said, this needs to be a separate
patch. But before all that please could you provide me the PIDR4 value for
the Kryo A75 and A55 please ?

Kind regards
Suzuki