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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Good day Mathieu,

On 1/24/2019 9:37 PM, Mathieu Poirier wrote:
Good day Sai,

On Wed, 23 Jan 2019 at 13:18, Sai Prakash Ranjan
<saiprakash.ranjan@xxxxxxxxxxxxxx> wrote:

Hi Mathieu,

On 1/24/2019 12:44 AM, Mathieu Poirier wrote:
On Wed, 23 Jan 2019 at 05:12, Sai Prakash Ranjan
<saiprakash.ranjan@xxxxxxxxxxxxxx> wrote:

That depends on whether the ETMs have been modified at all, something
Suzuki has asked to be clarified.  If ETMs have been modified then we
need to understand how they differ from the driver's implementation.

We had asked hardware team for clarification regarding this. Let me
poke them again. As for the driver, downstream implementation also
uses the same driver, so I am not sure what do you mean by differing
from the driver's implementation.

The driver has been implemented in accordance to ARM's coresight
technical reference manual and expects the HW to behave in accordance
to that specification.  Here we want to make sure the IP on your board
is conformant to the same specification.  If not then the driver needs
to be made flexible to handle both kind IPs.


The HW does behave as per the specification. As discussed in reply to
Suzuki, Coresight peripherals do use JEP106 ID of ARM for SDM845 and for MSM8996, the ID is of QCOM(0x70) since it was not based on any ARM derivative.
And the etm4x driver handles it all well. Other values of PID registers
are implementation defined and can be different from standard ARM cpu
core types.

Thanks,
Sai

--
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux