Using the signature unit on the A35

[hbabar]

Hello,

I am using a i.MX8QXP processor. I am trying to write a driver for the Linux OS running on the A35 quadcore that when called triggers the crc checksum generation for the displayed image(s). I am using the functionality offered by the dpu signature module ( dpu-signature.c in /drivers/gpu/imx/dpu/ ).

However almost all the functions in dpu-signature.c require a pointer to a valid struct dpu_signature object which can be obtained from:

struct dpu_signature *dpu_sig_get(struct dpu_soc *dpu, int id)

 which in turn requires a pointer to a valid struct dpu_soc object. How do I obtain a pointer to this ?

I am quite new at this so any extra details / pointers (see what I did eh ?) would be appreciated.

[hbabar]

Hi,

For that I would need to get a pointer to a valid struct dpu_crtc object. How would I do that ?

Regards

[hbabar]

Hello,

it has been sometime. Do you have any updates ?

[Bio_TICFSL]

Hello hbbar,

The i.MX8QX does not have A35, neither have DPU, I think your though goes to A53 but the QXP don't have dpu. please clarify.

Regards

[hbabar]

Hello Bio_TICFSL,

the i.MX8QXP does contain A35 and M4 sub cores. Please refer to the attached Processor Reference Manual and the output of lscpu.

root@imx8qxpsthu:~# lscpu
Architecture: aarch64
Byte Order: Little Endian
CPU(s): 4
On-line CPU(s) list: 0-3
Thread(s) per core: 1
Core(s) per socket: 4
Socket(s): 1
Vendor ID: ARM
Model: 2
Model name: Cortex-A35
Stepping: r0p2
CPU max MHz: 1200.0000
CPU min MHz: 900.0000
BogoMIPS: 16.00
L1d cache: unknown size
L1i cache: unknown size
L2 cache: unknown size
Flags: fp asimd evtstrm aes pmull sha1 sha2 crc32 cpuid

Regards

[Bio_TICFSL]

Hi,

Yes, you are right A35 works on QXP and not on QX. Will Check your issue.

[hbabar]

Any updates ?

[Bio_TICFSL]

Hi,

Can you try to use dev_get_drvdata() to get the struct dpu_soc *dpu object?

sample code is in function of "dpu_crtc_get_resources(struct dpu_crtc *dpu_crtc)"

Regards