topic Re: PCIe reset for T1042 in PowerQUICC Processors

PCIe reset for T1042

utkarsh_100 — Wed, 11 Sep 2019 04:24:20 GMT

Hi All

I am referring QorIQ T1040 Reference Manual for my board T1042 where I want to reset the only pcie . But I could not able to find out how to reset the pcie .

Then I referred QorIQ T1040 Reference Design Board User Guide where I found out CPLD under that RSTCON2 register from which I can reset the PCIe

After memory mapping for the for RSTCON2 register on my vxworks platform I tried to write 1 to clear for resetting the PCIe , but not sure whether it got reset or not .

When I read default value RSTCON2 it was 0xFF ,but after writing also on pcie bit its still 0xFF . (no change)

I have few question related to my comments

1. How can I know CPLD is present on my target board T1042 since in refernce manual I could not find out anything related to that.

2.Is there any other way I can reset only pcie interface .

Thanks in advance

Re: PCIe reset for T1042

shaneggpierce — Wed, 11 Sep 2019 18:15:39 GMT

utkarsh_100 wrote:
Hi All
I am referring QorIQ T1040 Reference Manual for my board T1042 where I want to reset the only pcie . But I could not able to find out how to reset the pcie .
Then I referred QorIQ T1040 Reference Design Board User Guide where I found out CPLD under that RSTCON2 register from which I can reset the PCIe
After memory mapping for the for RSTCON2 freejobalert gimp notepad++ register on my vxworks platform I tried to write 1 to clear for resetting the PCIe , but not sure whether it got reset or not .
When I read default value RSTCON2 it was 0xFF ,but after writing also on pcie bit its still 0xFF . (no change)

I have few question related to my comments

1. How can I know CPLD is present on my target board T1042 since in refernce manual I could not find out anything related to that.

2.Is there any other way I can reset only pcie interface .

Thanks in advance

I also have similar questions. Help is appreciated.

Thanks in advance.
Regards

Shane

Re: PCIe reset for T1042

Bulat — Thu, 12 Sep 2019 12:00:16 GMT

You seem to mix up different reset terms. The only way to reset PCI Express interface of the processor is to reset the processor using PORESET or HRESET.

T1040 Reference Design Board (T1040RDB, T1042RDB) contains three PCIe connectors, two Mini PCIe and one PCIe x1 slot. The board has a feature allowing to assert reset signals going to each of these connectors, this is realised via on-board CPLD. RSTCON2 register located in the CPLD controls those reset signals, so the user is able to assert reset individually for each slot in software. You have to understand that the CPLD is an external device to the T1040/T1042, not the part of the processor. That is why it is not described in the QorIQ T1040 Reference Manual.

Regards,

Bulat