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braswell pcie training

sbass
Beginner
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i have FPGA device pcie, but i load fpga after enumeration pcie, how to configure braswell for support pcie hot-plug ? or re-launch training pcie ?

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CarlosAM_INTEL
Moderator
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Hello, keziaha:

Thank you for contacting Intel Embedded Community.

In order to implement PCIe hot-plug please use the Slot Capabilities (SLCAP) register specifically the Hot-Plug Capable (HPC) and Hot-Plug Surprise (HPS) bits; and Slot Control; Slot Status (SLCTL_SLSTS) register specifically the Hot-Plug Interrupt Enable (HPE) bit. This information and more details are stated in sections 36.1.18 and 36.1.19; on pages 2421 and 2423 of the https://www-ssl.intel.com/content/www/us/en/secure/embedded/nda/products/braswell/n-series-pentium-celeron-processors-eds-vol-3.html N-series Intel® Pentium® Processors and Intel® Celeron® Processors External Design Specification (EDS) – Volume 3 of 3 document # 547871.

We hope that this information may help you.

Best regards,

Carlos_A.

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CarlosAM_INTEL
Moderator
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Hello, keziaha:

Thank you for contacting Intel Embedded Community.

In order to implement PCIe hot-plug please use the Slot Capabilities (SLCAP) register specifically the Hot-Plug Capable (HPC) and Hot-Plug Surprise (HPS) bits; and Slot Control; Slot Status (SLCTL_SLSTS) register specifically the Hot-Plug Interrupt Enable (HPE) bit. This information and more details are stated in sections 36.1.18 and 36.1.19; on pages 2421 and 2423 of the https://www-ssl.intel.com/content/www/us/en/secure/embedded/nda/products/braswell/n-series-pentium-celeron-processors-eds-vol-3.html N-series Intel® Pentium® Processors and Intel® Celeron® Processors External Design Specification (EDS) – Volume 3 of 3 document # 547871.

We hope that this information may help you.

Best regards,

Carlos_A.

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sbass
Beginner
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Hello, Thank you for response, I can't see device pci, which register for debug training pcie ? the fpga device pci is blocked in compliance state.

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CarlosAM_INTEL
Moderator
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Hello, keziaha:

In order to be on the same page, could you please give us all the information of the FPGA?

Could you please tell us if you have contacted the FPGA manufacturer to consult about this situation? In case that your answer is positive, please give us all the communication that they provided to you.

Could you please let us know the documents that you have used to implement the Braswell design? By the way, it has been reviewed by Intel?

Could you please give us a block diagram of the affected design?

We really appreciate your help to solve this inconvenience, so please give us all the information that should answer these questions.

Best regards,

Carlos_A.

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CarlosAM_INTEL
Moderator
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Hello, keziaha :

Thanks for your reply.

In order to set PCIe training, please use the Link Control; Link Status (LCTL_LSTS) Register specifically the Link Bandwidth Management Status (LBMS), Link Training (LT), and Retrain Link (RL) bits.This information and more details are stated in sections 36.1.17; on pages 2418, 2419 and 2420 of the https://www-ssl.intel.com/content/www/us/en/secure/embedded/nda/products/braswell/n-series-pentium-celeron-processors-eds-vol-3.html N-series Intel® Pentium® Processors and Intel® Celeron® Processors External Design Specification (EDS) – Volume 3 of 3 document # 547871.

We hope that this information may help you.

Best regards,

Carlos_A.

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sbass
Beginner
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Hello Carlos,

we check with fpga team several point before you disturb.

Best regards,

Sébastien

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sbass
Beginner
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We have configured port 1 in hotplug, we haven't no detection, we check with oscilloscope on data pci, no signal of detection.

In hotplug mode, can you explain pci detection ? can you force pci detection?

As a reminder, we load fpga(altera cyclone V)after enumeration PCI to do by coreboot. I would like use hot plug detection for see fpga device.

Best regards,

Sébastien

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CarlosAM_INTEL
Moderator
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Hello, keziaha:

Thanks for your replies.

Based on your previous communications, could you answer our communication of the past April 21st, 2017 8:13 AM?

Waiting for your answers.

Best regards,

Carlos_A.

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sbass
Beginner
1,076 Views

In response to the mail past April 21st, 2017 8:13 AM:

1.I don't have contact with FPGA manufacturer. FPGA is cyclone V with IP standard for pcie.

2.our design has been reviewed by Intel.

3.For block diagram, i can provide directly, but not through the forum, how to send directly ?

Sébastien

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sbass
Beginner
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Hello Carlos,

when i set LCTL_LSTS RL bit, i have Link Training (LT) change value to 1 , but when i check to oscilloscope on data line, i don't have signal , no detection, why ?

After LT set : i check in loop:

LCTL_LSTS LT : always 1

PCIESTS1 LTSMSTATE : always 1

LCTL_LSTS LBMS : always 0

best regards,

Sébastien

SLCAP

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CarlosAM_INTEL
Moderator
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Hello, keziaha:

Thanks for your reply.

Based on your previous communication, we would like to address the following questions:

Could you please clarify if this problem is related to a specific PCIe port or various? In case that you ignore the answer, please try to reproduce this situation on different PCIe ports and let us know the results.

Could you please tell us if the affected PCIe ports have issues with other PCIe cards?

Could you please let us know the procedure that you have followed to check your Braswell design with the help of Intel? By the way, where do you find the steps to perform this verification?

Could you please verify the FPGA implementation with its manufacturer help and let us know the results?

Please let us know the information that should answer these consultations to have a better idea of this issue.

Waiting for your reply.

Best regards,

Carlos_A.

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sbass
Beginner
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Hello,

In datasheet " 18.2.2.1 Express Card Hot-Plug Events":

A full Hot-plug Controller is not implemented.

Presence detection occurs when a PCI Express* device is plugged in and power is

supplied. The physical layer will detect the presence of the device, and the root port will

set the SLSTS.PDS and SLSTS.PDC bits.

if only :

SLCAP --> Hot-Plug Capable (HPC) & Hot-Plug Surprise (HPS) is set.

SLCTL_SLSTS --> Hot-Plug Interrupt Enable (HPE) & Presence Detect Changed Enable (PDE) is set

SLSTS.PDS and SLSTS.PDC is set when detection ?

But training pcie is executed while detection or we must launch manually training ?

In my case, i have fpga already connected, but not loaded with firmware. i can use hot plug detection, when fpga loaded ?

i tested:

set CLIST_XCAP.SI = 1

1/ check before load fpga slsts.pds & slsts.pdc == 1

2/ load fpga

3/ check after , slsts.pds & slsts.pdc == 1

Why before load fpga pds = 1 ? how to working detection ?

Best Regards

Sébastien

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sbass
Beginner
1,076 Views

Hello, here my answer:

Based on your previous communication, we would like to address the following questions:

Could you please clarify if this problem is related to a specific PCIe port or various? In case that you ignore the answer, please try to reproduce this situation on different PCIe ports and let us know the results.

A---> FPGA is plugged on first pci device port, Port1.We have design an card with braswell & fpga on same PCB. We have other device pci, there is no problem with other device.

Could you please tell us if the affected PCIe ports have issues with other PCIe cards?

A---> We have other device pci, there is no problem with other device.

Could you please let us know the procedure that you have followed to check your Braswell design with the help of Intel? By the way, where do you find the steps to perform this verification?

A---> i don't have all information, but we have provided electrical diagram for perform verification.

Could you please verify the FPGA implementation with its manufacturer help and let us know the results?

A---> we have team fpga internal, with a lot of experience.

Please let us know the information that should answer these consultations to have a better idea of this issue.

Normally, in generic PC, the device PCI is ready before cpu, when we boot. In our case,

our pci device (fpga) is not ready when we boot.Because there isn't firmware in FPGA.

So, when the cpu launch detection , the fpga device not responding.

For resolve this issue, after loading of firmware in fpga, i have 2 solutions:

- hot-plug feature: the detection pci is automatically launch by cpu after loading firmware fpga.

For the moment, this way is not working, see message : sebastien basset Apr 28, 2017 5:32 AM

- Another solution: re-launch detection manually, see message : April 26, 2017, 10:21 AM.

For resume, i need to know how to relaunch detection PCI ?

Best Regards,

Sébastien Basset

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CarlosAM_INTEL
Moderator
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Hello, keziaha:

Thanks for your update that we really appreciate.

Based on your previous communication and since Intel guarantees the proper functionality, such fulfilling the standards listed as supported, of their devices if your design achieves with the suggestion listed in their documentation, the problem with PCIe ports only happens with the FPGA implementation as you mentioned, so it is totally related to the FPGA design.

Due to this fact, we suggest you as a reference use the support channel that better fit to your needs of the listed at the FPGA manufacturer https://www.altera.com/support.html Support website.

We hope that this information is useful to you.

Best regards,

Carlos_A .

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