SK-AM64B: PCI Interface

Hi Debashis,

Thanks for your query.

I will check this internally and get back to you.

Best Regards

Ashwani

If your issue is development stage boot https://www.ti.com/tool/SK-AM64B I'd recommend modify the board as stated in the post you mentioned above https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1263036/sk-am64b-sd-card-not-boot-up/4785259 , or purchasing for example Sandisk SD cards which I've found typically to work fine on unmodified boards.

https://www.ti.com/tool/SK-AM64B does not support PCIe. You need to use https://www.ti.com/tool/TMDS64EVM to have a physical PCIe connector.

USB3 superspeed support is the reverse, https://www.ti.com/tool/SK-AM64B suports USB3.

  Pekka

Hi Pekka Varis,

We need to be able to boot up our custom board with PCIe and are looking for guidance to see if this is feasible. Can you please guide us to any resources that will help us evaluate this. Thank you.

Regards,

Debashis

We don't have PCIe boot examples in current SDKs. PCIe boot sequence is described in the TRM https://www.ti.com/lit/pdf/spruim2 in section 4.4.7.1 PCIe Bootloader Operation. You will have to write the R5 based bootloader to the address specified in the TRM.

We are looking to have an example in the MCU+ SDK 9.1 that should be released by December.

Have you already designed the board? I would recommend having a OSPI or another boot method available as well.

  Pekka

Thank you, Pekka. We are able to boot the system from OSPI. If we include OSPI and use it to just u-boot the board, is it possible to have kernel/dtb/rootfs from PCIe? If so, can you please share any documents/examples that do this?

We are still having issues with booting from SD card since the kernel/dtb/rootfs files are still on an SD card. We have tried multiple cards and it's repeatable on 2 boards (after updating the resistors as suggested in the other thread). The kernel/dtb/rootfs provided with the SDK is too large for us to flash in the OSPI (using this documentation Flash Linux to OSPI (ti.com)). We are working on reducing the size to only include the things we need for our board, but wanted another option is we are not able to reduce it more. In the meanwhile, can you also please point us to the location where we can download "tisdk-tiny-image-am64xx-evm.tar.xz" file (mentioned in the above linked tutorial).

Regards,

Debashis

I'm confused do you have your own HW design where you are having issues, or are you having issues with SK-AM64B?

If  SK-AM64B, please do the modifications as described on https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1263036/sk-am64b-sd-card-not-boot-up/4785259 to make SD Card boot consistent. There is no PCIe support on  SK-AM64B (no physical connectivity to PCIe of the SoC).

Or have you build a board with PCIe connector and OSPI flash?

Debashis Mahanty said:

In the meanwhile, can you also please point us to the location where we can download "tisdk-tiny-image-am64xx-evm.tar.xz" file (mentioned in the above linked tutorial).

Various different filesystems are available as prebuilt SD card images in directory /filesystem of the Linux SDK installation:

a0400797local@uda0400797:~$ ls ti-processor-sdk-linux-rt-am64xx-evm-08.06.00.42/filesystem/
data                                       tisdk-docker-rootfs-image-am64xx-evm.tar.xz
tisdk-base-image-am64xx-evm.tar.xz         tisdk-docker-rootfs-image-am64xx-evm.wic.bmap
tisdk-base-image-am64xx-evm.wic.bmap       tisdk-docker-rootfs-image-am64xx-evm.wic.xz
tisdk-base-image-am64xx-evm.wic.xz         tisdk-thinlinux-image-am64xx-evm.tar.xz
tisdk-bootstrap-image-am64xx-evm.tar.xz    tisdk-thinlinux-image-am64xx-evm.wic.bmap
tisdk-bootstrap-image-am64xx-evm.wic.bmap  tisdk-thinlinux-image-am64xx-evm.wic.xz
tisdk-bootstrap-image-am64xx-evm.wic.xz    tisdk-tiny-image-am64xx-evm.tar.xz
tisdk-default-image-am64xx-evm.tar.xz      tisdk-tiny-image-am64xx-evm.wic.bmap
tisdk-default-image-am64xx-evm.wic.bmap    tisdk-tiny-image-am64xx-evm.wic.xz
tisdk-default-image-am64xx-evm.wic.xz
a0400797local@uda0400797:~$

Hi Pekka,
Thank you for the images.
Till Now we are working on the Hardware side(carrier board) and we are currently testing SK-AM64B only.

Ok so the stabile way forward is fix the SD card as stated in https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1263036/sk-am64b-sd-card-not-boot-up/4785259 .

Hi Pekka,
We saw the EVM board(TMDS64EVM) schematics(Regarding SD card), we found the same circuit as in SKAM64B.
We are going to order the EVM board. So, if we can face any kind of issue regarding the sd card boot up. Can we proceed with the emmc interface as it mention 16Gb. So, can we put the complete rootfs(with kernel and dts everything) in that space and boot with out SD card.

           boot0 partition (7 MB)                        user partition
   0x0+----------------------------------+      0x0+-------------------------+
      |     tiboot3.bin (512 KB)         |         |                         |
 0x400+----------------------------------+         |                         |
      |       tispl.bin (2 MB)           |         |                         |
0x1400+----------------------------------+         |        rootfs           |
      |       u-boot.img (4 MB)          |         |                         |
0x3400+----------------------------------+         |                         |
      |      environment (128 KB)        |         |                         |
0x3500+----------------------------------+         |                         |
      |   backup environment (128 KB)    |         |                         |
0x3600+----------------------------------+         +-------------------------+

Regards
Debashis