topic Re: How to implement DMA controller in PCIe root complex(RC) mode? in i.MX Processors

How to implement DMA controller in PCIe root complex(RC) mode?

mimi05633 — Thu, 27 May 2021 09:26:04 GMT

Hi NXP team,

In the IMX8MDQLQ reference manual, I can see PCIe has an embedded DMA.
How to implement DMA controller in PCIe root complex(RC) mode? And does any kernel config need to enable?

Topology: IMX8MQ(RC) ---(mini-pcie)--- FPGA(EP)

My harware:
- IMX8MQ customize board (software: LF_L5.4.3_1.0.0)

I appreciate if someone can help me to solve it.

Thank you for any help.
Minying

Re: How to implement DMA controller in PCIe root complex(RC) mode?

igorpadykov — Thu, 27 May 2021 11:47:41 GMT

Hi Minying

one can look at pcie driver :

https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/pci/controller/dwc/pci-imx6.c?h=imx_5.4.3_2.0.0

Best regards
igor

Re: How to implement DMA controller in PCIe root complex(RC) mode?

mimi05633 — Thu, 27 May 2021 13:43:15 GMT

Hi Igor,
Thank you for your reply.
In the pci_imx6.c, there is a self io test by dma in EP mode. Can it also be used in RC mode?
If yes, can the self io test be used after PCIe links up? Is there a need to do other initial setups before the self io test?

Best regards,
minying