topic PCIe Mini linkup fail issue in i.MX Processors

PCIe Mini linkup fail issue

zhaocq — Mon, 03 Dec 2018 08:44:21 GMT

Dear NXP,

Under linux Linux version 3.0.35_B01_V1.0, a imx6q-like board is connected to a PCIE-mini interface wlan RTL8192EE. Checked the differential clock is about 100MHz, the power and reset is supplied. Pcie has been configurated like that:

[    6.457696] iMX6 PCIe PCIe RC mode imx_pcie_pltfm_probe entering.
[    6.464063] _clk_pcie_enable!!
[    6.467207] PCIE: imx_pcie_pltfm_probe card_reset.
[    6.578918] PCIE: imx_pcie_pltfm_probe start link up.
[    6.584062] PCIE: imx_pcie_pltfm_probe add_pcie_port.
[    7.195101] link up failed, DB_R0:0x00ea5800, DB_R1:0x08200000!
[    7.201138] IMX PCIe port: link down with power supply 1!

I tested the PCIE_TXP/PCIE_TXN pin signal waveform, as the attached file pcie.jpg. The amplitude peak is 400mV.

Is this waveform correct ?Could you give us some advise about this issue?

Best Regards!

cuiqin

Re: PCIe Mini linkup fail issue

igorpadykov — Tue, 04 Dec 2018 02:55:13 GMT

Hi cuiqin

Linux version 3.0.35 is very old version and since then very much improvements

were implemented in pcie driver, one can try latest Linux L4.9.88 pcie driver

which is working fine: linux/drivers/pci/host/pci-imx6.c and port changes to old version:

pci-imx6.c\host\pci\drivers - linux-imx - i.MX Linux kernel

Best regards
igor
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Re: PCIe Mini linkup fail issue

zhaocq — Wed, 05 Dec 2018 09:42:19 GMT

Hi igor,

Thanks for your reply first.

I have updated to later Linux version 4.1.15, just add the pci config to imx_v7_android_defconfig.
on the load stage, i use dmesg grep pcie ,also can see the below info:

130|root@sabresd_6dq:/ # dmesg |grep -rin "pci"
(standard input):80:[    0.186674] !!request miniPCIE Power On gpio
(standard input):89:[    0.234583] MPCIE_3V3: Failed to request enable GPIO83: -16
(standard input):133:[    0.368953] PCI: CLS 0 bytes, default 64
(standard input):214:[    3.313536] ehci-pci: EHCI PCI platform driver
(standard input):359:[    5.483263] imx6q-pcie 1ffc000.pcie: phy link never came up
(standard input):360:[    5.488878] imx6q-pcie 1ffc000.pcie: DEBUG_R0: 0x0c454504, DEBUG_R1: 0x1800f700
(standard input):361:[    5.496216] imx6q-pcie 1ffc000.pcie: failed to initialize host
(standard input):362:[    5.502100] imx6q-pcie: probe of 1ffc000.pcie failed with error -22

Please give me some advise on this issue, any help is appreciated !

Best regards

cuiqin

Re: PCIe Mini linkup fail issue

igorpadykov — Wed, 05 Dec 2018 10:35:19 GMT

Hi cuiqin

please try with Demo Image

https://www.nxp.com/webapp/Download?colCode=L4.1.15_2.0.0_MX6QDLSOLO&appType=license&location=null&Parent_nodeId=1337699…

Best regards
igor