Jetson Linux 34.1 Kernel 5.10 - SDIO bus failure on Xavier NX

Hi all,

I am using BCM43455 broadcom wifi on a SDIO bus ‘sdhci@3440000’.
As discussed in the below topic, we were able to get WiFi working on Jetson linux 32.x versions.

Trying to port the same on Jetpack 34.1 version. The device tree entries are same as earlier. Observed that the gpio - TEGRA194_AON_GPIO(CC, 4) which we are using as ‘wlan-output-high’ was being used for pwm_fan_shared_data. Disabled this node to avoid complications so the GPIO will be used for WiFi. But this did not help. We are using built-in broadcom wifi drivers and building them as module. I am getting no prints from the respective wifi driver.

I am able to see the below log,
sdhci-tegra 3440000.sdhci: BWMGR client registration for eMC Successful.
But, mmc1: new ultra high speed SDR104 SDIO card at address 0001 is not seen.

Later we found out that SDIO bus itself is not up. On further debugging on the mmc SDIO driver, we found that ‘mmc_attach_sdio’ is not happening in ‘drivers/mmc/core/sdio.c’. It is failing here,
err = mmc_send_io_op_cond(host, 0, &ocr);
Attached debug log for reference.

dmesg.txt (134.7 KB) (additional debug prints are added)


Sorry to tell the WiFi over SDIO is currently not supported, it’s under discussing internally for the plan, but no schedule.

Hi @kayccc, WiFi over SDIO worked in L4T 32.6 setup. Is there any limitation with L4T 34.1.1?

Actually, SDIO wifi is never validated over Jetson NX. Even on rel-32.6.

@WayneWWW, We got it working earlier. But now SDIO bus itself is not up. I would like to know if there is any change from Kernel 4.9 to 5.10 regarding SDIO bus?

We cannot list it out since there are too much changes in kernel.

Hi, But why don’t I get this below print?
“mmc1: new ultra high speed SDR104 SDIO card at address 0001”
So SDIO bus registration is not successful?

Hi Wayne, any response?