uboot-phytec

HACK: mmc: k3_arasan: Skip probing of non-boot devices during SPL

On the Texas Instruments K3 family of devices with multiple SHDCI
controllers being present and declared in the DTS file the probing of
those controllers during the very early stages of boot especially before
System Firmware (SYSFW) has performed a baseline device initialization
causes issues when the non-boot SHDCI controller is being accessed.

This for example leads to the following error being output to the U-Boot
console...

sdhci_reset: Reset 0x1 never completed.

...while also unnecessarily prolonging the boot time by 100ms due to the
associated timeout mechanism. Furthermore even after SYSFW is active the
repeated probing of the non-active controller during the next boot stage
also negatively impacts the overall boot time.

To address this implement a HACK that will skip over the probing of SHDCI
controller(s) not involved into the boot process during SPL execution.
Doing so has the advantage of not impacting the internal U-Boot mechanisms
that rely on the SPL MMC device index.

Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>