GPIO Boot Overrides in i.MX6ULL

[ko-hey]

Hi all

I have a question about GPIO Boot Overrides.

According to the Table 8-2 in reference manual in i.MX6ULL, BT_FREQ and DISABLE_SDMMC_MFG seems that it can be GPIO boot overrides.

Because the item of GPIO is "yes".

However, there are no description about which pin can override BT_FREQ and DISABLE_SDMMC_MFG.

Which pin can override BT_FREQ and DISABLE_SDMMC_MFG ?

Ko-hey

[art]

Actually, this is just a typo in the Reference Manual document. No GPIO override is available for the BT_FREQ and DISABLE_SDMMC_MFG eFuses. Only the BOOT_CFG1[7:0], BOOT_CFG2[7:0] and BOOT_CFG4[7:0] eFuses can be overridden by GPIO at boot time.

Have a great day,
Artur

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[stephenbialkows]

Artur,

I have set up GPIOs to boot from ECSPI (BOOT_MODE=2, BT_FUSE_SEL=0, BT_CFGn[7:0] as proposed in table 8-20 iMX6ULL RM rev1).  SCR.SBMR=0x03000030, and SCR.SBMR2=0x02000001 confirms this. 

However, the target always boots from SD/MMC.  When I remove the SD card, the PC stays in Boot ROM.  Does the DISABLE_SDMMC_MFG fuse have to be blown to boot from devices other than the SD/MMC?  Figure 8-27 suggests otherwise.  

Please clarify.  I don't want to blow fuses unless necessary.  

Thanks!

Stephen

[ko-hey]

Could someone answer and support this thread ?

Ko-hey